Study On Bionic Thermostable Structure And Its Control In Precision Machine

The research theme of this dissertation is the working mechanism of bionic thermostable component. Combined with the Project of National Natural Science Foundation?Study on Bionic Thermal Robust Component for Precision Machine Tools" (No.59805018), actively absorbed the original thoughts and new technologies of correlative subjects, piezoelectric bionic intelligent structure and its applications on the engineering realm are systematically and thoroughly studied and many innovative and unique views are put forward so as to improve the control performance of piezoelectric intelligent structure. And it was introduced into the control realm of the thermal deformation of precision machine. The characteristics of piezoelectric material, the design method of bionic thermostable structure and theirs applications are systematically and profoundly studied on both theory and fundamental technique.The main contributions of this dissertation are briefly presented as follows:1. The theory and basic equations of piezothermoelectric elastic medium were established by analyzing the function mechanism of piezothermoelectric coupling field. From the view of the basic principles of mechanics, electricity and thermodynamics, the basic coupling equations of piezothermoelectric elastic medium were concluded. Proceeding from the constitutive equations of piezothermoelectric elastic medium, the constitutive equations and control equations of non-linear piezothermoelectricity were developed and the interactional coupling dynamics model of mechanics-thermal-electric field in the piezoelectric intelligent control system was established.2. The internal relations between the characteristics of intelligent piezoelectric material and its components, manufacturing technologies were researched. Analyzing the working mechanism of piezoelectric material, the main piezoelectric characteristics of typical piezoelectric material were analyzed and studied. Based on these analyses, the manufacturing technology was discussed. According to the characteristic of PbZrCVPbTiOs solid solution's phase-chart, the relations between piezoelectric characteristics of piezoelectric material and its components were analyzed. The relations between piezoelectric characteristic such as piezoelectric constant, electromechanical coupling coefficient, mechanical quality factor, etc. and its components, granular diameter and manufacturing technology were studied. The new kind of piezoelectric materials桺ZT-5 used in the bionic thermostable structure was developed and its piezoelectric characteristics were analyzed.3. Based on the working characteristics of piezoelectric transducer in the bionic thermostable structure, mathematics models of various piezoelectric transducers were brought forward and theory models of piezoelectric transducer were established The influences of the important factors of piezoelectric actuator on the conversion efficiency of piezoelectric transducer were analyzed. And the simulation calculation of its model was carried out and so the validity of this model was proved.4. The working mechanism of piezoelectric active member in the bionic thermostable structure was probed into. Based on the piezoelectric actuating effect of piezoelectric material, the design theory, parameter selection and its effect on the performance of piezoelectric active member were* The project is supported by the National Natural Science Foundation of China (No: 59805018)discussed. A new type piezoelectric active member adopted in the thermo-modality control of intelligent structure was designed and manufactured. And the relations between its working properties, output displacement, output force, etc. and various influence factors were studied through experiments.5. The modal control and the optimal placement of piezoelectric sensor in bionic thermostable structure were explored. The quasi-static equations of piezothermoelectricity were used to deduce the finite element dynamic coupling model of piezotherm...