Abstract: The design of stamping motion is one of the key technologies to make the servo press performing stamping operation perfectly. An interpolation method considering constraints of different orders is proposed based on NURBS motion curve that any one or all constraints of position, velocity and acceleration can be defined at desired key points of the stamping motion in order to satisfy both accuracy and flexibility requirements. An algorithm is presented to generate the dwell section of stamping motion curve with given time span quickly. A reasonable solution is given to define the derivative magnitudes in construction of the interpolation equation to avoid stamping motion curve’s distortion. A method to amend proper velocity or acceleration constraint is proposed to improve the performance of stamping motion curve. Following above discussion, a general process of servo stamping motion design is proposed and an interactive stamping motion design software is developed considering constraints from metal forming operation and actuation capability of the servomotors. Finally, the proposed stamping motion design method is demonstrated by a forming case of automobile wing workpiece.

Key words: motion design, servo press;NURBS motion curve;constraints of different orders;constraint of actuation capability;stamping