I hate to be the one to break to this to you, but your robotics teacher was off his or her rocker or was trying to make a much larger point with a bad example.

If walking was simply graceful falling, it would imply that once we begin the process of "falling" onto the next foot, we couldn't significantly affect the outcome. However, because I can start walking and then stop with a single leg half way between it's highest point and the ground, this explanation of walking as falling becomes very problematic.