Using ultrasonics for sensing in a robotic environment

A system based on pulsed ultrasonics is developed to be applied for sensor feedback in robotics. A sensor device consisting of four 40-kHz transducers mounted around one 200-kHz transducer is designed. By changing the frequency between 40 and 200 kHz for the ultrasonic excitation, the range of the distance measurements is significantly increased while the accuracy is maintained. The system can perform distance measurements as well as space orientation and object identification among a limited number of possible forms. Particular algorithms are developed to detect the front of the reflected echo of the ultrasonic transducers. A special computer interface has been designed for fast sampling of the ultrasonic signals. The system is built around a laboratory robot platform. Experimental results of both object identification and sensor based feedback are described