Earlier a robot
made of ultralight carbon-fiber can stand or slowly walk on water. The
principle it uses is borrowed from insects -- surface tension tends to prevent
the water's surface from breaking, and the robot's legs from sinking in.
Recently the first bio-inspired microbot is capable of
not just walking on water but jumping up and down on the water's surface like
the insect, a study shows.
Qinmin
Pan and colleagues from Harbin Institute of Technology and the National Natural
Science Foundation of China, reported a number of advances toward tiny robots
that can walk on water.
However,
even the most advanced designs, including one from Pan's team last year - can
only walk on water. Pan noted that real water striders actually leap, the
journal Applied Materials & Interfaces reported.
Pan's
group looked for novel mechanisms and materials to build a true water-striding
robot, according to a Harbin Institute statement. The weight of the microrobot
is equal to that of about 390 water striders, one might expect that it will
sink quickly when placed on the water surface," the report noted. Instead,
the mechanical creature stands effortlessly on water surfaces and also walks
and turns freely
Making a jumping robot is
difficult because the downward force needed to propel it into the air usually
pushes the legs through the water's surface.
Using porous, super
water-repellant nickel foam to fabricate the three supporting and two jumping
legs, the group made a robot that could leap more than 5.5 inches, despite
weighing as much as 1,100 water striders.
In experiments, the robot
could jump nearly 14 inches forward -- more than twice its own length --
leaving the water at about 3.6 miles per hour.
The study authors report
that the ability to leap will make the bio-inspired microrobot more agile and
better able to avoid obstacles it encounters on the water's surface
Credit:American chemical society NEWS