bots IN BRIEF
Here's a new robotics term for you: multi-modal locomotion. It
means locomoting in multi-modes, which is basically getting
around in more than one different way. Most animals are
multi-modal. They can walk and swim, or walk and fly. This
isn't a coincidence because there are clear advantages to
being able to move multi-modally, with capability and
efficiency coming out near the top of that list.
The disadvantage is that, generally, you need a
substantial amount of extra hardware for each mode of
locomotion. However, EPFL has managed to create a UAV that can use
its wings to walk.
This robot takes advantage of "adaptive morphology," where you've got one
structure (the wings, in this case) that can be used for multiple locomotion modes. In a
search and rescue situation, you might use a capability like this to fly around and get a good
overview of an area, and then land and crawl around under some bushes if you spot something
Also, small UAVs tend to land badly, and being able to move around (even just a little bit) vastly
improves the potential for returning to the air successfully.
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HyQ is a quadruped robot designed for rough terrain missions.
Created by a team at the Istituto Italiano di Tecnologia (IIT), HyQ uses
hydraulic actuators which allow it to move quickly and nimbly
with an eerie animal-like quality. Now, HyQ has learned
another important skill in life: how not to fall on its face when
it stumbles on an obstacle.
Falling is a major problem for legged robots. Unlike animals
and (most) humans, robots don't handle falls very well. Their
stiff metal bodies can't absorb shocks, and a crash often means
broken parts and costly repairs. So, robots designed to operate
in real world conditions need to learn how to avoid falls.
Cameras and sensors like LIDAR help detect and avoid
obstacles, but in some situations a robot can't rely on vision.
For example, in thick vegetation or if smoke is present.
To overcome this obstacle (quite literally), HyQ is learning
to reflexively react when its legs hit an object on the ground.
This reaction has to be very fast — especially when the robot
is trotting (HyQ can reach two meters per second) — or else
it will lose its balance and collapse.
The IIT researchers have developed and implemented a "reflex
algorithm" that allows HyQ to step over high obstacles without prior
knowledge of the terrain.