Topology optimization of multiple inputs and multiple outputs compliant mechanisms using the ground structure approach

A new topology optimization method of compliant mechanisms with multiple inputs and multiple outputs using the ground structure approach is presented. Frame elements are chosen to represent the design domain because they are capable of capturing the bending modes. The multi-objective is developed by the strain energy and the mutual potential energy to design a mechanism, which meets both stiffness and flexibility requirements, respectively. The suppression strategy of input and output coupling terms is studied, and the expression of output coupling terms is further developed. The sensitivities of the objective functions are computed by the adjoint method, and the method of moving asymptotes (MMA) is employed as optimizer. The numerical example is presented to show the feasibility of the present method.