Development of neuromorphic circuits with receptor cell model for animal-like gait generation using foot pressure

The authors are studying to mimic the mechanism of gait generation in animals and implement the mechanism in robots. Previously, the authors developed a quadruped robot system that spontaneously generates gait through feedback on foot pressure. The neuromorphic circuits that mimic the animal's nervous systems control the legs of the quadruped robot. Neuromorphic circuits are analog electronic circuits that output electrical spikes the same as biological neurons. However, quadruped robots system require digital processing by a microcontroller to transmit signals from pressure sensors to the neuromorphic circuit. In addition, a microcontroller drives the servo motors using a pulsewidth modulation waveform. This paper describes a newly developed neuromorphic circuit that does not require the processing of a microcontroller to convert pressure sensor signals. The authors add the receptor cell model and the integral circuit to the conventional neuromorphic circuit. By converting pressure sensor signals with the receptor cell model and the integral circuit, the neuromorphic circuit can be processed similar to a microcontroller. As a simulation and a measurement result, we confirmed that the proposed neuromorphic circuit could implement in a quadruped robot system.