A Conserved Neural Circuit-Based Architecture for Ambulatory and Undulatory Biomimetic Robots

Abstract

The adaptive capabilities of underwater organisms result from layered exteroceptive reflexes responding to gravity, impediment, and hydrodynamic and optical flow. In combination with taxic responses to point sources of sound or chemicals, these reflexes allow reactive autonomy in the most challenging of environments. We are developing a new generation of lobster and lamprey-based robots that operate under control by synaptic networks rather than algorithms. The networks, based on the command neuron, coordinating neuron, and central pattern generator architecture, code sensor input as labeled lines and activate shape memory alloy-based artificial muscles through a simple interface that couples excitation to contraction. We have completed the lamprey-based robot and are adapting this sensor, board, and actuator architecture to a new generation of the lobster-based robot. The networks are constructed from discrete time map-based neurons and synapses and are instantiated on the digital signal processing chip. A sensor board integrates inputs from a short baseline sonar array (for beacon tracking and supervisory control), accelerometer, a compass, antennae, and optionally chemosensors. Actuator control is mediated by pulse-width duty cycle coding generated by the electronic motor neurons and a comparator and power field-effect transistor (FET) system housed on low- and high-current driver boards. These circular boards are stacked in a tubular hull with the processor and batteries. This system can readily mimic the biomechanics of the model organisms by the addition of hydrodynamic control surfaces. The behavioral set results from chaining sequences of exteroceptive reflexes released by sensory feedback from the environment.

A forgotten element of the blue economy: marine biomimetics and inspiration from the deep sea

“…The latter innovation foreshadowed a modern-day buoyancy compensation device, that itself mimics the fish's swim bladder, and enables divers to closely control their buoyancy 57 . Buoyancy is a ubiquitous concern for operations at sea and underwater, and today there are a number of underwater robots, autonomous gliders and submersibles that have drawn inspiration not just from fish and their buoyancy-related movements 124 , but from marine species as diverse as whales 125,126 , dolphins 127,128 , jellyfish [129][130][131] , lobsters 129,132,133 , and copepods 134 .…”

Hydrodynamics of Biomimetic Marine Propulsion and Trends in Computational Simulations

“…Another advantage is the possibility to swim backward, simply passing the undulation from tail to head. Due to its lower efficiency compared with other BCF modes, anguilliform swimming movement has only inspired a few robots that require high maneuverability, mimicking lampreys [32][33][34][35][36][37][38][39][40][41], snakes [42], salamanders [43][44][45], eels [46][47][48][49][50][51], etc.…”

Pre-programmable pneumatic actuator: leveraging mechanical anisotropy of nonwoven fabrics with an integrated tensile sensor

“…29 The antennas of lobsters, for instance, serve as superb chemical sensors, which are adept at detecting chemical signals in intricate and dark undersea environments. 30,31 As illustrated in Fig. 1a, these antennas can provide exceptional axial flexibility and radial mechanical resilience with their unique core (organic)-shell (inorganic) structure.…”