Research progress on passive safety standards for smart vehicles

In order to solve the problem of existing passive safety-related standards restricting the development of new smart car technologies, a plan for the construction of China's smart car passive safety standard evaluation system was formulated based on the revision work and content of smart car passive safety-related standards by international standards organizations and American standards agencies. and China’s smart vehicle passive safety standard development roadmap, and uses a national mandatory standard as an example to provide necessary support for the applicability of China’s passive safety standards in formulating and revising them.

1 Introduction

With the revolutionary wave of artificial intelligence and the new generation of information and communication technology , automobiles, as one of the best carriers for the integrated application of new technologies, are accelerating their transformation to intelligence. Smart cars have become the strategic direction and focus of competition for the development of the international automobile industry [1- 4].

In order to avoid existing standards restricting the development of new technologies, this article combines the working principles and methods of the International Standards Organization and the American Standards Agency on the revision of standards related to passive safety of smart cars, and carries out the construction plan of the passive safety standard evaluation system for Chinese smart cars and the development plan of the Chinese smart car passive safety standards. Research work on the development route of passive safety standards, and conducted preliminary research on the revision of passive safety related standards.

2 Research progress on foreign standards related to passive safety of smart vehicles

2.1 US NHTSA’s revised principles and scope for smart car passive safety related standards

The United States has systematically scanned existing passive safety standards in the United States since 2016 in order to deal with conflicts and impacts brought about by the development of smart car technology [5]. The U.S. Highway Traffic Safety Administration ( NHTSA )  released  testable cases and scenario frameworks for smart car driving systems on September 28, 2018 [6 ] , and on May 28, 2019 Advance Notice of Proposed Rule Making (ANPRM) was released to solve the problem of the impact of the development of future smart cars on crash safety performance [7-8]. To address issues with the design of new vehicles (particularly non-passenger vehicles or vehicles with significant modifications to the driver's position and control), NHTSA issued a proposed rulemaking on March 30, 2020, which revised several Crashworthiness regulations to clarify safety standards for motor vehicles without driver control [9]. On January 13, 2021, NHTSA launched the final version of the proposal, which eliminates major and unnecessary regulatory obstacles and paves the way for the production, sale and use of smart cars in the future [10-11]. On March 10, 2022, NHT⁃SA published a final rule that updates the Occupant Protection Federal Motor Vehicle Safety Standard to ensure the safety of autonomous vehicle occupants.

2.1.1 NHTSA’s revised principles for smart car passive safety standards

First, it is necessary to maintain the same occupant protection performance of smart cars and traditional cars; second, remove the requirements that may arise from the development of smart cars that do not require supervision; third, the revised requirements are beneficial to those equipped with smart car technology. vehicles, and does not change the requirements for non-smart vehicles; finally, the requirements are revised to remain technology neutral, i.e. neither tilted towards active safety, in line with the principles outlined in the U.S. Department of Transportation guidance Preparing for the Future of Transportation: Autonomous Vehicles 3.0 It is also not inclined to modify the U.S. Federal Motor Vehicle Safety Standard (FMVSS) in a passive safety manner, and to modify the FMVSS in a way that better reflects some innovative interiors.

2.1.2 Prerequisites for NHTSA’s revision of standards related to passive safety of smart vehicles

a. Assuming that the smart car seat layout is the same as that of traditional vehicles, other forms of seat layout require further research.

b. The crash safety requirements are revised for vehicles that only carry cargo (no/little passengers), but their compatibility issues are not considered.

c. The revision is limited to the 200 series FMVSS and does not apply to the 300 series standards. The requirements related to signaling devices and warnings are not modified because this area has implications beyond the 200 Series standards and is the subject of continued study by NHTSA. However, modifications to the airbag suppression signal device are planned to be announced separately in the future.

2.1.3 Scope of NHTSA’s revision of standards related to passive safety of smart cars

Revised for use without a driver's seat but with multiple front passenger seats. It is recommended that the front airbag indicator light and suppression device be displayed separately and be visible from every front seat.

