A Research Of Smart Car System Based On Non-linear PID Controller With Feed-forward

The smart car, one kind of mobile robots, is an integrated system which integrates multiple functions such as environment awareness, planning decision and automatic drive. In order to improve the intelligent vehicle's performance in tracking and moving, an smart car system based on Non-linear PID controller with Feed-forward is designed in this paper, which is researched from hardware systems, control strategy, control algorithm on the basis of intelligent vehicle principle.Firstly, on the basis of analyzing the defection of the traditional linear PID controller, studied the trait of a non-linear module, used the function of f(e,α,δ), and quoted a Non-linear controller. Identified in the premise of a andδ, adjusting the size of function follow the e. Furthermore, in order to effectively extract the differential signal from the system, arranged for a reasonable transitional process, the reference of a track-differentiator (TD), thus effective control the smart car. Besides, the smart car system itself is an inertia delayed-time system, simple adoption of a general non-linear PID controller cannot achieve satisfactory results in the time regulation and speed response of the control system. we applied the non-linear PID integrated with the feed-forward control in the smart car system.Secondly, after analyzing the movement theory of smart car systems and principles of gathering the path of information, firstly carry out the transformation and assemble of the mechanical structure, and then the smart car's power system, steering gear, DC motor, the path identifying and speed detection sensors to contrast, selection and installation, lastly designed the circuit and produced the circuit boards. Then, on the basis of analyzing and researching the hardware structure of the system, through the modular software system programming, effective realize the functions of each module.Finally, the smart car hardware system where the algorithm is applied in, is designed based on HCS12 MCU. Where after, the reliability of this system is tested, which proved that the hardware is simple and reliable; control algorithm can imitate the driving behavior of human to control the smart car to track the path accurately and rapidly.