See "Toddler learning to walk" at http://groups.csail.mit.edu/locomotion/videos.html (2004). At first, the robot walks passively down an inclined treadmill. But it quickly learns how to efficiently add just a little bit of power from its motors at the right time each stride, such that it soon walks on level ground and adapts to different surraces.
So it does use a power source. The title should read - "Robot walks downhill without additional power source".
You thought someone invented a perpetual motion machine?
Thanks for taking the thermodynamics-defiance out of the robot and replacing it with kinetic energy over time.
We could go downhill with (almost) no power too, if only we could coast-run fast enough (and could handle the shock in your leg when your stride becomes so long you fall several feet with each step)
and could handle the shock in your leg when your stride becomes so long you fall several feet with each step
This is possible when running down a steep sand incline. Very fun.
True, but doesn't this mean that biped robots wouldn't be required to expend energy when walking downhill? Depending on the application, it can greatly increase the time that a robot can be in use.
It might be pretty difficult to build a robot that can both walk passively downhill, and walk actively uphill.
Can that thing walk downhill over an uneven terrain?
BigDog was able to go both uphill and downhill, as well as even be kicked from the side while maintaining balance. Good point regarding being passive, I figured that somehow the robot would figure out the slope and provide extra power when the terrain was uneven or if it would be unable to maintain a given speed passively.
BigDog didn't walk downhill passively, did it?
No, it didn't. Sorry if that's how it came across - I was just supposing that this concept could be use to extend the life of a robot such as BigDog or others by controlling how passive it was in response to downhill slopes.
You just need one of those Escher staircase thingees...