Research On Large Feeding Force And Nanoprecision Drive Parts Based On Thermal Deformation

In order to realize nano feeding under large feeding force, according to the research existing state of nano feeding device all over the world and development tendency of this technic in developed country, combing with china 863 Program "the key technic research of nano precision drive parts having large feeding force", a nano precision feeding scheme based on thermal deformation is presented, the mathematic modal of nano drive parts based on metal thermal deformation is established and stepped exponential fitting method is first presented which can determine the parameters of modal. Research on coefficient of heat conductivity, caloric receptivity, thermal displacement of nano drive parts is developed, the effects for the temperature field and displacement field caused by different control method, different experimental condition are analyzed, the controllability and control precision on thermal displacement are principally researched. Considering the controlled device have the characteristics of nonlinear, time-lag and the variation modal parameters, the multimodal control idea based on forecast is presented here, so the optimal two-stage feeding value is obtained. Thus this scheme not only have the nano feeding, but also break through the conventional method on thermal deformation—passive compensation. Including:Chapter 1, precision processing and state-of-the-art and its importance of micro feeding are represented, combing with the research existing state of nano feeding device all over the world and development tendency of this technic in developed country, research content is presented in this chapter, meanwhile, each chapter of this dissertation is arranged.Chapter 2, according to thermal deformation drive method, the feasibility of this method is analyzed, the effects to response characteristic that caused by variation of the key parameters are simulated by Matlab, the general system constitution and the design of hardware are introduced.Chapter 3, mathematic modal of drive parts is established by simplifying partial differential equation based on thermal conduction, considering the controlled device have the characteristics of nonlinear, time-lag and the variation modal parameters, so the variation ranges of modal are determined through stepped exponential fitting method and a large numbers of experimental findings, the time-lag of system is researched. The multimodal control idea based on forecast is presented here and two-stage drive scheme is presented in order to solve the contradiction of response speed and control precision, in the first feeding stage, slide mode and alterable structure control strategy is adopted to insure the quickly response speed; the second feeding stage needs nano feeding precision, so the second generation slide mode and alterable structurecontrol strategy that is first presented is used, 10nm feeding precision is obtained.Chapter 4, the major functions of control system are analyzed and designed in this chapter, the data communication scheme and communication protocol between WS16DP-6 computer and upper machine are introduced. At last, the development course of software for upper machine and lower machine is introduced, the main interfaces are described, the system operates very well through testing operation and reach to the design demand.Chapter 5, a large numbers of experimental findings is shown, the variation characteristic of system mathematic modal obtained in graph tables is analyzed, precision analyse is developed. The last, corresponding experiments according to different material are done.Last chapter, the full paper is generalized roundly and the next research work is prospected.