Research Of Stop And Go Cruise Control Technology Based On Laser Radar

Stop & Go cruise control system aiming at the city complicated traffic situation can automatically start and stop vehicle according to the preceding vehicle's movement,reduce the intensity of the driving operation and improve vehicle safety. Object tracking and recognition are the preconditions for stop & go cruise system. So, in this paper, we researched on object tracking and recognition method based on laser radar and stop & go cruise controller.Firstly, this paper briefly introduced the overall structure of TORCS and CyberC3 smart car research platform, detailedly analysed the causes of laser radar tolerance and the effect of laser radar installation location on object tracking and recognition method.Then, this paper researched on object tracking and recognition method based on laser radar. The bright spots of this method are as follows: Cluster fusion algorithm according to the shape and contour characteristics of vehicle is presented to solve the problem of one object separated into multiple parts due to occlusions or bad reflectivity; geometric center is used as tracking center of Kalman filter, and a method of coordinate transformation is utilized to eliminate the impact of shape change on tracking center and improve tracking precision; vehicle's rectangle projection along with velocity feature is introduced to recognize vehicle. Experiments shows, this method has the advantage of high precision, fast processing and strong robustness, and in the AMD3200+ desktop computer the average processing time for each frame is about 12 ms.Finally, this paper designed a two-layers stop & go cruise controller. The upper controller is completely out of the vehicle model, based on established goal performance function, according to inter-vehicular space deviation and velocity deviation, and used linear quadratic optimal (LQ) control algorithm to calculate the expected acceleration. The lower controller is a classic PID controller. This controller controls the throttle or brakes to achieve the desired acceleration. A variety of driving conditions experiments show, this controller can reasonably control vehicle's starting, accelerating and parking, and finally met design requirements.