Design of an exoskeleton robot for rehabilitation of people with movement disabilities

In the nearly six decades, exoskeletons have progressed from the stuff of science fiction to nearly commercialized products. In addition, the main part in usage of these robots in the medical sciences and particularly for the rehabilitation, specially disabled and elderly people is to help them to do their basic routine activities like walking, sitting and etc. This article represents the design process of a lower limb exoskeleton robot for helping disable people in gait cycle. First, the conceptual design of 7 Degrees of Freedom (DoFs) robot, consist of 3-DoFs in each leg and 1-DoF in hip joint, is presented. Then the dynamic modeling of mechanical system is shown by Lagrange Method. In addition to producing an optimized mechanical model of the exoskeleton, it was necessary to ensure the strength of each component. So that after the force analyzing of the robot components which are designed for the lower limb extremities, the physical output information of the modeling software (CATIA) is used as the dynamic model input and also in order to obtain motion equation in the gait cycle always needed to choose an appropriate coordinate for simulating closer to reality. In continuation of discussion a combined controller is designed to investigate its performance. Finally the system results are shown the maximum torque of 1st joint is 32 N.m, the 2nd joint is 13 N.m and the 3rd joint is 3 N.m. The maximum torques lead to select the suitable actuator for each link of robot.