Improvement in Steering Performance by Push-Pull Operation in Car Driving

Abstract

Collision avoidance is one of the most difficult driving operations in the domain of intelligent vehicles. Steering operation error is one of the causes of traffic accidents. Steering operability also contributes greatly to the comfort of drivers and their mental workload during driving. Thus, with comfortable steering operation it is possible to reduce shoulder stiffness and arm fatigue caused by long-time driving. The development of automatic driving vehicles is becoming advanced worldwide. Consequently, the goal is to implement a level 3 automatic driving vehicle for practical use, in which "the system performs the acceleration, the steering, and the braking, and the driver responds when the system requests it". For this system to be practical, when autonomous driving becomes impossible for some reason, it is important to develop a system that allows the driver to be in control regardless of driving experience or age. In conventional round steering wheel, since there is no output muscle directly involved in the direction of movement of the upper limbs, it is difficult to instantaneously exert a large force and control performance is not good. Therefore, a twin lever steering (TLS), which is a push / pull alternate steering system, is proposed in this study. In the proposed TLS, there are output muscles that are directly involved in the direction of movement of the upper limb, including the biceps brachii muscle, and it is conceivable that the motor controllability is higher than in the conventional system. In this research, the superiority of the proposed TLS was verified using an experimental racing kart and driving simulator (DS). Furthermore, using DS, the superiority of a TLS in the steering operation immediately after the cancellation of automatic operation is clear.

Straight Path Handling Anomalies of Passenger Cars Induced by Suspension Component and Assembly Tolerances

“…Clearly, these issues also have an impact on the design of control systems, such as active front steering control [13], as well as on steering performance of classes of vehicles, like autonomous drive vehicles [14] and ultra-light cars [15]. The present contribution is focused on understanding which is the causes and on reducing the extents of PTS, SWM and DL as handling anomalies due to suspension component and assembly tolerances, in the specific case of vehicles with front Double wishbone suspension and rear Five arms suspension.…”