Developments on the air rig
Latest research results for 2008
- Acoustics modelling of bat echolocation [PDF]
- The simulation of bat-orientated auditory processing using experimental data of echolocating signals [PDF]
- Human localisation using echolocation [PDF]
Research results for 2007
In order to research improvements in resolution using medium frequency ultrasound in air, the University of Southampton’s Institute for Sound and Vibration Research (ISVR) have built an air experimental rig. The first version of the rig has been built as a “reduced complexity” measurement facility that involves minimal cost and time requirements with general-purpose equipment already available. The purpose of this first version of the rig was to validate the basic principles of the experimentation functionality and to identify any weaknesses and bottlenecks in its design. A complete set of object Impulse Responses has been collected. This measurement database contains data for 7 objects (discs) of different dimensions, for different rotations and distances relative to the source and receiver.
The air rig in ISVR’s small anechoic chamber. The apparatus allows the positioning of an object in line with a source and a receiver and recording of the backscattering impulse response. The obtained results are then equalised with respect to the free field response of the transducers.
Objects used in backscattering experiments in the air rig.
Measured backscattering impulse responses of a 10cm diameter Perspex disc for rotations of 0o (flat face facing the source and receiver) up to 90o (circular surface facing the source and receiver) in 15o increments.
A gap exists in previous research in terms of relating the bat’s auditory capabilities and the modelling of its auditory physiology to the physical aspects of the echolocation process. The objective now is to determine the input signals to the bat’s auditory system during the process of echolocation.
