Research on structural optimization of 3-TPT parallel mechanism based on stiffness characteristics

Aiming at the problem of weak stiffness of parallel mechanism, the structural dimension was optimized according to the main influencing factors under the condition of static equilibrium. The influence of each component on the stiffness of the branched chain was analyzed by solving the stiffness of the branched chain. The stiffness matrix of whole machine was obtained by using analytical model method, which was analyzed and simulated by means of minimum eigenvalue method and static stiffness performance quotient. The optimal mathematical model was established by improving the minimum eigenvalue of limit points on the boundary as the optimization objective, the working space as the constraint condition, and the size of the main structure as the design variable. Then the size optimization of the 3-TPT parallel mechanism was conducted to improve the stiffness in the workspace. The validity of improved stiffness is verified by the minimum eigenvalue method and the static stiffness performance evaluation method. Communicated by Anurag Purwar