Department of Mechanical Engineering, Coimbatore Institute of Technology, Coimbatore Tamil Nadu 641014, India.
Department of Civil Engineering, Rathinam Technical Campus, Coimbatore, Tamil Nadu 641021, India.
Acta Bioeng Biomech. 2021;23(3):175-189.
Exoskeleton robots generally have multi-functions and one such function is doing rehabilitation therapy in upper limb and lower limb in stroke-affected patients. A novel hybrid (serial-parallel) robot manipulator was proposed in this paper for rehabilitation of upper limb and its kinematics are studied systematically. This robot manipulator intends to perform wrist flexion, wrist extension, wrist radial deviation, wrist ulnar deviation, elbow flexion, elbow extension, elbow pronation and elbow supination motions. The contemporary mechanical designs especially the kinematic structure of upper limb exoskeleton robots have a unique feature that is, almost all of them use serial manipulators, and few others used parallel manipulators. The kinematic structure of the proposed robot is that of a hybrid manipulator (two parallel manipulators connected in series) which has 4-degrees-of-freedom. It is composed of an upper 3SPS-type parallel manipulator and 2SPR-type parallel manipulator connected in series.
The Jacobian and Hessian Matrix method was used to derive the manipulator kinematic formula for solving the displacement, velocity and acceleration.
A 3D model of the robotic arm was constructed and analyzed by simulation. The positioning workspace of manipulator was constructed and analyzed.
The 3SPS-type parallel manipulator has good kinematic characteristics while performing wrist motions. The 2SPR-type parallel manipulator produced singular configuration, while performing the desired rehabilitation elbow motions, it was found to not be suitable for usage in performing rehabilitation therapy in stroke-affected patients.
外骨骼机器人通常具有多种功能，其中一种功能是为中风患者的上肢和下肢进行康复治疗。本文提出了一种新型混合（串并）机器人操作器，用于上肢康复，并对其运动学进行了系统研究。该机器人操作器旨在实现腕关节屈曲、伸展、桡偏、尺偏、肘关节屈曲、伸展、旋前和旋后运动。当代机械设计，特别是上肢外骨骼机器人的运动学结构具有一个独特的特点，即几乎所有的机器人都使用串联机器人，很少使用并联机器人。所提出的机器人的运动学结构是混合机器人（两个并联机器人串联），具有 4 个自由度。它由一个上部的 3SPS 型并联机器人和一个串联的 2SPR 型并联机器人组成。
使用雅可比矩阵和海森矩阵方法推导出机器人运动学公式，用于求解位移、速度和加速度。
构建并通过仿真分析了机器人臂的 3D 模型。构建并分析了机械手的定位工作空间。
3SPS 型并联机器人在进行腕部运动时具有良好的运动学特性。2SPR 型并联机器人产生奇异构型，而在进行所需的康复肘部运动时，发现它不适合用于中风患者的康复治疗。
