Living Fungal Sensor

Article

arxiv.org

A fungal skin is a thin flexible sheet of a living homogeneous mycelium made by a filamentous fungus. The skin could be used in future living architectures of adaptive buildings and as a sensing living skin for soft self-growing/adaptive robots. In experimental laboratory studies we demonstrate that the fungal skin is capable for recognising mechanical and optical stimulation. The skin reacts differently to loading of a weight, removal of the weight, and switching illumination on and off. These are the first experimental evidences that fungal materials can be used not only as mechanical `skeletons' in architecture and robotics but also as intelligent skins capable for recognition of external stimuli and sensorial fusion.

Article

arxiv.org

Fungal mycelium, a living network of filamentous threads, thrives on lignocellulosic waste and exhibits rapid growth, hydrophobicity, and intrinsic regeneration, offering a potential means to create next-generation sustainable and functional composites. However, existing hybrid-living mycelium composites (myco-composites) are tremendously constrained by conventional mold-based manufacturing processes, which are only compatible with simple geometries and coarse biomass substrates that enable gas exchange. Here we introduce a class of structural myco-composites manufactured with a novel platform that harnesses high-resolution biocomposite additive manufacturing and robust mycelium colonization with indirect inoculation. We leverage principles of hierarchical composite design and selective nutritional provision to create a robust myco-composite that is scalable, tunable, and compatible with complex geometries. To illustrate the versatility of this platform, we characterize the impact of mycelium colonization on mechanical and surface properties of the composite, finding that it yields the strongest mycelium composite reported to date, and demonstrate fabrication of unique foldable bio-welded containers and flexible mycelium textiles. This study bridges the gap between biocomposite and hybrid-living materials research, opening the door to advanced structural mycelium applications and demonstrating a novel platform for development of diverse hybrid-living materials.

Article

spiedigitallibrary.org

This work explores the sensing potential of mycelium with the intention of incorporating this as an intrinsic sensing mechanism within structural materials. Infrastructure plays a critical role in modern societies with regard to economic productivity, social cohesion, and community well-being. By merging materials that are used for construction, such as concrete with living components, we aim to add intrinsic monitoring mechanisms that could usher in a new era of structural monitoring solutions. Mycelium, the vegetative part of the fungi, has been shown to have an extracellular electrical potential that changes when exposed to various physical and chemical stimuli, making it an ideal candidate for this purpose. In this preliminary investigation, we analyse the electrical behaviour of mycelium exploring its potential use as a sensing material within infrastructure components.

Article

news.cornell.edu

Building a robot takes time, technical skill, the right materials – and sometimes, a little fungus. In creating a pair of new robots, Cornell researchers cultivated an unlikely component, one found not in the lab but on the forest floor: fungal mycelia. By harnessing mycelia’s innate electrical signals, the researchers discovered a new way of controlling “biohybrid” robots that can potentially react to their environment better than their purely synthetic counterparts.

Article

fungalbiolbiotech.biomedcentral.com

Mycelium-bound composites are potential alternatives to conventional materials for a variety of applications, including thermal and acoustic building panels and product packaging. If the reactions of live mycelium to environmental conditions and stimuli are taken into account, it is possible to create functioning fungal materials. Thus, active building components, sensory wearables, etc. might be created. This research describes the electrical sensitivity of fungus to changes in the moisture content of a mycelium-bound composite. Trains of electrical spikes initiate spontaneously in fresh mycelium-bound composites with a moisture content between 95% and 65%, and between 15% and 5% when partially dried. When the surfaces of mycelium-bound composites were partially or totally encased with an impermeable layer, increased electrical activity was observed. In fresh mycelium-bound composites, electrical spikes were seen both spontaneously and when induced by water droplets on the surface. Also explored is the link between electrical activity and electrode depth. Future designs of smart buildings, wearables, fungi-based sensors, and unconventional computer systems may benefit from fungi configurations and biofabrication flexibility.

Article

physicsworld.com

Fungal mycelium skins can be used as substrates for electronic devices, physicists and materials scientists in Austria have shown. The team used the thin skins to create autonomous sensing devices consisting of mycelium batteries, a humidity and proximity sensor, and a Bluetooth communication module. As well as providing a flexible surface for electrical circuits to be patterned on, the skins are biodegradable and could help cut electronic waste.

