Application of Self-Tuning to Automotive Cruise Control

This paper presents an application of a self-tuning method to an automotive cruise control. Auto cruise controls are widely used today for their convenience, but as the vehicles incorporating these controls become more numerous and diverse, load matching makes for problems. This is why the practical realization of a self-tuning system not requiring this matching is needed. We adopted a self-tuning approach using the recursive least-squares method to identify a vehicle model and the pole assignment to obtain the feedback gains. The reason for this adaptive control approach is that the designer can express the control specifications for the automotive cruise control system through pole designation and thereby achieve a comfortable ride. Also, safety is a prerequisite for any automotive speed control system, and with this indirect adaptive control the advantage is that vehicle parameter variation can be consistently monitored, allowing one to pinpoint any trouble immediately and take appropriate measures. We performed simulation and actual road tests to experimentally confirm self-tuning operation. The results showed simultaneous realization of good ride and compliance with the target speed.