Meeting Abstract
Metazoans are composed of hierarchically organized living systems (cells). These populations form subunits (tissues and organs) which work together to accomplish tasks which the individual subunits cannot. To discover principles by which simple robots can be integrated to form more complex robots, we developed a stochastic locomotor composed of simple non-motile robots. We refer to the subunits as smart-active particles, or “smarticles”. Smarticles (14 cm long) are 3D printed, three-link two degree of freedom robots with simple sensory capabilities (sound, light). The outer link positions are controlled by servo motors and can perform gaits (periodic closed trajectories in the 2D configuration space) or hold a configuration. Each smarticle is incapable of individually displacing or rotating. However, when confined inside an unanchored 20 cm plastic ring, smarticle ensemble (which we refer to as a “supersmarticle”), can displace through collisions among active smarticles and the ring. When all smarticles are active (performing gaits) the supersmarticle randomly diffuses with no favored direction. By introducing sensory capabilities — a photoresistor to detect light levels and reactive behaviors based on the sensing — the supersmarticle can achieve directed motion: when a smarticle detects light it stops its gait and holds in a straight position. This asymmetry generates stochastic but directed motion either towards or away from the inactive smarticle with an average drift speed of ~1 cm/s. The ring to inactive smarticle mass ratio determines the motion direction. A 1D simulation of the supersmarticle, which represents the active smarticles as a fluctuating mass, predicts the supersmarticle’s movement in the frame of the inactive particle.
