Optimum Design of a Complex Planar Mechanism

Abstract

Presented is the optimal design of a planar mechanism whose configuration is generally more complex than those investigated in previous research. Specifically the paper deals with the synthesis of a linkage consisting of three connected four-bar chains used to open and close a convertible top of an automobile. The design objective and several of the constraints are of a type not previously considered in mechanism optimization problems. The formulation of the design problem is accomplished in such a way that an equality constraint, which would normally exist, is eliminated, resulting in a problem that is much easier to solve. The SUMT-Version 4 program is applied to the optimization, with a graphic computer terminal used to obtain an initial trial design. The optimal design is compared with a mechanism actually used in an automobile convertible top.