Friday, March 30, 2012

Robotic Exoskeleton

The robotic exoskeleton has been a mainstay of science fiction for as long as I can remember. Popular renditions include comic book icon Iron Man, Halo's MJOLNIR Powered Assault Armor, and the Power Loader Sigourney Weaver used in the movie Aliens.  Being a fan of Japanese anime, my personal preference  would be something more along the lines of the Robotech Cyclone pictured below.  I mean, who wouldn't want a motorcycle which turns into a suit of protective power armor?

As with much of our currently realized technology, science fiction writers & artist first dream it, then the scientist, technicians and engineers build it.  This seems to be true with the exoskeleton as well.  The first true attempt at a robotic exoskeleton was undertaken by General Electric in the 1960s.  The suit, named Hardiman, was designed to mimic natural movements and to provide the wearer with enough strength to lift up to 1500 lbs. Unfortunately , Hardiman’s size, weight, and lack of stability, kept the machine from functioning properly and   as a result the project never went beyond an experimental prototype.  

Though initial attempts at a working exoskeleton were not successful, continued efforts in the field have resulted in some truly amazing devices.  

Medical Uses
Rex Bionics
Rex is a robotic exoskeleton worn alongside the legs which is able to help mobility impaired users to walk again.  The system is operated with a control pad and joystick thus allowing someone who has lost all movements in the lower limbs to use the device.  It weighs 84 pounds and costs about $150,000 (ouch).

eLegs is a similar device to the Rex except that in addition to the mechanical legs, a set of crutches containing sensors are used to control it's movements.  In exchange for tying up both arms with crutches, it seems as if users are able to move much faster with eLegs than with Rex.  It ways about 45 pounds and cost $100,000.

Military Uses
The HULC (Human Universal Load Carrier) is a lower body exoskeleton which enables the user to carry up to 200 pounds with little effort and to run up to 10 mph (a 6 min mile) for short bursts.   Like the above devices, HULC doesn't do anything to enhance arm strength but is still pretty cool.

Now we are getting to the really cool stuff.  The XOS 2 by Raytheon is an impressive full body exoskeleton which essentially provides the wearer with superhuman strength and endurance.  The suit enables a 17:1 lifting ratio, so lifting 200 pounds feel more like 12 pounds.  As the video demonstrates, the suit seems quite responsive and maneuverable.

Mixed Use
HAL (Hybrid Assistive Limb) developed by the Japanese company Cyberdyne,  comes in two forms.  The HAL 3 is strictly a lower body exoskeleton while the HAL 5 is a full body system.  Sensors on the skin are used to control the suits fluid movements.  Currently HAL 5 allows the user to lift and carry about 5 times as much weight as he or she normally could. The HAL 5 weighs about 50 pounds and depending on the source, I have seen it priced somewhere between $14,000 to $50,000 (substantially less than the other suits).  Most important is that the suit looks very cool, but what would you expect from the Japanese.