An Analog CMOS Circuit Implementing CPG Controller for Quadruped Walking Robot

In this report, we propose an analog circuit that implements a locomotion controller for a quadruped walking robot. Animal locomotion, such as walking, running, swimming and flying, is based on periodic rhythmic movements driven by the biological neural network, called the central pattern generator (CPG). In recent years, many researchers have applied the CPG to locomotion controller for walking robots. However, most of these have been developed with digital processors, and thus have several problems, such as high power consumption. Hence, we designed an analog CPG controller for the quadruped walking robot. The proposed circuit is based on the Amari-Hopfield model, which is suitable for analog circuit implementation because of its simple transfer function. Since the proposed circuit is constructed from complemental metal-oxide semiconductor (CMOS) devices, which operate in their subthreshold region, it can reduce power consumption. By computer simulations, the proposed circuit is shown to have the capability to generate several periodic rhythmic patterns and transitions between their patterns promptly.