by Brian Orlotti
A four-legged robot being developed to carry cargo for the US military now sports an arm strong enough to lift and throw 50 pound (23kg) cinder blocks.
This robot, BigDog, is made by Boston, MA based firm Boston Dynamics and funded by the US Army Research Laboratory (ARL). Designed mainly for military use, BigDog has been in development since 2005 and is the size of a large dog or pack-mule.
BigDog’s legs mimic an animal's legs, and are able to absorb shocks and recycle energy as the robot moves around. It is powered by an engine which drives a hydraulic pump to send oil under high pressure around its plumbing in order to animate its limbs. The robot’s small mule arm attached to its ‘head’ can help soldiers pick up and carry heavy loads as well as smaller tasks.
Boston Dynamics reps say that in addition to hauling cargo, BigDog’s technology shows great promise in the area of search and rescue. The robot can already move over rugged terrain (or even slippery ice) while carrying a 340 pound (154 kg) load. It can navigate autonomously and also obey voice commands.
And BigDog is just one of a range of robots developed by Boston Dynamics. Others include:
- Alpha Dog - AKA the Legged Squad Support System (LS3), is being developed for use by the US Marine Corps. The LS3 is able to follow a human (or a squad of them) around while accepting voice commands. The Alpha Dog also has improved walking capabilities that allow it to cross rough terrain. The LS3 even has the ability to right itself if it, for instance, tumbles down a hill. Alpha Dog’s roles could include carry a Marine squad’s bags or even acting as a squad support weapon (if armed).
- Cheetah - a headless machine whose body is inspired by the fastest land animal on Earth. By angling the feet and allowing its back to flex during strides, the designers created a more efficient range of motion, allowing for higher speeds. Cheetah can reach 28.3 mph (45.5 km/h) on a treadmill, faster than the fastest human. Possible battlefield roles for Cheetah include fast cargo delivery and even hit and run attacks on enemy positions.
- Petman - A two-legged human-like walking robot developed for use by the US Army to test chemical protection clothing. It performs heel-toe walking at up to 3.2mph (5.14 kmh) and can be pushed without falling over. It can also crawl and do a range of other movements that soldiers may perform so as to ensure accurate testing for the suits. Petman is even capable of sweating and controlling its own temperature. Petman aims to be as realistic a test subject as possible.
- Sand Flea – AKA Precision Urban Hopper, is a DARPA-funded robot capable of leaping over 10 meter tall obstacles. This height can be limited if necessary so as to minimize impacts. The jumping mechanism works by Sand Flea rearing up on two rear arms and firing a piston. With a small battery to power the on-board electronics, Sand Flea can be remote controlled via GPS link for long-range surveillance. There’s even an onboard stabilization system to ensure smooth video capture during the jump. A CO2 container allows the 11 pound robot 25 jumps before a refill is needed. The Sand Flea is now in use in Afghanistan supporting US troops by allowing areas to be investigated before any soldiers set foot on the ground. The robot’s jumping ability will be very useful for traveling around major obstacles such as walls, or for gaining higher ground by jumping on to a roof.