Artificial heartbeat: design and fabrication of a biologically inspired pump.

We present a biologically inspired actuator exhibiting a novel pumping action. The design of the 'artificial heartbeat' actuator is inspired by physical principles derived from the structure and function of the human heart. The actuator employs NiTi artificial muscles and is powered by electrical energy generated by microbial fuel cells (MFCs). We describe the design and fabrication of the actuator and report the results of tests conducted to characterize its performance. This is the first artificial muscle-driven pump to be powered by MFCs fed on human urine. Results are presented in terms of the peak pumping pressure generated by the actuator, as well as for the volume of fluid transferred, when the actuator was powered by energy stored in a capacitor bank, which was charged by 24 MFCs fed on urine. The results demonstrate the potential for the artificial heartbeat actuator to be employed as a fluid circulation pump in future generations of MFC-powered robots ('EcoBots') that extract energy from organic waste. We also envisage that the actuator could in the future form part of a bio-robotic artwork or 'bio-automaton' that could help increase public awareness of research in robotics, bio-energy and biologically inspired design.