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Notice2026-10611

New Car Assessment Program

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Published

May 28, 2026

Issuing agencies

Transportation DepartmentNational Highway Traffic Safety Administration

Abstract

This notice requests comment on a proposal to update the NHTSA's New Car Assessment Program (NCAP) by adding rear automatic braking (RAB) systems with pedestrian avoidance ability to the advanced driver assistance systems (ADAS) technologies NHTSA currently recommends. NHTSA proposes to identify and evaluate vehicles in the marketplace that offer systems that pass NCAP performance test criteria for RAB. The proposed updates to NCAP would give consumers important safety information about technologies designed to prevent crashes with pedestrians when the vehicle is moving in reverse.

Full Text

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<title>Federal Register, Volume 91 Issue 102 (Thursday, May 28, 2026)</title>
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[Federal Register Volume 91, Number 102 (Thursday, May 28, 2026)]
[Notices]
[Pages 31834-31858]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-10611]

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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

[Docket No. NHTSA-2026-1156]
RIN 2127-ZA28

New Car Assessment Program

AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation (Department or DOT).

ACTION: Request for comments (RFC).

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SUMMARY: This notice requests comment on a proposal to update the
NHTSA's New Car Assessment Program (NCAP) by adding rear automatic
braking (RAB) systems with pedestrian avoidance ability to the advanced
driver assistance systems (ADAS) technologies NHTSA currently
recommends. NHTSA proposes to identify and evaluate vehicles in the
marketplace that offer systems that pass NCAP performance test criteria
for RAB. The proposed updates to NCAP would give consumers important
safety information about technologies designed to prevent crashes with
pedestrians when the vehicle is moving in reverse.

DATES: Comments should be submitted no later than July 27, 2026.

ADDRESSES: You may submit comments to the docket number identified in
the heading of this document by one of the following methods:
<bullet> Federal Rulemaking Portal: <a href="http://www.regulations.gov">http://www.regulations.gov</a>.
Follow the online instructions for submitting comments.
<bullet> Mail: Docket Management Facility, U.S. Department of
Transportation, 1200 New Jersey Avenue SE, West Building Ground Floor,
Room W12-140, Washington, DC 20590-0001.
<bullet> Hand Delivery: 1200 New Jersey Avenue SE, West Building
Ground Floor, Room W12-140, Washington, DC, between 9 a.m. and 5 p.m.
ET, Monday through Friday, except Federal Holidays. To be sure someone
is there to help you, please call 202-366-9332 before coming.
Instructions: For detailed instructions on submitting comments and
additional information on the rulemaking process, see the Public
Participation heading of the Supplementary Information section of this
document. Note that all comments received will be posted without change
to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information
provided.
Docket: For access to the docket to read background documents or
comments received, go to <a href="http://www.regulations.gov">www.regulations.gov</a>, or the street address
listed above. Follow the online instructions for accessing the dockets.
Privacy Act: Anyone can search the electronic form of all comments
received in any of our dockets by the name of the individual submitting
the comment (or signing the comment, if submitted on behalf of an
association, business, labor union, or other entity). For information
on DOT's compliance with the Privacy Act, see <a href="https://www.transportation.gov/privacy">https://www.transportation.gov/privacy</a>.

FOR FURTHER INFORMATION CONTACT: For technical issues, you may contact
Ian MacIntire, Office of Crashworthiness Standards by email at
<a href="/cdn-cgi/l/email-protection#90f9f1febefdf1f3f9fee4f9e2f5d0f4ffe4bef7ffe6">[email&#160;protected]</a>, or by phone at 202-366-1810. Address: National
Highway Traffic Safety Administration, 1200 New Jersey Avenue SE, West
Building, Washington, DC 20590-0001.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
II. Background
A. Rear Automatic Braking Systems
B. 2015 NCAP RFC
C. NCAP Roadmap
D. Euro NCAP
E. NHTSA Research
III. Purpose and Rationale
IV. Rear Automatic Braking Testing Program
A. Safety Need
B. Countermeasures Exist
C. Potential Safety Benefits
D. Objective Test Procedure Exists
V. NHTSA Research
A. Overview
B. NHTSA's 2026 Report

[[Page 31835]]

C. Research Conclusions
VI. Proposal in Detail
A. Test Objects
B. Test Scenarios and Test Conditions
C. Pass-Fail Criteria
D. Number of Trials per Test Condition
E. Awarding Credit for RAB Systems
VII. Conclusion
VIII. Economic Analysis
IX. Public Participation
X. Appendices
A. Requests for Comment

I. Executive Summary

NCAP provides comparative information on the safety performance of
new vehicles and the availability of new vehicle safety features to
assist consumers with vehicle purchasing decisions. NCAP is one of
several programs that NHTSA uses to fulfill its mission of reducing
fatalities, injuries, and economic losses that occur on U.S. roadways.
This RFC focuses on the inclusion of RAB systems with pedestrian
avoidance capability in NCAP.
RAB is an advanced driver assistance technology designed to apply a
vehicle's brakes automatically when reversing if an obstacle is
detected in its path. The technology complements existing rear
visibility systems such as mirrors and cameras by intervening
automatically to prevent or mitigate backover crashes. Backover crashes
are crashes where non-occupants of vehicles (such as pedestrians or
cyclists) are struck by vehicles moving in reverse. While most current
RAB systems are not designed to detect and avoid pedestrians, NHTSA's
testing of RAB systems has shown the potential for pedestrian detection
and avoidance of backover crashes.
Backover crashes often occur in parking lots or driveways where
pedestrians are more likely to be present and vehicles are making
backing maneuvers. Vehicle blind spots limit what drivers can see
behind a vehicle, making backing maneuvers particularly dangerous for
children who may be too small to be seen. According to data from the
Fatality Analysis Reporting System (FARS) and the Crash Report Sampling
System (CRSS) for the years 2017 through 2022, approximately 111,000
crashes occurred annually that involved a passenger vehicle backing
into a pedestrian, cyclist, fixed object, parked vehicle, or moving
object. These backing crashes resulted in an average of 69 fatalities
each year, 36 of which involved pedestrians, and with a
disproportionate number of small child victims.
In support of this proposal, NHTSA conducted research to evaluate
various vehicles' RAB system performance in different test scenarios
and test conditions. The testing demonstrated that while current RAB
systems can prevent some backover crashes, their performance varies
across vehicle models and test conditions. The research developed a
standardized, objective procedure to assess RAB performance in
scenarios involving pedestrians.
NHTSA proposes to assess RAB system performance in two test
scenarios: (1) Reversing Vehicle--Stationary Pedestrian Test Mannequin
and (2) Reversing Vehicle--Moving Pedestrian Test Mannequin. In each of
these test scenarios, the vehicle is reversing at a speed of four km/h
(2.5 mph) or eight km/h (5 mph).\1\ All test scenarios are conducted in
daylight conditions. Two test mannequins are utilized for each speed
condition--the 4activePA-adult articulated pedestrian test mannequin
(adult mannequin) and the 4activePS-child static two-year-old
pedestrian test mannequin with posable but fixed arms and legs (two-
year-old mannequin).\2\
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\1\ The test vehicle speeds of four and eight km/h were selected
because they correspond to common real-world backing speeds in
residential driveways and parking environments, and they align with
the testing speeds used in the 2023 Euro NCAP protocol for Car-to-
Pedestrian Reverse tests.
\2\ The 4activePA-adult and the 4activePS-child pedestrian
mannequins comply with ISO 19206-2:2018, ``Road vehicles--Test
devices for target vehicles, vulnerable road users, and other
objects, for assessment of active safety functions--Part 2:
Requirements for pedestrian targets,'' and are compliant for use in
Euro NCAP's assessment of RAB systems.
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In the stationary pedestrian scenario, the pedestrian test
mannequin is stationary with articulation (if available) switched off,
facing sideways (towards the driver's side of the test vehicle), and
located at a 25, 50, or 75 percent ``overlap'' as the vehicle travels
rearward at four km/h or eight km/h. The term ``overlap'' in the
context of RAB testing is the location of the point on the rear of the
vehicle that would make contact with the test mannequin if no braking
occurred. For the stationary pedestrian scenario, overlap is expressed
as a percentage of the subject vehicle's overall width measured from
the vehicle's driver side outer edge.
In the moving pedestrian scenario, the pedestrian test mannequin
moves perpendicular to the rearward motion of the vehicle. In this test
scenario, the adult mannequin, moving at five km/h (3.1 mph), or the
two-year-old mannequin, moving at 3.2 km/h (two mph), approaches the
vehicle traveling rearward, from either the left or right side such
that the potential point of impact is in the middle of the vehicle rear
(i.e., 50 percent overlap).
Collectively, the proposed two scenarios result in a total of 20
test conditions (12 test conditions in stationary pedestrian scenario
and eight test conditions in moving pedestrian scenario) for evaluating
RAB system performance in a vehicle. The proposed test matrix is
presented in Table 1 below:

Table 1--Proposed Test Matrix for the NCAP RAB Evaluation
----------------------------------------------------------------------------------------------------------------
Vehicle speed in reverse
Approach Test object and -------------------------
Test scenario direction related speed Test object overlap 4 km/h (2.5 8 km/h (5
mph) mph)
----------------------------------------------------------------------------------------------------------------
Stationary Pedestrian in Facing Left..... Adult........... 25 percent......... 1 1
Resting Position \3\ with 50 percent......... 1 1
Articulation (if any) 75 percent......... 1 1
Switched Off.
2-year-old child 25 percent......... 1 1
50 percent......... 1 1
75 percent......... 1 1
----------------------------------------------------------------------------------------------------------------
Test Conditions--Stationary12edestrian Scenario
----------------------------------------------------------------------------------------------------------------
Moving Pedestrian............ From Right...... Adult, 5 km/h 50 percent......... 1 1
(3.1 mph). 50 percent......... 1 1
2-year-old
child, 3.2 km/h
(2 mph).

[[Page 31836]]

From Left....... Adult, 5 km/h 50 percent......... 1 1
(3.1 mph). 50 percent......... 1 1
2-year-old
child, 3.2 km/h
(2 mph).
----------------------------------------------------------------------------------------------------------------
# Test Conditions--Moving Pedestrian Scenario 8
----------------------------------------------------------------------------------
# Total Test Conditions for RAB Evaluation............20.....
----------------------------------------------------------------------------------------------------------------

The proposed performance criteria assessed in the tests for
evaluating RAB performance are: (1) the vehicle shall not contact the
test mannequin; (2) an auditory warning shall be provided prior to RAB
system brake application onset; (3) the RAB system shall default to
``ON'' after each ignition/key cycle; and (4) after the vehicle comes
to a complete stop, its brakes shall not be released unless test
mannequin is no longer in the vehicle's path or the driver performs a
deliberate override action.
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\3\ Resting Position means the pedestrian mannequin is standing
upright with relaxed arms positioned vertically along the sides of
the mannequin.
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NHTSA proposes to conduct only one trial per test condition, which
results in a total of 20 tests for evaluating a vehicle's RAB system.
NHTSA proposes that vehicles must pass (i.e., meet the four proposed
performance criteria) all 20 tests to receive RAB credit. NHTSA
proposes to identify vehicles with RAB systems that receive RAB credit
by way of a check mark on the NHTSA website. Until a crash avoidance
rating system is developed and implemented, the check mark on the NHTSA
website will remain the primary method of notifying consumers of
available RAB systems meeting NHTSA's performance criteria.
This proposal aligns with NHTSA's NCAP Roadmap, which outlines mid-
term and long-term updates to the program. RAB has been identified as a
mid-term addition to NCAP's crash avoidance testing. The proposed tests
and evaluation criteria for RAB are similar to those utilized in the
2023 European New Car Assessment Program protocol (2023 Euro NCAP
protocol),\4\ with some modifications to address better the safety
concern in the United States. Specifically, while the 2023 Euro NCAP
protocol utilizes a seven-year-old child test mannequin, NHTSA proposes
to use the 4active-PS static two-year-old pedestrian test mannequin
(two-year-old mannequin) because a large percentage of the pedestrian
fatalities stemming from impacts with the rear of vehicles while they
are backing are associated with children one to two years of age.
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\4\ See Section 7.2 of <a href="https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf">https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf</a>. Specifically, Car-to-
Pedestrian-Reverse-Adult (CPRA) and Car-to-Pedestrian-Reverse-Child
(CPRC) scenarios.
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The implementation of this proposal would expand NCAP's consumer
information offerings to cover a feature that addresses directly
pedestrian and child safety in backing scenarios. Through this RFC,
NHTSA seeks public comment on its proposal to include RAB in NCAP,
including the test procedures and performance criteria under
consideration. NHTSA includes requests for public comment in this
notice on specific topics that are also numbered and compiled for the
reader's convenience in Appendix A. To ensure that NHTSA addresses all
comments, NHTSA requests that commenters provide the corresponding
request for comment number(s) in their responses.

