Smart Sensing Strategies: Insights from a Biological Active Sensing System

Biological sensory systems efficiently and reliably monitor changes in real-world environments that are relevant to an animal’s specific behavioral needs and goals. Understanding the sensory mechanisms and information processing principles that biological systems utilize for sensory data acquisition may provide useful guidance for the design and implementation of smart sensing systems in diverse engineering applications. Certain freshwater fish from South America and Africa, known as weakly electric fish, use self-generated electrical energy to actively probe their environment. The fish emit millivolt-level electrical discharges and detect microvolt-level voltage perturbations arising from nearby objects in the water. The fish are able to detect and localize targets in 3D space and assess target characteristics such as size, shape and electrical impedance. This electrolocation ability enables the fish to hunt and navigate at night and in turbid waters without the use of visual cues. To achieve reliable, real-time performance, the nervous system implements a number of smart sensing strategies, including efficient encoding, multiscale virtual sensor arrays, task-dependent filtering and online subtraction of sensory expectation.