A new approach for line following robot using radius of path curvature and differential drive kinematics

This paper presents a new idea about the development of line following algorithm for a differential drive mobile robot. The paper describes in detail this idea using Geometry to determine the radius of path curvature and based on it the desired difference between angular velocity of two wheels is calculated using Differential drive Kinematics. This robot uses an array of IR reflective sensors to find out the degree to which a circular arc deviates from a straight line. In this scheme a single PID controller is used to control the desired angular velocity for both wheels. To maintain the circular path of desired radius with constant linear velocity, the output of same PID controller is added in left wheel actuator and subtracted from right wheel actuator. Therefore the desired Radius of circular arc is followed by robot.