Two-arm master/slave manipulator for nuclear facilities

Several kinds of one-arm manipulators have been developed for remote maintenance in nuclear facilities to reduce personnel radiation exposure and to keep plant availability as high as possible. In those maintenance tasks, however, there are many that need two arms, e.g., one arm holds the work object and the other arm cuts it with a plasma torch. To answer this need, a dexterous two-arm master/slave manipulator has been developed based on the technology for one-arm manipulators. A prototype two-arm/slave manipulator is shown. The specifications for master and slave manipulators are listed. The prototype two-arm manipulator is undergoing laboratory performance tests. Preliminary results showed the maximum static operating forces were 0.4 N for the all-direct drive (DD)-type arm and 1.1 N for the semi-DD type. The payload for each arm of the slave manipulator was confirmed as 10 kg/sub f/, using mock pieces. The decommissioning tasks of cutting pipes and steel plates were successfully carried out.