Theoretical And Experimental Research On Multi-dimensional Force Sensing Mechanism Of Special Configuration

In this paper,the parallel force sensing mechanism(PFSM)is studied.It’s special configuration of PFSM is analyzed,the stiffness model and force mapping model are established.It’s data acquisition system and prototype are designed.The calibration experiment is completed.These work enrich the configuration of PFSM and provides new ideas for the application of PFSM.Firstly,the configuration of PFSM is designed on the basis of decoupling characteristic,a 8/4-4 decoupling PFSM is presented.Based on the condition number as a index,the isotropic configuration and near singular configuration of the 8/4-4 decoupling PFSM are obtained.The performance is verified by the finite element analysis.Secondly,Based on the pseudo rigid body model method,combining the principle of virtual work,the principle of superposition of deformation and the principle of deformation coordination,the FPSM’s mathematical derivation of the stiffness model is obtained.The stiffness model of the FPSM is established based on the derived theory.It’s stiffness matrix and force mapping matrix are obtained.The simulation verification is carried out.The reason of the error is analyzed.Then,in view of the large deformation of the flexible mechanism,the reconfigurable idea is introduced in the pseudo rigid body model method,considered the effecet of mechanism deformation on stiffness model under the action of external load,a new method of stiffness modeling based on reconfigurable idea is presented,which makes the process of mechanism deforming continuity.The deforming process is simulated by the reconstruction model.The reconfigurable model of the stiffness matrix and the force mapping matrix is obtained.Finally,based on the proposed PFSM,a capacitive six-axis force sensor is designed,it’s capacitive array and the measurement model are constructed.A data acquisition hardware system based on the capacitive array is designed.The whole and part structure of the capacitive sensor are designed.Based on the least squares method,the virtual calibration experiment of the six-axis capacitive sensor is carried out by MATLAB and ANSYS software.