Layered control architectures in robots and vertebrates

We review recent research in robotics, neuroscience, evolutionary neurobiol ogy, and ethology with the aim of highlighting some points of agreement and convergence. Specifically, we compare Brooks' (1986) subsumption architect ure for robot control with research in neuroscience demonstrating layered c ontrol systems in vertebrate brains, and with research in ethology that emp hasizes the decomposition of control into multiple, intertwined behavior sy stems. From this perspective we then describe interesting parallels between the subsumption architecture and the natural layered behavior system that determines defense reactions in the rat. We then consider the action select ion problem for robots and vertebrates and argue that, in addition to subsu mption-like conflict resolution mechanisms, the vertebrate nervous system e mploys specialized selection mechanisms located in a group of central brain structures termed the basal ganglia. We suggest that similar specialized s witching mechanisms might be employed in layered robot control architecture s to provide effective and flexible action selection.