Time-optimal dynamic path inversion for an automatic guided vehicle

The article presents the time-optimal trajectory planning of an automatic guided vehicle (AGV) on a given feasible path while respecting velocity, acceleration and jerk constraints. A theoretical result shows the connection for the AGV between the geometric continuity of its paths and the smoothness of its control inputs (linear velocity and steering angle of the AGV motor wheel). The solution hence proposed for the optimal planning is based on a dynamic path inversion algorithm for which first the optimal velocity profile is determined and then the optimal steering signal is derived from a geometrical construction. A set of sufficient conditions for the feasibility of the velocity planning is devised and the practical computation of the optimal velocity profile uses time-discretization and linear programming. A worked example using η³-splines illustrates the method.