"voluntary" means that the turtle isn't being forced to go in any
particular direction; it's just deciding to head where it doesn't see any
obstacles.
So, what's so great about turtles? Well, they can move around in land
and water, and they're powered entirely by whatever plants happen to be
around — which is more than we can say for any robot currently in
existence.As the researchers put it:"The system is suitable for
application in tasks traditionally carried out by mobile robots, such as
surveillance and reconnaissance, exploration and navigation, as well as
other missions dangerous for humans."
they pivoted about a fixed arm," Goldman explained."On soft sand,
they put their flippers into the sand and the wrist would bend as
they moved forward."
"In the robot, the free wrist does provide some advantage," said
Goldman."For the most part, the wrist confers advantage for
moving forward without slipping. The wrist flexibility minimizes
material yielding which disturbs less ground. The flexible wrist also
allows both the robot and turtles to maintain a high angle of attack
for their bodies, which reduces performance-impeding drag from
belly friction."
It's interesting to compare the movements of sea turtle
hatchlings to the movements of sea turtle adults because — at first
glance — the gait that the robot is using (pushing with two flippers
at once) seems to be the gait that the much heavier adults favor,
while the hatchlings prefer to alternate flippers for speed.
While Flipperbot itself is not going to be heading out to the
beach anytime soon, there are already beflippered robotic sea
turtles out there that may be able to benefit from this research
directly such as ETH's Naro-Tartaruga robot which is designed for
swimming and not for crawling around on land. It's entirely possible
that sea turtle wrists play a significant role in swimming efficient,
too. If Naro-Tartaruga could one day make it onto a beach, it would
add a huge amount of versatility to the robot.
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