by futurist Kit Arrow
Two hundred years ago, a significant injury to an extremity meant you would lose it, and have to deal with a rudimentary prosthetic like a peg-leg or hook hand. Fifty years ago, the same injury might not cost you the limb, but if it did, you at least had the option of a prosthetic that gave back some functionality, and was designed with comfort in mind. Twenty years ago, the first prosthetic controlled by a microprocessor was developed, the Intelligent Prosthesis knee, and helped people walk with a more normal gait. Today, we have a wide variety of prostheses, ranging in price from tens or hundreds of thousands for the absolute top-of-the-line models with microprocessors, programmed movements and even neural interfaces, to fifty dollar models made with 3-D printers that can be assembled by almost anyone in under three hours.
In this blog post and the next, I plan on exploring where we are now, and providing insights not only to where we will be twenty years from now, but how it will affect even those of us who don’t need replacement limbs.
Better than human
Oscar Pistorius is a remarkable man. I’m not endorsing his recent actions, but he will be remembered for his run in the 2012 Olympic games, becoming the first amputee to not only run in the Olympics, but to qualify for the semi-finals. Keep in mind he’s been a double amputee since before he was a year old, so he probably never walked without mechanical assistance. But just as remarkable as his determination to participate in his sport with full-limbed competitors is the technology that enabled him to run.
In the lead-in to the 2012 Olympics, there was significant controversy as to whether or not to allow him to compete, because his running blades might have given him an unfair advantage. That was the moment when prosthesis were first seen as having surpassed human limits, that they allowed a person to perform at a higher level than a normally-formed human. At the Olympics, the controversy around the blades was shut down, and while Pistorius performed well, he didn’t win. In the process, though, he still showed that a man without legs below the knee could compete at an Olympic level, better than all but a tiny fraction of humanity. Clearly, he’s a world-class athlete with or without the blades, and that’s a remarkable achievement in technology.
Running blades, for all the science involved, are essentially simple tools. Impeccably well designed, but still, all they do is propel someone faster. For an example of something more sophisticated, let’s look to Claudia Mitchell. Claudia Mitchell lost her left arm in a motorcycle accident, and has volunteered with the Rehabilitation Institute of Chicago (RIC) to be the first woman, and the fourth person, to have a neural interface with a bionic arm. The arm has been wired to nerves in her chest that once were attached to her missing limb, and she can control the hand and arm much like a real one. There is a learning curve, and she misses her sense of touch, but this is still an amazing leap.
Like Luke Skywalker
The arms produced by RIC are amazing, but not the best in the world. At least, not according to DARPA, who is funding several such projects. That award goes to the Luke arm created by DEKA in New Hampshire, led by Dean Kamen. Named after Luke Skywalker from Star Wars, who had his hand chopped off, the Luke arm not only has an electromyogram (EMG) electrode interface. This interface picks up nerve impulses from the upper arm and chest, as well as providing feedback from force sensors to control grip. But DEKA decided that wasn’t enough, so they also included toe switches in the users’ shoes that wirelessly transmit signals to the prosthesis, allowing for control of multiple joints simultaneously. This bionic arm passed FDA approval in May, and is currently the most sophisticated prosthetic in the world.
The Luke arm may be the most sophisticated bionic, but it doesn’t have the most sophisticated interface. That honor goes to Hector, the robot arm wired into the brain of Jan Scheuermann, a woman with spinocerebellar degeneration, a disease that has left her paralyzed below the neck for the past decade. Hector, her robot arm, is wired via a pair of tiny 96-pin electrodes into the part of her motor cortex that controlled her right arm. It took her three months to learn how to use the arm, but now she is capable of feeding herself, and can use the arm reflexively. Unfortunately, the arm lacks force feedback, so she doesn’t know how hard she is gripping something, and it requires a bulky set-up that can’t be removed from the lab at the University of Pittsburg Medical Center.
If you’re looking for something still reasonably high-tech that doesn’t require a massive support infrastructure, then i-Limb might be the choice for you. These bionic hands sync to your smartphone, and have 24 programmable grips and gestures available through their app. Unlike the preceding two arms, they are readily available commercially, and apparently easy to use and set up. They’re not cheap, but are easier to obtain than getting into a DARPA test program, which is where the preceding limbs were invented.
