Research On An Intelligent Vehicle System With Automatic Road Identification And Control

The research of intelligent vehicle concerns the motor with its control, and the measurement and computer control, computer vision, sensors, data fusion, vehicle engineering and other areas. This thesis describes the research plan of intelligent vehicle system and the innovation in the system realization that is prepared for the Fourth Competition of National Smart Car.This thesis introduces the design conception and improvements both from the hardware and software. Under the guiding idea of modular design, the overall system is decomposed into path information collecting module, speed acquisition module, motor driving modules and servo driving modules, as well as debug module. Also, the system debugging methods and strategies are introducedThis Smart car in the past on the basis of the bold innovative design and successfully solved the problem of long-sensor Anti-jamming, detection distance and accuracy to detect problems. The designed car has so good detection performance that the forward looking distance reaches above 50cm and the accuracy is 1mm (horizontal black line road detection distance). In addition, a modulated signal is used to control infrared light emission, and thus improves the sensor's anti-interference ability. Under the sun, the smart car works properly. Motor driving circuit uses logic or gate to prevent the motor receiving both the direct and reverse rotating commands instantaneously.The intelligent car uses MC9S12DG128B as the core of entire system processing information and sending control commands, which acquires the infrared sensor information and extracts the center of the black lines and black lines departed from the car to achieve the degree of distinction between the shape of the road, and further processes the information in order to control the steering gear. The system obtains the real-time speed information through using speed sensor, and uses the incremental digital PID control algorithm to achieve the speed of the closed-loop feedback control.It's software of the Intelligent car breaks through the uniform control which has been the bottleneck of performance improvement. To make uniform the incremental PID control algorithm has a high response speed, lower static error and overshoot, and on this basis it is added to the fitting direction and speed to solve the car to run on the runway the distribution of the best speed, best rate of completion of the task of effective control. In the direction of the speed control, it proposed "multi-mode" control concept, which were designed for responding to different situations during the driving. The Intelligent car has the ability to implement appropriate control strategies for different shapes of the road.And it can fast and stable track to complete the whole journey. With advances in sensor program, the intelligent vehicle's directional control algorithm has been implemented all curved on a small S bend, and has successfully solved the oscillation easily arise when the car into the corner and out of the corners.According to global considerations, the mechanical structure of the Intelligent car is optimized. The adjustment of hardware coupled with software optimization, the car's performance has been greatly improved. Tests show that the Intelligent car has a different shape of the road for the implementation of the capacity of the corresponding control strategy can be fast and stable track to complete the entire journey.