Stress-constrained topology optimization for multi-material thermo-hyperelastic compliant mechanisms based on inverse motion

A stress-constrained topology optimization design for the multi-material thermo-hyperelastic compliant mechanism is investigated in this article, using inverse motion analysis. Through the inverse motion analysis approach, precise control over the geometry of the deformed structure is achieved. A topology optimization model is established for the multi-material thermal hyperelastic compliant mechanism, incorporating constraints on volume, cost and stress, while maximizing displacement as the objective function. Filtering is implemented using an improved partial differential equation, and the stress problem is addressed using the epsilon-relaxation method and the p-norm aggregation function. The sensitivity analysis of the displacement objective function and the stress constraint is conducted. Considering the multi-material thermally actuated actuator as an example, the influence of the stress constraint on the topology optimization design is studied. The results indicate that inverse motion analysis allows for effective control of the output end position of the deformed compliant mechanism.