Research On Planar 3-DOF Micro Positioning Platform Based On The Hybrid Compliant Hinge

In microelectronic assembly,cell operation,optical engineering and other fields,micro positioning platform with micron level stroke and nanometer precision is an important supporting technology.The compliant mechanism has no gap and free assembly,and it can eliminate the return error.It is an important realization form of the micro positioning platform.At the same time,large travel and high precision are the hot and difficult points in the research of compliant micro positioning platform.In this paper,a hybrid compliant hinge,which can balance the contradiction between stroke and accuracy,is put forward.Then a planar 3-DOF micro positioning platform based on hybrid hinge is studied.The main contents are as follows.First,a kind of hybrid compliant hinge with the advantages of both the right circular hinge and the filleted hinge are proposed,and the static analysis and optimal design of the hinge is carried out.The compliance formula of the hybrid hinge is derived based on the carton’s second theorem.The output displacement calculated by the compliance formula is compared with the output displacement of the finite element simulation,and it is found that there is a large error between the two.Therefore,the output displacement of the hybrid hinge in all directions is obtained by the finite element simulation,and the compliance formula of the hybrid hinge is obtained by using the fitting method.The results show that the output displacement obtained by the method of fitting the compliance formula of the hybrid hinge has little error with the output displacement of the simulation.The comparison of hybrid hinge,right circular hinge and filleted hinge show that the rotation displacement of the hybrid hinge is larger than that of the right circular hinge.The hybrid hinge has higher rotation precision than the filleted hinge.The mathematical model of size optimization was established,and the size of the hybrid hinge is optimized by MATLAB,and the optimum size of the novel hinge is obtained.Then,the planar 3-DOF micro positioning platform based on the novel hybrid flexure hinge is analyzed and optimized.The formula for the amplification ratio of lever amplification mechanism is derived.A comparison is made between the amplification mechanism of the right circular hinge and the hybrid hinge magnification mechanism.It is found that the difference between the two amplification units is very small.The flexibility of the hybrid hinge magnification mechanism is larger than that of the right circular magnification mechanism.Based on the rigid body model,the inverse solution and Jacobi of the parallel micro positioning platform are solved.First,the size of the lever amplification mechanism is optimized,and the optimized amplifier has a larger output displacement.Then the moving platform is optimized so that the micro positioning platform can output more displacement.Finally,the distribution of hinge is analyzed,and the micro positioning platform with superior performance is obtained.The workspace of the micro positioning platform are analyzed.Finally,a micro positioning platform based on a novel hybrid flexure hinge is studied experimentally.The output displacement of two kinds of micro positioning platform is measured by a dual frequency laser interferometer.First,the input force and the input displacement of the micro positioning platform are calibrated.Then the positive and inverse kinematics experiments of the micro positioning platform have been carried out.Finally,the experimental verification of the optimization results of the micro positioning platform proves that the flexibility of the optimized hybrid micro positioning platform is larger.Finally,the reasons for the possible error are analyzed.