Monday, August 17, 2009

SMORGASBORG #5: Exoskeletons part D

considering the devastating nature of brain and nerve injury, it is no surprise that people are very excited about research in the areas of biomechatronics, robotics, and other areas exploring ways to support and/or rehabilitate people with weakened or paralyzed bodies(1). Here are some examples of exoskeletal technology put to better purpose than superhuman strength and killing people. According to my constructed definition of a cyborg in SMORGASBORG #1, these thing wouldn't qualify one to be a cyborg because they lack an information exchange between the machinery and the body wearing it. But what the heck...

There's a video ad of the suit at this link, but a better version is on YouTube.

A company called Argo Medical Technologies is developing an exoskeletal system for the legs. The exoskeleton, called ReWalk, doesn't provide an exchange of information between it and the wearer. You have to cue actions individually. The suit doesn't know if you want to go up one stair, or five(2). But who cares? It's so cool! There's a control panel that you can strap to your wrist. You cue ReWalk by pushing a command button that says something like "stand up." Then you cue the suit that you're ready to stand by tipping yourself forward, and the suit stands you up. Crutches have to be used to help maintain balance. It looks a little cumbersome, but trying to get a wheel chair up even one step can be really hard.

(If I have to listen to one more Western newscaster say
"Domo arigato, Mr. Roboto" one more time - I'm going to SCREAM!)

Above is a link to a video about a Japanese company called Cyberdyne! Argh! Can you believe it? They have been doing research, and have now started marketing a robotic suit called HAL. Argh! Can you believe it? I assume this isn't a hoax. If it is, I suspect the technology is very nearly there for this kind of thing. These suits(3) interpret nerve impulses that are trying to stimulate muscular contraction. The suit will then move the wearer's limb the way the person is trying to move it. It can give extra-human strength to a normal person, or produce normal strength for a weakened individual. It essentially anticipates and performs the movements of the wearer. In the video, they show elderly people who have suffered strokes using a half suit, and care-givers using the full body suit to carry a patient.

The full body suit's structure will hold your joints in alignment to prevent injury from forces they can't handle. The half suit doesn't seem to offer much support around the pelvis, so it might be uncomfortable if you don't have the strength to hold yourself erect for any period of time. That would limit who could use it and how it could be used.

Exoskeletal devices such as these would help someone confined to a wheelchair feel more normal and independent. Stairs could be negotiable without a ramp. You wouldn't always have to be looking up at people as they stood over you. For many people with flaccid paralysis or paresis, these types of devices wouldn't be a cure, but would provide a form of exercise(4) and potentially improve posture, which would improve health.

Luke and Yoda

The kid is using his hand for show. The sensors go on your head.

Here is a trivial step on the road to great things. A toy called The Force Trainer teaches you to control a fan with your mind. Yes... a fan... yes... your mind. The fan in turn blows a ping-pong ball into the air, in a clear plastic tube, to levitate it. I can't decide if this toy is cool, or lame. Eventually, I assume that people with spinal cord injury may be able to use a brain wave sensing device that either helps them move their body, or control a robot that can more things for them, which sounds more interesting.

"What is it like to mentally float an object and then hurl it far into the distance? The Adventures of NeuroBoy fulfills this classic dream by demonstrating the experience of superpowers." You can also blow things up. You wear a headset and manipulate an animated game with your mind. I'm sure it's not nearly as disappointing as it looks online.

Look at this! A "bionic hand controlled by a patient's mind and muscles." It's expensive, but probably worth it.

Enough with exoskeletons. Next time we will look at some of the factors involved in implanting devices into living tissue. It turns out that building an army of human killing cybernetic organisms is trickier than you'd think.

1. Some new devices may be able to "retrain" someone's nervous system. Some devices will not help with recovery from injury, but will facilitate more physical independence. It all depends on what caused a person's paralysis in the first place.
2. Oh! I can see the madcap Adam Sandler comedy already!
3. HAL is a lower body model. They will have a full body model out soon.
4. "Exercise" is a relative term meaning any activity that will physically challenge a particular body.

Monday, August 10, 2009

SMORGASBORG #4: Exoskeletons part C

Only a moment? Yes, that's it. Otherwise I'll go on and on about Stephen Sommers and how much I love The Mummy and Van Helsing. (I know three people who are going to stop visiting this blog after reading that sentence, but there it is: I love Sommers for his mind.)