II. Background

A. Rear Automatic Braking Systems

RAB is an advanced driver assistance technology designed to apply
brakes automatically when a vehicle is traveling in reverse and an
object or person is detected in its path. Unlike traditional rear
visibility systems such as mirrors or rearview cameras, which rely on
the driver to observe and react, RAB intervenes directly by applying
the vehicle's brakes. This is done automatically, independent of driver
input, with the intent to prevent or mitigate a rearward collision.
Manufacturers employ sensors or cameras to identify potential obstacles
behind the vehicle and activate braking when needed. The rear automatic
braking action is generally preceded by a warning to the driver
notifying them of an impending collision with object(s) to the rear of
the vehicle.
Though many RAB systems in current vehicles are intended mainly to
prevent vehicle damage due to impact with inanimate objects while the
vehicle is reversing, there is potential for RAB systems to enhance the
protection of adult and child pedestrians, who are at risk in backover
crashes. Backover crashes often occur at low speeds in residential
driveways, parking lots, and other non-roadway environments where young
children may be difficult for drivers to see. While technologies such
as rear visibility cameras have improved driver awareness of their
surroundings, this safety feature remains dependent on driver vigilance
and reaction time. RAB extends protection beyond the driver's
capability by providing automatic intervention when an adult or child
pedestrian is present in a moving vehicle's rearward path.

B. 2015 NCAP RFC

In a 2015 RFC, NHTSA proposed including RAB as part of the NCAP
program.\5\ However, RAB systems and the test procedure \6\ proposed
were different at that time from what is now being considered. The 2015
RFC proposed a feature confirmation test in which the vehicle under
test was placed in reverse and allowed to roll backward from rest by
simply releasing the brake pedal. The RAB system was expected to detect
a static child-sized mannequin behind the vehicle and automatically
stop the vehicle before making contact. The test object in that draft
procedure was limited to a stationary pedestrian test mannequin placed
at three different degrees of overlap behind the vehicle, and the test
ended either when the RAB system stopped the vehicle or when the
vehicle contacted the mannequin. The system would need to avoid
contacting the mannequin in all three overlap percentages (25 percent,
50 percent, and 75 percent) to receive credit for passing performance.
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\5\ See 80 FR 78522 (Dec. 16, 2015), available at <a href="https://www.federalregister.gov/documents/2015/12/16/2015-31323/new-car-assessment-program">https://www.federalregister.gov/documents/2015/12/16/2015-31323/new-car-assessment-program</a>.
\6\ See <a href="https://www.regulations.gov/document/NHTSA-2015-0119-0030">https://www.regulations.gov/document/NHTSA-2015-0119-0030</a>.

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[[Page 31837]]

In the 2015 RFC, NHTSA proposed to assess RAB performance using a
rudimentary test procedure developed to reflect the state of RAB
technology at the time. Then-current RAB systems were generally
designed for object detection and were not widely capable of pedestrian
detection. In contrast, modern RAB technology has expanded
functionality and can be assessed under much more robust and realistic
conditions. Accordingly, current procedures specify controlled reverse
speeds rather than having the vehicle idle rearward, incorporate both
stationary and moving pedestrian test mannequins, and require testing
at different overlap percentages.
Because of the expanded capabilities of RAB systems in recent
years, modifications and additions to the associated test procedures,
and fundamental differences in system performance expectations since
NHTSA first introduced the concept of RAB in its 2015 RFC notice,
comments submitted in response to that notice are no longer considered
relevant and are not addressed herein. NHTSA invites comment on the
current RAB systems being considered for inclusion in NCAP.

C. NCAP Roadmap

The NCAP roadmap sets forth NHTSA's phased strategy for advancing
the program over the coming years by incorporating new crash avoidance,
crashworthiness, and vulnerable road user protection measures.\7\ The
roadmap is intended to provide transparency about how NCAP will evolve,
giving consumers access to clearer information on vehicle safety and
encouraging manufacturers to integrate emerging safety technologies
into their new vehicle models. NHTSA explained that goals listed on the
roadmap aim to protect both occupants and vulnerable road users.\8\
Within this framework, RAB has been identified as a mid-term addition
to NCAP. Its inclusion reflects NHTSA's recognition of the safety
technologies designed to prevent backover crashes, particularly those
involving pedestrians of all sizes, including children.
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\7\ See <a href="https://www.nhtsa.gov/sites/nhtsa.gov/files/2024-11/NCAP-Roadmap-11182024-web.pdf">https://www.nhtsa.gov/sites/nhtsa.gov/files/2024-11/NCAP-Roadmap-11182024-web.pdf</a>.
\8\ See 89 FR 93000 (Nov. 25, 2024), available at <a href="https://www.federalregister.gov/documents/2024/11/25/2024-27446/new-car-assessment-program-final-decision-notice-crashworthiness-pedestrian-protection">https://www.federalregister.gov/documents/2024/11/25/2024-27446/new-car-assessment-program-final-decision-notice-crashworthiness-pedestrian-protection</a>.
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D. Euro NCAP

Euro NCAP has developed a protocol for evaluating RAB systems and
has been testing RAB systems since January 2020.\9\ Euro NCAP treats
RAB as part of its vulnerable road user protection efforts. The Euro
NCAP, ``TEST PROTOCOL--AEB/LSS VRU systems Implementation 2023, Version
4.5.1,'' \10\ referred to in this RFC as the 2023 Euro NCAP protocol,
contains test conditions for evaluating a vehicle's RAB system's
ability to avoid contact with either a stationary or moving pedestrian
test mannequin when reversing at low speeds. The vehicle test speeds
are four km/h and eight km/h, representing common reversing speeds in
parking areas. All test scenarios are conducted in daylight conditions.
The evaluation uses two articulating pedestrian test mannequins: an
adult male and a seven-year-old child. These adult and child pedestrian
test mannequins used in the 2023 Euro NCAP protocol RAB tests are in
accordance with the performance requirements, dimensions, and
reflection properties for pedestrian test mannequins specified in the
International Organization for Standardization (ISO) 19206-2.\11\
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\9\ See <a href="https://www.euroncap.com/media/79885/euro-ncap-assessment-protocol-vru-v114.pdf">https://www.euroncap.com/media/79885/euro-ncap-assessment-protocol-vru-v114.pdf</a>.
\10\ See <a href="https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf">https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf</a>.
\11\ ISO 19206-2:2018, ``Road vehicles--Test devices for target
vehicles, vulnerable road users, and other objects, for assessment
of active safety functions--Part 2: Requirements for pedestrian
targets.''
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In the tests with a stationary pedestrian test mannequin, the
vehicle travels rearwards at four km/h or eight km/h towards the
pedestrian test mannequin (adult or child articulating pedestrian test
mannequin with articulation switched off) facing sideways (left or
right direction, selected by testing facility). In these tests, the
stationary pedestrian test mannequin is positioned such that the rear
of the vehicle could potentially strike the pedestrian at a location
from the driver's side vehicle edge that is 25, 50, or 75 percent of
the vehicle's width (25 percent, 50 percent, or 75 percent overlap).
In the tests with a moving pedestrian test mannequin, the
articulating pedestrian test mannequin is initially located four meters
left of the test vehicle's longitudinal centerline and travels at a
speed of km/h perpendicular to the test vehicle's line of travel such
that potential impact with the rear of the vehicle occurs when the
mannequin is located at the vehicle's longitudinal centerline (50
percent overlap). The test matrix for evaluating RAB in the 2023 Euro
NCAP protocol is shown in Table 2, and a schematic of the RAB test
procedure with stationary pedestrian test mannequins and moving
pedestrian test mannequins is shown in Figure 1. As shown in Table 2,
EuroNCAP assessment of RAB system performance involves a total of 8
test conditions.

Table 2--2023 Euro NCAP Protocol Test Matrix for RAB Evaluation
----------------------------------------------------------------------------------------------------------------
Vehicle speed in reverse
Approach -------------------------
Test scenario direction Test object Test object overlap 4 km/h (2.5 8 km/h (5
mph) mph)
----------------------------------------------------------------------------------------------------------------
Stationary Pedestrian in Facing Left or Adult........... 25 percent......... ........... 1
Resting Position with Right (Selected 50 percent......... 1 ...........
Articulation Switched Off. by Testing 75 percent......... ........... 1
Facility).
7-year-old child 25 percent......... 1 ...........
50 percent......... ........... 1
75 percent......... 1 ...........
----------------------------------------------------------------------------------------------------------------
# Test Conditions--Stationary Pedestrian6Scenario
----------------------------------------------------------------------------------------------------------------
Moving Pedestrian............ From Left....... Adult, 5 km/h 50 percent......... 1 ...........
(3.1 mph).
7-year-old 50 percent......... ........... 1
child, 5 km/h
(3.1 mph).
----------------------------------------------------------------------------------------------------------------
# Test Conditions--Moving Pedestrian S2enario
----------------------------------------------------------------------------------
# Total Test Conditions for RAB Eval8ation
----------------------------------------------------------------------------------------------------------------

[[Page 31838]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.017

Figure 1. Schematic of the RAB Test Procedure in the 2023 Euro NCAP
Protocol (adult and child pedestrian scenario: moving pedestrian (left)
and stationary pedestrian (right).12
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\12\ Reproduced with permission from Euro NCAP Test Protocol--
AEB/LSS VRU Systems. Version 4.5.1 February 2024. Figure 7-9.
<a href="https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf">https://www.euroncap.com/media/80156/euro-ncap-aeb-lss-vru-test-protocol-v451.pdf</a>.

