A Rapid Design Method of Anti-deformation Fixture Layout for Thin-Walled Structures

Minimizing workpiece deformation is significant to maintain accuracy in the machining and assembly processes of metal thin-walled parts, which can be achieved by anti-deformation fixture layout design. The state-of-the-art methods of fixture layout are almost based on iterative finite element analysis (FEA), which involve high time cost. A rapid design method of fixture layout based on hybrid particle swarm optimization (HPSO) algorithm is proposed in this paper to locate thin-walled structures efficiently. On the basis of elastic plate theory, the deformations of workpieces under gravity or concentrated forces are described by expressions. Flexible tooling system is applied in positioning process and constraints between fixture elements and workpieces are obtained according to design demands. Average deformation of all measurement nodes on the metal structure along normal direction is set as objective function. Then, an optimal fixture layout scheme is designed to minimize overall deformation of thin-walled workpiece based on hybrid particle swarm optimization algorithm. Finally, the proposed method is applied to fixture layout design of thin-walled structure with simply supported edges. Compared with results of current methods, time cost of the proposed method is obviously less while keeping accuracy.