A curved-beam based quasi-constant force mechanism supporting large range and force-sensitive robotic manipulation

Emerging applications of force-sensitive manipulation with the requirements on grasping safety and efficiency pose significant challenges on the design of compliant constant-force mechanisms with large operating ranges. In this paper, we propose a novel curved-beam based quasi-constant force mechanism fully compatible with the additive manufacturing technology, which is configurable with appropriate arc-elements to achieve quasi-constant force output with a large motion stroke. We develop an analytical model to describe the static deformation behavior of the proposed mechanism and analyze the performance sensitivity of its structural parameters, with which we also propose the optimization formulation and general guidelines for the design of curved-beam based compliant quasi-constant force mechanisms to meet force and displacement requirements. Finite element analysis and experiments are also conducted to comprehensively evaluate the proposed design, demonstrating significant performance improvement over existing results.