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[[Page 31839]]

The performance criteria are that the vehicle must not contact the
pedestrian test mannequin, and once the brakes are engaged, they must
remain applied until the pedestrian is no longer in the vehicle's path.
The 2023 Euro NCAP protocol also requires that the RAB system default
to ``ON'' at each ignition cycle so drivers cannot disable the system
by default. These procedures and performance criteria have become an
important benchmark for evaluating RAB systems worldwide.
In October 2025, Euro NCAP released a new protocol, ``Crash
Avoidance Low Speed Collisions Protocol, Version 1.1,'' \13\ that
contains updated RAB test procedures, which differ in multiple ways
from the 2023 Euro NCAP protocol for evaluating RAB and from NHTSA's
proposed RAB test protocol. NHTSA seeks information regarding the
motivation for the changes in RAB test scenarios between the 2023 Euro
NCAP Protocol (Test Protocol-AEB/LSS VRU Systems; Implementation 2023,
Version 4.5.1, February 2024) and the October 2025 Euro NCAP Protocol,
``Crash Avoidance Low Speed Conditions Protocol, Version 1.1 October
2025, Implementation January 2026.''
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\13\ See <a href="https://www.euroncap.com/media/91777/euro-ncap-protocol-crash-avoidance-low-speed-collisions-v11.pdf">https://www.euroncap.com/media/91777/euro-ncap-protocol-crash-avoidance-low-speed-collisions-v11.pdf</a>.
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E. NHTSA Research

NHTSA completed a research program to evaluate the performance of
modern RAB systems and to develop an objective and repeatable test
procedure suitable for use in NCAP.\14\ This effort built upon a draft
procedure first proposed in the Agency's 2015 RFC \15\ and incorporated
advancements to address current vehicle technologies and real-world
crash concerns, as well as comments received from manufacturers. The
revised procedure accounts for both stationary and moving pedestrian
scenarios, includes defined reversing speeds, and uses robotic steering
and pedal controllers to ensure consistency. The revised procedure also
considered the procedures established by the 2023 Euro NCAP protocol
and sought to harmonize where possible.
---------------------------------------------------------------------------

\14\ Mazzae, E.N., Sun, A.L., & Baldwin, G.H.S., Rear Automatic
Braking Feature Confirmation Test Procedure Refinement (2026). A
copy of this report is available in the docket for this notice.
\15\ See 80 FR 78522 (Dec. 16, 2015), available at <a href="https://www.federalregister.gov/documents/2015/12/16/2015-31323/new-car-assessment-program">https://www.federalregister.gov/documents/2015/12/16/2015-31323/new-car-assessment-program</a>.
---------------------------------------------------------------------------

Testing was conducted at NHTSA's Vehicle Research and Test Center
on four RAB-equipped 2022 model year (MY) vehicles: Cadillac XT4, Ford
Mustang Mach-E, Jeep Grand Cherokee L, and Subaru Outback Touring. Each
vehicle was evaluated across a structured test matrix that included a
wide range of pedestrian and obstacle conditions. In total, the program
carried out roughly 24 distinct test conditions, using both adult and
child pedestrian test mannequins in stationary pedestrian scenario and
moving pedestrian scenario, with overlap of 25, 50, and 75 percent, and
reversing speeds of four and eight km/h. The addition of a test object
programmable platform for moving pedestrian test mannequins and robotic
vehicle controls allowed for repeatable testing of moving pedestrian
encounters that more closely reflect real-world backover risks.
The research, presented in a 2026 report titled ``Rear Automatic
Braking Feature Confirmation Test Procedure Refinement'' (NHTSA's 2026
Report),\16\ found that RAB system performance was not consistent
across vehicle models. Though all systems demonstrated the potential to
prevent certain backover crash scenarios, none of the vehicles
consistently avoided collisions with moving pedestrian test mannequins.
Performance was generally better at lower test speeds, with shorter
test objects, and with stationary test objects. These findings indicate
that while RAB can contribute important safety benefits, especially for
vulnerable populations such as children, there is potential for further
refinement of the technology.
---------------------------------------------------------------------------

\16\ Mazzae, E.N., Sun, A.L., & Baldwin, G.H.S., Rear Automatic
Braking Feature Confirmation Test Procedure Refinement (2026). A
copy of this report is available in the docket for this notice.
---------------------------------------------------------------------------

III. Purpose and Rationale

Establishing an NCAP evaluation program for RAB would encourage
manufacturers to equip new vehicles with RAB systems having the ability
consistently to detect and avoid pedestrians in the path of a reversing
vehicle. Backover crashes, while a small subset of total crashes,
disproportionately affect young children and older adults, who are
often struck by vehicles reversing. NHTSA's analysis of crash data
indicates that these incidents present a significant safety concern due
to their severity and the demographics of the victims. Incorporating
RAB into NCAP promotes the advancement of technologies that protect
these vulnerable road users.
This notice seeks comment on NHTSA's proposal to add RAB
evaluations to NCAP's crash avoidance program. NHTSA believes that RAB
system performance and test procedures have improved to such an extent
that inclusion of such testing in NCAP has the potential to reduce
fatalities and injuries associated with backover crashes, not simply to
prevent vehicle damage due to impact with inanimate objects. Research
conducted by NHTSA has demonstrated that RAB systems are
technologically feasible but currently vary widely in their
performance, particularly when detecting and responding to pedestrians,
including small children. By establishing objective NCAP test
procedures, NHTSA will provide consumers with clear, comparable
information on RAB performance, while encouraging manufacturers to
design more effective systems with pedestrian detection and avoidance
capability.
NHTSA notes that the inclusion of RAB in NCAP is consistent with
NHTSA's established prerequisites for adding new technologies to the
program: (1) the technology addresses a demonstrated safety need; (2)
system designs for countermeasures exist to mitigate the safety
problem; (3) those designs have safety benefit potential; and (4) a
performance-based objective test procedure exists to assess system
performance. These four prerequisites are discussed in detail below in
the following section. By implementing the inclusion of RAB in NCAP,
NHTSA seeks to promote the development and adoption of more robust RAB
systems, improve consumer awareness of their function and importance,
and reduce injuries and fatalities resulting from backover crashes.

IV. Rear Automatic Braking Testing Program

A. Safety Need

NHTSA analyzed 2017 to 2022 data files from the Fatality Analysis
Reporting System (FARS) and the Crash Reporting Sampling System (CRSS).
For this time period, there were an average of 5.82 million police-
reported crashes involving passenger vehicles (PV) \17\ per year,
including 31,018 fatal crashes per year.
---------------------------------------------------------------------------

\17\ Passenger vehicles (also referred to as light vehicles)
include cars, crossovers, sport utility vehicles (SUVs), and light
trucks and vans with a gross vehicle weight rating of 10,000 pounds
(lbs) or less.
---------------------------------------------------------------------------

Backing safety technologies such as RAB are designed to mitigate or
prevent only a subset of these crashes. These ``target backing
crashes'' encompass cases where a PV backed into (1) pedestrians, (2)
cyclists, (3) parked vehicles, (4) fixed objects, and (5)

[[Page 31840]]

moving vehicles and objects. Annually, between 2017 and 2022,
approximately 111,000 target backing crashes occurred, including 66
fatal crashes. These crashes resulted in an annual average of 69
fatalities and 28,034 MAIS \18\ 1-5 injuries. Table 3 summarizes key
crash statistics for target backing crashes.\19\ The values in Table 3
have been annualized and rounded to the nearest whole number, so the
listed totals may not match the respective column summations exactly.
---------------------------------------------------------------------------

\18\ The Abbreviated Injury Scale (AIS) is a classification
system for assessing impact injury severity. AIS ranks individual
injuries by body region on a scale of 1 to 6 where 1 = minor, 2 =
moderate, 3 = serious, 4 = severe, 5 = critical, and 6 = maximum
(untreatable). MAIS represents the maximum injury severity, or AIS
level, recorded for an occupant (i.e., the highest single AIS for a
person with one or more injuries).
\19\ The values in Table 3 have been annualized and rounded to
the nearest whole number, so the listed totals may not match the
respective column summations exactly.

Table 3--Annualized Target Backing Safety Population by Crash Scenario \19\
----------------------------------------------------------------------------------------------------------------
MAIS 1-5
Crash scenario Total crashes Fatal crashes Fatalities Injuries
----------------------------------------------------------------------------------------------------------------
PV backed into Pedestrian....................... 1,709 36 36 1,449
PV backed into Cyclist.......................... 381 2 2 300
PV backed into Parked Vehicle................... 14,557 1 1 2,199
PV backed into Fixed Object..................... 943 1 1 84
PV backed into Vehicle/Moving Object............ 93,486 27 30 24,001
---------------------------------------------------------------
Total....................................... 111,075 66 69 28,034
----------------------------------------------------------------------------------------------------------------

In April 2014, NHTSA published a final rule \20\ amending Federal
Motor Vehicle Safety Standard (FMVSS) No. 111 ``Rear visibility,'' to
expand the required field of view of passenger vehicles when placed
into reverse gear. Specifically, NHTSA required that vehicles display a
rearview image covering a specific area behind the vehicle. Automakers
complied with this final rule by installing rearview cameras and in-
vehicle visual displays to aid the driver's visibility when backing.
The rear visibility final rule established a phase-in schedule for
compliance that allowed manufacturers to implement rear visibility
systems from May 2016 through May 2018.\21\
---------------------------------------------------------------------------

\20\ See 79 FR 19178, available at <a href="https://www.federalregister.gov/documents/2014/04/07/2014-07469/federal-motor-vehicle-safety-standards-rear-visibility">https://www.federalregister.gov/documents/2014/04/07/2014-07469/federal-motor-vehicle-safety-standards-rear-visibility</a>.
\21\ See 79 FR 19181, available at <a href="https://www.federalregister.gov/documents/2014/04/07/2014-07469/federal-motor-vehicle-safety-standards-rear-visibility">https://www.federalregister.gov/documents/2014/04/07/2014-07469/federal-motor-vehicle-safety-standards-rear-visibility</a>.
---------------------------------------------------------------------------

To establish the target population that would benefit from RAB
systems, NHTSA analyzed FARS and CRSS data from 2017-2022, which
reflects a time period when many older model year (MY) vehicles were
not yet equipped with the specified rearview cameras. NHTSA estimated
an adjustment factor to account for the full effects of the rear
visibility final rule on the target backing safety population for RAB.
This adjustment factor was estimated using information on: (1) annual
passenger vehicle sales, (2) vehicle survivability, (3) rearview camera
equipage rates,\22\ and (4) rearview camera system effectiveness.\23\
The resulting target population adjustment factor ranges from 76.3-80.3
percent, which accounts for the range of effectiveness (28 percent to
33 percent) of rearview camera systems. The resulting target population
for RAB system consideration is summarized in Table 4. The details of
NHTSA's analysis for determining the target population for RAB systems
is included in the docket of this RFC.
---------------------------------------------------------------------------

\22\ To determine rear-view camera equipage rates, NHTSA used
information from the 2022 Ward's Automotive Yearbook for data from
2017-2021, and the 2022 sales data from the National Automobile
Dealership Association (NADA) .
\23\ Rear-view camera system effectiveness was established as
28-33 percent in the Final Regulatory Impact Analysis (FRIA) for the
rear visibility final rule.

Table 4--Annual Backover Crashes and Resulting Fatalities and Injuries After Adjusting for the Effect of
Rearview Camera Systems
----------------------------------------------------------------------------------------------------------------
Crash scenario Total crashes Fatal crashes Fatalities MAIS 1-5 MAIS 2-5
----------------------------------------------------------------------------------------------------------------
PV backed into Pedestrian (76.3 1,304 27 27 1,106 223
percent adjustment)............
PV backed into Pedestrian (80.3 1,372 29 29 1,163 234
percent adjustment)............
----------------------------------------------------------------------------------------------------------------

Previous evaluations examining target crashes for different
advanced driver assistance systems indicated that rear-end collisions
represented only 0.2 percent of fatalities and 1.3 percent of injuries
resulting from vehicle crashes.\24\ However, as presented in a later
section of this notice, a large percentage of the target population of
fatalities and injuries associated with RAB include children. NHTSA
seeks comment on whether the inclusion of RAB technology in NCAP is
appropriate.
---------------------------------------------------------------------------

\24\ 89 FR 95916. See Table 1.
---------------------------------------------------------------------------

B. Countermeasures Exist

Automotive manufacturers began equipping vehicles with rear
automatic braking systems voluntarily as early as model year 2013.
However, for the two MY 2013 vehicle models examined by NHTSA, neither
owner's manual characterized the rearward detection and collision
avoidance system as being able to detect pedestrians. Since 2013, RAB
systems have been implemented by an increasing number of manufacturers
throughout their vehicle fleets. Table 5 below shows the increase in
market penetration of RAB systems from MY 2022 to MY 2025 based on data
submitted to NCAP by manufacturers. However, of the 18 manufacturers
that offered RAB systems for MY 2025 vehicles, only 12 specified that
the system was designed to detect pedestrians.

Table 5--Market Penetration Rates of Projected Sales Volume
------------------------------------------------------------------------
MY 2022 MY 2025
------------------------------------------------------------------------
Number of Manufacturers that 14................ 18.
Offered RAB.
Percent of Vehicle Fleet with 14.8 percent...... 31.6 percent.
Standard RAB.

[[Page 31841]]

Percent of Vehicle Fleet with 14.3 percent...... 23.3 percent.
Optional RAB.
Total Percent of Vehicle Fleet 29.1 percent...... 54.9 percent.
with RAB.
------------------------------------------------------------------------

Manufacturers utilize a range of sensor types for their RAB
systems, including radar, sonar (ultrasonic), and cameras. Many
manufacturers utilize a combination of these technologies to optimize
safety system performance. NHTSA has conducted experimental testing
with vehicles using each of these sensor types and determined that they
have the ability to detect pedestrians, to some extent. This testing is
described in detail later in this notice.

