Great grandma can soon put aside that powered wheelchair she uses to terrorize the residents at her rest home. Japan’s robotics venture Cyberdyne’s robot-suit "HAL" (Hybrid Assistive Limb) is now available for rent and is being tested on the streets of Tokyo:

HAL, an exoskeleton, is a mind-controlled wearable machine that gives humans enhanced mobility.

The HAL exoskeleton –- described in a popular article for the first edition of h+ ("I am Ironman!") – helps the wearer to carry out a variety of everyday tasks, including standing up from a chair, walking, climbing up and down stairs, and lifting heavy objects. The suit can operate for almost five hours before it needs recharging.

Cyberdyne’s HAL isn’t quite ready for great grandma just yet. But until it is, Toyota researchers in Japan have built a brain/machine interface (BMI) that has been demonstrated to control a wheelchair using a person’s thoughts. The wheelchair enables a person to make it turn left or right or to move forward simply by thinking the commands –- and it has a 125 millisecond response time.

The HAL exoskeleton, on the other hand, has robotic limbs that strap to your arms and legs — providing much fuller mobility than a wheelchair. The suit’s backpack contains a battery and computer controller. When a HAL-assisted person attempts to move, nerve signals are sent from the brain to the muscles, and very weak traces of these signals can be detected on the surface of the skin. The HAL exoskeleton identifies these signals using a sensor, and a signal is sent to the suit’s power unit telling the suit to move in synch with the wearer’s own limbs.

HAL comes in three sizes — small, medium and large and weighs in at 23kg (50.7 lbs). A single leg version rents for 150,000 yen ($1,570) a month, while a two-leg unit goes for 220,000 yen ($2,300) a month. Cyberdyne has yet to announce when HAL will go on sale to the public or what the price tag will be.

Great grandma won’t be the only one who will benefit from a thought-controlled exoskeleton. Seiji Uchida, paralyzed from the neck down for over two decades, was able to get within 500 yards of the summit of the 13,741-foot Breithorn Mountain in Switzerland with the help of a HAL exoskeleton worn by his friend Takeshi Matsumoto. Mr. Matsumoto was able to carry the quadriplegic Mr. Uchida because Matsumoto was wearing the exoskeleton. Imagine a next-phase exoskeleton that Mr. Uchida can control himself without the assistance of Mr. Matsumoto. HAL shows tremendous potential to help mobilize the disabled to perform day-to-day tasks.

If anyone is physically challenged, it’s the soldier carrying a huge load on the battlefield. Exoskeletons give soldiers the ability to move faster while carrying more weight. For nearly a decade, a project launched by the Defense Advanced Research Projects Agency has been looking at ways to help with the heavy lifting. The Exoskeletons for Human Performance Augmentation, a program with the goal “to develop devices and machines that will increase the speed, strength and endurance of soldiers in combat environments,” is a way to create super soldiers that can lift hundreds of pounds as easily as lifting 10 pounds and can run twice their normal speed.

Under contract from the Army, a team at Raytheon Sarcos, led by Stephen Jacobsen, built an exoskeleton called XOS. Looking something like Ripley wearing the industrial exo-suit power loader in the classic SF film Aliens, software engineer Rex Jameson used his XOS to run, jump, and even speed box a punching bag. Jameson also was able to do a lengthy series of reps on a weight machine using 200 lb weights. “He stopped because he got bored,” Jacobsen says, “not because he was tired.” Here’s a video of the Sarcos exoskeleton:

Cyberdyne’s exoskeleton is considerably more sleek and stylish. Tokyo rentals were initiated in August, 2009. Like Segways, the popular 2-wheeled, self-balancing electric vehicles now being using by police to patrol the streets of major cities, it’s easy to imagine Washington, D.C., Minneapolis, Denver, San Francisco, Chicago, or even Albuquerque providing exoskeleton rentals.

The next phase in bicycle rentals is high-tech bike-sharing systems — an investment in public bicycles worldwide. Walk up to a kiosk, swipe a credit or membership card and ride away. Return it there or at another station, like renting a luggage cart at the airport. Cyberdyne’s exoskeletons appear to be easier to use than bicycles, particularly for weary travelers. Why not rent an exoskeleton rather than a bicycle?

With fashionable cyborg exoskeletons now available for rent on the streets of Tokyo, can major U.S. cities be far behind?