Trajectory Planning, Optimization and Control of a Hybrid Mechanical Press

Hybrid mechanical press is an innovative sheet metal stamping press that has the advantages of both mechanical press and the hydraulic press. This paper focuses on the control of the hybrid mechanical press, including trajectory planning, trajectory optimization and real time feedback control. The trajectory planning is based on inverse kinematics and cubic spline interpolation. The trajectory optimization is used to realize the desirable punch trajectory under multiple constraints on velocity, acceleration and jerk of the servomotor. Finally, an improved PID algorithm, called the integral separated piecewise PID scheme, is used for real time feedback control. Based on the experiments on a 25 ton industrial prototype, the control ensures the desirable performance of the press. Key-Words: Hybrid Machines, Mechanical Press, Trajectory Planning, Trajectory Optimization, PID Control