Controlled passive actuation: concepts for energy efficient actuation using mechanical storage elements and continuously variable transmissions

Walking robots consume more energy for locomotion than their wheeled and tracked counterparts. To achieve energy autonomous operation, a robot needs to run on energy that is harvested from its environment. In this light, it is meaningful to address reduction of energy consumption. The contribution of the research discussed in this thesis is twofold. Firstly, we increase insight in the mechanisms of energy loss by supplementing prior work with an analysis of the energetic losses in electric actuators. Secondly, we made steps towards the reduction of energy losses by including a mechanical storage element (a spring or flywheel) and a Continuously Variabel Transmission. We have named this actuation concept Controlled Passive Actuation and experimented with two setups to prove the concept. As part of this effort, two novel designs of Continuously Variable Transmissions are discussed.