During their nocturnal activity period, weakly electric fish employ a process called "active electrolocation" for
navigation and object detection. They discharge an electric organ in their tail, which emits electrical current pulses,
called electric organ discharges (EOD). Local EODs are sensed by arrays of electroreceptors in the fish's skin, which
respond to modulations of the signal caused by nearby objects. Fish thus gain information about the size, shape, complex
impedance and distance of objects.
Inspired by these remarkable capabilities, we have designed technical sensor systems which employ active
electrolocation to detect and analyse the walls of small, fluid filled pipes. Our sensor systems emit pulsed electrical
signals into the conducting medium and simultaneously sense local current densities with an array of electrodes. Sensors
can be designed which (i) analyse the tube wall, (ii) detect and localize material faults, (iii) identify wall inclusions or
objects blocking the tube (iv) and find leakages. Here, we present first experiments and FEM simulations on the optimal
sensor arrangement for different types of sensor systems and different types of tubes. In addition, different methods for
sensor read-out and signal processing are compared.
Our biomimetic sensor systems promise to be relatively insensitive to environmental disturbances such as heat, pressure,
turbidity or muddiness. They could be used in a wide range of tubes and pipes including water pipes, hydraulic systems,
and biological systems. Medical applications include catheter based sensors which inspect blood vessels, urethras and
similar ducts in the human body.