Design And Research Of Rigid-Flex Coupling Micro-positioning Platform With Three Degrees Of Freedom

At present,in the fields of national defense,aerospace,biological engineering,microelectro mechanical system assembly and precision processing and manufacturing,where micro-nano precision is required,micro-nano ultra-precision positioning technology is widely used.The micro-positioning platform driven by piezoelectric ceramics has become the focus of research and attention of scholars at home and abroad due to the advantages of fast response speed,high positioning accuracy,and large magnification.However,because the micro-positioning platform can withstand less force at the output end in practical applications,it is limited in related fields.Therefore,this paper proposes an idea that can have a large bearing capacity and stability while ensuring the positioning accuracy of the platform,to avoid piezoelectric ceramics and flexible mechanisms from being subjected to a large force,which will affect the normal work.The details are as follows:(1)A three-degree-of-freedom rigid-flexible coupling micro-positioning device is designed.The flexible hinge mechanism and self-locking principle are used to achieve the goal of improving the bearing capacity of the micro-positioning platform while ensuring the positioning accuracy of the device.The principle of motion and self-locking was analyzed,and the critical angle and driving force of self-locking between wedges were calculated.The static and dynamic simulation analysis of the driving plate was performed using finite element.(2)Because the above device has a complicated structure and is not easy to process and analyze,a symmetrical rigid-flexible coupling micro-positioning platform is designed.The positioning platform also uses a wedge structure to realize the self-locking effect and is simple in structure and easy to process and analyze.The flexibility matrix method is used to statically model the flexible drive mechanism,and finite element is used to perform static simulation analysis to verify its accuracy.Through dynamic simulation analysis,the first six natural frequencies of the platform are obtained.The device has good dynamic characteristics.(3)Establish a symmetrical rigid-flexible coupling micro-positioning platform test system,and test and analyze the positioning accuracy,input-output characteristics,response speed,and frequency-amplitude of the platform in the three directions of x,y,and z.