Consideration of Steering Method Control Based on Driving Situations

Proportional Derivative (PD) steering assistance offers potential measures by which the control stability of a vehicle can be rapidly improved. However, for all Proportional Derivative (PD) steering methods, the inconvenience caused by the need to keep turning the steering wheel during cornering is significant. Because the steering return phenomenon of the steering wheel stop like this is not so preferable, it is preferable that the Proportional Derivative (PD) steering assistance is extremely weak (almost 0) in such a usual grip cornering driving. Alternatively, in the drift area of cornering where the grip area of the tires has been exceeded, Proportional Derivative (PD) steering assistance is helpful because the driver can control his counter steering extremely well. Furthermore, only a small amount of Proportional Derivative (PD) steering assistance is required in the drift area. And, because the amount of Proportional Derivative (PD) steering assistance required is minor, there is little in the way of control disconnection sensation during the transition from grip cornering to drift cornering. Moreover, because the response and settling of a vehicle shows strong improvement when Proportional Derivative (PD) steering assistance is used during lane changes, use of the technique is preferable at that time. In this background, steering method controls into which the Proportional Derivative (PD) steering assistance constant has been applied, along with perception changes in anticipated driving situations was examined.