Intelligent optimization of compliant constant-force mechanism support extending work stroke

Abstract Compliant constant-force mechanisms (CCFM) are known for their ability to deliver a stable force output over a designated range and have been widely utilized in applications such as ultraprecision polishing and micromanipulation. However, the constant-force range achievable by typical CCFM remains limited, restricting their broader application. Meanwhile, system strategies for expanding the constant-force range while maintaining force stability are still lacking.The study proposes an intelligent optimization framework to address this issue, aiming to broaden the constant-force operating range of CCFM.The theoretical model of the positive-negative stiffness mechanism for CCFM is first established, and the constant-force characteristics and initial design parameters are determined. Then, sensitivity analysis is used to identify key design variables, enabling the efficient construction of the optimization objective function. Following this, structural optimization is performed using a genetic algorithm (GA), and the effectiveness of the optimized design is validated through finite element simulations and experimental testing. The results show that the optimized CCFM expands the constant-force region by approximately 30% compared to the initial design. The proposed method offers an effective strategy for enhancing the functionality and application scope of compliant constant-force mechanisms.