Directional Hearing in a Humanoid Robot Evaluation of Microphones Regarding HRTF and Azimuthal Dependence
Gustavsson, L., Marklund, E., Klintfors, E., & Lacerda, F.
Proceedings of Fonetik 2006, the XIXth Swedish Phonetics Conference, Lund, June 7-9, 2006. Working Papers 52, Department of Linguistics, Lund University: 45-48.
As a first step of implementing directional hearing in a humanoid robot two types of microphones were evaluated regarding HRTF (head related transfer function) and azimuthal dependence. The sound level difference between a signal from the right ear and the left ear is one of the cues humans use to localize a sound source. In the same way this process could be applied in robotics where the sound level difference between a signal from the right microphone and the left microphone is calculated for orienting towards a sound source. The microphones were attached as ears on the robot-head and tested regarding frequency response with logarithmic sweep-tones at azimuth angles in 45º increments around the head. The directional type of microphone was more sensitive to azimuth and head shadow and probably more suitable for directional hearing in the robot.