The ever-increasing complexity and connectivity of driver assist functions pose challenges for both Functional Safety and Cyber Security. Several of these challenges arise not only due to the new functionalities themselves but due to numerous interdependencies between safety and security. Safety and security goals can conflict, safety mechanisms might be intentionally triggered by attackers to impact functionality negatively, or mechanisms can compete for limited resources like processing power or memory to name just some conflict potentials. But there is also the potential for synergies, both in the implementation as well as during the development. For example, both disciplines require mechanisms to check data integrity, are concerned with freedom from interference and require architecture based analyses. So far there is no consensus in the industry on how to best deal with these interdependencies in automotive development projects. SAE J3061 introduces a process framework for Cyber Security development that is intentionally very similar to that for Functional Safety as defined in ISO 26262. While these parallel frameworks help to identify interdependencies and show that aligned processes are possible, a joint process seems unreasonable due to the vastly different implementation frameworks and methods. Using concrete examples, we show problems that can arise if Functional Safety and Cyber Security processes are not properly aligned and integrated into the overall development process. Based on this we then propose steps towards coordinated safety and security processes that can prevent such problems and show how such an approach at the same time allows to benefit from synergies.

von Wedel, Jana Karina, Arndt, Paul

Control of Steer by Wire System for Reference Steering Wheel Torque Tracking and Return-Ability

2018-01-05664/3/2018

This paper proposes a torque tracking algorithm via steer by wire to achieve the target steering feel and proposed a modified friction model to obtain return-ability. A three dimensional reference steering wheel torque map is designed using the measurement data of the steering characteristics of the target vehicle at a transition test and a weave test. In order to track the reference steering wheel torque, a sliding mode control is used in the tracking algorithm. In addition, to achieve return-ability, the modified friction model for steer by wire is used instead of the friction model defined in the reference steering wheel torque map. The modified friction model is composed of various models according to the angular velocity. The angular velocity and the angular acceleration used in the control algorithm are estimated using a kalman filter. A motor is used as the actuators to generate the targeted steering feel and the torque angle sensor (TAS) is used to measure the steering wheel torque and the steering wheel angle. Using the computer simulations, the return-ability of the proposed controller was evaluated with the return test and the tracking performance of the proposed controller was evaluated with the weave test and transition test. By using this proposed control algorithm in steer by wire system, the steering feel close to that of a conventional motor driven steer system has been successful obtained and return-ability has been achieved.

Lee, Jaepoong, kyongsu, Yi, Kim, Kwangil, Lee, Byungrim, Lee, Dongpil, Jang, Bongchoon, Chang, Sehyun

2021-12-29.TEST Development of Autonomous Driving System Using GNSS and High Definition Map

2018-01-0036

4/3/2018

Recently, development of vehicle control system targeting Full Driving Automation (autonomous driving level 5) has advanced. Some applications of autonomous driving systems like the Lane Keeping Assist system (LKA) and Auto Lane Change system (ALC) (autonomous driving level 1-3) have been put on the market. However, the conventional system using information from front camera, it is difficult to operate in some situations. For example the road that no line, large curvature and number of lane increases or decreases. We propose an autonomous driving system using high accuracy vehicle position estimation technology and a high definition map. An LKA system calculates the target steering wheel angle based on both vehicle position information from the Global Navigation Satellite System (GNSS) and the target lane of high the definition map, according to the method of front gaze driver model. Then, the system controls steering the wheel angle by Electric Power Steering (EPS). In the case of ALC, a target lane-change path is generated based on information of the vehicle’s own lane and the next one. The proposed system solved the problem of the conventional method. Moreover, the developed method can operate more smoothly than the conventional one. Finally, we demonstrate that the proposed system enables the actual vehicle to operate LKA and ALC in the merged road of a test tracks.

Takeuchi, Yu, Hideyuki, Tanaka, Kazuo, Hitosugi, Tomoki, Uno