The Climber - Third ride - It works!!!!!

I can imagine that as 1 foot(toes not inches) of a full standing robot walking up stairs with the ankle above the controller board,

don't ask me how it could balance but it would look awsome if it could work.

So the problem with the first and last stairs have to do with the weight distribution, I think.

during mid-flight, (i.e. flight of stairs...um. another bad pun..), the rear wheels are taking about 70% of the weight (square root of 2, assuming that the robot is at 45 degrees!), rather than half of the weight. In the case of the last step,  the downward weight vector on the front wheel is much smaller than it is while it's climbing, i.e. it's not pulling "up" as strongly, so has relatively smaller traction.

So you need to either have some way to dynamically change the weight distribution, which would make it more complex, or you could try using "stickier" rubber on the wheels - that would increase the normal forces that are the traction.

There's an important point here, in response to one of your comments - adding rubber spikes to the wheels actually DECREASES your traction, this is because by using spikes, you decrease the amount of contact between the wheel and the ground. If you want maximum traction, you need very smooth, sticky rubber - this is exactly why formula 1 race cars have "slicks", which provide maximum traction with the ground.

For the first couple of seconds just make the back wheels a little bit faster than the front.

(or the other way not quite sure of my logic)

The wheels appear to have enough traction - maybe it just needs more "Push behind" than "Pull infront" for the first part or visaversa.

once its underway (maybe by tilt switch) it can revert to same speed back and front.........

I think this is a very nice design but your problem is not weight or power but traction, you need more wheels.

here is a video of a similar robot that has overcome the problem with more wheels:
http://www.youtube.com/watch?v=mW4LJW6j05E&feature=channel_page

I think i found a solution, its really comes in a game where you need to go over obstergoals, and then i juse that tactic, but to the subtjek. http://img208.imageshack.us/img208/9208/60319307.png There you see the front, that it does is when it hit the first wheel then it will lift up, but you need some thing to hold it, but you need lots of power. Then i put that arrow to see that when the secound wheel hit then you got exstra power....

Hope THIS helps :)