Abstract
A radio frequency (RF) telemetry system with a shape memory alloy (SMA) microelectrode was designed and fabricated. The total size and weight are 15×8mm and 0.1g without batteries. Since the telemeter is small and light enough to be loaded on a small animal such as an insect with no restraint on motion, the system can work for the neural recording of a free-moving insect. The SMA microelectrode fabricated by microelectromechanical system (MEMS) technologies can easily attach to the nerve by electrically actuating the electrode structure. Also, it does not detach from the nerve during motion due to its clipping structures. The telemeter can transmit signals by frequency modulation (FM) transmission at 80-90MHz. The transmitted signals can be received about 16m away from the telemeter with a high S/N ratio. The neural activity can be detected without attenuation using an instrumentation a mplifier with input impedance set to 2MΩ at 1kHz. The telemeter was loaded on a cockroach and the neural activity during free-walking was successfully measured through this telemetry system.
