Parametric Continuous Curvature Path for Smooth Steering with Car-like Vehicles

This paper proposes a solution to obtain parametric continuous curvature path for nonholonomic car-like vehicle and addresses also efficient algorithm to obtain an appropriate reference path for smooth path following. As a local planner using parametrically adjustable clothoid, the proposed solution, of constant sharpness, permits to obtain continuous curvature and thus smooth steering behavior of the vehicle which enhances the passenger comfort. The proposed parametric continuous curvature path is integrated in a global planner which includes an appropriate way of isolating the boundary conditions of each local planner. This last characteristic is useful to reconstruct a smooth reference path from raw data of actual vehicle trajectory. The solution is applied to a real road datasets and tested using shape Lyapunov based controller for validating the effectiveness on path following performance. The simulated results show reliable and enhanced performance for vehicle path following when the proposed algorithms are used.