Optimization of a crossbar parallel machine tool based on workspace and dexterity

摘要

Increasing workspace and improving dexterity are important tasks for the design of parallel machine tools. The workspace of a crossbar parallel machine tool with constraints is obtained by using a 3D search method based on inverse kinematics. The new Jacobian matrix of the machine is also derived by using the natural coordinate method. Dexterity distribution of the machine tool is obtained on the basis of the workspace and the new Jacobian matrix. Influences of the structural parameters on the workspace volume index (WVI) and global dexterity index (GDI) are analyzed. Structural optimization is conducted by treating the WVI and GDI as the global optimization goals. Unlike the initial data, the optimized results increased by 0.43 and 0.34 times.