Just joined the site after reading the entry on six-wheel robot suspension by Oddbot and seeing Titan in action.
Several years ago, my dream was to participate in the Sparkfun Autonomous Robot challenge, so I jumped into building a transport platform. It worked in testing, but I quickly learned how uneven the ground is and how important suspension can be. With one or two wheels off the ground, the small bot would need a bump to get it rolling again. I also saw how much easier it went downhill versus uphill. Back to the drawing board... and the Internet.
I decided I needed more power, and probably more wheels to increase my chances of having traction somewhere. More power meant more amps, and that meant a step up from my Arduino motor shield. I bit the bullet and purchased a motor controller that could handle 12 volt motors and a fair number of amps. I decided on skid steering, so two channels would do.
Searching the Internet for platform ideas, I ran across Dagu's Wild Thumper. The demo of it crawling around the broken field effortlessly was very impressive. Sparkfun has a nice rundown of the platform here.
Not having an extra $300 on hand, I decided to put together a homemade version of the wild thumper. I bought a $60 Sabertooth 2x5, some 125 oz/in gearmotors with matching wheels. Then I hit the local Home Depot for some PVC pipe for a frame. I found PVC tees an almost perfect fit for my motors. But I never could get the suspension right.
I'm sure you know the story... I set it aside "for now". After seeing the explanation and the clothespin spring, I am again inspired to get my guy running!
I'm working towards a gardenbot that will push a lawnmower deck. Will be more fun to play in the yard rather than mow it manually!