Investigation in Autonomous Line Follower Robot

Abstract

The line follower robot is a mobile machine that can detect and follow a line drawn on the floor. In this paper, a predefined path is provided and the path is made up of a black line on a white surface with high contrast color. The mobile robot senses the path with two of its infrared sensors that installed under the robot and a third infrared sensor is used for obstacle avoidance. The left sensor controls the right wheel and the right sensor control the left wheel. The sensors detect the path and provide the information to the microprocessor. The microprocessor activates the motors depending on the path which may be straight or curved. The robot is allowed to follow a line of 4m length with varying wheel diameter and Castor position. The times taken for the travel under different arrangement were tabulated. Design of Experiments is used for finding optimal design parameters of the robot for time taken to complete the travel along the predefined path. The parameters considered are Wheel Diameter ‘D’ for three levels (70 mm, 80 mm, 90 mm), Centre to Centre (C-C Distance) between the Caster wheel centre and the Rear wheel centre for three levels (90 mm, 100 mm, 112 mm). Finally empirical model have been formulated by the application of Regression Modeling after evaluation of Test of hypothesis for above mentioned levels and factors for significant effects. The results obtained from the design of experiments are given fed in to the fuzzy logic controller. The results of the two methods were compared and obtained satisfactory results.