Tube-shaped robots roll up stairs, carry carts, and race one another


Date:
September 22, 2021
Source:
Cell Press
Summary:
Researchers have designed a 4D-printed soft robot that
self-assembles when heated and can take on challenging tasks like
rolling uphill and navigating a bumpy and unpredictable landscape.



FULL STORY ========================================================================== Researchers have designed a 4D-printed soft robot that self-assembles
when heated and can take on challenging tasks like rolling uphill and navigating a bumpy and unpredictable landscape. The prototype, which is tube-shaped, appears September 22nd in the journal Matter.


========================================================================== "Like an insect with antennae, the robot can surmount a small
obstacle. But when the obstacle is too high, it will turn back," says
senior author Wei Feng, a materials scientist at Tianjin University in
China. "The whole process is spontaneous without human interference
or control." The robot starts off as a flat, rectangular sheet of
a 3D-printed liquid crystal elastomer, a type of stretchy plastic
material. When the surface beneath it is heated, the robot spontaneously
twists up to form a tubule resembling a spring. The change in shape under external stimulation adds time as a fourth dimension to the printing
process, making it 4D.

Once the robot forms a tubule, the contact from the hot surface induces
a strain in the material, which causes it to roll in one direction. The
driving force behind this motion is so strong that the robot can climb
up a 20DEG incline or even carry a load 40 times its own weight. The
length of the robot affects its velocity, with longer robots rolling
faster than their shorter counterparts.

The researchers captured videos showing off the robot's skills,
including a race between differently sized robots and another robot
carrying a cart. The videos also show how its behavior changes based on
its surroundings, with the robot either climbing up a step or changing directions when encountering an insurmountable obstacle.

For Feng, the behavior of the robot came as a surprise. "We processed
the liquid crystal elastomers into samples of various shapes through 4D printing and stimulated these samples with light, heat, and electricity
to observe their response," he says. "We found many interesting driving phenomena besides deformation." In the future, these soft robots may be
used to perform work in small, confined places like in a pipe or under
extreme conditions like a 200? surface. "We hope that soft robots will
no longer be limited to simple actuators, which can only change shape
in a fixed position," says Feng.

This work was supported by the State Key Program of National Natural
Science Foundation of China, National Key R&D Program of China, and
National Natural Science Foundation of China.

========================================================================== Story Source: Materials provided by Cell_Press. Note: Content may be
edited for style and length.


========================================================================== Journal Reference:
1. Zhai et al. 4D-printed untethered self-propelling soft robot
with tactile
perception: Rolling, racing, and exploring. Matter, 2021 DOI:
10.1016/ j.matt.2021.08.014 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/09/210922121823.htm

--- up 2 weeks, 6 days, 8 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)