Line-of-Sight Path-Following for Input-Constrained Differential Drive Mobile Robots

In this paper, we propose line-of-sight path-following schemes for input-constrained differential drive mobile robots moving along paths composed of straight line segments. Limits on wheel velocities induce a constraint that couples speed and yaw rate. The robot is to adapt its speed to follow the path with minimal path deviations and overshoot. We propose two schemes that appropriately attenuate speed in favor of yaw rate by considering curvature. The cascade of the guidance law and heading controller is shown to be uniformly semiglobally exponentially stable (USGES). Simulations validate the proposed approach, showing improved results compared to a constant speed baseline.