Design of a Novel Large-Stroke Compliant Constant-Torque Mechanism Based on Chained Beam-Constraint Model

This study addressed the development of a novel compliant constant-torque mechanism (CCTM) that utilizes Bezier curved beams to provide a large stroke in the constant-torque operating range. Previous CCTMs are limited by their working stroke, which reduces their applicability. The proposed mechanism is based on an analytical model using the chained beam-constraint model (CBCM), which captures the kinetostatic behavior of flexible segments. A genetic algorithm based on the CBCM was used to obtain the optimal structure, which was then verified through finite element analysis and experimental results. The results show that the proposed CCTM provides good flatness with a deviation of 3.7% and a large stroke of 80 deg in the constant-torque working range, while maintaining compactness. This novel CCTM has the potential to provide a simple and effective solution for torque regulators in various applications.