I have seen the HAL Robotic Exoskeleton in a forum on cybernetics (the use of robots to enhance the human body). I was really impressed by how helpful it could be to people: imagine people who got polio at birth, and had never moved one of their leg, walking on two feet for the first time! That's just one of the extraordinary applications of these robot suits. And what's even better with this Japanese robot leg is that it is a medical robot. No military robots applications were intended, which contrasts a lot with the research made in America.
HAL stands for Human Assistive Limb, and was developed by Cyberdine Ltd., with researchers from Tsukuba University in Japan. While Cyberdine (from Terminator) and HAL (from Space Odyssey) sound like they plan to take over the Earth, their technology is one of the most helpful robotic application for humans.
The goal is to wear a robotic exoskeleton on you to support your weight and help you in your movements. The robot suit, as they call it in Cyberdine Ltd., has to feel your intention, and then not just follow your movement but actually do it for you.
So the first question is: how does it feel your intention? Before putting on the HAL robotic exoskeleton, you need to put some electrodes that sense your muscle activity. These patches are called EMGs (electromyography) that look a little like the patches used to stimulate your muscles for fitness, but this time it's your muscles that stimulate the patch. So you still need to be able to activate your muscles with a nerve impulse to make it work (it's an important detail when it comes to who can use the robotic suit, in the next part).
The second question is how does it make you move? Well, it is really like you were driving a robot by showing it which muscle it should move for you. A little muscle activity is enough to send a big torque in the motors, so that it multiplies your strength. The articulations of the robot suit contain motors while the skeleton is supporting the weight and "holding" your limbs to make them move comfortably.
That is actually the most interesting thing about this robot suit: it was conceived as a medical robot, not a military robot. American research focuses on robotic exoskeletons to make soldiers able to carry heavy loads on long distances, and still be fresh for fights afterward. But Japan has (almost) no army, and its problems are more focused on their aging society, and how to handle dependence of old or disabled people.
So how can the HAL suit help old or disabled people? Well, the first applications were to help people recover from partial spinal injury (when there are still some nerve connections) or strokes in rehabilitation clinics. Doctors have known for years that stimulating the muscles help the recovery. The problem is that when the patient is unable to move by himself, you need one or several assistants to stimulate manually the limbs. The HAL robotic Exoskeleton is a great machine to teach the patients in rehabilitation how to walk again. Studies have shown better and faster recovery for patients using the suit.
During a conference by the CEO of Cyberdine Ltd, Yoshiyuki Sankai, I could also see how a patient with a muscle atrophy in his right leg (the muscles in his right leg never developed because of polio) could use the robot. In less than one day of training, he was able to stand on both legs and walk for the first time in his life. Several other examples showed that the robotic exoskeleton could help people with various muscle disease that made them unable to use one or several limbs.
As I said before, it doesn't work if you don't have the nerve connections reaching your limbs. So in the case of a complete spinal injury, it will not be able to help. Still, this is a major advanced in reeducation medicine, and Cyberdine is working to improve it. They are working on a brain scanner helmet (see picture above the 2), the person on the right). The intent is to allow people to "drive" the robotic exoskeleton with their brain, and thus helping even more people.
Though only the leg system (for 1 or both legs) is being used in Japanese clinics, Cyberdine Ltd. created several versions of the robot suit. The common ones are able to support your own weight and help in your movements. They are already used in several rehabilitation clinics in Japan, usually covering one or both legs. But they can be as small as one articulation (one knee or one elbow), or cover the whole body. It comes in different sizes though, covering people from 1'45m to 1'75m, and up to 80kg.
The next model is the one that is used mostly for demonstration. It covers the body like a light armor and can carry some 70kg with one hand. But they wanted to make robot suits that would enable to carry humans (in hospitals and retirement homes, mainly). In Japan, a machine carrying a human should have a 4 fold security margin: to carry a 80kg human, you should actually be able to carry 240kg (elevators and cars should comply to this, for example). That's why Cyberdine Ltd. created the heavy robotic exoskeleton, that really looks like a mecha armor from a Japanese animation series (ever read "Red Eye"?). It was revealed during the Shanghai World Exposition 2010, where it carried around young ladies on one arm.
From there, Cyberdine has diversified and are creating the suit for the hand (only one finger seems ready though). They are also creating a humanoid robot using the HAL technology to learn how to walk, and have also shown some videos of bionic leg: a robotic leg that would replace a missing one from the knee (but they didn't elaborate on that).
As you see here, the HAL robotic exoskeleton is a technology that is focusing on helping people, and can achieve near miracles when it comes to make disabled people walk again or for the first time. The sad news is that after Japan, only Germany has started the process leading to the use of the robot suit, and this process make take 1 or 2 years! So it's not ready to enter your home just yet. Be patient, and I hope this kind of technology can give hope to people who would need it to walk.
Other pages that may interest you:
Japanese robots are awesome. Discover more of them: the funny ones, the big ones, and the most advanced ones.
Honda robot Asimo was one of the first fully functional humanoid robots ever made. Even today it can still do many unique things.