And what a mind! That guy never fails to put at least two kinesthetically satisfying action sequences in his films. Watching GI Joe as a choreographer, I respond to the way the action is timed, plotted, and filmed. As a pathology teacher, and as someone who watches a doctor on TV, I can appreciate the way the Parisian chase scene would be physically impossible to survive, even with those exoskeletal suits the Joes were wearing. Does this ruin my enjoyment of the film? Absolutely not! I don't watch Stephen Sommers films for their realism.

The exoskeletal suits

Why couldn't the Joes endure an action-packed high speed romp through Paris in those suits? Well, I'm going to put this as specifically as possible while trying to stay sensitive to readers who want to enjoy this very enjoyable sequence in theaters near them. Those exoskeletal suits encase one head to toe, are reinforced everywhere, give the wearer supplemental visual interface with their environment, and enhance physical speed, power, and coordination. Plus they have guns build into the sleeves! The wearer of such a suit is one kick-ass cyborgian lobster.

But no matter how tough the suit is, the contents of the suit (meaning the person inside) are comparatively delicate. Even though a skull is pretty tough, the brain inside it is liquidy and fragile. It can slosh. When it does, the connective tissue holding your brain and its blood vessels in place can tear. That causes intracranial bleeding and injury. It's kind of like having a stroke. This type of injury is called a contrecoup injury.(1) Perfectly named if aquired during a ballistic Parisian chase scene.

Guess where that head is going

How do you slosh your brain? Get your body flying around the streets of Paris at the speed of traffic, and then stop suddenly. If you don't have access to an exoskeletal suit, get in a car and put on your seatbelt, or get on a motorcycle and put on your helmet. Kick up some speed, and drive right into a brick wall. It works practically every time(2).

Okay, I got sidetracked. Next time we'll do practical applications of the suit for paralysis.

1. Remember Terminator Salvation: Spoiler Alert #2? I also write about contrecoup there, if your curious.
2. Coup and contrecoup injuries can happen from a blow to the head, or through sudden deceleration. Either way, compressive forces act on one side of the brain, while shearing forces act on the other. Sometimes these injuries can be mild, but they can also cause coma, or death. For an excellent resource about traumatic brain injury, visit

Friday, August 7, 2009

SMORGASBORG #3: Exoskeletons part B

Biomechatronic(1) feedback and motor systems could be used for prosthetic devices that replace limbs, or for exoskeletal structures that support and enhance function of an intact body.

External devices that interface intimately with human internal anatomy are represented in RoboCop, as Murphy's (Peter Weller) shattered corpse is resuscitated, amputated, and implanted into an exoskeleton that also serves as a prosthetic(2). The bullets from the men who murder him, and the surgeries of the people who "save" him, leave Murphy very little that can be physically recognized as the man he was. Once he is implanted within his carapace, and once additional devices are implanted within what's left of his body, he becomes even less recognizable as a man. Murphy is deliberately brainwashed in this cyborging process. He is rendered less than human by the people who re-make him. This movie is an engrossing investigation of our corporeal attachment to human identity(3). It's also a kick-ass action film.

Del Spooner (Will Smith) defending himself against an evil robot.

In I, Robot, Del Spooner has lost his arm as the result of a car accident. The arm has been replaced by a prosthetic. To Spooner's mind it is a robotic prosthetic, and Spooner hates robots. Although Isaac Asimov is light years away from this film, the amputee who hates his life-like robotic prosthetic (and himself, by extension) makes for good drama, I guess.

But in this film, Spooner remains a human and a man. Although he is conflicted about his acceptance of a prosthetic arm, he is unquestioningly human to all who know and see him. He retains his personality. He works out. He is a guy with a motorcyle. Unlike RoboCop, he is sexually attractive and has his 'nads(4).

Spooner's prosthetic upper extremity includes all of his shoulder and a number of ribs. This type of device probably has a surgically implanted interface, since there would have to be a design element that allowed the prosthetic rib replacement to maintain a vacuum between the lung and chest wall. I bet the prosthetic ribs even act and react to Del's rib movement and breath rate. This would require some kind of invasive interface with the nervous system. To support my logic, we see that the inside of the fake arm is all lit up and sparkly. It just screams fancy technology capable of anything. I rest my case.

Discussion of biomechatronics and the developments in prosthetics and exoskeletons brings us to what they could (and probably should) be used for, beyond killing and superhuman strength, I mean. What is that use? To restore normal function to a body that is missing a part, or that has been weakened, paralyzed, or otherwise damaged.

