This proof of concept shows an interesting way of making robotic legs. They are using programmable spring actuators to make these legs function as though they had a “reflex”. The builder pulls the robot along on a leash. As the leg reaches its limit of backward motion, a signal is sent from the shoulder down to the knee that lifts it, causing it to return to the forward position. A signal is also sent to the opposing shoulder to suppress the lift reflex, keeping them from both stepping at the same time. The resulting motion is very organic feeling. We’re curious how this could be implemented in a robot which moves under its own power.