| 摘要 |
PURPOSE:To reduce hysteresis of an actuator due to dither effect and to detect a fault by inputting an in-phase external disturbance signal to a drive circuit of rubber artifitial muscle actuators arranged oppositely. CONSTITUTION:Since the frequency of the external disturbance signal 120 added to a bias pressure signal 102 is sufficiently higher than the band width of a drive circuit and in phase, the inner pressure 107 of the rubber artificial muscle actuator 7 is pulsated in-phase and acts like dithering without giving effect on a turning angle of an arm 10, then the hysteresis of the rubber artificial muscle actuator 7 is reduced. On the other hand, a servo valve drive signal detection signal 121, a pressure sensor signal 12-2 and a load cell signal 123 are inputted to a safety device 21 and various faults are detected through the combination of these signals and the external disturbance signal component independently of the level of the servo signal extracted from the servo signal. |
