Just curious question, is cat version 5 and 6 in this video https://www.youtube.com/watch?time_continue=87&v=iGEdF5QsDB8 using 3 servos per leg, or third part of leg is connected only using link ? Thanks :)
It's hard to evaluate. It does look better but also introduces structure and algorithmic complexity.
Is the Ankle making walking any better or it is mainly design feature ?
Yes, shoulder roll + shoulder pitch + knee pitch. Ankle pitch is passively connected by link. There's another DoF at paw.