Here is my Less-is-MoreBot.
Ever since I started using the Picaxe chips, I started to wonder how far you could take the -08M. I made this robot to squeeze about all I could out of a single -08M chip. The idea became the Less-is-MoreBot. Starting with the #AXE021 Proto board, I added female headers to make it more prototype friendly.
I had a good CD drive motor so it was used for to power the Bot. I made the aluminum gearbox at work using some leftover slotcar drag-racing gears. These are 64 pitch gears and available in pinion sizes from 6-tooth to 16 tooth and spur sizes from around 46 teeth to 62 teeth. You can get them from any slotcar track that features drag racing. The pinion gears have a 2mm bore and the spur gears use .093 inch bore. The double reduction gearbox has a 16:1 overall ratio. Tires are 1.0" diameter.
Motor control is FWD-Stop-REV using half of a L293D chip. This chip is mounted on a RK Education Motor Control PCB. I like this board as the size is 35mm square and has (3) mounting holes. Pretty easy to place almost anywhere. Screw terminals add to the ease of wiring and moving to other projects. This board is wired to the chip Pins 2 and 4.
A Futaba standard servo is wired to Pin #0 thru a 330 ohm resistor. I use the servo to steer the Bot and also sweep the Sharp sensor. Some more slotcar parts were used for front wheels. I made the front steering from brass and aluminum tubing and sensor mount from aluminum angle. Steering is 45 degrees each way from center.
Object detection is the Sharp #GP2D120 sensor wired to Pin #1. Still have the Input #3 pin empty but I am thinking of something to add soon so that all 5 available pins are used..