Distance and Angle Formation Scheme for Collision Avoidance of Differential-drive Mobile Robots

This paper proposes combining displacement-based and distance-based approaches to design a strategy for regulation control with collision avoidance for two differential-drive mobile robots. For the attractive control law, the displacement-based method is used. By employing a coordinates change, the front point of the robot is considered to avoid singularities in the control strategy. For the repulsive control law, the displacement-based technique is considered. In this sense, the distance and angle formation dynamics between robots are determined by applying the same coordinates change. Based on those mentioned above, the control strategy consists of two parts: the former, with negative feedback, which is capable to drive the robots to their desired position, while the latter, with positive feedback, which allows to create an unstable focus that produces a counterclockwise angular movement and makes that the robots move away from each other, avoiding collisions between them. Experimental results show the effectiveness of the proposed control law.