One part soft rubber body, one part rat heart cells, and a sprinkle of gold; these are the constituent parts for a new ‘biohybrid’ laser-guided robotic ray, being touted as the world's first 'artificial animal'. Demonstrations at Harvard University showed that it was capable of navigating an obstacle course fifteen times its length, guided by a blue laser light.
The ‘tissue-engineered, soft robotic ray’ was developed by an interdisciplinary team of researchers led by Kit Kevin Parker. The team first 3D-printed a soft elastomer body in two parts, sandwiching a middle layer of gold that resembles a skeleton. On top of these layers were grown rat heart cells, genetically engineered to respond to light. When a light is shone on the ray, the muscular circuity allows the body to contract in a wave from front to back, resulting in an undulatory motion that propels the ray forward. Some of the energy produced when the cells pull down is stored in the gold skeleton, and then released when the muscles relax, pulling the fins up again. Shining more light on one side makes the cells on that side contract more than the other, providing a steering mechanism – just as how the stingray moves in the natural world.
The functionality of the robo-ray is thus not only thanks to technological advances - such as 3-D printing and genetic engineering - but also to a way of approaching engineering problems known as ‘biomimicry’. This field of design seeks to draw inspiration from nature to solve design problems. In the case of the robotic-ray, bioengineering techniques were paired with a design that emulated the movement of a stingray, with astounding results.
Parker hopes that being able to replicate the movement of a stingray might hold the key to eventually producing an artificial human heart. This could be of huge medical benefit, as it could bypass the hurdle of needing to find a donor. Nevertheless, the line between therapy and enhancement is easily blurred: artificial hearts would presumably be less prone to aging than their naturally-endowed counterparts. The prospect of human enhancement has an intoxicating appeal, however it is important to bear in mind the potential for these developments to exacerbate existing inequalities.
The project crosses several disciplinary boundaries. As Parker tells Popular Science, "The cardiac biologist sees the implications for how the heart's built; the marine biologist sees the implications for how the stingray moves; and the robotics engineer sees the way you can use cells as a building material.” Although it’s not the first time that researchers have created a ‘bio-bot’, it is the most sophisticated iteration.
As far as immediate applications go, it’s possible that these creatures could be employed in ‘swarms’ for problem solving, for instance to search for a ‘black box’ lost underwater. A team at Case Western Reserve University just completed a similar project with this intention. Using organic robots for this kind of task, would mean that if they were lost then they would simply biodegrade or be eaten, minimising harm to the environment. Moreover, the stingray’s method of propulsion uses very little energy, allowing for the robots to have greater range with less constraints as regards to a source of energy.
At present, robots tend to be clunky and awkward, and even if we fashion them in our likeness we can instinctively tell that they are not human. Being able to deftly fuse the artificial with the organic could have significant implications for the future of robotics, enabling the production of ‘hybrids’ that have organic exteriors and could perhaps be indistinguishable from their natural counterparts (See image here). This research could have a profound impact on our conception of what it means to say that something is ‘living’.
Are such biohybrids organic or artificial? Animal or machine? Both? Let us know what you think in the comments.