Abstract: A reorientation device for use with a general purpose object manipulator is disclosed, comprised of an arrangement for rotating the object while in the grasp of the manipulator through predetermined detented angles, this reorientation thereby reducing the range of manipulation motions required to be executed by the manipulator device. The specific reorientation arrangement includes pneumatically operated rack and pinion devices adapted to rotate turnover plates through a 180.degree. angle, each of the turnover plates being adapted to carry a respective one of a set of manipulator fingers. By means of a pneumatically operated interposer pin, the rotation of each turnover plate can be selectively arrested at a predetermined angle of rotation short of the full degree of rotation produced by the rack and pinion devices.