C. Potential Safety Benefits

In July 2019, NHTSA published a report \25\ on the assessment of a
draft test procedure for confirming the presence of an RAB system
capable of detecting stationary objects behind a reversing vehicle,
warning the driver of the presence of the objects, and automatically
engaging the available braking system to stop the vehicle. This draft
test procedure, using a stationary and non-articulating child
pedestrian test mannequin, was similar to the approach outlined in the
2015 NCAP RFC for RAB systems, The assessment included testing of a
2014 Cadillac ATS, 2014 Infiniti Q50, and a 2015 Chrysler 200C, each of
which was equipped with a safety system designed to detect objects
rearward of the vehicle and apply the brakes to avoid contact. Results
of this testing effort showed that each vehicle had a rear automatic
braking feature that could effectively detect the pedestrian test
mannequin, provide visual and auditory warnings to the driver, and
apply the brakes in response to object detection. However, none of the
systems were 100 percent effective at meeting the test procedure's
performance criteria, which required that the vehicle stop before
reaching the location of the test object such that there would be no
physical contact with the test object for each of the three test object
locations assessed.
---------------------------------------------------------------------------

\25\ Mazzae, E.N., Baldwin, G.H.S., & Andrella, A.T., Rear
automatic braking feature confirmation test--Draft test procedure
assessment (Report No. DOT HS 812 766), Washington, DC: National
Highway Traffic Safety Administration (July 2019).
---------------------------------------------------------------------------

NHTSA's 2026 Report outlined testing done to assess a revised
version of the draft test procedure for assessing the performance of
vehicle RAB systems.\26\ The revised test procedure accounted for
multiple factors such as additional test conditions involving moving
pedestrians of different sizes and configurations, as well as
recommendations received in response to the 2015 RFC relating to
accommodating different types of vehicle transmission and propulsion
systems, and the use of robotic test equipment. This research assessed
the RAB systems equipped on a 2022 Cadillac XT4, 2022 Ford Mustang
Mach-E, 2022 Jeep Grand Cherokee L, and a 2022 Subaru Outback Touring.
The test results showed inconsistent performance across all RAB
systems. None of the RAB systems tested were able to avoid contacting
the test objects for all testing speeds when the test object was in
motion. However, when the test object was not in motion, one RAB system
was able to avoid contact for 100 percent of tests with two test object
types. Findings from these test results indicate there is potential to
enhance pedestrian safety from technological advancements of RAB
systems. Including RAB evaluation in NCAP could incentivize
manufacturers to design more effective RAB systems to mitigate backover
crashes.
---------------------------------------------------------------------------

\26\ Mazzae, E.N., Sun, A.L., & Baldwin, G.H.S., Rear Automatic
Braking Feature Confirmation Test Procedure Refinement (2026). A
copy of this report is available in the docket for this notice.
---------------------------------------------------------------------------

D. Objective Test Procedures Exist

The last guiding principle comprising NHTSA's four prerequisites
when considering a new safety technology for inclusion in NCAP is
whether there is an objective test procedure to assess system
performance. NHTSA has developed a test procedure to confirm the
presence of a rear automatic braking feature having the ability to
detect and avoid pedestrians. This feature is defined as installed
vehicle equipment that has the ability to sense the presence of
objects, including stationary and moving pedestrians, behind a
reversing vehicle, warn the driver of the presence of the objects, and
automatically engage the available braking system(s) to stop the
vehicle. NHTSA's draft RAB test procedure is similar to that in the
2023 Euro NCAP protocol, but with several notable differences that will
be discussed later in this notice. The most recent draft of the
Agency's test procedure, used in NHTSA's 2026 report, is included in
the docket of this RFC.

V. NHTSA Research

A. Overview

NHTSA's July 2019 report \27\ documented the testing results of a
draft test procedure for assessing vehicle rear automatic braking
systems. For this test procedure, a rear automatic braking feature was
defined as installed vehicle equipment that has the ability to sense
the presence of objects behind a reversing vehicle, warn the driver of
the presence of the objects, and automatically engage the available
braking system(s) to stop the vehicle. The purpose of this research was
to evaluate the draft test procedure's repeatability and effectiveness
in evaluating an RAB system's ability to warn the driver of the
presence of a rear obstacle and automatically engage the vehicle's
brake system(s) to avoid striking the object.
---------------------------------------------------------------------------

\27\ Mazzae, E.N., Baldwin, G.H.S., & Andrella, A.T., Rear
automatic braking feature confirmation test--Draft test procedure
assessment (Report No. DOT HS 812 766), Washington, DC: National
Highway Traffic Safety Administration (July 2019).
---------------------------------------------------------------------------

NHTSA's 2019 draft RAB test procedure assessed the ability of a
test vehicle's RAB system to detect a child mannequin located behind
the vehicle while the vehicle was reversing. For this testing, the
child mannequin was placed 20 feet rearward of the stationary test
vehicle at one of three lateral locations on a grid (along the vehicle
centerline and two feet left and right of center). The test driver
initiated each test trial by depressing the vehicle's brake pedal,
shifting the vehicle's automatic transmission from park to reverse
gear, and then quickly fully releasing the brake pedal to allow the
vehicle to roll rearward. The vehicle was allowed to roll rearward
without accelerator pedal application until either the RAB system
intervened by automatically engaging the vehicle's brakes to bring the
vehicle to a stop, or until the vehicle struck the test object. Once
either of these two outcomes occurred, the driver depressed the
vehicle's brake pedal to ensure the vehicle came safely to a stop and
the test trial ended. This procedure was repeated for each of the three
test object positions (25 percent, 50 percent, and 75 percent overlap).
To pass the test, the vehicle was not permitted to contact the test
object for any of the three test object locations.
Overall, the test procedure was found to be repeatable and
effective in evaluating the ability of a rear automatic braking feature
to warn the driver of the presence of a rear obstacle and automatically
engage the vehicle brake system(s) to attempt to avoid striking the
object. However, some areas for

[[Page 31842]]

improvement were identified. This test procedure did not account for
variations in pedestrian size, pedestrians in motion, or manual-
transmission vehicles or electric vehicles that may not accelerate when
the brake pedal is released. In addition, NHTSA recognized that each
vehicle may have a slightly different ``idle'' speed.
---------------------------------------------------------------------------

\28\ Mazzae, E.N., Sun, A.L., & Baldwin, G.H.S., Rear Automatic
Braking Feature Confirmation Test Procedure Refinement (2026). A
copy of this report is available in the docket for this notice.
---------------------------------------------------------------------------

In NHTSA's 2026 Report, the Agency outlined its effort further to
refine and develop a draft RAB test procedure for use in NCAP.\28\ This
effort sought to investigate, implement, and confirm through testing of
RAB-equipped vehicles ways to revise the rear automatic braking system
test procedure to account for the following: (1) vehicles that do not
roll backwards when their transmission is in neutral gear and on a
level surface, such as electric vehicles, (2) test scenario involving a
moving, articulated pedestrian, (3) use of a robotic pedal controller
to achieve a specific constant reversing speed for all test vehicles
and throughout all test trials for a given vehicle, and (4) use of a
robotic steering controller-based mannequin propulsion system.
For this testing, NHTSA conducted two types of test scenarios:
Reversing Vehicle--Stationary Test Object and Reversing Vehicle--Moving
Test Object. Test procedure improvements were also implemented. These
included use of a robotic steering and pedal controller in the test
vehicles, which helped to achieve consistent and repeatable reversing
speeds and positions. In addition, the use of a robotic steering
controller-based mannequin propulsion system for controlling pedestrian
test mannequin motion provided increased consistency of motion and
speed control. Scenarios were tested with a variety of test objects and
test speeds to permit further characterization of system performance.
The test procedure was confirmed through testing of four MY 2022
vehicles equipped with RAB systems. Multiple candidate pedestrian test
conditions were found to be viable indicators of system performance. A
more in-depth discussion of this research is presented in the next
section.

B. NHTSA's 2026 Report

As discussed in NHTSA's 2026 Report, testing was conducted further
to improve NHTSA's draft RAB test procedure as well as to characterize
the performance of the latest RAB systems.
1. Vehicles Tested
NHTSA's testing evaluated four passenger vehicles equipped with RAB
systems: the 2022 Cadillac XT4, 2022 Ford Mustang Mach-E, 2022 Jeep
Grand Cherokee L, and 2022 Subaru Outback Touring. These vehicles were
selected to represent a broad range of current market offerings,
encompassing different propulsion systems, vehicle sizes, and design
segments. The Cadillac XT4 and Jeep Grand Cherokee L are conventional
sport utility vehicles with internal combustion engine propulsion
system, the Mustang Mach-E is a fully electric crossover, and the
Subaru Outback Touring is a midsize wagon-style SUV with internal
combustion engine propulsion system. The owner's manual for each of
these vehicles stated that RAB is operational when the vehicle's
transmission is in reverse gear. Together, these vehicles provided a
cross-section of the modern fleet, allowing NHTSA to examine how rear
automatic braking performance varies across manufacturers and vehicle
architectures.
2. RAB Systems Tested
Rear automatic braking systems use a combination of sensing
technologies to detect objects or pedestrians behind a vehicle while
reversing. The most common sensor types include ultrasonic sensors and
cameras. Some vehicles may also utilize radar. Ultrasonic sensors
measure distance to nearby objects at very short ranges. Cameras
provide visual detection and have the potential for classification of
pedestrians or other obstacles. Radar sensors detect larger or moving
objects at greater distances. Some modern RAB systems combine these
sensor types to improve detection reliability.
Among the vehicles tested, the Cadillac XT4 uses a combination of
cameras and ultrasonic sensing as part of its rear automatic braking
system. The Ford Mustang Mach-E also utilizes camera and ultrasonic
inputs. The Jeep Grand Cherokee L and Subaru Outback Touring utilize
only ultrasonic sensors. This range of configurations reflects a sample
of the technical approaches manufacturers may use to achieve similar
RAB functions. Table 6 provides a summary of the vehicles and RAB
systems tested.

Table 6--Vehicles and RAB Systems Tested
--------------------------------------------------------------------------------------------------------------------------------------------------------
Warning signal
Vehicle make/model/trim RAB system name RAB sensor technology RAB operating Sensor detection modality
--------------------------------------------------------------------------------------------------------------------------------------------------------
2022 Cadillac XT4 Premium Luxury... Reverse Automatic Camera, Ultrasonic.... 0.5-20 mph (1-32 km/ 0-8 ft (0-2.5 m)..... 1. Auditory/Haptic.
Braking. h). 2. Haptic.
2022 Ford Mustang Mach-E \29\...... Reverse Braking Assist Camera, Ultrasonic.... 1-7 mph (1.5-12 km/h) 0-6 ft (0-1.8 m)..... 1. Auditory.
2. Visual.
2022 Jeep Grand Cherokee L Limited ParkSense Park Assist. Ultrasonic............ 0-6 mph (0-9 km/h)... 1-6.5 ft (0.3 m-2 m). 1. Auditory.
4x4. 2. Visual.
2022 Subaru Outback Touring........ Reverse Automatic Ultrasonic............ 1-9 mph (1.5-15 km/h) 0-2.3 ft or more (0- 1. Auditory.
Braking. 0.7 m or more). 2. Visual.
--------------------------------------------------------------------------------------------------------------------------------------------------------

As shown in Table 6, most of the tested RAB systems provided both
auditory and visual warning signals, while the Cadillac allowed the
driver to select from ``alert type'' options consisting of either an
auditory signal or a haptic signal presented via the driver's seat pan.
The Cadillac's other backing crash avoidance features also could
provide visual signals consisting of either a warning triangle symbol
or a pedestrian symbol presented in the ``infotainment display.''
---------------------------------------------------------------------------

\29\ Testing was conducted with the Mach-E in the ``Whisper''
drive mode as it provided the lowest level of brake regeneration.
---------------------------------------------------------------------------

The RAB systems for these four vehicles were evaluated in different
test scenarios and test conditions, including different reverse speeds,
with stationary and moving pedestrian test mannequins of different
sizes, different overlap percentages, and pedestrian approach
direction. Three trials were conducted for each test condition.
3. Evaluation Criteria
A vehicle had to satisfy all four evaluation criteria listed below
to receive a ``pass'' for a particular test

[[Page 31843]]

trial. The evaluation criteria were as follows:
<bullet> Auditory warning before braking--The vehicle had to emit a
clear auditory warning signal before the RAB system applied the brakes
automatically, ensuring the driver was warned to provide the
opportunity for manual intervention.
<bullet> No contact with the pedestrian test mannequin--The vehicle
had to stop fully before impact, indicating the system could
successfully detect and respond to pedestrians.
<bullet> Brakes remain applied--Once braking began, the system had
to keep the brakes engaged until the pedestrian was no longer in the
vehicle's path or until the driver deliberately overrode it.
<bullet> System default-on behavior--The RAB system had to be
configured to be active at the start of every ignition cycle, ensuring
it cannot be disabled by default.
4. Vehicle Speeds
In NHTSA's 2019 report, the test speed was determined by each
vehicle's idle speed. The idle speed was the speed obtained when the
driver's foot was released from the brake pedal while the transmission
was in the reverse gear. NHTSA's 2026 Report presents the Agency's
testing of vehicles using not only the idle speed, but also a set speed
of four and eight km/h. For the four vehicles tested, each had an idle
speed between 6.00 and 6.84 km/h, as shown in Table 7.

