Taking all the found facts into account, we determined X, Y, Z and W as followings. X and Y are people with physical disability who can not move one arm owing to amputation, or joint disease, or deformation, or peripheral nervous disability and people with brain trouble who can not move one side of the limbs owing to cerebral paralysis, or spastic paralysis whereas they can move freely the other arm and hand. As for Z, robot arm will assist the above PWD to do circuit test of people with brain trouble and soldering inspection and repairing of people with brain trouble shown Fig. 3. These tasks are carried out at a working table with a conveyor line in Mugunghwa Electronics, the factory only for handicapped workers, and we set there as W.