But if you don’t have the $40,000 starting price for an I-Limb, there’s still hope. Project Daniel is a maker-community group based in south Sudan, where local people are trained to make simple prosthetic limbs from 3-D printers for less than $50. The plans are available online, so all you need is access to a 3-D printer, and you can build your own in about three hours (not including print time). This came about because of one young man in Sudan, called Daniel, who had both arms blown off during the war there. Local press grabbed his story, and it came to the attention of the creative geniuses at Not Impossible Labs (“Technology for the sake of humanity.”) They crowdsourced the problem of not only how to give this young man a prosthetic arm, but how to supply them for the entire region. And once the design was completed, Mick Ebeling of Not Impossible made the trip to Sudan to set up what is believed to be the world’s first 3-D printing prosthetic lab and training facility. Sometimes the future is about bringing better quality of life to people far away rather than shiny, new objects right here.
The last bionic that I’ll mention for now is neither a limb nor an implant. It’s an exoframe, which is a powered frame that helps people to walk. Unlike the exoframe used by Ripley in the movie Aliens, this frame doesn’t lift heavy loads, or fight vicious xenomorphs. In our world an exoframe allows people with lower-body paralysis to walk. Such a powered frame attaches to the body with Velcro straps, and the user’s arms hold onto a pair of crutches, while the battery is on the back, supported by the device itself. As a replacement for a wheelchair, it’s incredibly innovative and freeing, but there are issues that are holding back its development. First, with a price tag of $130,000, potential users have to convince insurance agencies that it’s a medical necessity, or else it will be restricted to the 1% that can afford it. Secondly, many people in wheelchairs distain it for the slow speed, particularly in a time where wheelchair ramps and accessibility are at an all-time high. Lastly, it’s bulky and noticeable. All of this fades into the background for the testers, who are elated to be able to stand and walk again. EKSO, the company behind the frame, are aiming to slim it down enough so that you could sit in a business class airline seat while wearing it.
By the year 2034…
These technologies are amazing, but where will they be in twenty years? Let’s start by looking at the obvious. Battery technology is improving with amazing speed, owing to the billions being invested in it. There is a serious push across several industries to get better batteries, not only longer lasting, but faster charging, smaller, and cooler. This will allow better life and smaller power sources for all prosthetic devices (save ones like Project Daniel, which are non-powered). Secondly, we have a better understanding of how the body and limbs work now, so we can build and engineer limbs that interface better with our bodies, and work under the control of our minds. And computing power is also increasing, giving us more, and more flexible, options to integrate into limbs. Instead of 24 grips and gestures available with today’s i-Limb, we’ll have 240, or 24,000, or whatever number we want.
Prosthetic arms in 2034 will be fully integrated. The site of the injury will have a cap on the end, the flesh side connecting to nerves and keeping the muscles there healthy, while the other side will interface directly with the bionic prosthesis. The arm will attach to and cover the cap, sticking to the limb with a combination of suction and non-irritating electrical adhesive, and will be be turned off when removed. The limb itself will have a more powerful computer than either the one I am writing this on, or the one you are reading this with, and probably more powerful than anything currently in existence, which will add enormous power and flexibility. It will be able to accurately interpret the signals from the biological nerves in the arm through the cap, and translate them into accurate, natural movements. The arm will be as articulated as a flesh and blood arm, with silent servos moving the elbow, wrist and finger joints.
It seems likely that the movement of a standard arm (not including unusual characteristics such as being double jointed) will be extensively mapped and catalogued in future, and have been fed into the processor in tomorrow’s bionic arm. The covering of this future model might be lime green, or changeable with the touch of a button, and able to upload different patterns, but also come with a completely realistic covering, down to freckles, arm hair and warmth. While full feeling will (probably) still be impossible, tiny electrodes embedded in the fingertips may provide perhaps 80% of normal sensation, and optional programming may allow the arm to feel an itch at random intervals in order to make it feel more life-like. About the only thing that arm won’t be able to do is heavy lifting, and that’s more a matter of the limitations in the socket, rather than the arm itself. For lifting anything greater than 15 kg, or about 30 lbs, a shoulder strap would have to be attached so the socket doesn’t come loose.
Exoframes will no longer be used just for mobility enhancement, but for heavy labor as well. People with spinal injuries that can’t be regenerated will have a cybernetic bypass installed, connecting the severed or damaged nerves to the healthy part of the spine. It will take a few months of physiotherapy to get used to, but it may allow perfectly natural movement, perhaps even up to professional-level dancing.
In fact, the best thing about future bionics may be that they will only be noticeable if you want them to be. Many people will never know which, if any, of their friends or co-workers have bionic arms or legs, so natural and smooth will their movements be. They will be unremarkable, in cost, ability, or public attention.
But nice though this is for these in need of prosthesis, will it really make any difference to the vast majority of the population who aren’t paralyzed, or aren’t missing any limbs? I’ll take that up in my next blog.
© Copyright, IF Research, September 2014.