| The design, manufacture and application of the precision optical components havealways been an important part of advanced science and technology for every country, and itis one of the flags of a national science and technology level. Whatever aerospace, nationaldefense military, nuclear power and other cutting-edge technology development, or ordinaryoffice, the civilian products, precision optical technology plays an important role in it. Thesingle point diamond ultra-precision turning is an important member of optical elementprocessing technologys. Diamond turning processing optical surface can complete theprocessing in one procedure. Without needing for a second clamping and avoiding the errorcaused by changes in processing benchmark, it is easy to realize the morphology ofmachining precision and surface quality which is required in processing.In recent years, the development of the optical element has progressed from the sphereto the aspheric surface, up to non-axisymmetric curved surface, and no analyticalexpressions of freeform surface. Non-axisymmetric optical surface can’t be processed bytraditional diamond turning technology. Therefore a variety of technologies and equipmentswhich are compatible with non-axisymmetric surfaces have been developed. The Fast ToolServo (FTS) is one of the important branches.Fast tool servo, which is mounted on a traditional ultra-precision diamond turning lathe,can achieve much higher frequency reciprocating motion than lathe spindle does. FTSprovide high frequency response motions along X or Z axis of lathe addition to the motionof lathe. The motion of FTS is synchronized with the spindle rotational angle or timedomain. By now, most of FTSs provide only one DOF. It means there is only one axiswihch is added to those original axes of lathe. For improving on FTS performance, a2DOFs FTS (hereinafter referred to as the2DOF-FTS) is designed in this thesis, which canprovide two high frequency motions along X axis and Z axis of lathe simultaneously.The2DOF-FTS designed in this thesis is formed with paralleled mechanism which hastwo symmetrical single DOF FTS connected with each other. This will make the2DOF-FTShas ability to produce a workpiece which demanded longer strike of a single freedom FTSby means of the trajectory planning for the2DOF-FTS; or from another point of view, the 2DOF-FTS can degrade demanded FTS’s strike by means of this kind of trajectory planning,and improve the frequency response bandwidth of actuator. This thesis describes researchon the technology of2DOF-FTS and the procedure of design and the manufacture of a highfrequency actuator. The following contents in this thesis are presented:The technology of FTS motor driven by variable reluctance normal electromagneticforce was researched. And a prototype motor was manufactured. Methods of determiningthe driving principle and parameters was studied, in addition, motor design with similarneeds in the future was guided. Analog power amplifiers of this motor was designed andmanufactured. The parameters selection of the various components of the circuit wasanalyzed and the decoupling methods of coupled inductive loads were researched. Theexperiment result proved that the sampling frequency of the circuit designed in this thesiswas over1MHz and the circuit met the requirement of2DOF-FTS.The paralleled transmission mechanism of2DOF-FTS was designed, analyzed andmanufactured. The movement characteristic and decoupling was analyzed; the multi-rigidbody and flexible multibody dynamic analysis for this mechanism were discussed. Acomparison and analysis of the impacts of flexible deformation on mechanism movementand driving gave the theory basis of simplifying and lightening inertia of the mechanism.Aiming at the character of2DOF-FTS, tool-path planning was implemented.According to movement character of2DOF-FTS and aiming at several kinds of nonaxisymmetric curved surfaces, tool paths were analyzed and designed. The programmingmethod and characteristic of2DOF-FTS-tool were studied; meanwhile, the advantage ofmanufacturing non-axisymmetric curved surfaces brought by this method was discussed.The result shown processing strike is prompted almost240%in the best interest during theprocessing several non-axisymatric optical surfaces by2DOF-FTS.Control method for2DOF-FTS was designed finally. The mechanical structure of2DOF-FTS and automatically controlled mathematics model of driving circuit wereestablished by experimentation. Combining analysis and modeling for controller and sensor,a adaptive fuzzy sliding modal control method for2DOF-FTS was designed. The result ofsimulation shown that there is almost no supershot, precision of tracing is satisfied with thedemand of2DOF-FTS. This method promoted the control performance significantly relativeto the other general control methods. |
PDF Full Text Request