Some bodies are intact but unable to respond voluntarily to the will of the brain. This is the result of damage to the nervous system. Damage from injury or disease can happen in a number of different ways, and cause a variety of symptoms. Insult to a nerve may cause a complete flaccid paralysis(5) or a partial paralysis(6) to the part of the body the nerve served. Injury to the spinal cord can lead to paralysis or paresis of one or more limbs.

"Wrist drop" a.k.a. radial nerve palsy.
This painter suffered lead poisoning and lost the use of the muscles that extend the wrist.

Damage to the brain can lead to spasticity, rigidity, tremors(7) etc., anywhere in the body, depending on what part of the brain is damaged. A person with any of these conditions may have partial control over the limb, or no control at all. It depends on the extent of the damage to the nervous system.

A really funny comedian (with cerebral palsy).

What could damage, alter, traumatize, or injure the nervous system? Direct trauma(8), poisoning(9), or diseases(10) are the usual culprits.

Imagine, if you can, what it would be like to never stand up again. Imagine how your day would change if you could use your shoulder and elbow, but not use your hand, or what would it be like to walk with a foot that doesn't respond. Think about how your body would change if you could no longer contract muscles in your arms or legs. If a muscle stops contracting it shrinks (atrophies), just as it will grow in size if you exercise it. How would you feel about your physical appearance if your limbs were atrophied and much smaller than those of a more physically active person?(11)

This young man in New Delhi contracted polio myelitus.
Polio is caused by a virus that attacks motor nerves, leading to flaccid paralysis.

As a massage therapist, I have thought about these questions a lot. When you are touching a disabled body, and you develop a relationship with the body and the person, it forces you to think really hard. I have an intellectual understanding of the causes of many of these conditions, and the basics of various therapies one can undergo to recover from nerve and/or brain damage. I can appreciate the heroic efforts of my patients, even when they are at their pissy worst. But frankly, that knowledge doesn't help much. I know I've been lucky so far, and that my luck could change. I don't know how I would react to being struck by any disease or debilitating injury, until it happens.

As you would expect, my massage patients have all viewed their conditions differently. From observation, I have concluded that descriptive terms like "the worst thing imaginable," "pain in the ass," and "extremely frustrating," don't begin to describe the impact of losing physical function has on someone's life.

Yes, we are ending on a downer. Next time, exoskeleton technology applications for persons with paralysis.

1. See SMORGASBORG #2 for more on biomechatronics.
2. What is a prosthetic? An artificial substitute or replacement for a part of the body (eye, leg, breast, tooth) or a replacement for a joint (hip, knee). A prosthesis can be used for functional or cosmetic purposes, or both. You can go to for a more in depth definition.
3. Sorry for that last sentence, folks! I'm reading too much academic writing and it's causing me to "act out."
4. We assume Spooner's testicles and penis weren't harmed in the accident. With Murphy in RoboCop, the corporation orders the amputation of his viable leg. Through that act, it is implied that any other unneeded parts are also removed. He doesn't eat normal food. Digestion and excretion have been altered to fit his new being. Murphy wouldn't need a functional reproductive system, either.
5. Paralysis where there is a loss of tone, loss of reflexes, and atrophy (shrinkage) and degeneration of affected muscles.
6. Partial paralysis is called paresis. Partial flaccid paralysis may manifest as weakness in the body part.
7. Spasticity and rigidity are produced by excessive uncontrolled muscular contraction and are due to brain (as opposed to nerve or spinal cord) injury. Tremors can have a variety of causes, and like spasticity and rigidity, cannot be willed to stop.
8. Car accident, birth trauma, gunshot, stabbing, etc.
9. Lead, mercury, etc.
10. Multiple sclerosis, amyotrophic lateral sclerosis (ALS or Lou Gherig's disease), Parkinson's etc.
11. I teach lessons on massage for different deformities, and I'm used to using clinically descriptive language to describe these conditions. Terms like "valgus" or varus", etc. If I'm massaging a patient with a deformity, we're talking about their body, the state of the tissues, anatomical structures, goals for the session, etc. Or we're talking about movies, our pets, or food. I'm not current on the acceptable social language used to describe atrophy or other conditions. I'm not even sure that there are socially acceptable non-clinical adjectives out there. Any comments?