When most people hear the term “robot,” they picture a mass of lumbering metal powered by batteries, motors, electrical wires, and circuit boards. However, recent advancements have forced me to rethink my own definition of a field I’ve been dabbling in for over a decade.
If we broaden our understanding and try to apply it to other systems, we find some very interesting implications, particularly in the realm of biology. Biological entities are no strangers to the concept of closed loop control systems: a clustering of things that work together in a feedback loop to regulate the behaviour of a system. Just look at how well the human body regulates its own temperature, blood chemistry, hydration, and motion. However, what happens when aspects of our feedback loop break down?
When it comes to motion, this is a problem we know all too well in cases of paraplegia, quadriplegia, and other neuromuscular disorders. These conditions are typically caused by a severing or degradation of the signal between our controller (the brain) and our actuators (the muscles). We are in essence admitting defeat to the problem of a snipped wire. While teams around the world are attempting to solve these problems through the application of exoskeletons (don’t get me wrong, this is awesome), why should we neglect the still functional motors we have inside of our limbs?
I realize that the problem of replicating the human nervous system is far more complicated than I’m letting on, however, I urge you to let your mind drift into the future with me. Imagine if every time a paralysed individual wanted to move their legs, the neurological firing which would normally fall on dead synapses was picked up by a very sensitive device to measure the electrical signals in the nervous system. Using some sort of signal conditioner, we could interpret the intent of each of these signals (kick, step forward, stand, etc.). Then, using the principles of functional electrical stimulation (FES), we could generate artificial signals on the muscular side that would essentially shock muscles back to life in a coordinated manner to replicate the intent of motion. In the absence of simply soldering a few nerves back together, we’re creating a complicated bridge around the point of disconnect by using sensors, A/D converters, and electrical impulses to replicate signals.
As crazy as this sounds, there are already a handful of organizations dabbling in this field. Companies such as Bioness, Axio Bionics, and Odstock currently produce open-loop FES devices intended to activate muscles for the purpose of rehabilitation and simplistic closed loop devices to help augment cases of partial motion loss. These rudimentary closed loop systems often work where an individual still has some motion intact and, by detecting footfalls, they provide a small jolt of electricity to help with stability and speed.
Current limitations on systems for full paralysis as described previously are twofold. First, detecting and processing the signals in the body is extremely difficult because our nervous system does not operate like the electrical systems we are used to; it operates through a sort of bio-chemical electrical differential and it operates at extremely low amperage. Second, when applying stimulation to the muscles, output is not a simple case of on/off, but a perfect coordination of multiple muscles in a dynamic and adaptive way. In short, our control system would have to be exceptionally precise, near-real time, and massively robust.
However, assuming that we can overcome these challenges, the implications of this emerging technology reach far beyond aiding the disabled. If we want to let our minds truly wander into the realm of the unknown, consider the application of biological robotics when combined with artificially manufactured tissues and organs (think bio 3D printing). In many cases, biological systems are more efficient and powerful than mechanical ones and, if we could custom manufacture bio-motors and actuators to integrate into the products and systems we design, we could generate a whole new type of device. We could begin to build hybrid bio-mech devices that leverage the strength, precision, and durability of mechanical designs with the efficiency, responsiveness, and adaptability of biological systems.
Given that these “biobots” would be partially living organisms, we would of course need to power them in much the same way that we fuel our own bodies. Support systems that provide energy, oxygen, and other necessary chemical building blocks would be required, essentially to keep these tissues alive. Instead of oil and electricity, our biobots would need efficient methods for eating and breathing in order to sustain their function. While lacking sentience, we would have to begin to treat our gadgets, products, and industrial systems like pets; living organisms that need to be tended to and cared for.
Imagine your car being powered by some sort of artificial heart. Picture your home being heated and cooled by a set of modified, oversized lungs. Think about walking into an elevator that was being pulled 50 stories up by a massively elongated muscle fibre that expanded and contracted with perfect control to stop at each floor. Is the future of gears, circuits, magnets, and metal that we’ve been envisioning for years… wrong?
There are, of course, ethical considerations that arise with this alternate future. Even if these biological entities are artificially constructed, they will force us to question how we perceive and interact with life itself. Inevitably, we will eventually have to ask the question, “is this playing God?”
Yeah… a little bit. But we all knew it was bound to happen.
Photo: “Hooked Into Machine” by Shan Sheehan