Time-Optimal Trajectory Planning for Robots with Identified Dynamics

In industrial applications, time-optimal trajectory planning (TOTP) is essential for robotic systems, while the exact dynamic models are sometimes unavailable in the planning process. This paper presents an optimization-based method to deal with the TOTP of robotic systems with identified dynamics. First, the dynamic model of the robotic system is identified in a linear format. Then given a planned geometric path, a non-convex optimization problem including jerk and torque constraints is formulated directly from the linear model to calculate the time-optimal trajectory. To get the numerical solution, the optimization is discretized and solved using sequential convex programming (SCP). Real-world experiments are conducted on a 6-DOF industrial robot. The trajectory planning and trajectory tracking results consistently demonstrate the effectiveness of the proposed method.