GPS-Free Maintenance of A Free-Space-Optical Link Between Two Autonomous Mobiles
This paper presents a method for measuring the relative position and orientation between two mobile robots using a dual binaural ultrasonic sensor system. Each robot is equipped with a sonar transmitter that sends signals to two receivers mounted on the other robot. It is assumed (but not implemented in our tests) that the two robots can synchronize events with an infrared or radio link. The receivers measure the distance to the transmitter on the other robot, and a geometric model determines the relative position and orientation of the two robots based on a combination of the data from all four receivers. This paper describes the theory and experimental set-up to test this technique. Experimental results show the accuracy and operational limitations of the technique.