THEME - Hard & Soft 1999
Sound Controlled Vehicle Project
To design and construct a vehicle that can
automatically follow a path defined by four different sound sources. You will also design the sound sources.
The vehicle will consist of a pair of geared DC motors to provide
propulsion and steering, a directional microphone to monitor the sounds, a DSP card to process and analyze these sounds and a motor card to provide adequate power for the motors.
ADSP EZ-KIT Lite DSP card - this is the main vehicle controller card, details of which are given in the Analog devices books provided.
Motor Driver Card is a custom made board for the vehicle
project and provides the following facilities: four high current outputs (6V/500mA) to control the two drive motors; generates a single variable pulse width modulator (PWM) for motor speed control; provides
two high current general purpose outputs (6V/300mA); provides a regulated supply for the microphone board.
A control program is required which will monitor the signal received from the
directional microphone, identify the different sound sources and drive the vehicle to each one in turn. You have complete freedom to design and develop this software as you wish. You also have some freedom
to design the sound sources.
Simple sound recognition can be done by comparing the frequency spectrum to a set of known spetrum patterns (templates) stored in memory. Each template would contain the key
frequency components of the sound that represents a particular sound source. If a sound is found to match one of these templates, then the corresponding sound source has been recognised. Software is supplied
to assist with this, if you wish to use it.
Another approach to sound source recognition would be to use digital filters to analyze the sounds.
You may wish to design a more sophisticated system.
The pseudo-code below show in a simplified form the stages required for the controlled vehicle.
while (infinite) do
Perform FFT on data
if (* it is a sound source) then
Output appropriate data to motor port