A novel feedforward control technique for a flexible dual manipulator

• We propose a novel trajectory generation method for suppressing residual vibrations.
• We address the point-to-point motion task of a flexible dual manipulator.
• The combination of cycloidal and polynomial functions can generate a smooth trajectory.
• Multimode vibration control can be realized by driving the manipulator along an optimal trajectory.

This paper proposes a feedforward control technique for two flexible links attached to one motor to suppress residual vibrations in a point-to-point motion. In the proposed method, we attempt to express the trajectory of the joint angle using a combination of cycloidal and polynomial functions, which enables the easy generation of a smooth motion. The generated trajectory depends on the coefficients of the polynomial function. To minimize the residual vibrations of the two flexible links, the coefficients are tuned using a particle swarm optimization algorithm, which is a type of a metaheuristic algorithm. The optimal trajectory obtained by this approach can suppress residual vibrations; i.e., multimode vibration control can be realized. Simulations and experiments are performed to evaluate the applicability and effectiveness of the proposed method.