B.Ag. Sc.(Hons.), Ph. D.
After working as a plant physiologist and science
educator, Dr Catchpoole worked for many years
as a scientist/speaker for Creation Ministries
International (Australia). He continues to write for
CMI. For more: creation.com/catchpoole.
Credit: Seoul National University
From The American Association for the Advancement of Science, Two leaps for ward for robot locomotion. Reprinted with permission.
Ten years on, and researchers intent
on copying the leaping prowess of the
water strider have made impressive
progress. 4, 5 Using high-speed cameras
and other equipment, the researchers
observed that the water strider’s legs
accelerate gradually, so that the surface
of the water does not retreat too quickly
(which would mean losing contact). They
found that the maximum force exerted
by the water strider’s legs approaches,
but never exceeds, the opposing vertical
component of the water’s surface tension
(and therefore the legs don’t sink). They
also observed that water striders sweep
their legs inward to lengthen the time
period they can push against the surface
of the water. Furthermore, the curved
tips of their legs are just the right shape
to adapt to the dimples that form on
the water’s surface when the legs push
downwards, thus enhancing to the fullest
possible extent the surface tension on
the legs. All of this works to maximize
the overall force for their jumps.
Armed with this new knowledge,
the engineers have built their own
lightweight robot which can jump 14
cm ( 5. 5 inches) above the surface of the
water—about the same as the length of
its ‘body’. Like the insect water strider,
the robot can jump on land as well as
water, but at this stage it can jump once
only, and lands randomly. “[U]nlike a
living water strider, this first generation
of robo-striders can’t get back up after a
splash—or crash—landing.” 6
Ultimately the researchers aim
to build a robot capable not only of
controlled landings and repeat jumps,
but also of carrying the necessary electronic equipment (e.g. batteries and
sensors). They foresee it would be useful
for surveillance, search-and-rescue
missions and environmental monitoring.
Incidentally, the jumping mechanism used in the robots was not copied
from the water strider, but from the flea.
So (at least) two creatures provided the
inspiration for the robot. As Kyu-Jin
Cho, one of the researchers and Director
of the Biorobotics Laboratory at Seoul
National University, said, “Natural
organisms give a lot of inspiration
to engineers.” 7
Those ‘natural organisms’ didn’t
originally come about naturally, but
supernaturally, just as we did—but
with one important difference. Unlike
water striders and fleas, we were created
in the image of the Creator Himself
(Genesis 1: 26–27), so no wonder man
alone among all the creatures has the
capacity to study and even copy what
God has made. And even if one of our
creations might eventually match some
aspect of His handiwork, we should
never forget who thought of it first.
References and notes
1. E.g. see creation.com/biomimetics and
2. Quoted in ‘Mech Nuggets’, Carnegie
mech—carnegie mellon 10(1): 17, Fall 2006;
3. Suhr, S., Song, Y., Lee, S., and Sitti, M.,
Biologically inspired water strider robot,
Robotics: Science and systems, MIT, Boston,
June 2005, nanolab.me.cmu.edu.
4. Vella, D., Two leaps forward for robot
locomotion, Science 349(6247):472–473,
2015; doi: 10.1126/science.aac7882.
5. Koh, J., Yang, E., Jung, G., Jung, S., Son, J.,
Lee, S., Jablonski, P., Wood, R., Kim, H.,
Cho, K., Jumping on water: Surface tension-dominated jumping of water striders and
robotic insects, Science 349(6247):517–521,
2015; doi: 10.1126/science.aab1637.
6. Schwartz, S., Robot springs off water:
Inspired by water striders, lightweight bots
take advantage of surface tension to leap,
sciencenews.org, 30 July 2015.
7. Choi, C., Bug Bots! These insect-inspired
robots can jump on water, livescience.com,
3 August 2015.
A water strider (insect, black, in forefront) next to two robots (larger, arrowed)
that were inspired by it.
Water strider mimic. Koh et al. have designed a robot that can jump from a water surface without sinking.
CREATION.com 13 Creation 39( 3) 2017