This section will talk a bit about making animal robots including 4 legged horses and cats/dogs or crawling creatures with 4 or 8 legs or slithering animals like snakes.
We need to look at nature and see the direction of the knee joint in a horse or cat or cow compared to a human.
If a creature has more than 2 legs then it is easier to balance but not super easy. With a basic robot horse you can always make sure that there are two opposing feet/hoofs on the ground.
Yes it gets complicated when you go from a walking gait to a running or galloping one.