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Fast Tool Servo（FTS）systems in ultra-precision diamond turning is a promising and competent technology for fabricating optical freeform surfaces or micro-structured surfaces with sub-micrometric accuracy and nanometric surface finish.Currently,there are many kinds of FTS systems which are developed using different driving principles.These previously developed FTS systems were mainly focused on small stroke range with high frequency or large stroke range with low-frequency,which would not completely fulfill the potential manufacturing applications requiring large stroke with high frequency.Therefore,this thesis is devoted to blance the conflicts between stroke and frequency by developing a novel trans-scale FTS system.This newly developed trans-scale FTS system adopts serially combined hybrid actuations in the meso-and micro-range which enables diamond turning to generate optical freeform surfaces with high sag value and high spatial density.With the compact design of the trans-scale FTS system,a dual-stage flexure mechanism is designed together with the armature（mover）of a home-designed voice coil motor（VCM）.In the dual-stage flexure mechanism,the stage-1 in the meso-range is driven by the VCM and guided by a cross-shaped double parallelogram mechanism which results in producing a large stroke with relatively low frequency.Meanwhile,a piezoelectric actuator（PEA）is used to drive stage-2 working in the micro-range which is also guided by a double parallelogram mechanism using eight leaf-spring flexure hinges.Taking advantage of the PEA,high frequency with relatively small stroke is obtained.A three dimensional（3-D）structure model of the VCM actuated FTS as well as the transscale FTS system is constructed.With assistance of the finite element analysis and analytical modeling,the structural parameters of the VCM actuated FTS system is deliberately selected to make a balance between the travel and natural frequency,through fully considering the static,dynamic,and electromagnetic performances.Furthermore,the PEA is embedded to construct the trans-scale FTS system,and the parameters of the PEA based stage is further determined to achieve high lateral stiffness,high resonant frequency and sufficient stroke.Finally,both the prototype of the VCM actuated FTS and the trans-scale FTS system are fabricated and experimentally demonstrated.The VCM actuated FTS is tested to have a stroke of ±59.02 μm and first natural frequency of 253 Hz.By constructing a closed-loop control using PID controller with the internal-model based resonant controller,the error for tracking a100 Hz harmonic trajectory with ±10 μm amplitude is demonstrated to be only 0.144 μm,which is sufficiently small considering the relatively high frequency.With respect to the trans-scale FTS system,it is experimentally demonstrated to achieve a stroke of ±55.70 μm,and bandwidth of 269 Hz for the stage-1.Meanwhile,the stage-2 can achieve a stroke of 9.75 μm with resonant frequency of 7362 Hz.In the future,the control algorithm as well as the practical tracking testing will be presented.