Controlled Passive Walker Veronica Powered by Actuators with Independent Control of Equilibrium Position and Compliance

This paper presents the biped Veronica actuated with the MACCEPA actuator. The MACCEPA is an electrical actuator of which the compliance and equilibrium position are fully independent and both are set by a dedicated servo motor. 6 such actuators are used to power the planar biped Veronica. The control concept is based on "controlled passive walking". Instead of continuously controlling the biped, the control parameter sets for each joint are only changed a few times during walking. Between the discrete control actions the motion is passive due to the compliant actuators. So this robot behaves like an actuated passive walker. Because the compliance is adaptable, different natural frequencies can be selected. This means that the walking motion is not restricted to a fix walking speed