Table 7--Average Backing Speeds Without Accelerator Application
------------------------------------------------------------------------
Vehicle Average idle backing speed
------------------------------------------------------------------------
2022 Cadillac XT4......................... 4.25 mph (6.84 km/h).
2022 Ford Mustang Mach-E.................. 3.73 mph (6.00 km/h).
2022 Jeep Grand Cherokee L................ 4.14 mph (6.66 km/h).
2022 Subaru Outback Touring............... 4.11 mph (6.61 km/h).
------------------------------------------------------------------------

For tests at idle speed, the vehicle was positioned 6.1 meters away
from the test object and allowed to roll backwards without brake or
accelerator input from the driver. For the tests conducted at a
reversing speed of four km/h and eight km/h, the vehicle started at a
distance far enough from the test object so that the test speed could
be achieved and maintained at a minimum time of two seconds before 6.1
meters from the test object was reached. The vehicle then continued
moving rearwards until the RAB system brought the vehicle to a stop, or
the vehicle struck the test object.
---------------------------------------------------------------------------

\30\ Harpster, H.R. and Lemer, N., Field Measurement of
Naturalistic Backing Behavior, DOT HS 808 532 (Dec. 1995), available
at: <a href="https://rosap.ntl.bts.gov/view/dot/2194">https://rosap.ntl.bts.gov/view/dot/2194</a>.
\31\ Mazzae, E.N., et al., ``On-Road Study of Drivers' Use of
Rearview Video System,'' DOT HS 811 024 (Sept. 2008), available at:
<a href="https://rosap.ntl.bts.gov/view/dot/63329">https://rosap.ntl.bts.gov/view/dot/63329</a>.
---------------------------------------------------------------------------

The test vehicle speeds of four and eight km/h were selected
because they correspond to common real-world backing speeds in
residential driveways and parking environments 30 31 and
they align with the testing speeds used in the 2023 Euro NCAP protocol
for Car-to-Pedestrian Reverse tests. The proposed test vehicle speeds
of four and eight km/h also cover a range above and below the typical
idle backing speed. Figures 2 and 3 present the percentage of crashes
avoided in all the test conditions evaluated for each vehicle model by
the vehicle's reversing speed. The test results show that one vehicle's
RAB system avoided more crashes at the higher speeds, but most avoided
more crashes at the lower speeds.
BILLING CODE 4910-59-P
[GRAPHIC] [TIFF OMITTED] TN28MY26.018

[[Page 31844]]

Figure 2. Effect of Vehicle Speed in Stationary Test Objects
32
---------------------------------------------------------------------------

\32\ Test objects included in these tests were as follows.
Cadillac, Ford, Subaru: Adult mannequin, 7-year-old mannequin,
Standing 2-year-old mannequin, Bollard, Pillar. Jeep: Adult
mannequin, 7-year-old mannequin, Standing 2-year-old mannequin,
Standing 1-year-old mannequin, Playing Child Target, 2-year-old
mannequin on Bobby Car, Sitting 2-year-old mannequin, Crawling 1-
year-old mannequin, Bollard, Pillar, Plastic shopping cart, Metal
shopping cart, Plastic shopping cart with adult mannequin, Metal
shopping cart with adult mannequin.
[GRAPHIC] [TIFF OMITTED] TN28MY26.019

BILLING CODE 4910-59-C

Figure 3. Effect of Vehicle Speed in Moving Pedestrian Scenario
33
---------------------------------------------------------------------------

\33\ Test objects included in these tests were as follows.
Cadillac, Ford, Subaru: Adult mannequin, 7-year-old mannequin,
Standing 2-year-old mannequin. Jeep: Adult mannequin, 7-year-old
mannequin, Standing 2-year-old mannequin, Standing 1-year-old
mannequin, Playing Child Target, 2-year-old mannequin on Bobby Car.
---------------------------------------------------------------------------

5. Test Objects
A variety of test objects were selected for the testing presented
in NHTSA's 2026 Report to aid in characterizing RAB system performance
capability. Test objects represented objects that are typically found
in real-world backing scenarios, including pedestrian test mannequins
and stationary objects such as a pillar, bollard, and shopping carts.
For travel speeds of four to eight km/h in reverse, it is unlikely that
occupants in the vehicle will sustain injuries when the vehicle's rear
impacts a pillar or bollard. On the other hand, a child or adult
impacted and subsequently run over by a vehicle that is backing at
speeds four to eight km/h could sustain serious injuries. Since NHTSA's
focus on including RAB in NCAP is to enhance safety, only the
pedestrian test mannequins and associated test results are further
discussed in this document. Details of the tests with stationary
inanimate objects are provided in the NHTSA's 2026 Report \34\ added in
the docket of this request for comment notice.
---------------------------------------------------------------------------

\34\ Mazzae, E.N., Sun, A.L., & Baldwin, G.H.S., Rear Automatic
Braking Feature Confirmation Test Procedure Refinement (2026). A
copy of this report is available in the docket for this notice.
---------------------------------------------------------------------------

The following three pedestrian test mannequins were included in the
testing of the RAB systems for the four selected vehicles: 4activePA-
adult (adult articulated pedestrian),\35\ 4activePA-child (six- to
seven-year-old child articulated pedestrian),\36\ 4activePS-child (two-
year-old child static pedestrian) \37\ in standing position. Unlike the
4activePA-adult and the 4activePA-child that are articulating, the
4activePS-child is not articulating; however, the arms and legs are
posable.
---------------------------------------------------------------------------

\35\ See <a href="https://www.4activesystems.at/4activepa">https://www.4activesystems.at/4activepa</a>.
\36\ See <a href="https://www.4activesystems.at/4activepa">https://www.4activesystems.at/4activepa</a>-child.
\37\ See <a href="https://www.4activesystems.at/-3./">https://www.4activesystems.at/-3./</a>.
---------------------------------------------------------------------------

In the stationary pedestrian test scenario, the 4activePA-adult,
4activePA-child, and the 4activePS-child were positioned standing
upright with relaxed arms positioned vertically along the sides of the
mannequin.
NHTSA also conducted testing with the 4activePS-2YO (two-year-old
child sitting on a ``Bobby Car'' toy),\38\ the 4activePS-1YO (one-year-
old child static pedestrian) \39\ positioned in standing, sitting, and
crawling positions, and the Messring Playing Child Target (PCT--
representing a two-year-old toddler sitting on a ride-on toy car).
NHTSA evaluated the RAB system of only the Jeep Grand Cherokee L using
these pedestrian test mannequins and conditions for research purposes.
Because of the limited testing of these

[[Page 31845]]

pedestrian test mannequins and test conditions, they are not further
discussed in this request for comment notice. Details are provided in
the report added to the docket for this notice.
---------------------------------------------------------------------------

\38\ See <a href="https://www.big.de/big_en/categories/ride-on-toys/big-bobby-car/classic/big-bobby-car-classic-800001303-en.html">https://www.big.de/big_en/categories/ride-on-toys/big-bobby-car/classic/big-bobby-car-classic-800001303-en.html</a>;
Dimensions assembled (L x W x H): 58 x 30 x 38 cm.
\39\ See <a href="https://www.4activesystems.at/4activeps-1-year">https://www.4activesystems.at/4activeps-1-year</a>.
---------------------------------------------------------------------------

For the moving pedestrian test scenario, the 4activePA-adult and
the 4activePA-child were moving at a rate of five km/h perpendicular to
the backing vehicle. These test object speeds align with the testing
outlined in the 2023 Euro NCAP protocol and are representative of real-
world pedestrian walking speeds.\40\ The 4activePS-child was moving at
a rate of 3.2 km/h perpendicular to the reversing path of the vehicle.
This test object speed represents a possible real-world walking speed
of a two-year-old child.\41\ Additional test objects included a two-
year-old mannequin seated on a small ride-on ``Bobby Car'' toy, moving
laterally across the vehicle path at 3.2 km/h, and a one-year-old child
mannequin that simulated a newly mobile toddler walking or crawling at
3.2 km/h. These configurations were selected to represent realistic
backover crash scenarios involving very young children who may be
playing or moving behind a reversing vehicle.
---------------------------------------------------------------------------

\40\ Schimpl, M.; Moore, C.; Lederer, C.; Neuhaus, A.; Sambrook,
J.; Danesh, J.; Ouwehand, W.; Daumer, M., Association between
walking speed and age in healthy, free-living individuals using
mobile accelerometry--A cross-sectional study, PLoS ONE,
2011;6(8):e23299, doi: 10.1371/journal.pone.0023299, Epub 2011 Aug
10. PMID: 21853107; PMCID: PMC3154324.
\41\ Muller, Juliane, Muller, Steffen, Baur, Heiner, Mayer,
Frank, Intra-Individual Gait Speed Variability in Healthy Children
Aged 1-15 years, Gait &Posture, Vol. 38, Issue 4, pp. 631-36 (Sept.
2013).
---------------------------------------------------------------------------

The test results presented in NHTSA's 2026 Report do not show any
clear correlation between test object size and RAB system performance.
As shown below in Figure 4 and Figure 5, some vehicle RAB systems
avoided more crashes with the adult mannequin while others avoided more
crashes with the two-year-old mannequin. Figure 4 shows the results
with each mannequin for the stationary pedestrian scenario and Figure 5
shows the results with each mannequin for the moving pedestrian
scenario.
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[GRAPHIC] [TIFF OMITTED] TN28MY26.020

Figure 4. Effect of Mannequin Size in Stationary Pedestrian Scenario

[[Page 31846]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.021

Figure 5. Effect of Mannequin Size in Moving Pedestrian Scenario

6. Test Object Overlap
NHTSA performed the Reversing Vehicle--Stationary Test Object
scenario with the test objects located at three overlap percentages: 25
percent, 50 percent, and 75 percent. The percent overlap corresponds to
the location on the rear of the vehicle from the outer edge of the
vehicle's driver's door as a percentage of the vehicle's overall width.
For example, if the vehicle is 72 inches wide, the 25 percent overlap
would correspond to a point 18 inches (72 x 0.25) inboard from the
outer edge of the vehicle's driver's side. Figure 6 below shows the
overlaps graphically for an example vehicle.

[[Page 31847]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.022

Figure 6. Overlap Percentages

The results of NHTSA's stationary test object testing show that
each vehicle's RAB system had varying success at avoiding contact for
each overlap percentage, as shown in Figure 7 below.

