Dynamic And Static Stiffness Analysis Of Force Feedback Multi-dimensional Controller

The application of multi dimensional force feedback controller is more and more widely in high-tech area.The force feedback controller is applied in the corresponding field,force feedback manipulator must be deformed under external force.The size and direction of it’s deformation and pose,it hinges on external force and the stiffness of mechanism.The specific research results and innovation points are as follows:(1)It is difficult to solve positive solution for parallel mechanism.The paper obtained the positive solutions of 3-URS parallel mechanism with the method of setting redundant sensors,and according to the structural characteristics of 3-URS parallel mechanism.Motion space of the mechanism is obtained by the positive solution.The inverse kinematics equation is established by geometric relation and positive solution.The Jacobian matrix of mechanism is obtained by the method of first order influence coefficient.It provided a theoretical basis for the control the mechanism.(2)The error model of each branch chain is established by used matrix differential theory.The pose error model of the moving platform is obtained by integrated error of 3 branch chain.It provides a theoretical basis for the calibration of the prototype of the mechanism,kinematics compensation,and the avoidance of the larger errors in the actual operation.(3)In order to solve the problem that the stiffness matrix of the irregular component is difficult,the paper presents a new method based on multiple linear regression theory.By used multiple linear regression method to calculate the element values of stiffness matrix,and used F test,t test,goodness of fit test,got the U type pair exact stiffness matrix.The value of analysis and the value of ANSYS workbench were compared.(4)The conversion relation between the stiffness matrix and the transfer matrix of the spatial member is derived.The transformation matrix is derived in different coordinate system.The method is used to calculate the stiffness matrix of the spatial member with multiple units.The unit stiffness matrix of the upper and lower connect rods is obtained by the transfer matrix method.(5)The static stiffness of the parallel mechanism with complex components is difficult.In order to solve it,a semi analytical method is proposed.The stiffness matrix of each branch is superposed by the transfer of all kinematic pair.The stiffness matrix of the whole machine is obtained based on the force balance and displacement balance equation.The law of the six principal stiffness directions variation with the length of upper and lower was given.(6)Modal analysis,harmonic response analysis and transient dynamic analysis are carried out by used ANSYS workbench software,and obtained the six order natural frequency and vibration mode of the mechanism.The dynamic stiffness characteristics of the mechanism in a certain frequency range are presented.The curve of dynamic stiffness with time was obtained.