People with hemiplegia require ongoing rehabilitation exercises to regain function in their upper limbs. However, due to the increasing number of elderly and disabled people, the number of rehabilitation professionals is insufficient. As a solution to this problem, researchers have been exploring various upper limb rehabilitation exercise robots. Unfortunately, these robots are often large and heavy, making them cumbersome to wear and use. The proposed exoskeleton rehabilitation robot consists of two robotic modules: an elbow module (1 DOF) and a wrist module (1 DOF). In order to analyze the robot"s workspace, the kinematics were calculated using the D-H parameters. To generate the trajectories, five able-bodied individuals wore the robot and performed the hand-wash motion, resulting in a total of 10 trajectory data sets. The reference trajectories were then generated by polynomial regression based on the collected data. Lastly, a passive mode control was experimented with in the rehabilitation process, and the results demonstrated the promising effectiveness of the proposed robot.

Various types of 5-axis machine tools have been developed. In the case of a machine tool composed from linear motion, the kinematic equation can be obtained easily and intuitively. However, machine tools with more than four axes, including rotating axes, have generally performed kinematic and dynamic performance analyses using mathematical methods. In this paper, the kinematic equations of various types of machine tools are obtained, based on the Homogeneous Transformation Matrix method. The loop stiffness was then calculated as a mathematical model. A mathematical model of loop stiffness was verified by using a method to calculate the loop stiffness of a commercial program. The results of the mathematical model showed less than a 1% error with the commercial program, and this could show the validity of the mathematical model. Then, this model was applied to two types of machine tools. The minimum loop stiffness of both models is compared.