Finite element analysis and optimization in fixture design

Fixturing locating point synthesis considers the workpiece and the fixturing elements to be rigid, but however they are elastic and deformable. To ensure sustained quality of manufacture to meet the design tolerances, fixture design must be predictably repeatable. This paper is concerned with minimizing deformation of the workpiece due to machining loads about fixturing support positions, especially in thin castings. Finite element analysis is used in simulating the deformation of the workpiece at selected points. An optimization algorithm is developed to minimize deflections at these selected nodal points by considering the support and tool locations as design variables. The resulting support locations and tool point designs ensure part support, kinematic closure and minimal workpiece deflections during machining.