Design and Control of a Novel Fast Tool Servo Used in Diamond Turning of Freeform Optics

Abstract:

Optical free-form surfaces are becoming more and more popular in the industry application, which can be fabricated by diamond turning based on fast tool servo (FTS). It is an efficient, precise and low-cost processing method. In order to use diamond turning to fabricate the freeform optics, this paper develops a novel long range fast tool servo which is actuated by voice coil motor. The total range can reach up to 30 mm. The important parts of the FTS have been simulated and analyzed. The transfer function model identification of the FTS has been accomplished. Since the desired tool trajectories are approximately periodic signals in freeform surfaces turning, and the adaptive feedforward cancellation (AFC) control can achieve perfect tracking and disturbance rejection of periodic signals, the AFC control is designed to be added on the IMC-PID controller.

• Periodical: Key Engineering Materials (Volume 679)
• Pages: 73-78
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.679.73
• Online since: February 2016
• Authors: Fu Jing Tian, Zi Qiang Yin, Sheng Yi Li*
• Keywords: Adaptive Feedforward Cancellation (AFC), Diamond Turning, Fast Tool Servo, Free-Form Optics, Voice Coil Motor

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