Echolocating big brown bats emit frequency-modulated (FM) biosonar sounds and listen for echoes to perceive their surroundings. They determine how far away targets are from echo delays and distinguish among targets by their shape from echo spectra. Their biosonar is both fast and robust, which makes it valuable for developing real-time, biologically inspired guidance systems for vehicles to operate without vision. Our goal is to develop a processing framework for a biologically-inspired autonomous guidance control system that can identify targets, steer flight, and control the emission of successive broadcasts, all while avoiding interference from surrounding clutter. The project is based on the Spectrogram Correlation and Transformation (SCAT) model of biosonar. This model is a computationally-unified auditory description of biosonar as a real-time process for target ranging from echo delay and shape perception from the echo spectrum. Critically, the broadcast-echo comparisons are not being done with conventional correlation methods used in sonar. Instead, broadcast and echo pairs are processed by coincidence-detector networks applied within numerous parallel frequency bands, each containing a neurally-inspired delay-line. The model uses propagation delays for target range and a novel, deconvolution-like transformation of echo spectra into images that depict the spacing between individual reflecting points (glints) in the target. It can detect and locate objects with a variety of glint separations in centimeters but is scalable in terms of frequency band, operating range, and target size.
Haro, Stephanie, and Simmons, James A.,
"Sonar processing framework based on the SCAT model of bat biosonar"
(2016).
Summer Research Symposium.
Brown Digital Repository. Brown University Library.
https://doi.org/https://DOI: 10.7301/Z0DF6P52
Each year, Brown University showcases the research of its undergraduates at the Summer Research Symposium. More than half of the student-researchers are UTRA recipients, while others receive funding from a variety of Brown-administered and national programs and fellowships and go …
