Sugar powered autonomous robot
Ecobot I is a 960g robot, powered by microbial fuel cells (MFCs) and performs a photo-tactic (light seeking) behaviour. This robot does not use any other form of power source such as batteries or solar panels. It is 22cm in diameter and 7.5cm high.
The biocatalyst in the MFCs’ anode was a freshly grown culture of E. coli fed with refined sugar whereas the catholyte was ferricyanide. Methylene blue (MB) was used as the redox mediator to extract a portion of the electrons produced from breaking down the sugar in the metabolic pathways of E. coli. Electrons are then transferred to the anode electrode and flow through the external electrical circuit to the cathode, thus producing electrical current.
Energy produced by the MFCs is stored by an onboard 'accumulator' consisting of a bank of capacitors. Two photo-diodes provide the input to the "tracking system" of the robot and are indirectly connected to two high efficiency, high torque motors.
Once the energy is accumulated up to a specific threshold, it is then released to either or both of the motors according to the indication from the photo-diodes. The system does not employ any other form of power supply such as batteries or solar panels.
Ecobot I diagram
Our study builds on the foundation work of Stuart Wilkinson (Gastronome, 2000) at the University of South Florida.
- Dr Ioannis
Tel: +44 (0) 117 32 86318
Tel: +44 (0) 117 32 86322
BioEnergy and Self Sustainable Systems
Bristol Robotics Laboratory
University of the West of England
Bristol, BS16 1QY