The human body goes further than that too, when you're out jogging - as your foot approaches the ground for a stride, you slow the velocity of your foot downwards towards the ground so there's less of a sudden deceleration.
replyImagine when you throw a tennis ball high in the sky, and then you catch it on your racket without bouncing by matching it's velocity, your feet do the same thing with the ground on a smaller scale.
Then you have several hinges absorbing/dissipating that energy if you're using good form: foot flexes with a pivot in the arch of your foot, calf/achilles stretches with a pivot in your ankle and quad with a pivot in your knee. It should look like an angled, backwards Z at strike with nothing just straightened and tanking the impact.
replyNobody actually runs perfectly enough to take 100% of the impact out of your joints but good form routes as much as possible into the muscles/ligaments around the joints instead of straight through them. It's a lot of little bitty unconscious nerve endings and muscles so one could expect it will take a while to iron out for robots.
Thinking about it more, maybe the issue here is that there's no self-healing stretchy ligaments involved in robots to begin with, even before the control issue.