New approach of ultrasonic distance measurement technique in robot applications

This paper deals with the development of a prototype of an airborne ultrasonic distance measurement system applied to an autonomous mobile robot. The pivotal point of this system is the use of a wideband continuous random signal where the detection of the echo delay (time of flight) is done by cross correlation technique. Additionally a Doppler frequency shift caused by robot or obstacle movement is estimated and included in the algorithm. The major advantage of this technique is the multiple sensor interface ability at perfectly low crosstalk between each sensor unit.