Power for Robotic Artificial Muscles

Artificial muscles based on the dielectric elastomer actuator (DEA) are an attractive technology for autonomous robotic systems. We are currently exploring their use on EcoBot (Ecological roBot), an autonomous robot being developed by Bristol Robotics Lab that uses microbial fuel cells (MFCs). DEA will provide actuators for fuel cell maintenance and other goals and will increase active mission time through greater mechanical efficiency and reduced mass. Artificial muscles use high voltages and running them normally requires voltage converters to boost the voltage on delivered charge several hundred times. A dielectric elastomer generator (DEG) when used with a recently developed self-priming circuit (SPC) can supply the high-voltage power directly to artificial muscle systems. The SPC can also be started using an initial low-voltage charge from another energy harvester such as a bank of MFCs or a solar cell array. This combination could lead to a completely autonomous power source for robotic artificial muscles. We demonstrate a proof-of-concept portable self-primed DEG for harvesting wind energy from moving tree branches.