A segmented manipulator arm for a nuclear reactor vessel inspection device is disclosed. The several segments of the arm are linked in a manner which permits independent movement of each segment in a different plane of motion. The transducer array which is utilized to conduct the examination of any appropriate point in the reactor vessel is cooperably linked to the final or most forward segment of the manipulator arm.The first segment of the manipulator arm is appropriately coupled to the main column of the inspection device for independent movement in one of three planes relative to the main column. Additional segments are employed and cooperatively linked to the first segment to yield a total of nine planes of movement for one or more of the segments. In addition, brackets are used to constrain segment movement in parallel or predetermined planes as desired.