Design And Optimization Of Precise Micro-loading And Clamping Mechanism

As the researches of micro-electro-mechanical systems(MEMS)are continuously getting deeper and wider,the mechanical properties of MEMS micro components come into scholars’ notice.There is a growing number of domestic and abroad researchers studying this topic.Due to the scale effect,there may be huge differences between the mechanical properties of microscale or nanoscale materials and that of macroscale materials,which shows a great influence on the overall design and performance of MEMS.The traditional material testing instrument can hardly meet the requirements of micro component testing.A set of micro component testing device based on tensile method is designed.The design method of flexible hinge transmission mechanism,precise microloading device and clamping mechanism is emphatically researched.A feasible method for mechanical properties testing of micro components is provided.A micro components mechanical properties testing system based on tensile method is designed in this thesis.The system includes mechanical devices and data acquisition and control systems.The design of mechanical devices is mainly researched.The primary work is summarized as follows:1.The design method of flexible hinge transmission mechanism is studied from two perspectives: the analysis of the stiffness of flexible hinges and the displacement amplification ratio of mechanism.The design schemes of loading mechanism and clamping mechanism that satisfy the design requirements are given by orthogonal test method.The precise micro-loading is realized with the piezoelectric ceramic driver.The design schemes are validated by simulation.2.The machining process design of micro component specimens and flexure hinge transmission mechanisms,the design of auxiliary alignment device and selection of experimental equipments are completed.The whole micro component testing device is built and the tensile testing is carried out.Aiming at the problems existing in test device and processing level which lead to the failure to meet the test requirements,the corresponding improvement schemes are put forward.3.The factors affecting the performance of flexible hinge transmission mechanism are analyzed from the view of energy storage.The optimal design of loading mechanism is accomplished by single factor method.In view of the problem that clamping mechanism may cause stress concentration or even fracture of the specimen,the optimal design scheme of the clamping mechanism is given.4.The checking calculation,simulation experiment and mechanical efficiency calculation of the optimized structures are carried out.It is verified that the optimized loading mechanism can effectively reduce the processing difficulty and improve the output characteristics of the testing mechanism.