Uniting Data and Technology to Empower Tomorrow's Climate Solutions
The U.S. Greenhouse Gas Center opens up access to
trusted data on greenhouse gases. This multi-agency effort consolidates
greenhouse gas information from observations and models. The goal of the
US GHG Center is to provide decision-makers with one location for data and
analysis.
This initial two-year demonstration phase creates a
way to explore and analyze U.S. government and other datasets, targeting three
greenhouse gas areas of study, as shown below. The US GHG Center also
encourages stakeholder feedback and ideas for future expansion.
Problem:
Irodov, problem 1.52., it says that acceleration is constant in magnitude and
pointing permanently towards the center of the wheel. `vrai ou faux?
A wheel rolls on a horizontal surface
without slipping. Also rolling is the acceleration vector (red). It has two
components. Tangential acceleration (orange) changes the magnitude of the
velocity vector of a point on the rim of the wheel. Normal acceleration (green)
changes its direction.
Schematic illustration and images of
PHCE camera and integrated components. Credit: Zhiyong Fan
A
team of engineers and roboticists at Hong Kong University of Science and
Technology has developed an electronic compound eye design to give robots the
ability to swarm efficiently and inexpensively.
In their paper published in the journal Science Robotics, the group describes the
inspiration for the design and how well it worked when tested in a flying robot.
Most robot eyes are based on the
standard camera concept—images are captured using a lens that allows for
high-resolution processing. But this approach is expensive. For that reason,
roboticists seek to build robots with compound eyes, similar to those found in
many insects.
Compound eyes, as the name suggests,
have multiple small lenses covering a hemisphere—in insects, the images are
stitched together in the brain, allowing the insect to see. Doing the same with
electronic eyes has proven to be a formidable task because of the problem of
affixing flat lenses onto a curved surface. The team in Hong Kong has overcome this problem with
a completely different approach.
Overview of a biomimetic PHCE for robot vision.
Credit: Zhiyong Fan
To create their compound eye, the
research team started with a plastic hemisphere with multiple pinholes drilled
through its surface to allow light to enter. They then plugged each of the
holes with a perovskite nanowire that directs the light onto an individual
light sensor. All the light sensors were then connected to a central processer,
which, like the insect eye, stitches the images together to form unified
images.
The design, the researchers claim,
allows for an inexpensive electronic eye for use in certain types of robots.
They note that their design has a field of view of 140 degrees; when paired
with another of the same type of eye, the field increases to 220 degrees.
Motion tracking of the on-drone PHCE vision
system. Credit: Zhiyong Fan
To test their design, the team
installed a pair of the compound eyes onto a flying drone, which they used to track
the movements of a four-legged walking robot. They suggest their design would likely be most suitable for robots that
fly together as a swarm or perhaps be used in autonomous vehicles.