Reactive Safe Path Following for Differential Drive Mobile Robots Using Control Barrier Functions

This paper addresses the problem of safe Path Following (PF) for differential drive mobile robots. Our solution builds on Control Lyapunov Functions (CLFs) and Control Barrier Functions (CBFs), which guarantee that the robot will avoid obstacles and will converge to the desired path in the absence of obstacles. We propose a novel Control Lyapunov, and Control Barrier Functions for a Differential Drive mobile Robot (DDR). The novelty of the CBF stems from the fact that it produces a first-order CBF, contrary to the typically used barrier functions, and thus significantly simplifies the control. The proposed CFB also provides hyperparameters that allow the designer to control obstacle avoidance behavior. To demonstrate the control algorithm’s efficacy, the proposed method is implemented on a real DDR to follow a predefined path while avoiding a circular obstacle. We report on the experimental results and the effect of some of the parameters on the system performance.