[[Page 31848]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.023

Figure 7. Effect of Overlap in Stationary Test Object 42
---------------------------------------------------------------------------

\42\ Test objects included are as follows. Cadillac, Ford,
Subaru: Adult mannequin, 7-year-old mannequin, Standing 2-year-old
mannequin, Bollard, Pillar. Jeep: Adult mannequin, 7-year-old
mannequin, Standing 2-year-old mannequin, Standing 1-year-old
mannequin, Playing Child Target, 2-year-old mannequin on Bobby Car,
Sitting 2-year-old mannequin, Crawling 1-year-old mannequin,
Bollard, Pillar, Plastic shopping cart, Metal shopping cart, Plastic
shopping cart with adult mannequin, Metal shopping cart with adult
mannequin.
---------------------------------------------------------------------------

NHTSA also performed the moving pedestrian scenario tests at all
three overlap percentages (25 percent, 50 percent, and 75 percent). For
the moving pedestrian scenario, the test object motion was set so that
if the vehicle's brakes were not applied, the vehicle would contact the
test object at the target overlap percentage. The 25 percent overlap
represents the ``near-side'' of the vehicle in reference to the
direction the pedestrian test mannequin is approaching the vehicle's
reversing path. If the pedestrian test object is approaching the
vehicle's reversing path from the left, then 25 percent overlap is on
the near-side of the driver position. Conversely, if the pedestrian
test object is approaching the vehicle's reversing path from the right,
then 25 percent overlap is on the far-side of the driver position. As
shown below in Figure 8, vehicles' RAB systems avoided contact the most
in the 75 percent overlap test trials and avoided contact the least in
the 25 percent overlap test trials. The 50 percent overlap test trials
showed intermediate stringency, with two of the four vehicles avoiding
contact 53 percent of the time.

[[Page 31849]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.024

Figure 8. Effect of Overlap in Moving Pedestrian Scenario 43
---------------------------------------------------------------------------

\43\ Test objects included in these tests were as follows.
Cadillac, Ford, Subaru: Adult mannequin, 7-year-old mannequin,
Standing 2-year-old mannequin. Jeep: Adult mannequin, 7-year-old
mannequin, Standing 2-year-old mannequin, Standing 1-year-old
mannequin, Playing Child Target, 2-year-old mannequin on Bobby Car.
---------------------------------------------------------------------------

7. Direction of Approach
NHTSA's research also examined the effect of the direction of
pedestrian approach on RAB system performance. In the moving pedestrian
scenario, mannequins approach the vehicle's reverse path from either
the right or left, with a 50 percent overlap at the point of potential
impact. These test configurations were included to evaluate whether RAB
systems respond differently depending on which side of the vehicle a
pedestrian enters the vehicle's path.
The results from these test trials are shown in Figure 9 for the
adult mannequin and Figure 10 for the two-year-old mannequin. The
results indicate that a pedestrian's directional approach can affect
significantly RAB system response. For some vehicles, more crashes were
avoided when the pedestrian approached the vehicle's reversing path
from the right. For other vehicles, performance was better when the
pedestrian approached the vehicle's reversing path from the left. The
variability was observed across both adult and two-year-old child
pedestrian test mannequins. NHTSA seeks comment on whether there are
design reasons for performance discrepancies that depend upon the
direction of pedestrian approach.

[[Page 31850]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.025

Figure 9. Effect of Approach Direction in Moving Adult Pedestrian Test
Mannequin Test Trials

[[Page 31851]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.026

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Figure 10. Effect of Approach Direction in Moving 2-Year-Old Child
Mannequin Test Trials

C. Research Conclusions

The results of the research project indicated that while the
updated RAB test procedure was effective in providing consistent,
objective, and repeatable results, the overall performance of current
RAB systems was highly variable across vehicle models and test
conditions. The testing showed that the performance of the four RAB-
equipped vehicles using both stationary and moving pedestrian test
mannequins was inconsistent, with none of the vehicles able reliably to
avoid collisions in all moving pedestrian test conditions. Performance
also varied with vehicle reversing speeds, mannequin size, mannequin
overlap percentage, and mannequin approach direction. These findings
demonstrate that though RAB systems can prevent some backover crashes
and offer important safety benefits, current implementations do not
perform uniformly and repeatably under all conditions. These results
highlight the potential for further refinement of RAB system design to
ensure consistent pedestrian detection and braking response.

VI. Proposal in Detail

Building upon NHTSA's test results presented in NHTSA's 2026
Report, the proposed NCAP RAB pedestrian avoidance evaluation procedure
incorporates the key conditions shown to influence system performance
across vehicles. The research identified substantial variability
between vehicles when tested at different overlap percentages,
reversing speeds, pedestrian sizes, and approach directions.
Accordingly, the proposed test matrix (presented in Table 1 of the
Executive Summary section of this notice) includes both stationary and
moving pedestrian test mannequin test scenarios that systematically
vary these parameters to capture the full range of potential system
responses. This testing structure ensures that the NCAP test procedure
evaluates vehicles comprehensively and reflects real-world conditions
under which RAB systems must detect and avoid pedestrians.
A draft NCAP test procedure for evaluating RAB performance in
detecting and avoiding pedestrians is provided in the docket for this
request for comment notice. The draft test procedure includes use of a
robotic pedal controller to achieve a specific constant speed for all
test vehicles throughout a test trial and the use of a robotic steering
controller-based mannequin propulsion system for the moving pedestrian
test mannequin tests. NHTSA seeks comment on the details of this test
procedure, and whether any further test procedure clarification or
refinement is needed to facilitate objective performance evaluation of
RAB pedestrian crash avoidance.

A. Test Objects

The proposed NCAP RAB evaluation would use two pedestrian test
mannequin test objects: the 4activePA-

[[Page 31852]]

adult articulated pedestrian (adult mannequin) and the 4activePS-2YO
two-year-old child pedestrian (two-year-old mannequin).44 45
The 4activePA-adult and the 4activePS-2YO conform to the specifications
of ISO 19206-2:2018.\46\ These two mannequins represent the most common
pedestrian populations involved in backover crashes. The adult
mannequin corresponds to an articulated, full-scale representation of
an average adult. It is designed to replicate the physical dimensions,
limb articulation, and radar and optical properties of an adult
pedestrian. The adult mannequin may be used in both stationary and
moving mannequin test scenarios.
---------------------------------------------------------------------------

\44\ See <a href="https://www.4activesystems.at/4activepa">https://www.4activesystems.at/4activepa</a>.
\45\ See <a href="https://www.4activesystems.at/4activeps-2yo/">https://www.4activesystems.at/4activeps-2yo/</a>.
\46\ ``Road vehicles--Test devices for target vehicles,
vulnerable road users, and other objects, for assessment of active
safety functions--Part 2: Requirements for pedestrian targets.''
---------------------------------------------------------------------------

The two-year-old child mannequin is a smaller mannequin that
replicates the height, mass distribution, and radar and optical
signature of a standing two-year-old toddler. It can be used in both
stationary and moving mannequin tests. This mannequin size is
consistent with the physical dimensions of young children who are at
greatest risk in backover incidents. The child mannequin's standing
configuration represents a realistic scenario where a young child is
present behind a reversing vehicle, such as in a driveway or parking
lot environment.
NHTSA is proposing the use of the two-year-old child mannequin
rather than the seven-year-old child mannequin used in the 2023 Euro
NCAP protocol. In NHTSA's 2014 rear visibility final rule, NHTSA
analyzed data from FARS and CRSS during the years 2007-2011 for fatal
backover crashes.\47\ The breakdown of fatalities by age of the victim
is summarized in Table 8 and Table 9 below.
---------------------------------------------------------------------------

\47\ See 79 FR 19186 (Apr. 7, 2014), available at <a href="https://www.govinfo.gov/content/pkg/FR-2014-04-07/pdf/2014-07469.pdf">https://www.govinfo.gov/content/pkg/FR-2014-04-07/pdf/2014-07469.pdf</a>.

Table 8--All Backover Fatalities and Injuries by Age of Victim
----------------------------------------------------------------------------------------------------------------
Estimated Sample
Age of victim Fatalities Percent of Estimated percent of count of Percent of
fatalities injuries injuries injuries population
----------------------------------------------------------------------------------------------------------------
All Vehicles
----------------------------------------------------------------------------------------------------------------
Under 5........................... 84 31 1,000 6 80 7
5-10.............................. 8 3 1,000 4 50 7
10-19............................. 4 1 1,000 9 121 14
20-59............................. 73 27 7,000 49 835 55
60-69............................. 27 10 2,000 11 169 8
----------------------------------------------------------------------------------------------------------------

Table 9--Breakdown of Backover Fatalities and Injuries Involving
Passenger Vehicles for Victims Under Age 5 Years
------------------------------------------------------------------------
Percent of
Age of victim (years) fatalities
------------------------------------------------------------------------
0.......................................................... 2
1.......................................................... 59
2.......................................................... 21
3.......................................................... 11
4.......................................................... 7
------------
Total.................................................. 100
------------------------------------------------------------------------

This data indicates that children under age five represent nearly
one-third of all backover fatalities, despite making up a small share
of the population. Furthermore, the majority of backover fatalities
among children occur in the one- to two-year-old age range, while
involvement rates for children aged seven are comparatively low.\48\
Among victims under age five, approximately 59 percent were one-year-
olds and 21 percent were two-year-olds, meaning that about four out of
every five child backover fatalities occur between the ages of one and
two years. Fatalities among ages three and four were far less common,
accounting for only 18 percent combined. These data demonstrate that
the greatest risk is concentrated among toddlers, supporting the
selection of a two-year-old mannequin rather than a seven-year-old
mannequin (currently used in the 2023 Euro NCAP protocol) to represent
the most relevant and vulnerable population in RAB testing. NHTSA seeks
comment on whether the proposed adult and two-year-old mannequins are
appropriate for evaluating RAB system performance.
---------------------------------------------------------------------------

\48\ Victims that fall into the ``1-year-old'' category were 12-
to 23-months-old, and the victims in the ``2-year-old'' category
were 24- to 35-months-old.
---------------------------------------------------------------------------

B. Test Scenarios and Test Conditions

1. Stationary Pedestrian Scenario
The proposed NCAP RAB evaluation includes a series of twelve
stationary pedestrian test mannequin tests designed to assess system
performance when pedestrians are standing still within the reversing
path of the vehicle. Both the adult and two-year-old pedestrian test
mannequins will be used in these tests. For each mannequin, three
lateral overlap percentages will be used: 25 percent, 50 percent, and
75 percent. As described above, the percent overlap corresponds to the
mannequin's location as a percentage of the vehicle's overall width.
These different overlap percentages represent the potential impact
location of the pedestrian test mannequin along the rear of the vehicle
located near the left edge, center, and right edge. NHTSA's testing
presented in NHTSA's 2026 Report shows that RAB system performance
varied across these overlap percentages, with no consistent trend among
vehicles. Figure 11 illustrates this observation with data collected
for the adult mannequin and two-year-old mannequins.

[[Page 31853]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.027

Figure 11. Effect of Overlap Percentage in Test Trials With Adult and
Two-Year-Old Mannequins in Stationary Pedestrian Scenario

As shown in Figure 11, some systems performed better at detecting
pedestrians near the vehicle's centerline, while others performed
better at edge positions. This inconsistency indicates that percentage
overlap influences significantly system detection capability and
braking response. Therefore, all three overlap percentages are proposed
for the stationary mannequin test scenario to ensure symmetrical
detection performance and that the NCAP procedure evaluates system
performance over the full range of possible pedestrian locations within
a vehicle's backing path. This is important because in parking and
driveway scenarios, both directions of approach are equally likely.
Each overlap percentage will be tested at two vehicle reverse
speeds, four km/h and eight km/h, which correspond to common real-world
backing speeds in residential driveways and parking
environments.49 50 This results in six test conditions for
the adult mannequin and six for the two-year-old mannequin, for a total
of twelve stationary test conditions per vehicle. The four km/h test
speed represents slow, cautious reversing such as when a driver backs
out of a driveway, while the eight km/h speed represents situations
where a driver reverses more quickly, as backing speeds have been
documented to vary.\51\ As noted in NHTSA's 2026 Report, RAB
performance also varied by reversing speed. This variation is shown
below in Figure 12 for the adult and two-year-old mannequins.
---------------------------------------------------------------------------

\49\ Harpster, H.R. and Lemer, N., Field Measurement of
Naturalistic Backing Behavior, December 1995, DOT HS 808 532,
<a href="https://rosap.ntl.bts.gov/view/dot/2194">https://rosap.ntl.bts.gov/view/dot/2194</a>.
\50\ Mazzae, E.N., et al., ``On-Road Study of Drivers' Use of
Rearview Video System,'' September 2008, DOT HS 811 024, <a href="https://rosap.ntl.bts.gov/view/dot/63329">https://rosap.ntl.bts.gov/view/dot/63329</a>.
\51\ Mazzae, E.N., et al., ``On-Road Study of Drivers' Use of
Rearview Video System,'' September 2008, DOT HS 811 024, <a href="https://rosap.ntl.bts.gov/view/dot/63329">https://rosap.ntl.bts.gov/view/dot/63329</a>.

