Force Analysis of the Overconstrained Mechanisms Based on Equivalent Stiffness Considering Limb Axial Deformation

Abstract Overconstrained mechanism has the advantages of large bearing capacity and high motion reliability, but its force analysis is complex difficult because system contains overconstraints. Considering limb axial deformation, taking typical 2SS+P 7-SS passive overconstrained mechanisms, 2SPS+P 7-SPS active passive-input mechanisms as examples, a new method based on idea equivalent stiffness proposed. The matrix derived by combining balance deformation compatibility equations with consideration elastic deformations. relationship between constraint wrench magnitudes external force, established. displacement equations. Here, actuated wrenches investigated. Combining mechanism, an analytical forces output displacement, explored. Finally, adaptability to discussed, effect distribution revealed. research results provide theoretical reference for design, practical application mechanism.