Seat belt requirements have been revised for medium-sized buses (curb weight 4 536 to 11 793 kg) and school buses (curb mass greater than 4 536 kg). For the situation where smart cars do not have a driver, it is recommended that the front seats of the vehicle meet the requirements of the driver. Same requirements for seats.

When the vehicle does not have a steering wheel and steering device, FMVSS 203 and FMVSS 204 will not be applicable to the evaluation of smart cars. It is recommended that the occupant protection standard not apply to vehicles used solely to carry cargo ("occupantless" vehicles), a requirement that could be accomplished by modifying the scope of application to indicate that the standard applies only to "trucks" with a driver.

NHTSA revised FMVSS 201, FMVSS 205, FMVSS 206, FMVSS 207, FMVSS 208, FMVSS 214, FMVSS 216, and FMVSS 226.

2.2 WP.29 Passive Safety Working Group’s scope of revision of standards related to passive safety of smart cars

At the 71st session of the Working Party on Passive Safety (G RS P) of the World Forum for the Harmonization of Vehicle Regulations ( WP.29) on May 10, 2022 A research working group on the coordination of passive safety standards and smart car-related functions was established to study the current passive safety-related United Nations Economic Commission for Europe automotive regulations (the regulation of Economic Commission of Europe, ECE) and Global Technical Regulation (Global Technical  Regulation ) , GTR) standard and the compatibility issues with future smart car technology in order to promote the reasonable development of passive safety performance of smart cars [12].

This work is currently in its early stages, and the list of major relevant ECE and GTR passive safety international standards involved is shown in Table 1.

Table 1 Main relevant international standards for ECE passive safety

3 Research progress on domestic smart vehicle passive safety related standards

3.1 Development status of smart car standards and national mandatory standards for passive safety

In recent years, China's smart car production has grown rapidly, and technology that combines active safety and passive safety has also made certain developments. The planning and development of automobile safety technology has led to the formulation and upgrading of active safety and passive safety standards [13-15].

Smart car standards are mainly organized and formulated by the National Technical Committee of Auto Standardization (SAC/TC114). The standards are divided into basic, general specifications, product and technology applications, resource management and information services, and related standards. So far, 12 smart car standards have been released, and another 26 standards are under research, project approval or to be released. The standard is mainly based on the agreement on the technical functions and performance of smart vehicles in terms of functional safety, information security, network security and human-computer interaction, and does not require the protection performance of vehicle occupants.

Automobile passive safety standards are mainly organized and formulated by the Automobile Crash Test and Crash Protection Sub-Technical Committee SAC/TC114/SC33 of the National Automotive Standardization Technical Committee. Currently, 96 mandatory national standards for automobiles have been approved and released, including 28 automobile passive safety standards, accounting for 29%, as shown in Table 2. The standards mainly focus on the performance requirements for the entire vehicle and its components during a collision, as well as the protection requirements for the occupants in the vehicle. They do not specify the impact of new smart car functions and components on occupant injuries.

Table 2 National mandatory standards for passive safety

Smart vehicle active safety functions and components (such as automatic emergency braking functions) completely change the movement posture and position of vehicle occupants in the event of a collision. Traditional passive safety systems will not be able to correctly minimize occupant injuries; in addition, in the future, there will be no When the driver or vehicle occupants' riding posture changes, there will be conflicts in technology and product performance requirements in the current standards. In order to prevent the content of current national standards from restricting the development and progress of advanced technologies, it is necessary to systematically scan the technical content of current national standards and put forward corresponding modification suggestions to promote the reasonable and orderly development of the automotive industry.

3.2 Construction Plan of China Smart Vehicle Passive Safety Standard Evaluation System

Combined with the current development trend of smart car technology and the revision process of standards related to passive safety of smart cars by relevant countries and international standards organizations, based on the content and revision direction of the standard, it is necessary to ensure that vehicles equipped with smart car technology are beneficial and do not change the requirements for non-smart cars. On the basis of this, a construction plan for the passive safety standard system of China’s smart vehicles has been initially established.