Since science fiction first came up with the concept of robots, it has been assumed that, at some point in the future, human troops will be joined on the front line by anthropomorphic, or humanoid, robots. Strategic Defence Intelligence investigates a new programme that explores this theme further and incorporates some new ideas.

To date, land robots in combat use have followed a fairly limited set of designs. They are generally a metre or two in size, tracked or wheeled, low to the ground and fitted with bomb disabling or combat equipment. The most used bomb disposal robot is the Wheelbarrow, while combat models include the Foster-Miller TALON and the iRobot Warrior.

Biomimetic robots – those which mimic forms in nature – have been widely explored, but so far have not made it past early trials. These include robots that walk on eight spider-like limbs to navigate difficult terrain, wall-climbing robots that can ascend vertical surfaces using gecko-like feet, and Defense Advanced Research Agency (DARPA)-funded research into ‘flying’ tree snakes that fling themselves from tree to tree and could form the basis of future unmanned aerial vehicles (UAVs).

The closest the military has come to introducing humanoid robots are the exoskeletons developed by Lockheed Martin and Raytheon. Currently undergoing tests, these ‘wearable robot suits’ help troops lift and manoeuvre far heavier weights than they would be able to unaided.

Now, DARPA is funding research into two innovative robot designs by dynamic robot specialist Boston Dynamics; one that walks like a human but can use its hands for support, and a cheetah-like design that can outrun a person and display great agility.

The ATLAS robot is human-shaped with a torso and limbs. It will move mainly on two legs but when faced with difficult terrain, will be able, like a human, to go down on all fours for extra support and balance.

Rob Playter, ATLAS principal investigator and vice president of engineering at Boston Dynamics, said of the design, “Unlike Honda’s Asimo and most other humanoid robots you’ve seen, ATLAS will walk just like a man, using a head-to-toe walking motion, long strides and dynamic transfer of weight on each step.”

The company will use the experience it gained in developing Petman, an anthropomorphic robot developed for the US Army with advanced behaviour.

The CHEETAH robot will look like its feline namesake, with four legs, a flexible spine, an articulated head/neck and possibly a tail. The company claims that not only will it be able to run faster than human runners, but it will also outpace all legged robot rivals.

The CHEETAH will also be highly agile, with the ability to make tight turns, zig-zag or stop suddenly on the spot. Using rapid acceleration and advanced control systems, Boston Dynamics says it could even leap across gaps or swing from one handhold to the next.

The research this programme will involve is likely to inform robot and control system design for future military robots. But, like their biomimetic and anthropomorphic robot predecessors, the ATLAS and CHEETAH robots are unlikely to be bounding across battlefields any time soon.