Trajectory Tracking Using Sliding Mode Control with Obstacle Avoidance for a Ground Robot

This paper presents a sliding mode control based strategy for tracking a desired trajectory in the presence of static obstacles for a ground robot. The conventional sliding mode control is employed with a saturation function to reduce the chattering issues. Additionally, an approach based on control barrier functions is implemented for obstacle avoidance, utilizing a second-order barrier function. For collision avoidance, the robot is modeled by a double integrator model to optimize the control inputs, which are then mapped on a unicycle kinematic model using an approximation. The results of numerical simulations validate the performance of the proposed approach in the presence of disturbance for a desired trajectory. Experimental validation is also provided to establish the efficacy of the proposed strategy using a fourwheeled differential drive robot and a camera-based localization system, both of which are developed in-house.