[en] Robot technologies for maintenance and inspection of various equipments in nuclear plants have been developed. The environment inside of the nuclear plants is very complex and out of order. Then, necessary skills for manipulators to work well in actual working environment are required to be developed. In this study, two technologies have been developed in addition to a contact moving type already developed; one is a virtual restricting type and another is a contact-restricting type. Modeling studies of the actual working environment and development of the teaching system have proceeded. Design studies on the total systems of various devices and techniques, and on the test working environment for demonstrating efficiency of the skills have also proceeded. (A. Hishinuma)