面向踝关节康复的四自由度广义球面并联机构运动学性能

针对现有踝关节康复机器人运动特性与人体踝关节实际运动特性存在明显差异,导致人机相容性不理想的问题,基于高匹配度的U1U2型踝关节运动拟合模型,提出一种适用于踝关节康复且结构紧凑的四自由度广义球面并联机构.基于螺旋理论分析其运动及约束特性,论证其与踝关节运动拟合模型运动的一致性;分别建立机构的位置及姿态运动学模型,证明了...

Kinematic Performance of 4-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

In the previous rehabilitation robot research, the proposed ankle models have distinctions with the human ankle bone structure. It leads to the unsatisfactory human-machine compatibility of ankle rehabilitation robots constructed based on the fitting onto the motion of these models. A compact 4-DOF generalized spherical parallel mechanism is proposed based on the motion fitting models U₁U₂. In order to prove the feasibility of the mechanism, its motion and constraint characteristics are analyzed based on the screw theory, and its motion consistency with the motion fitting model is discussed. The position and orientation kinematics model of the mechanism were established separately, which proved that the kinematics between the position and orientation is completely decoupled. By analyzing its Jacobian matrix and condition number, it is clarified that the mechanism has kinematic fully-isotropic properties in single direction movement, and has excellent dexterity and manipulability in the ankle working space, and no singularity. It is verified by data comparison that the mechanism has good kinematic characteristics and is suitable for ankle rehabilitation.