Collision-Avoidance Control for Human Side-Following Navigation of an Autonomous Mobile Robot

In this article, we propose a novel collision-avoidance control design for human side-following of a mobile robot. This design allows a mobile robot to choose a suitable side-following position according to the acquired point cloud data, and control the robot to move toward the best-possible following position while avoiding obstacles. The idea is to keep the user and robot not to lose the sight of each other. Based on this concept, the robot chooses the best position in the visibility field for continuous following while avoiding obstacles. The visibility field is built based on the extended ray-casting algorithm. Combining the extended ray-casting with the mapping of the moving grid, the field of view of the user and the robot can be aligned. The proposed intelligent visibility algorithm(ISA) allows the robot to find the best possible following position at each time instant. This method enables the robot to use a single 2D LiDAR to detect the user and obstacles for real-time side following without colliding with any obstacles. The experimental results on a self-made laboratory mobile robot verified the proposed method. It is demonstrated that the robot can follow the user side-by-side in indoor environments with the capacity to continue side-following after avoiding static and dynamic obstacles.