Minimum-time trajectory of robot manipulator using Harmony Search algorithm

The optimal trajectory planning is an important function in a robot control area. Generally, the operating function of manipulators requires the highest performance such as minimum time, minimum energy, and no damage to the system. This paper proposes a minimum time trajectory planning that is clamped with cubic splines and uses Harmony Search (HS) algorithm for solving the optimization problem. Minimum time is chosen to be the objective function as time is critical for productivities in the industrial. However, kinematics constraints such as velocities, accelerations and jerks limitation are still considered. In this work, the simulation of the 6-DOFs robot manipulator trajectory is employed to determine the minimum time trajectory planning. The best solution from two techniques, the HS and the sequential quadratic programming (SQP), are compared. The results show that the HS method obtains the optimal interval time better than the SQP method and it does not require finding the initial interval time value for the optimization process. This reduces the complication and time consuming of the optimization process.