TRYING TO CLEAN UP
Xiaomi recently introduced its $250 Mi robot vacuum that hopes to take on the iRobot Roomba. The Mi vacuum can clean all floor types and features a Laser
Distance Sensor (LDS) and Simultaneous Localization and Mapping (SLAM) to scan its
surroundings 1,800 times per second in 360 degrees.
It also has 12 sensors, including ultrasonic radar, cliff sensor, gyroscope and
accelerometer, three processors and four CPU cores for real time mapping and
positioning, and a main brush with adjustable height for uneven surfaces.
The Xiaomi Mi robot vacuum features a Nidec brushless DC motor, claims to be
ultra quiet, and uses a 5,200 mAh battery that promises 2. 5 hours of cleaning. Like
other Mi Ecosystem products, Mi Robot Vacuum pairs and integrates with the Mi
Home app. It can be controlled remotely where users can power it on or off, and it
also lets you set regular cleaning schedules.
You’ve probably seen robots that walk, roll, climb, and open doors. However, the Ghost Minitaur robot does all of these
things in one package. It’s a medium-sized quadruped walker that
stands well under a half meter tall.
Built by Ghost Robotics, Minitaur can travel in a front-to-back
orientation or at a slower side-to-side orientation in which it rolls
over itself in either direction. If that’s not impressive enough,
Minitaur can also open doors with a “jump and swipe” maneuver,
and climb fences by carefully manipulating its powerful legs.
Minitaur does all of this with just four legs that each have two
motors. The mechanical portion of Minitaur seems simple at first, but a closer look shows it is extremely well
designed. Each leg system is offset at five degrees and is built as 5-bar linkage assembly. With this linkage setup,
Unbelievably, Minitaur was built with off-the-shelf parts, and because it uses no gearbox
between the motors — which would add extra
inertia, backlash, and friction — the force “felt”
by the legs can more easily be sensed by the
control unit and be used while moving. This
feedback transparency is where the term
“Ghost” comes from.
Minitaur currently is operated as a remote
controlled vehicle. The lower-level operations,
such as how each motor needs to rotate at a
certain instant and force feedback, is handled by
the onboard processor: an STM32F series
microcontroller that can be programmed in an
Arduino environment. The control board also
includes connections for a Raspberry Pi.
bots IN BRIEF
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