A new hybrid macro- and micro-range fast tool servo

A new hybrid macro-and micro-range fast tool servo (FTS) system is developed that enables diamond turning of optical free-form surfaces. The macro-range FTS is driven by a voice coil motor (VCM), and a PZT actuator is used to drive the micro-range FTS, both of which are guided by flexure hinge. The output force of the VCM is enlarged by a lever. A high resolution laser sensor is utilized to measure the displacement of the FTS. The static mechanical performance of flexure hinge has been analyzed. Experimental tests have been carried out to verify the performance of the FTS. The resolution of the macro-range FTS is 34nm with bandwidth up to 16Hz, and the resolution of the micro-displacement FTS can reach to 15nm and the bandwidth reaches 200Hz.