Applying von Mises Distribution to Microphone Array Probabilistic Sensor Modelling
Conference: ISR/ROBOTIK 2010 - ISR 2010 (41st International Symposium on Robotics) and ROBOTIK 2010 (6th German Conference on Robotics)
06/07/2010 - 06/09/2010 at Munich, Germany
Proceedings: ISR/ROBOTIK 2010
Pages: 7Language: englishTyp: PDFPersonal VDE Members are entitled to a 10% discount on this title
Markovi?, Ivan; Ivan Petrovi? (University of Zagreb Faculty of Electrical Engineering and Computing, Croatia)
This paper deals with the problem of localizing and tracking a moving speaker over the full range around the mobile robot. The proposed algorithm is based on estimating the time difference of arrival by maximizing the weighted cross-correlation function in order to, by series of geometrical calculation, determine the azimuth angle of the detected speaker. A post processing technique is proposed in which each of these microphone-pair determined azimuths are further combined into a mixture of the von Mises distributions, thus producing a practical probabilistic representation of the microphone array measurement. It is shown that this distribution is inherently multimodal and that the system at hand is non-linear, which required a discrete representation of the distribution function by means of particle filtering. Experiments were conducted and the results show that the algorithm can reliably and accurately localize and track a moving sound source.