Optimization Design of Electromagnetic Actuator Applied as Fast Tool Servo

Abstract

Fast tool servos (FTS) for single point diamond turning are widely employed for machine optical free-form surfaces. A FTS with a large stroke and a high bandwidth can increase the efficiency of a machine and complexity of a work-piece. In this paper, a FTS driven by a Maxwell electromagnetic actuator is developed to obtain a relatively large stroke and high bandwidth. In this study, a multi-objective optimization model is proposed based on the whole system by considering electromagnetic driving principles, kinematic model, and mechanical model. The proposed optimization model can be applied to solve the parameters of electromagnetic actuators with diverse application requirements. A sequential quadratic programming (SQP) algorithm is implemented to solve the problem. The optimization results are verified through both finite element analysis and experiments. The optimized FTS can produce 49.55 μm of full stroke with a frequency response of 3.2 kHz.

Keywords

• electromagnetic actuator
• fast tool servo
• freeform optics
• sequential quadratic programming