Article

pure.hud.ac.uk

Mycelium-bound composites are normally made of discrete lignocellulosic substrate elements bound together by filamentous fungal hyphae. They can be formed into bespoke components of desired geometries by moulding or extrusion. Mycelium-bound composites with live fungi have been shown to be electrically conductive with memfractive and capacitive attributes. They can be integrated into electrical circuits with nonlinear electrical properties. Advancing fungal electronics, we studied the AC conductive properties of mycelium-bound composites and fungal fruit bodies at higher frequencies across three overlapping bands; 20 Hz to 300 kHz, 10 Hz to 4 MHz and 50 kHz to 3 GHz. Measurements indicate that mycelium-bound composites typically act as low-pass filters with a mean cut-off frequency of ∼500 kHz; with ∼−14 dB/decade roll-off, and mean attenuation across the pass band of <1 dB. Fruiting bodies have between one or two orders of magnitude lower mean cut-off frequency (5 kHz–50 kHz depending on species); with −20 dB/decade to −30 dB/decade roll-off, and mean attenuation across the pass band of <3 dB. The mechanism for the frequency-dependent attenuation is uncertain; however, the high water content, which is electrically conductive due to dissolved ionisable solids is probably a key factor. The potential for mycelium-bound composites and fruiting bodies in analog computing is explored.

Article

arxiv.org

Mycelium, a natural and sustainable material, possesses unique electrical, mechanical, and biological properties that make it a promising candidate for biosensor applications. These properties include its ability to conduct electrical signals, respond to external stimuli such as humidity and mechanical stress, and grow integrally within structures to form a natural network. Such characteristics suggest its potential for integration into self-sensing systems to monitor vibrations, deformations, and environmental conditions in buildings and infrastructure. To understand the output voltage generated by these biomaterials in response to an applied electrical input, it is essential to characterize their spatial and temporal properties. This study introduces an electrical impedance network model to describe signal transmission through mycelium. In combination with the inhomogeneous wave correlation (IWC) method—commonly used in elastic wave propagation—we demonstrate, for the first time, the dispersion behavior of living mycelium both theoretically and experimentally. We reveal the frequency-dependent and spatial attenuation of electrical signals in living, dehydrated, and rehydrated mycelium, emphasizing the critical role of humidity in enabling effective signal sensing. Furthermore, dispersion analysis is used to assess the homogeneity of mycelium, underscoring its feasibility as a living, green sensing material. This research lays the groundwork for innovative applications of mycelium in sustainable structural health monitoring.

Article

arxiv.org

Living fungal mycelium networks are proven to have properties of memristors, capacitors and various sensors. To further progress our designs in fungal electronics we need to evaluate how electrical signals can be propagated through mycelium networks. We investigate the ability of mycelium-bound composites to convey electrical signals, thereby enabling the transmission of frequency-modulated information through mycelium networks. Mycelia were found to reliably transfer signals with a recoverable frequency comparable to the input, in the \SIrange{100}{10000} {\hertz} frequency range. Mycelial adaptive responses, such as tissue repair, may result in fragile connections, however. While the mean amplitude of output signals was not reproducible among replicate experiments exposed to the same input frequency, the variance across groups was highly consistent. Our work is supported by NARX modelling through which an approximate transfer function was derived. These findings advance the state of the art of using mycelium-bound composites in analogue electronics and unconventional computing.

Article

arxiv.org

Mycelium bound composites are promising materials for a diverse range of applications including wearables and building elements. Their functionality surpasses some of the capabilities of traditionally passive materials, such as synthetic fibres, reconstituted cellulose fibres and natural fibres. Thereby, creating novel propositions including augmented functionality (sensory) and aesthetic (personal fashion). Biomaterials can offer multiple modal sensing capability such as mechanical loading (compressive and tensile) and moisture content. To assess the sensing potential of fungal insoles we undertook laboratory experiments on electrical response of bespoke insoles made from capillary matting colonised with oyster fungi Pleurotus ostreatus to compressive stress which mimics human loading when standing and walking. We have shown changes in electrical activity with compressive loading. The results advance the development of intelligent sensing insoles which are a building block towards more generic reactive fungal wearables. Using FitzhHughNagumo model we numerically illustrated how excitation wave-fronts behave in a mycelium network colonising an insole and shown that it may be possible to discern pressure points from the mycelium electrical activity.

Article

popsci.com

Researchers created a biohybrid robot that uses electrical signals in mycelium to move around.

Article

jku.at

JKU researchers recently began using glossy paint fungus skin (Ganoderma lucidum) as a substrate for electronic components.

Article

popsci.com

The lead researcher says he is “planning to make a brain from mushrooms.”

Article

asme.org

For a fast growing, biodegradable substrate for electronics, researchers are turning to mushrooms.