In the area of biomimetics, engineers use inspiration from natural systems to develop technical devices, such as sensors. One example is the lateral line system of fish. It is a mechanoreceptive system consisting of up to several thousand individual sensors called neuromasts, which enable fish to sense prey, predators, or conspecifics. So far, the small size and high sensitivity of the lateral line is unmatched by man-made sensor devices. Here, we describe an artificial lateral line system based on an optical detection principle. We developed artificial canal neuromasts using MEMS technology including thick film techniques. In this work, we describe the MEMS fabrication and characterize a sensor prototype. Our sensor consists of a silicon chip, a housing, and an electronic circuit. We demonstrate the functionality of our μ-biomimetic flow sensor by analyzing its response to constant water flow and flow fluctuations. Furthermore, we discuss the sensor robustness and sensitivity of our sensor and its suitability for industrial and medical applications. In sum, our sensor can be used for many tasks, e.g. for monitoring fluid flow in medical applications, for detecting leakages in tap water systems or for air and gas flow measurements. Finally, our flow sensor can even be used to improve current knowledge about the functional significance of the fish lateral line.

Beetles of the genus Melanophila acuminata detect forest fires from distances as far as 130 km with infrared-sensing organs. Inspired by this extremely sensitive biological device, we are developing an IR sensor that operates at ambient temperature using MEMS technology. The sensor consists of two liquid-filled chambers that are connected by a micro-fluidic system. Absorption of IR radiation by one of these chambers leads to heating and expansion of a liquid. The increasing pressure deflects a membrane covered by one electrode of a plate capacitor. The micro-fluidic system and the second chamber represent a fluidic low-pass filter, preventing slow, but large pressure changes. However, the strong frequency dependence of the filter demands a precise characterization of its properties. Here, we present a theoretical model that describes the frequency-dependent response of the sensor based on material properties and geometrical dimensions. Our model is divided into four distinct parts that address different aspects of the sensor. The model describes the frequency-dependent behaviour of the fluidic filter and a thermal low-pass filter as well as saturation effects at low frequencies. This model allows the calculation of optimal design parameters, and thereby provides the foundation for the development of such a sensor.

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The beetle Melanophila acuminata uses a specialized organ to detect infrared radiation. The organ consists of about 100 individual sensilla. The main component of the sensillum is a pressure chamber. Upon absorption of radiation, the pressure increases, and the tip of a dendrite is deformed. A unique feature of the organ is a compensation mechanism that prevents large pressures. The beetle uses this organ to detect forest fires and to navigate inside burning woods. However, the sensitivity is part of a long-lasting discussion, providing thresholds between [Formula: see text] and [Formula: see text]. To end the decade-long discussion and to provide a novel type of infrared sensor, we are developing an uncooled μ-biomimetic infrared (IR) sensor inspired by Melanophila acuminata using MEMS technology. Here, we present the development of a μ-capacitor that is used to detect pressure changes and the characterization of the compensation mechanism. We describe the microtechnological fabrication process for air-filled capacitors with a ratio of diameter-to-electrode distance of 1000 and a technique to fill the sensor bubble-free with water. Finally, we estimate the sensitivity of the beetle using a theoretical model of the sensillum.