Tech Briefs Magazine - August 2024 - MD-19

Tactile Sensing Strategy Enables Accurate Object
Detection
A new method incorporates thermal sensations for more robust and accurate robot perception.
Applied Physics Review, Melville, NY
T
oday's intelligent robots can accurately
recognize many objects through vision
and touch. Tactile information, obtained
through sensors, along with machine
learning algorithms, enables robots to
identify objects previously handled.
However, sensing is often confused
when presented with objects similar in
size and shape, or objects unknown to
the robot. Other factors restrictive to
robot perception include background
noise and the same type of object with
different shapes and sizes.
In Applied Physics Reviews, by AIP
Publishing, researchers from Tsinghua
University worked to break through the
difficulties of robotic recognition of various
common, yet complex, items.
Humans possess many different types
of touch sensing, one of which is thermal
feeling. This allows us to sense the
wind blowing, perceive hot and cold,
and discriminate between matter types,
such as wood and metal, because of the
different cooling sensations produced.
The researchers aimed to mimic this
ability by designing a robotic tactile sensing
method that incorporated thermal
sensations for more robust and accurate
object detection.
" We propose utilizing spatiotemporal
tactile sensing during hand grasping to
extend the robotic function and ability to
simultaneously perceive multi-attributes
of the grasped object, including thermal
conductivity, thermal diffusivity, surface
roughness, contact pressure, and temperature, "
said author Rong Zhu.
The team created a layered sensor
with material detection at the surface
and pressure sensitivity at the bottom,
with a porous middle layer sensitive to
thermal changes. They paired this sensor
with an efficient cascade classification
algorithm that rules out object
types in order, from easy to hard, starting
with simple categories like empty
cartons before moving on to orange
peels or scraps of cloth.
To test the capabilities of their
method, the team created an intelligent
robot tactile system to sort garbage.
The robot picked up common
trash items, including empty cartons,
plastic bags, plastic bottles, napkins,
sponges, orange peels, and expired
drugs. It sorted the trash into separate
containers for recyclables, food scraps,
hazardous waste, and other waste.
Their system achieved a classification
accuracy of 98.85 percent in recognizing
diverse garbage objects not encountered
previously. This successful garbage
sorting behavior could greatly reduce
human labor in real-life scenarios
and provide a broad applicability for
smart life technologies.
Future research in this area will focus
Recyclable Waste
Hazardous
Waste
Kitchen
Waste
Other Waste
Successful garbage sorting by an intelligent robot tactile system. (Image: Qian Mao and Rong Zhu/AIP
Publishing)
on enhancing robotic embodied intelligence
and autonomous implementation.
" In addition, by combining this sensor with
brain-computer interface technology, tactile
information collected by the sensor
could be converted into neural signals acceptable
to the human brain, re-empowering
tactile perception capabilities for people
with hand disabilities, " said Zhu.
For more information, contact Wendy
Beatty at media@aip.org; 301-209-3090.
Miniature 3D-Printed Actuators to Control Soft Robots
Potential applications include small-scale soft robots, shape-shifting machines, and biomedical
engineering.
North Carolina State University, Raleigh, NC
esearchers
R
from
North
Carolina
State University have demonstrated
miniature soft hydraulic actuators that
can be used to control the deformation
and motion of soft robots that are less
than a millimeter thick. The researchers
have also demonstrated that this techMotion
Design, August 2024
nique works with shape memory materials,
allowing users to repeatedly lock the
soft robots into a desired shape and return
to the original shape as needed.
" Soft robotics holds promise for many
applications, but it is challenging to design
the actuators that drive the motion
of soft robots on a small scale, " said Jie
Yin, corresponding author of a paper on
the work and an associate professor of
mechanical and aerospace engineering
at NC State. " Our approach makes use
of commercially available multi-material
3D printing technologies and shape
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Tech Briefs Magazine - August 2024

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