TY - CONF T1 - Control and design of the spherical pointing motor T2 - , 1993 IEEE International Conference on Robotics and Automation, 1993. Proceedings Y1 - 1993 A1 - Bederson, Benjamin B. A1 - Wallace,R.S. A1 - Schwartz,E.L. KW - absolute positioning device KW - Actuators KW - camera sensor KW - CAMERAS KW - Coils KW - electric actuators KW - electric motors KW - Magnetic field measurement KW - Magnetic sensors KW - Open loop systems KW - open-loop control KW - orthogonal coils KW - pan-tilt actuator KW - permanent magnet KW - Permanent magnet motors KW - Permanent magnets KW - position control KW - Scanning probe microscopy KW - second order system KW - spherical pointing motor KW - velocity control KW - Velocity measurement KW - velocity measurements AB - A miniature pan-tilt actuator, the spherical pointing motor (SPM) has been built. The SPM is an absolute positioning device, designed to orient a small camera sensor in two degrees-of-rotational-freedom. It is 4 cm×5 cm×6 cm and weighs 160 g. The operating principle of the SPM is to orient a permanent magnet to the magnetic field induced by three orthogonal coils by applying the appropriate ratio of currents to the coils. The open-loop control and design of the SPM are described. Physical characteristics and velocity measurements of the prototype are reported. The SPM is modeled with a simple second order system. Without control, it oscillates substantially when a single impulse is applied. By applying a second impulse without feedback, the oscillation can be reduced by as much as a factor of ten JA - , 1993 IEEE International Conference on Robotics and Automation, 1993. Proceedings PB - IEEE SN - 0-8186-3450-2 M3 - 10.1109/ROBOT.1993.291888 ER -