Abstract
Following a contour disposed on the ground is an important problem in autonomous vehicles navigation. It serves for autonomous-guided vehicles in flexible manufactoring cells to follow a cable mounted on the floor and for autonomous cars to keep the road using the demarcation lines. The paper presents some solutions designed by the authors for mobile robots, using one to three light sensors or CCD cameras. Cameras can be mounted on the robots and guided by servomotors to track or monitor color, or can be mounted outside the robot and supported by powerfull image processing software. as well as, to identify the proper trajectory and communicate, via a wireless interface, the movements corrections to the robot. Three configurations of the robots used are described: two LEGO wheeled robots build up with RCX and NXT LEGO boxes, which include adequte sensor and actuator units and another wheeled robot named IZEBOT. Experiments carried out for line tracking with maxim speeds allowed to keep the race are briefly presented, as well as routines which implement the algorithms in high-level (PBASIC for IZEBOT) and graphic programming environments (for the two LEGO robots) are also briefly presented.
Keywords: Robots, Line tracking, Sensors, Algorithms