---------------------------------------------------------------------------

[[Page 31854]]

[GRAPHIC] [TIFF OMITTED] TN28MY26.028

Figure 12. Effect of Vehicle Speed for Adult and Two-Year-Old
Mannequins in Stationary Pedestrian Scenario

As shown in Figure 12, most systems avoided more collisions at four
km/h, but one vehicle demonstrated better performance at eight km/h. As
a result of this observed variability, both reversing speeds are
included in the proposed NCAP evaluation procedure. The multiple test
condition combinations of overlap percentages, reversing speeds, and
adult and two-year-old child pedestrian test mannequins provide a
comprehensive assessment of RAB system capability to detect stationary
adult pedestrians and small children. NHTSA seeks comment on whether
the proposed vehicle test speeds (four km/h and eight km/h) and the
three overlap percentages (25 percent, 50 percent, and 75 percent) for
the stationary adult and two-year-old mannequins are appropriate for
evaluating RAB system performance.
2. Moving Pedestrian Scenario
In addition to the twelve stationary pedestrian test mannequin test
conditions, the proposed NCAP RAB evaluation includes eight test
conditions designed to measure system performance when a pedestrian
moves laterally into the vehicle's reversing path. These test
conditions simulate a more complex real-world situation in which an
adult or child suddenly walks behind a vehicle that is already in
motion. For these test conditions, both the adult and two-year-old
mannequins will be used, each crossing at a perpendicular angle to the
vehicle's reversing path.
In the moving pedestrian scenario, all test conditions are with 50
percent overlap at the moment of potential impact. As shown in the test
results presented in NHTSA's 2026 Report (Figure 8), in the tests with
moving pedestrians, vehicles were least likely to meet the performance
criteria in the 25 percent overlap tests and more likely to meet the
performance criteria in the 75 percent overlap tests. The 50 percent
overlap is selected as an intermediate position between the 25 percent
and 75 percent overlap positions. The 50 percent overlap is also
consistent with the overlap in the 2023 Euro NCAP protocol for the
moving pedestrian test scenario.
In the moving pedestrian scenario, each mannequin starts the test
at a distance four meters from the reversing vehicle's longitudinal
centerline. Starting the mannequins at a consistent distance away from
the vehicle's centerline provides a control for how soon the vehicle's
sensors have the opportunity to detect the mannequin.
As with the stationary pedestrian scenario, each mannequin will be
tested at both vehicle reversing speeds of four km/h and eight km/h.
Figure 13 shows RAB performance variation based on reversing speed with
a moving adult and two-year-old mannequins. Two vehicle models
performed better at the

[[Page 31855]]

higher vehicle reversing speed while the other two vehicles performed
better at the lower reversing speed. This RAB performance variation
indicates the need to test at both reversing speeds of four and eight
km/h to assess system performance fully.
[GRAPHIC] [TIFF OMITTED] TN28MY26.029

Figure 13. Effect of Vehicle Speed for Adult and Two-Year-Old
Mannequins in Moving Pedestrian Scenario

In the moving pedestrian scenario, the mannequins will also move at
a prescribed lateral speed perpendicular to the reversing path of the
vehicle. The adult mannequin moves at a speed of five km/h which
represents a brisk walking pace of an average adult,52 53
and is consistent with the established test procedure in the 2023 Euro
NCAP protocol. The two-year-old mannequin moves at 3.2 km/h. This
introduces a new speed not found in the 2023 Euro NCAP protocol, but
the use of 3.2 km/h is necessary to correspond accurately to a
toddler's slower walking speed 54 55 compared to an adult.
The testing results presented in NHTSA's 2026 Report demonstrate that
RAB systems often responded differently to moving adult and child
mannequins (see Figure 5). This inconsistency in performance across
vehicle models and crossing conditions supports the need to evaluate
both pedestrian sizes for the moving pedestrian scenario to ensure the
testing evaluates potential limitations in system sensitivity and
recognition.
---------------------------------------------------------------------------

\52\ Oberg T., Karsznia A., Oberg K. Basic gait parameters:
reference data for normal subjects, 10-79 years of age. J Rehabil
Res Dev. 30(2):210-23 (1993)' PMID: 8035350.
\53\ Schimpl, M.; Moore, C.; Lederer, C.; Neuhaus, A.; Sambrook,
J.; Danesh, J.; Ouwehand, W.; Daumer, M. Association between walking
speed and age in healthy, free-living individuals using mobile
accelerometry--A cross-sectional study. PLoS ONE, 6(8):e23299
(2011); doi: 10.1371/journal.pone.0023299; Epub 2011 Aug 10; PMID:
21853107; PMCID: PMC3154324.
\54\ Cavagna GA., Franzetti P., Fuchimoto T. The mechanics of
walking in children, J Physiol343:323-39 (Oct. 1983); doi: 10.1113/
jphysiol.1983.sp014895; PMID: 6644619; PMCID: PMC1193922.
\55\ Muller, Juliane, Muller, Steffen, Baur, Heiner, Mayer,
Frank, Intra-Individual Gait Speed Variability in Healthy Children
Aged 1-15 years, Gait &Posture, Vol. 38, Issue 4, pp. 631-636 (Sept.
2013).
---------------------------------------------------------------------------

Two separate tests will be conducted for each combination of
mannequin size (two-year-old or adult) and vehicle reversing speed
(four km/h or eight km/h). One test will be conducted with the
mannequin approaching from the right with respect to the vehicle's
reversing path, and another test will be conducted with the mannequin
approaching from the left. This will allow NHTSA to evaluate system
performance for situations where a pedestrian is approaching either
from the right or

[[Page 31856]]

from the left, which are equal possibilities in a parking lot or
driveway scenario. The test results presented in NHTSA's 2026 Report
also indicate that vehicle performance can differ depending on the
approach direction of the mannequin, with some systems responding
earlier or more effectively when the mannequin entered from one side
compared to the other (see Figure 9 and Figure 10). Therefore, it is
important to assess both pedestrian approach directions to provide a
complete evaluation of RAB system performance.
NHTSA seeks comment on the proposed moving pedestrian test
mannequin test scenario for evaluating RAB system performance.
Specifically, NHTSA seeks comment on the proposed vehicle speed (four
km/h and eight km/h), lower speed of 3.2 km/h for the two-year-old
mannequin compared to the five km/h for the adult mannequin, and
mannequin approach directions (left and right) with respect to the
vehicle's reversing path. NHTSA also seeks comment on whether to add
the 25 percent overlap location to the moving pedestrian scenario,
which is more stringent than the 50 percent overlap location as shown
in Figure 8 for the tests conducted on four MY 2022 vehicles.
The proposed stationary and moving pedestrian test mannequin test
scenarios for evaluating RAB system performance are to be conducted
exclusively in daylight. While RAB system performance differed across
lighting conditions in recent research tests, vehicles generally
avoided more collisions with the pedestrian test mannequins in daylight
than in darkness. NHTSA seeks comment on whether the proposed RAB
evaluation protocol should include testing in darkness, or whether
darkness testing should be considered for inclusion in NCAP at a later
date.

C. Pass-Fail Criteria

A vehicle will be considered to have met the NCAP RAB performance
requirement only if it satisfies all performance criteria for every one
of the 20 test conditions described above (12 stationary pedestrian
test mannequin test conditions and eight moving pedestrian test
mannequin test conditions). Vehicles that meet the criteria in full
will receive a check mark indicating successful RAB system performance
under NCAP. The performance criteria are as follows:
First, an auditory warning must sound prior to the onset of the
vehicle's RAB system providing automatic braking. This requirement
ensures that the RAB system provides the driver with a clear and timely
warning to the presence of a pedestrian, providing situational
awareness and allowing for potential manual intervention by the driver.
Second, the vehicle must not make physical contact with any test
object during any test trial. Successful avoidance of contact
demonstrates that the RAB system effectively detects the pedestrian
test mannequin and applies sufficient braking force to bring the
vehicle to a stop before impact.
Third, once automatic braking has been initiated and the vehicle
comes to a complete stop, the vehicle's brakes must remain engaged
until either: (1) the pedestrian test mannequin is no longer in the
vehicle's path, or (2) the driver performs a deliberate override
action. Some RAB systems bring the vehicle to a stop but then release
the brakes. This provision addresses premature brake release that could
otherwise result in secondary contact or incomplete system
intervention. NHTSA has not defined ``deliberate override action'' at
this time to provide system design flexibility. NHTSA seeks comment on
whether permitted override action(s) should be defined and if so, what
would be the definition(s).
Finally, the RAB system must be configured such that it defaults to
``ON'' at the start of each ignition or key cycle. This requirement
aligns with the 2023 Euro NCAP protocol requirements and ensures that
the system cannot be disabled by default, thereby providing continuous
protection each time the vehicle is used.
NHTSA seeks comment on the four proposed performance criteria for
evaluating RAB system performance: (1) an auditory warning shall be
provided prior to RAB system brake application onset; (2) the vehicle
shall not contact the pedestrian test mannequin; (3) after the vehicle
comes to a complete stop, its brakes shall not be released unless the
pedestrian test mannequin is no longer in the vehicle's path or the
driver performs a deliberate override action; and (4) the RAB system
shall default to ``ON'' after each ignition/key cycle. NHTSA also seeks
comment on the effectiveness of different RAB system warning
strategies, whether a haptic warning signal should be permitted in lieu
of an auditory warning, and whether a visual warning should also be
required.

D. Number of Trials per Test Condition

NHTSA proposes to perform one trial per RAB test condition. In the
stationary mannequin scenario, there are 12 test conditions (two
vehicle speeds (four and eight km/h) x two mannequins (adult and two-
year-old) x three overlap percentages (25 percent, 50 percent, and 75
percent)). For the moving mannequin scenario, there are eight test
conditions (two vehicle speeds (four and eight km/h) x two mannequins
(adult and two-year-old) x two approach directions (left and right of
vehicle). Conducting one trial per test condition results in a total of
20 tests for evaluating RAB performance, as shown in Table 1.
Conducting one trial per test condition is similar to the approach
NHTSA is using to assess other ADAS technologies added to NCAP in
2024.\56\
---------------------------------------------------------------------------

\56\ 89 FR 95916. The December 3, 2024 final decision notice
added four new ADAS technologies--blind spot warning, blind spot
intervention, lane keeping assist, and pedestrian automatic
emergency braking to NCAP.
---------------------------------------------------------------------------

NHTSA also proposes that, in the process of conducting the RAB
tests, if the test vehicle does not meet all four proposed performance
criteria in a test, then any remaining tests (of the 20 proposed
scenarios) with the vehicle will not be conducted because the vehicle
would not be receiving NCAP credit for RAB.
NHTSA seeks comment on the proposal to conduct only one trial per
test condition and to not conduct any remaining tests if the vehicle
fails to meet all four performance criteria during a test trial.

