| With the development of technology,ultra-precision diamond cutting has been a high repeatable and high precision surface finish process technology for various materials.Therefore,ultra-precision diamond cutting technology is widely used in the precision parts manufacturing of many areas.From the perspective of swing feed ultra-precision diamond turning of metal-aluminum mirror,this thesis describes the design principle,system errors and performance of fast tool servo system,constructs the kinematic error model of machine tool to obtain the main errors aff ecting processing precision,then proposes relative error compensation method to provide the theoretical basis for improving manufacturing precision.Firstly,this thesis depicts the movement principle and process method based on the presentation of R-? construction machine tool.The processing range of swing feed ultra-precision diamond turning machine is confirmed referring to the real configuration of machine tool,then the calculation model of adjustment parameters for taget sphere surface is constructed.Through three-point-method to confirm the best fit sphere of paraboloid,on this basis,the calculation method of three-dimensional aspherity of paraboloid relative to its best fit sphere,processing method and the motion regularity of fast tool servo system during cutting are obtained.Subsequently,the manufacturing methods of asphere surface with T-type ultra-precision turning machine and swing feed ultra-precision turning machine are compared.At the end,by analyzing the regulation of cutting parameters during oblique cutting,the performance indicators of fast tool servo system are obtained.Secondly,a fast tool servo system is developed.By mechanics modeling and finite elements analysis method to analyse the whole system and single hinge,the construction of FTS system based on a piezoelectric ceramics actuator dri ving hinges is designed.The relationships between the performance parameters and system parameters of FTS are confirmed with dynamics analysis.Key performance parameters of the FTS including parasite error,static stiffness,cutting stiffness,inherent frequence,repeat position precision,resolution,max worke range,are tested.Previous works provide a fundamental for error compensation with FTS system.Thirdly,spatial geometric error model is constructed by multi-body system kinematics theory and the real configuration of machine tool.Based on probability and statistics theory,orthogonal test and the motion precision of machine tool,the regression analysis model and the error sensitivity analysis model of swing feed ultra-precision turning machine tool are obtained,then the main erro rs affecting the processing precision are identified.The regulation and range of main errors relative to spatial error are known.Finally,the error compensation method of swing feed ultra-precision diamond turning machine tool is research.On the advantage of easy adjustment of machine tool,a static error compensation is used to calibrate the position of main elemens of machine tool in order to reduce the system error based on the cutting of flat surface in 200 mm diameter.In this way,the PV value of flat surface in 180 mm range is decerased from 0.5?m to 0.24?m after the static error compensation.During processing,in-site error compensation method with 4D dynamic interferometer to measure the surface of part is used to reduce the form error of parts.By a series cutting experiment of three parts including a sphere surface in 100 mm diameter,and a parabolid surface in 500 mm diameter,the PV values of sphere surface and asphere surface are decerased from 8.89?m to 0.45?m,and 2.7?m to 1.45?m after in-site error compensation,respectively. |
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