Implementation of Follow the Gap Method for Holonomic Mobile Robot Obstacle Avoidance

An obstacle avoidance is the ability to avoid obstacles by finding a safe path from initial to target position. The robots utilize sensors such as LiDAR, cameras and infrared to provide obstacles data to be processed by obstacle avoidance methods. This study proposes to implement the Follow the Gap Method (FGM) on a mecanum-wheeled holonomic robot with a Sharp GP2Y0A21YK0F IR sensor to improve omnidirectional maneuverability. The sensor is moved by a servo motor from 15° to 160° so that it has a Field of View (FoV) of 145°. It measures a distance of 60 to 70 cm between the robot and the obstacle with a reading interval of 20 ms resulting in an average accuracy of 98.01%. FGM observes the maximum gap in front of the robot and then determine the angle of the midpoint or center of the maximum gap. The robot passes through the center position of the maximum gap to avoid collision with obstacles. Based on the experimental results, the proposed method successfully determines the maximum gap center angle accurately so that the robot can avoid obstacles. The movement of the robot deviated from reference path with a difference of one to five cm.