E. Awarding Credit for RAB Systems

NHTSA proposes to denote vehicles that are equipped with RAB and
that meet the proposed performance criteria for all 20 proposed RAB
test conditions with a check mark on NHTSA's website. This is similar
to the approach the Agency is using to notify consumers on available
ADAS technologies that meet NHTSA's performance criteria.\57\ Until a
crash avoidance rating system is developed and implemented, the check
mark on the NHTSA website will remain the primary way of notifying
consumers of available ADAS technologies meeting NHTSA's system
performance criteria.\58\
---------------------------------------------------------------------------

\57\ 89 FR 95916.
\58\ Euro NCAP currently assesses RAB performance as part of its
Vulnerable Road User Protection program. See <a href="https://www.euroncap.com/media/79885/euro-ncap-assessment-protocol-vru-v114.pdf">https://www.euroncap.com/media/79885/euro-ncap-assessment-protocol-vru-v114.pdf</a>. Euro NCAP allocates points for daytime testing in each
pedestrian automatic emergency braking (PAEB) test scenario which
includes potential frontal and rear impact scenarios involving
pedestrians. The total points for RAB credits represent 33 percent
of daytime PAEB points allocated in Euro NCAP.
---------------------------------------------------------------------------

Among the four MY 2022 vehicles tested (2022 Cadillac XT4, 2022
Ford Mustang Mach-E, 2022 Jeep Grand Cherokee L, and 2022 Subaru
Outback Touring), results suggest that while some RAB systems performed

[[Page 31857]]

significantly better than others, none of the vehicle models tested
would obtain credit for RAB as proposed in this RFC.
NHTSA requests comment on the proposal to give credit for RAB
systems only when the vehicle meets the performance criteria for all 20
test conditions.

VII. Conclusion

This RFC proposes to implement an RAB testing program in NHTSA's
NCAP. In doing so, it responds to the need for improved protection of
vulnerable road users such as small children in backover crash
scenarios. This RFC seeks public comment on a proposed program that
would evaluate RAB system performance using standardized, objective
test procedures. If implemented, the changes to NCAP proposed in this
document would advance NHTSA's efforts to provide consumers with
important safety information regarding technologies designed to prevent
backover crashes and reduce injuries and fatalities to pedestrians.

VIII. Economic Analysis

The changes to NCAP proposed in this RFC ultimately would enable a
rating system that improves consumer awareness of pedestrian protection
systems and the improvements to safety that stem from those systems. It
would also encourage manufacturers to accelerate RAB adoption. The
accelerated adoption of pedestrian protection systems would drive any
economic and societal impacts that result from these changes and are
thus the focus of this discussion of economic analysis. Hence, NHTSA
has considered the potential economic effects for rear automatic
braking pedestrian protection system proposed for inclusion in NCAP and
the potential benefit of eventually developing a new rating system that
would include this information.
RAB systems have the potential to reduce crashes with pedestrians
when the vehicle is traveling in reverse. While NHTSA's research on RAB
systems has been limited to only certain vehicle models, it illustrates
how these systems can provide safety benefits. Though NHTSA does not
have sufficient data to determine the monetized safety impacts
resulting from RAB systems, NHTSA expects that the proposed inclusion
of RAB systems in NCAP would likely have positive safety effects by
promoting earlier and more widespread deployment of these technologies
as well as encouraging manufacturers to design RAB systems with the
ability to detect and avoid pedestrians consistently when the vehicle
is reversing.
NCAP helps address the issue of asymmetric information (i.e., when
one party in a transaction is in possession of more information than
the other), which can be considered a market failure. Regarding
consumer information, the introduction of a potential new component to
the NCAP rating system is anticipated to provide consumers additional
vehicle safety information regarding the safety of vulnerable road
users to help them make more informed purchasing decisions by
presenting the relative safety benefits of systems designed to protect
not only occupants inside the vehicle but also persons outside the
vehicle. While NHTSA knows that consumers value information about the
protection of vehicle occupants when making purchasing decisions, NHTSA
believes that, as a society, most consumers are also interested in
protecting people that share their roads. Hence, there is an
unquantifiable value to consumers and to society as a whole for NHTSA
to provide accurate and comparable vehicle safety information about
protecting all lives. At this time, NHTSA does not have sufficient
data, such as unit cost and information on how soon the full adoption
of RAB systems designed to detect and avoid pedestrians would be
reached, to predict the net increase in cost to consumers with a high
degree of certainty.

IX. Public Participation

Interested parties are encouraged to submit thorough and detailed
comments relating to each of the relevant areas discussed in this
notice. Please see Appendix A for a summarized list of specific
questions that have been posed in this notice. Comments submitted will
help NHTSA make informed decisions as it strives to advance NCAP by
encouraging continuous safety improvements for new vehicles and
enhancing consumer information.

How do I prepare and submit comments?

Your comments must be written and in English. To ensure that your
comments are correctly filed in the Docket, please include the docket
number indicated in this document in your comments.
Your comments must not be more than 15 pages long (49 CFR 553.21).
NHTSA established this limit to encourage you to write your primary
comments in a concise fashion. However, you may attach necessary
additional documents to your comments. There is no limit on the length
of the attachments.
If you are submitting comments electronically as a PDF (Adobe)
file, NHTSA asks that the documents submitted be scanned using an
Optical Character Recognition (OCR) process, thus allowing NHTSA to
search and copy certain portions of your submissions.
Please note that pursuant to the Data Quality Act, in order for
substantive data to be relied upon and used by the Agency, it must meet
the information quality standards set forth in the OMB and DOT Data
Quality Act guidelines. Accordingly, we encourage you to consult the
guidelines in preparing your comments. OMB's guidelines may be accessed
at <a href="https://www.transportation.gov/regulations/dot-information-dissemination-quality-guidelines">https://www.transportation.gov/regulations/dot-information-dissemination-quality-guidelines</a>.

How do I submit confidential business information?

You should submit a redacted ``public version'' of your comment
(including redacted versions of any additional documents or
attachments) to the docket using any of the methods identified under
ADDRESSES. This ``public version'' of your comment should contain only
the portions for which no claim of confidential treatment is made and
from which those portions for which confidential treatment is claimed
has been redacted. See below for further instructions on how to do
this.
You also need to submit a request for confidential treatment
directly to the Office of Chief Counsel. Requests for confidential
treatment are governed by 49 CFR part 512. Your request must set forth
the information specified in part 512. This includes the materials for
which confidentiality is being requested (as explained in more detail
below); supporting information, pursuant to section 512.8; and a
certificate, pursuant to section 512.4(b) and part 512, Appendix A.
You are required to submit to the Office of the Chief Counsel one
unredacted ``confidential version'' of the information for which you
are seeking confidential treatment. Pursuant to section 512.6, the
words ``ENTIRE PAGE CONFIDENTIAL BUSINESS INFORMATION'' or
``CONFIDENTIAL BUSINESS INFORMATION CONTAINED WITHIN BRACKETS'' (as
applicable) must appear at the top of each page containing information
claimed to be confidential. In the latter situation, where not all
information on the page is claimed to be confidential, identify each
item of information for

[[Page 31858]]

which confidentiality is requested within brackets: ``[ ].''
You are also required to submit to the Office of the Chief Counsel
one redacted ``public version'' of the information for which you are
seeking confidential treatment. Pursuant to section 512.5(a)(2), the
redacted ``public version'' should include redactions of any
information for which you are seeking confidential treatment (i.e., the
only information that should be unredacted is information for which you
are not seeking confidential treatment).
NHTSA is currently treating electronic submission as an acceptable
method for submitting confidential business information to the Agency
under part 512. Please do not send a hard copy of a request for
confidential treatment to NHTSA's headquarters. The request should be
sent to Dan Rabinovitz in the Office of the Chief Counsel at
<a href="/cdn-cgi/l/email-protection#7531141b1c10195b2714171c1b1a031c010f35111a015b121a03">[email&#160;protected]</a> or you may contact him for a secure file
transfer link. Manufacturers or any companies that already have a
Confidential Business Information (CBI) Portal account or an Enterprise
Account with NHTSA should use the CBI Portal for their submission. If
you are submitting a CBI request, please also email a courtesy copy of
the request to John Piazza at <a href="/cdn-cgi/l/email-protection#23494c4b4d0d534a4259594263474c570d444c55">[email&#160;protected]</a>.

Will the Agency consider late comments?

NHTSA will consider all comments received before the close of
business on the comment closing date indicated above under DATES. To
the extent possible, NHTSA will also consider comments that the docket
receives after that date. If the docket receives a comment too late for
us to consider in developing a final decision (assuming that one is
issued), NHTSA will consider that comment as an informal suggestion for
future NCAP updates.

X. Appendices

A. Requests for Comment

[1] NHTSA seeks comment on whether the inclusion of RAB technology
in NCAP is appropriate.
[2] NHTSA seeks information regarding the motivation for the
changes in RAB test scenarios between the 2023 Euro NCAP Protocol (Test
Protocol--AEB/LSS VRU Systems; Implementation 2023, Version 4.5.1,
February 2024) and the October 2025 Euro NCAP Protocol, ``Crash
Avoidance Low Speed Conditions Protocol, Version 1.1 October 2025,
Implementation January 2026.''
[3] A draft NCAP test procedure for evaluating RAB is provided in
the docket for this request for comment notice. NHTSA seeks comment on
the details of this test procedure, and whether any further test
procedure clarification or refinement is needed to facilitate objective
performance evaluation of RAB pedestrian crash avoidance.
[4] NHTSA seeks comment on whether the proposed adult and two-year-
old mannequins are appropriate for evaluating RAB system performance.
[5] NHTSA seeks comment on whether the proposed vehicle test speeds
(four km/h and eight km/h) and the three overlap percentages (25
percent, 50 percent, and 75 percent) for the stationary adult and two-
year-old mannequins are appropriate for evaluating RAB system
performance.
[6] NHTSA seeks comment on the proposed moving mannequin test
scenario for evaluating RAB system performance. Specifically, NHTSA
seeks comment on the proposed vehicle speed (four km/h and eight km/h),
lower speed of 3.2 km/h for the two-year-old mannequin compared to the
five km/h for the adult mannequin, and mannequin approach directions
(left and right) with respect to the vehicle's reversing path.
[7] NHTSA also seeks comment on whether to add the 25 percent
overlap location to the moving pedestrian scenario, which is more
stringent than the 50 percent overlap location as shown in Figure 8 for
the tests conducted on four MY 2022 vehicles.
[8] The proposed stationary and moving pedestrian test mannequin
test scenarios for evaluating RAB system performance are to be
conducted exclusively in daylight. While RAB system performance
differed across lighting conditions in recent research tests, vehicles
generally avoided more collisions with the pedestrian test mannequins
in daylight than in darkness. NHTSA seeks comment on whether the
proposed RAB evaluation protocol should include testing in darkness, or
whether darkness testing should be considered for inclusion in NCAP at
a later date.
[9] NHTSA has not defined ``deliberate override action'' at this
time to provide system design flexibility. NHTSA seeks comment on
whether permitted override action(s) should be defined and if so, what
would be the definition(s).
[10] NHTSA seeks comment on the four proposed performance criteria
for evaluating RAB system performance: (1) an auditory warning shall be
provided prior to RAB system brake application onset; (2) the vehicle
shall not contact the pedestrian test mannequin; (3) after the vehicle
comes to a complete stop, its brakes shall not be released unless the
pedestrian test mannequin is no longer in the vehicle's path or the
driver performs a deliberate override action; and (4) the RAB system
shall default to ``ON'' after each ignition/key cycle. NHTSA also seeks
comment on the effectiveness of different RAB system warning
strategies, whether a haptic warning signal should be permitted in lieu
of an auditory warning, and whether a visual warning should also be
required.
[11] NHTSA seeks comment on the proposal to conduct only one trial
per test condition and to not conduct any remaining tests if the
vehicle fails to meet all four performance criteria during a test
trial.
[12] NHTSA requests comment on the proposal to give credit for RAB
systems only when the vehicle meets the performance criteria for all 20
test conditions.

Issued under authority delegated in 49 CFR 1.95.
Jonathan Morrison,
Administrator.
[FR Doc. 2026-10611 Filed 5-27-26; 8:45 am]
BILLING CODE 4910-59-P

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