Research Of Path Planning And Moving Control In Outdoor Mobile Robot

Outdoor intelligent mobile robot is an important member of the family of robots, which detects outer environment information through perception technologies such as machine vision, laser radar, magnetic sensor, digital maps, and GPS, etc.,monitor systems then analyze and fuse the data and obtain the control information, and use them in vehicle navigation. Navigation control and local planning are key techniques of mobile robot. This thesis research and discuss some key techniques of navigation control and obstacle avoidance based on the mobile robot platform, which is developed by Shijiazhuang Railway Institute and State Key Laboratory of Intelligent Technology and System of Tsinghua University.Control of steering wheel,gun and brake is the base of vehicle state of motion, which play an important part in the whole control system.The thesis firstly introduces the architecture of the intelligible vehicle, and then introduces the power system, steering wheel control system, speed control system and brake control system.Local path planning is the key of the navigation control system.In this part, some early algorithms are reviewed firstly, including AFM, PFM, VFF, VFH, etc. The thesis analyses and compares these the theories and characters of these algorithms, and then apply VPH in obstacle avoidance of mobile vehicle. After practical test, the effect is satisfying, and the expectant target is attained.Path tracking consists of straight line path tracking and curve line path tracking. The thesis firstly analyses the performance of path tracking, and then discusses the method of multiple target path tracking and a new conception of node boundary is presented to improve the methods.For the shortage of simple PID, declination-case-control algorithm is proposed.In detail, in the case of large declination, constant angle approaching algorithm is selected; in the case of normal declination, PID control algorithm is selected; and in the case of tiny declination, fuzzy control algorithm is applied. Curve line path tracking algorythm is introduced based on straight line path tracking algorithm. Remote control system is one of the important part of intelligent mobile robot. The thesis firstly introduces the overall architecture of remote control system, and then introduces the environment information collection system of vehicle, command control system and wireless communication system.At the end of the thesis, some conclusion and future work are achieved.