A NEW ALGORITHM FOR THE USE OF AN ANTHROPOMORPHIC ROBOT MANIPULATOR ARM IN REMOTE AND LABORATORY NDT APPLICATION

Abstract Published studies of serial link arm usage for the manipulation of sensors in NDT are rare, perhaps because there is a perception that the cumulative errors in spatial location along such arms are too great for satisfactory imaging. These errors, with good programming. are not as serious as they might seem at first sight and the flexibility of serial arms is most attractive. This paper shows that a serial link robot manipulator ann can be used to perform raster scans (as used in ultrasonic c-scanning) with precision in spatial resolution as good as is required in the NDT industry and normally achieved by means of conventional x-y cartesian scanners. It also presents an iterative method to compute the inverse kinematics (ie the programme of sequence of joint angles) needed to constrain a serial link robot manipulator to perform an NDT scanning operation (eg to perform a plan or raster scan whilst maintaining a constant angle between the probe and the surface under inspection). The iterative method...