| 摘要 |
PURPOSE:To control an ultrasonic motor properly according to the character of load torque by correcting the value of a target signal based on a state signal to be obtained through comparison between an input signal and an output signal from a piezoelectric element for detecting the driving state. CONSTITUTION:When a material grip command, e.g. a target position signal or a power signal, is fed from a manipulator system 4 to a gripper system 5, a gripper controller 5 rotates an ultrasonic motor 7 then the rotation is transmitted to grippers 81, 82. The grippers 81, 82 move in the direction of arrows and grip a material 9. Power signal or position signal is transmitted from a gripper mechanism section 8 to the gripper controller 5 and fed back to the command signal for an ultrasonic motor controller 6 in order to enable gripping of the material without causing breakdown. The gripper controller 5 sets a target position, a target power signal, a reference power signal, and the like, according to a grip command or a release command fed from the grip controller 5 then the gripper controller 5 operates command values for ultrasonic motors 4-7 based on the difference between thus set inputs and current position or power signal. |
