Now, a new ability can be added to the list – controlling robotic exoskeletons. Developed by researchers at Cornell University in New York state, a pair of new robots are controlled by fungal mycelia, the part of the organism that grows underground.
By harnessing mycelia’s innate electrical signals, the researchers discovered a new control method that could allow the ‘biohybrid’ robots to react to their environment better than their purely synthetic counterparts.
“This paper is the first of many that will use the fungal kingdom to provide environmental sensing and command signals to robots to improve their levels of autonomy,” said senior author Rob Shepherd.
According to the internet, the innovation could be the start of a thriving new inter-species collaboration – or the start of a runaway robotic fungus apocalypse that could spell the end for civilisation.
Living systems
The Cornell team built two biohybrid devices – a soft robot shaped like a spider, and a wheeled robot. “By growing mycelium into the electronics of a robot, we were able to allow the biohybrid machine to sense and respond to the environment,” said Shepherd.
“In this case we used light as the input, but in the future it will be chemical. The potential for future robots could be to sense soil chemistry in row crops and decide when to add more fertiliser, for example, perhaps mitigating downstream effects of agriculture like harmful algal blooms.”
Synthetic sensors generally just have one purpose, said lead author Anand Mishra. Living systems, on the other hand, can respond to touch, light, heat, and other signals.
“If you wanted to build future robots, how can they work in an unexpected environment?” Mishra asked. “We can leverage these living systems… any unknown input comes in, the robot will respond to that.”
Some previous biohybrid robots have been powered by animal or plant cells, which are often sensitive to environmental factors and have short lifespans. Fungi, however, can be easily cultured and are “robust in extreme conditions” according to the Science Robotics paper on the work. They can also sense chemical and biological signals and respond to multiple inputs.
Integrating mushrooms and robots required more than just tech savvy and a green thumb. The project involved mechanical engineering, electronics, mycology, neurobiology and some signal processing.
The robots use the electrophysiological activity of the mycelia to control their artificial actuators. The systems consist of an electrical interface that blocks out vibration and electromagnetic interference and accurately records and processes the mycelia’s electrophysiological activity in real time, and a controller inspired by central pattern generators – a kind of neural circuit.
Essentially, the system reads the raw electrical signal, processes it to identify the mycelia’s rhythmic spikes, then converts that information into a digital control signal, which is sent to the robot’s actuators.
The biohybrid devices completed three experiments. In the first, the robots walked and rolled, respectively, as a response to the natural continuous spikes in the mycelia’s signal.
The researchers then stimulated the robots with ultraviolet light, which caused them to change their gaits, “demonstrating mycelia’s ability to react to their environment”. In the third scenario, the team was able to override the mycelia’s native signal entirely.
Mushroom machines
The implications of the work go far beyond the fields of robotics and fungi, the Cornell announcement said. “This kind of project is not just about controlling a robot,” said Mishra. “It is also about creating a true connection with the living system. Because once you hear the signal, you also understand what’s going on. Maybe that signal is coming from some kind of stresses. So you’re seeing the physical response.”
Fears voiced on social media of a robot-powered fungal takeover are premature, however – although videos show the spider-like bot scurrying across a table, a National Geographic clip shows that it has been sped up by a factor of 10. It seems like it might be a while before the mushroom machines will outpace humans.
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