FYI,

Will the next generation of space robots look like this?

"Tripedal Robot Swings Itself into Action"
New Scientist
http://technology.newscientist.com/article/dn12668-tripedal-robot-
swings-itself-into-action.html

: A three-legged robot with an unconventional and graceful walk has
: been developed by US researchers. Like humans, it exploits gravity
: to save energy with each step, but it also flips its entire body
: upside-down with each stride.

: The fearsome alien tripods in HG Well's book The War of The Worlds
: are described as moving like "a milking stool tilted and bowled
: violently along the ground".

: STriDER (Self-excited Tripedal Dynamic Experimental Robot) has a
: far more graceful, and acrobatic, gait (see video top right) that
: sees its body flip 180 degrees with each step. A second video
: (bottom right) explains more about the project and shows the
: initial prototype.

: To take a step forwards, the robot shifts its weight onto two of
: its legs, allowing itself to fall forwards away from the third leg.
: Its body then flips upside-down and the third leg swings up between
: the other two just in time to catch the ground and return STriDER
: to a stable tripod stance. To change direction, the robot simply
: switches its choice of swinging leg.

: Human-like walkAlthough STriDER's body shape is like nothing in
: nature, its gait is meant to closely mimic the way biological
: organisms walk. The aim is to minimise the complexity of
: controlling each limb, and to reduce overall energy use. The first
: prototype stands 1.8 metres tall, while the latest incarnation is
: slightly shorter, at 0.9 metres.

: "STriDER's gait is closer to that of a human walking than most
: bipedal humanoid robots you see today," explains Dennis Hong at
: Virginia Tech, US, who leads the project. "This is how we humans
: walk, we do not actively control our knees, we just let them
: swing."

: The robot is not designed to be a load carrier, Hong explains. "Its
: purpose is for deploying sensors to difficult-to-access areas," he
: told New Scientist. "Since STriDER is tall by nature, it is great
: for deploying cameras."

: Stable designThe most successful autonomous robots often resemble
: remote-control cars, he points out, and cannot see above obstacles.
: "I've never heard of a robot with a three-legged design before, but
: I can see the advantage," says Dave Barnes, who works on locomotion
: for planetary rovers at Aberystwyth University, UK. "It's like a
: biped with a walking stick."

: Although bipedal humans and robots can move quickly, they have to
: expend energy just to keep upright when they are not moving, he
: points out: "A tripod stance is very stable, you can just lock the
: joints."

Videos

http://technology.newscientist.com/article/dn12668-tripedal-robot-
swings-itself-into-action.html

http://technology.newscientist.com/article/dn12668-tripedal-robot-
swings-itself-into-action.html

Mark Reiff