Research of Long Range Accurate Ranging Technology Based on Ultrasonic Sensor Measurement

In order to meet the requirements of long range obstacle measurement of tower crane safety warning system and accurately estimate time of flight (TOF), an ultrasonic long range measurement system is designed and a mathematical model of echo envelope is established in this paper. Experimental data of long range obstacle measurement were collected and analyzed by using traditional threshold method and cross correlation method, the results exposed low accuracy and poor stability problems. According to the obstacle target can be quickly located by echo peak, and echo signal time domain waveform characteristics can be reflected by envelope model method, an improved long range measurement algorithm based on combination of peak method and envelope model method is introduced. Experimental results show higher accuracy and better stability of the improved long range measurement algorithm compared with threshold method and cross correlation method.