According to the requirements of the rehabilitation process and on the basis of the kinematic analysis of the upper
limb, there was designed variant of robotic rehabilitation device and its scheme is on fig. 3. It is an exoskeletal
system and it has seven degrees of freedom (DOF). Three DOFs are in shoulder joint, two DOFs are in elbow joint
and two DOFs are in wrist joint. Axes in shoulder joint are arranged to intersect at one point as it is in the shoulder
joint of a man. There has to be achieved a kinematic compatibility between robot and upper limb in order to avoid
undesirable action forces. In other words, it means that axes of the robot’s joints must be identical to the axes of
limb’s joints. The length of arms is adjustable.