A 12-bit analog-to-digital converter (LTC1298) on the microprocessor carrier
board converts the DC signal from each receiver for processing by an embedded
controller. The software of the microprocessor compares the signal strength
of the two front receivers to determine which direction to turn the puppy.
Comparisons are made between the front and rear receivers to see if the puppy
needs to make a 180 degree turn. Pulse-width modulation is produced by the
microprocessor to activate the steering servo. The pulse-width driving the
steering servo is proportional to the signal differential of the two front
receivers. An H-bridge circuit allows control of higher currents and provides
forward and reverse capabilities required by the drive motor. A buffer amplifier
is used to isolate the pins of the microprocessor from the circuits being controlled.
Abstract and Introduction
Ultrasonic Transmitter
Ultrasonic Receivers
Infrared Proximity Detector
