| 摘要 |
PURPOSE:To enable the detection of a wide range of distances at a high accuracy by checking distances of an object at two points using ultrasonic waves of low and high frequencies with an ultrasonic wave transmitting/receiving means. CONSTITUTION:An ultrasonic wave transmitting/receiving means 19 provided on a manipulator 15 is used and first transmits an ultrasonic wave of a low frequency and receives therefrom to detect a rough distance to the object 21. Then, after the manipulator 15 is moved to a fixed position from the object 21, the ultrasonic wave receiving/receiving means 19 transmits an ultrasonic wave of a high frequency to the object 21 and receives it therefrom to detect the distance to the object 21. |
