Given that the field of robotics and electronics are making inroads into the field of biology – in the form of biorobotics and bionics – it was only a matter of time before applications began moving in the other direction. For example, muscles have been considered in recent years as a potential replacement for electric actuators, in part because they can run in a nutrient-rich fluid without the need for any other power source.
The latest example of this biological-technological crossover comes from Illinios, where bio-robotics experts have demonstrated a bio-bot built from 3-D printed hydrogel and spinal muscle tissue that can “walk” in response to an electrical signal. Less than a centimeter in length, the “bio-bot” responds to electrical impulses that cause the muscle to contract.
According to study leader, Professor Rashid Bashir, biological tissue has several advantages over other robotic actuators:
[Muscle] is biodegradable, it can run in fluid with just some nutrients and hence doesn’t need external batteries and power sources – and it could eventually be controlled by neurons in our future work.
Previous versions, using heart muscle tissue, were also able to “walk” but were not controllable, as heart tissue contracts constantly of its own accord. Spinal muscle, by contrast, responds to external electrical stimuli and provide a range of a range of potential uses. These include bio-robots being able to operate inside the body in medical applications, or being used outdoors in environmental services.
And though this design is very simple, it serves as a proof of concept that demonstrates that the technology works. Bashir and his team are now looking to start extending toward more complex machines – incorporating neurons that can get the bot walking in different directions when faced with different stimuli. Initially, they’ll look at designing a more complex hydrogel backbone that gives the robot the ability to move in more than one direction.
They’re also looking at integrating neurons to steer the tiny bots around, either using light or chemical gradients as a trigger. This would be a key step toward being able to design bots for a specific purpose. As Bashir said:
The idea of doing forward engineering with these cell-based structures is very exciting. Our goal is for these devices to be used as autonomous sensors. We want it to sense a specific chemical and move towards it, then release agents to neutralize the toxin, for example. Being in control of the actuation is a big step forward toward that goal.
This development is significant for a number of reasons. Not only is it a step on the road towards bionics and biorobotics, it also demonstrates that the merging of technology and biology works both ways. Not only are machines being designed to improve our biology, our biology is also inspiring machinery, and even being used for its unique and superior properties to make machines run better as well.
And be sure to watch this video of the muscle-powered bio-robot being explained: