Thursday, April 06, 2006

Rehabilitation Robot Brings Hope

Amazing robot suit -- HAL A robot suit HAL (hybrid assistive limb) has been developed that could help older people or those with disabilities to walk or lift heavy objects. HAL is the result of 10 years' work by Yoshiyuki Sankai of the University of Tsukuba in Japan. As we know, the muscles of human body move according to the signal transmitted from human brain. In HAL, a "bio-cybernic" system uses bioelectric sensors attached to the skin on the legs to monitor signals transmitted from the brain to the muscles. This can be done because when the brain is transmitting some signal to the muscle, a detectable current is generated at the surface of skin. This current is picked up by the sensor and sent back to the computer. This current is then translated to some other signal which can be recognized by the controlling system and used to control the electric motors at the hips and knees of the exoskeleton. The motors at the hips and knees can respond to the signal in a fraction of a second. In fact, it responds even faster than the muscles do. That is why it can help the human body move so efficiently. As we can see from above, the bio-cybernic system controls the movement of the individual parts of human body such as hips, knees, feet, etc. The coordination of these movements is mandatory. Therefore, a second control system is used to provide autonomous robotic control of the motors to coordinate these movements and make a task easier overall, helping someone to walk, for instance. This system activates itself automatically once the user starts to move. The first time they walk, its sensors record posture and pattern of motion, and this information is stored in an onboard database for later use. When the user walks again, sensors alert the computer, which recognizes the movement and regenerates the stored pattern to provide power-assisted movement. These two control systems interact with each to complete the task. The actions of both systems can be calibrated according to a particular user's needs, for instance to give extra assistance to a weaker limb. Lokomat – savior of paralyzed people A robotic device that may help people with paralysis to walk again was unveiled for the first time in the United States at the Rehabilitation Institute of Chicago. This robotic device is called Lokomat. It gives hope to people with paralysis by retraining them to walk as shown in the picture. Lokomat consists of a powered exoskeleton robot. It delivers power to the hip and knee of a person whose legs are strapped to the machine. This device suspends the patient in a harness over a treadmill, while a robot helps swing the legs. The computer synchronizes the treadmill with the body's pace. This repetitive training in movement may help the gait pattern generators thought to be located in the lumbar area and might, in time, help patients redevelop and regain functional walking patterns. Lokomat offers people with paralysis other benefits as well. For instance, regular therapy helps prevent limbs from deteriorating, by strengthening muscles and bones. Also, weight-bearing exercise helps individuals with paralysis to ward off the threat of osteoporosis.


Medical said...

U0204570 Tang Shao Qiang

This technology indeed is a good news for patients with spinal cord injuries and people with inborn movement disbilities. However, while robots prove to useful in various human endeavours, I am concern with the affordability and reliability of such machines to those who need them. Currently, such rehabilitation robots cost tens of thousands of dollars each. Will most rehabilitation centres be able to purchase them and will the patients be able to pay for their usage? In addition, since these robots are in close proximity with the human body, considerations have to be given to the chances that they will malfunction and the possible injuries that might be brought upon the patient when that happens. There should be emergency measures and systems in place to disable the robot quickly should it malfunction.

An improvement can be done to the current system. Right now, the robot will execute the movements as dictated by the nervous signals generated by a patients thoughts when he expects himself to activate a particle limb. To achieve better rehabilitation results, maybe the inventors could consider installing some pressure sensors to moniter the force exerted by the patient's own muscles. These information can be fedback to the controllers of the robot so that they can do real-time adjustments of the force produced by the robotic aids to complement that initiated by the patient for a certain movement. These gives the body a chance to gradually adapt to non-assisted movement rather have total reliance on the robot.

Security said...


This technology is what I consider more realistic to realize at the current phase. The reasons are as follows:
1. the potential needs: from business point of view, the needs of the disable and its family is to live normally is both urgent and real. They will pay money for themselves or relatives to stand up and walk independently. It is something that fulfill the great needs.
2. from technological point of view: the advances in life sciences of ECG and signal processing have provided us solid ground for this type of applications. The reliable ECG signals can be a very good control source.
3. Advances in power and control technology have make the mechanical control more reliabel and the power consumption lower which previously inhibited the development of this kind of technology.

But cautions must be taken for the followings:
how can we make it error-proof?
how can we make it more smart, so that it likes part of our body? Train them using Back-track algorithm, ANN?
There are still lots of questions waiting us to answer.


Medical said...

U0204500 Ong Phian Ting

This technology would certainly be a great help to the world in the near future. With lower birth rates and aging of the population, this equipment would help the aged to move about with less reliance on others.

Furthermore, i have seen in the news a few months back, they actually have similiar equipments (not sure if they are the same) which are quiped on the nurses in hospital. In this way, even the smallest built nurse would be able to lift a patient off the bed. This would bring good news to hospital who are suffering from nurse shortage.

Exploration said...

u0204593 Chiam Lee Chuan

I believe this rehabilitation robot would bring a new lease of life to those patients that suffered permanent spinal cord injures and have to stay on the wheelchair for the rest of their life. If this technology were to be applied to elderly, i'm sure it would reduce their dependency on health care worker. said...

I have post polio syndrom and use devices for both legs, my musscle are not strainth, let me know if hal 3 or 5 could be useful to me and what about the price, my e mails is