Like sonar, but not submerged.
Waves transmitted, reflected, received. Add special magic and we have a map of the surroundings…
This project seeks to create this special magic.
Speed of sound in air: V = 331.4 + 0.6T_c ← speed of sound [m/s], temperature in Celcius
https://secure.wikimedia.org/wikipedia/en/wiki/Speed_of_sound
https://secure.wikimedia.org/wikipedia/en/wiki/Sound_dampening
http://www.americanpiezo.com/standard-products/air-transducers/ultrasonic.html
http://www.americanpiezo.com/standard-products/air-transducers.html
Cyclone III kit til 1528: http://dk.farnell.com/altera/dk-start-3c25n/starter-kit-cyclone-iii-fpga/dp/1428131
EP3C25 FPGA: http://www.altera.com/products/devices/cyclone3/overview/cy3-overview.html (25k LEs, 66 M9k mem, 594 kBit embedded memory, blocks, 66 18×18 bit mults),
Cyclone II kit til 1295: http://dk.farnell.com/altera/dk-cycii-2c20n/kit-fpga-cyclone-ii-development/dp/1560812 , den er dog noget slanket i forhold til Cyclone III ovenfor.