ULTRASONIC RANGING DEVICES

摘要

An ultrasonic ranging device suitable for use as a sensor on a mobile robot, the device comprising a transmitter (9) for transmitting in a scanned fashion a beam of ultrasonic energy over a target region of interest (11), a detector (13, 14) for detecting return ultrasonic energy comprising reflections of the transmitted beam from the target region and a signal processor (17, 19) for enhancing the signal detected by the detector, which processor comprises a correlator (19) for correlating the signal output from the detector with a reference signal wherein the reference signal is a representation of the actual signal which has been produced by that detector when the transmitted beam has reflected at normal incidence from a plane reference target surface of interest, the processor also including a computer store (21) for storing said signal representation and applying the same as a reference signal to said correlator (19) during detection of a signal representing reflection from a target to be detected.