Abstract: With the improvement of commercial vehicle autonomous driving level, the safety of the active steering function of the steering system is increasingly valued. The electric-hydraulic steering system is currently an ideal solution for the steering electrification and intelligence of medium and heavy commercial vehicle. This paper proposes a high safety electric-hydraulic steering system with an electrical redundancy architecture, and designs the most critical sensor safety mechanism from the perspective of functional safety. Precisely, redundancy verification and online monitoring of failure modes are carried out on the torque signal, and the absolute angle values converted by the steering wheel by the two angle acquisition modules and motor position sensors are analyzed for correctness verification and multiple fault tolerance judgments. Finally, the hardware-in-the-loop(HIL) test is carried out to verify the effectiveness of the designed sensor safety mechanism.

Key words: Commercial vehicle; Electric-hydraulic steering system; Redundant design; Sensor; Safety mechanism

摘要： 随着商用车自动驾驶技术的发展，对转向系统的主动转向功能的安全性愈加重视，电 液复合转向系统是现阶段解决中重型商用车转向电动化和智能化的理想方案。文章提出了一 种高安全性的双电机电液复合转向系统电气冗余架构，并从功能安全角度出发对最为关键的 传感器安全机制进行设计，分别对转矩信号进行冗余校验和失效模式在线监控，对两个转角 采集模块解析出转向盘以及电机位置传感器折算的绝对转角值进行正确性校验和多重容错判 断，最后进行了硬件在环台架（HIL）测试，验证了所设计传感器安全机制的有效性。

关键词: 商用车；电液复合转向系统；冗余设计；传感器；安全机制