Variable aperture sonar for mobile robots

This paper describes a system for controlling an array of sonar transducers to improve range data quality and speed of acquisition. The key element of this system is the control it exerts over the effective sensing volume of each transducer (variable aperture). A circular sonar array is arranged so that the sensing volumes of the transducers overlap each other for at least one aperture setting. The system produces range data that are more consistent over time by combining sensor arrangement, range data analysis, manipulation of sensor firings and control of sensing volumes. The result is more reflective of the targets in the environment as compared to conventional sonar array control techniques. The technique is also fast, requiring one or two firings of all sensors to provide the improved range data