1994

Penttinen, Auvo; Graeffe, Jussi

Ultrasonic sensors are widely used for proximity sensing and environment modeling in mobile robots that are used indoors. The present work was conducted in the open air, and tests showed that in outdoor applications the performance of ultrasonic sensors is generally corrupted by the nonideal nature of the propagation medium, i.e., air. Even in good weather conditions variations in sound velocity occur in outdoor air, making echoes behave randomly and worsening range resolution. This may present a severe drawback for the outdoor use of advanced airborne imaging methods since compensation for this phenomenon is difficult. This work was done within the framework of the ESPRIT II Panorama-project.