Evolved Electrophysiological Soft Robots

Abstract

The embodied cognition paradigm emphasizes that both bod-ies and brains combine to produce complex behaviors, in con-trast to the traditional view that the only seat of intelligence is the brain. Despite recent excitement about embodied cogni-tion, brains and bodies remain thought of, and implemented as, two separate entities that merely interface with one an-other to carry out their respective roles. Previous research co-evolving bodies and brains has simulated the physics of bodies that collect sensory information and pass that infor-mation on to disembodied neural networks, which then pro-cesses that information and return motor commands. Biologi-cal animals, in contrast, produce behavior through physically embedded control structures and a complex and continuous interplay between neural and mechanical forces. In addition to the electrical pulses flowing through the physical wiring of the nervous system, the heart elegantly combines control with actuation, as the physical properties of the tissue itself (or defects therein) determine the actuation of the organ. In-spired by these phenomena from cardiac electrophysiology (the study of the electrical properties of heart tissue), we in-troduce electrophysiological robots, whose behavior is dic-tated by electrical signals flowing though the tissue cells of soft robots. Here we describe these robots and how they are evolved. Videos and images of these robots reveal lifelike behaviors despite the added challenge of having physically embedded control structures. We also provide an initial ex-perimental investigation into the impact of different imple-mentation decisions, such as alternatives for sensing, actua-tion, and locations of central pattern generators. Overall, this paper provides a first step towards removing the chasm be-tween bodies and brains to encourage further research into physically realistic embodied cognition. Introduction and Background The fields of evolutionary robotics and artificial life have seen a great deal of emphasis on embodied cognition in