### Biohybrid Robots Fueled by Fungi: The Horizon of Adaptive Machines
In the realm of robotics, living entities frequently surpass machines in adaptability, environmental perception, and resilience. Although machines are superior in precision and speed, they often find it challenging to navigate intricate, dynamic surroundings as efficiently as biological systems. To address this disparity, researchers are delving into biohybrid robots—entities that incorporate biological parts like animal muscles, bacteria, or plants. Yet, these biological constituents come with unique obstacles, including limited lifespans and challenges in their maintenance within mechanical constructs.
In an innovative study, a group of scientists at Cornell University has embarked on an unconventional method by utilizing fungi—specifically, oyster mushrooms—to command robots. This groundbreaking combination of biology and technology holds promise for creating more adaptive, environmentally responsive machines, with possible applications in agriculture, environmental surveillance, and more.
### Why Choose Fungi?
At first glance, the concept of employing mushrooms to direct robots may seem like a narrative from a science fiction tale, echoing the fungal networks in *The Last of Us*. Nevertheless, fungi manifest numerous benefits that render them suitable for biohybrid applications.
Fungi exhibit remarkable resilience and can flourish in extreme conditions, ranging from the icy expanses of the Arctic to regions tainted by nuclear waste. They are also relatively simple to cultivate en masse, positioning them as a cost-efficient choice for biohybrid integrations. Furthermore, fungi are highly responsive to environmental factors, such as light and chemicals, making them prime candidates for detecting and reacting to changes in their settings.
### Grasping Mushroom Signals
The secret to employing fungi in robotics resides in their mycelium—the sprawling, thread-like structures that form the majority of a fungal organism. Mycelium networks not only facilitate nutrient uptake but also enable communication within the fungal community. Fungi employ electrical signals to sense and react to their surroundings, akin to how neurons relay information within animal brains.
The hurdle for the Cornell researchers was establishing a link between these fungal electrical signals and robotic systems. Past efforts to connect fungi to machines involved mapping their growth patterns, which failed to deliver real-time responsiveness. A significant breakthrough occurred when the scientists successfully cultivated mycelium within a 3D-printed scaffold, allowing it to develop into electrodes over a span of 14 to 33 days. This direct linkage enabled the team to capture and analyze the electrical activity of the fungi.
### Interpreting Fungal Communication
Following the integration of mycelium with the electrodes, the subsequent phase was to decipher the electrical signals. The team documented the electrical activity of the mushrooms over a month and eliminated any noise below 5 microvolts. By scrutinizing the resultant signals, they identified distinct electrical patterns corresponding to various stimuli, including exposure to ultraviolet (UV) light.
To evaluate the setup, the researchers equipped the fungal-electrode scaffolds in two robot designs: a starfish-like walking robot and a four-wheeled rover. The fungi-driven robots were capable of moving towards or away from a UV light source, confirming that the mushrooms could indeed govern the machines.
While this preliminary experiment indicated that fungi could carry out basic tasks like light detection, the true promise of fungal biohybrid robots lies in their capacity to sense chemicals. Fungi possess exceptional sensitivity to chemical fluctuations in their environment, far exceeding the performance of synthetic sensors.
### Fungi as Chemical Sensors
One of the most thrilling prospects for fungal biohybrid robots is their potential role as chemical sensors. Fungi can detect minute concentrations of chemicals in their surroundings, positioning them as excellent assets for applications like environmental monitoring or agricultural management.
“The obvious next step, once we have this more controlled system, is to examine chemical exposures and biological inputs,” notes Robert F. Shepherd, an associate professor of mechanical engineering at Cornell and co-author of the study. “Living organisms can amplify these signals far more effectively than synthetic systems when detecting very, very trace amounts of chemicals.”
However, the challenge remains in interpreting the signals emitted by fungi in response to various chemical stimuli. To tackle this, the team intends to gather extensive datasets of fungal electrical activity in reaction to different chemicals, including variations in soil acidity or the detection of harmful substances like cyanide. These datasets could then be utilized to train artificial intelligence (AI) models to decipher the fungal signals, potentially enabling the robots to recognize particular environmental conditions.
### Prospects in Agriculture and Beyond
Among the most promising uses for fungal biohybrid robots is in the agricultural sector. Fungi display acute sensitivity to environmental elements that impact plant well-being, such as soil acidity and nutrient concentrations. By embedding fungal sensors into robotic frameworks, farmers could acquire real-time feedback on crop health, facilitating optimized fertilization and irrigation strategies.
“We envision such systems as connection points, assessing plant health to prevent excessive fertilization of fields,” Shepherd elaborates. “Envision a quadruped robot with its feet embedded
