Gumpy the off-road robot
My first full project. This is a suprisingly capable little robot built on top of a R/C crawler chassis I found at a local thrift store. It can handle hills and long grass with ease. A wireless PS2 controller and a Pololu TReX Jr. motor controller makes it very responsive. With two drive motors and one steering motor this bot can generate pretty good torque and still has room for expanding the onboard electronics with things like GPS, accelerometer, gyroscope, etc.
The power source is a 9.6V 1600 mAh NiMH R/C battery pack for the motor driver. It works okay, but a 2000+ mAh will definately give it the kick to go up stairs and tackle much rougher terrain. Future (possible) modifications will probably include stronger motors, a wireless camera, mixed autonomous/human control, and a revamped suspension system.
Since I had a hard time finding code for the TReX Jr I decided to share my code in the hopes that it will make it easier for a beginner to interface a TReX to an arduino: PS2 motor control. I'm working on a full tutorial but until I get it posted I think the code shall suffice.
~UPDATE: Well, I was going to post a video but than I realized that the steering system broke. My guess is that a cheap R/C car has a hard time handling the forces of sudden turns that the motor controller is capable of providing. When I turn, the gears that turn the wheels slip, causing a very annoying grinding sound and preventing the wheels from fully turning. So a note and a word of caution, if you use cheap parts don't overexert them more than they are meant to. The easiest solution is to program some kind of safety into the code until you determine how much stress the vehicle can withstand.
I might try to replace the entire steering system with a more reliable servo instead of a toy motor, however that is gonna take a lot of carving.