TechTheDay

Technology can help paralyzed people in walking again. Almost everyone already expects this possibility. Robotics and other forms of technologically-driven body augmentations will eventually become useful to paraplegics. Very soon, however, we can see this technology in real-world action, in a practically useful form.

In the upcoming World Cup 2014 opening, a robotic technology that makes paraplegics walk will debut. Before the current year’s World Cup starts at Arena Corinthians in Sao Paulo, a young paralytic Brazilian man will walk into the midfield and have the honor of doing the first kick as part of the opening ceremony. All of this will be made possible by a robotic exoskeleton that is mind-controlled by its wearer.

The exoskeleton looks highly conspicuous. No, don’t expect something compact and seamlessly attached to the human limbs. The suit is rather bulky and it makes the person wearing it look big and heavy. Nevertheless, it is built with lightweight alloys. It relies on hydraulics instead of the recently developed artificial muscles made with polymer fiber.

Serving as the final product of the years of R&D work undertaken by international scientists and engineers, the exoskeleton is the output of the Walk Again Project under the coordination of Gordon Cheng at the Technical University in Munich.  There have been nine paraplegic persons trained to wear the robotic exoskeleton. Three of them will be attending the World Cup opening ceremony with one chosen to do the demonstration in the middle of the field.

So how does the exoskeleton work? The mechanics are detailed below:

1. The wearer has to don a cap to control the exoskeleton.

The cap is equipped with 32 electrodes designed to detect brain waves or EEG signals. The cap needs to cover most part of the top of the head to be able to collect all the signals needed to run the suit.

2. A backpack-like component contains the computer and other major parts that power the exoskeleton.

The computer that runs the exoskeleton is located in the backpack-like part. It is a rather large component but the design calls for such size and weight to facilitate the balancing of the exoskeleton. Obviously, the paraplegic wearer will not have the ability to balance himself, along with the exoskeleton, using his or her own feet. The exoskeleton is hence equipped with gyroscopes and has to have some reliable amount of weight to be able to automatically balance itself. The backpack-like part also houses the battery and hydraulic system that moves the limbs.

3. The limb parts are equipped with sensors to provide stepping feedback to the wearer.

The exoskeleton has limbs that enable movements and facilitate control. There are two limbs that basically serve as arm rests. These limbs feature a system that conveys signals from the sensors on the foot plates (of the two lower limbs) to inform the wearer if contact with the ground has been made. This makes walking somewhat more intuitive for the wearer. Since it is still not possible to directly inform the brain about the interactions on the limbs, feedback is coursed through the arms to let the users know how to “mind-control” the exoskeleton appropriately.

Challenges

This robotic suit or exoskeleton is still far from perfect. There are still many challenges in using it or in making it a viable alternative to wheelchairs. The following challenges and drawbacks are worth noting:

• Price – Building and using the exoskeleton is of course still very costly. It is unlikely to be available to most paraplegic people.

• Short Battery Duration – The battery installed can only last for two hours. Despite the huge size, it does not pack enough power to last for at least half a day.

• Comfort Issues  – Being inside the bulky exoskeleton may not be very comfortable for most people especially after a long time of use. However, those who have tried using it claim to have very good experiences. One of them even said that it feels like walking on the beach.

Using robotics to facilitate walking for physically handicapped people is the expected route to take as technology advances. The exoskeleton that will be demonstrated in the World Cup 2014 is definitely a welcome development. Even if it fails to become a viable aid for paraplegic people, it’s still great to know that it is now possible to control robots using brain waves. It won’t be long before the technology progresses and enables better ways of manipulating robotic limbs or corporal augmentations.