REVIEWMyCobot 280 Pi
Elephant Robotics

magpi.cc/mycobot280

From £651 / $799

This high-quality, robust robot arm has a range of optional
attachments. By Phil KingSPECSFEATURES:

6DOF, 330°
rotation range,
280 mm radius,
up to 250 g
payload, LEGO
interfaces onbase and head,
Raspberry Pi 4

CONNECTIONS:

2 × USB 3.0, 2 ×USB 2.0, Ethernet,
micro-HDMI,
GPIO breakout
headers, USB-C,
headphone jack,
Grove and servo
connectors

W

ith a working rotation arc of 330° andradius 280 mm from its base joint, theMyCobot 280 is a high-quality robot
arm with a long reach.
Powered by a built-in Raspberry Pi 4, it has
six degrees of freedom (6DOF) thanks to half adozen joints (equipped with bearings) controlled
by large servos, all enclosed in protective plastic
casings. Between two horizontal joints for the baseand ‘head’ are three vertical ones; by varying theangles of the joints, each of which has a rangeof 330°, the arm can flex into pretty much any
position as it moves smoothly.
A sixth joint rotates the end of the head, towhich you can attach various accessories using
tiny LEGO connectors inserted into its grid of holes
and those on the accessory, making them easy tofit and remove.
A similar LEGO connection system is used on
the bottom of the robot to attach a base. Several
options are available; we were supplied with theG-Base 2.0 (£58), which attaches the arm securely
to the edge of a desk (so long as it’s not too thick).

Robot connections

The MyCobot
280 Pi robot
arm extends to350 mm at fullheight, but canalso tuck up intoa compact ‘ball’78magpi.cc

MyCobot 280 Pi

With the robot arm secured to a desk, it’s time
to power it up. A DC supply connects to a barrel
jack on the base with a red power switch next toit. Raspberry Pi 4’s USB and Ethernet ports are
exposed, along with its GPIO pins via a breakout
header just above. On the opposite side of the baseare a micro-HDMI port, headphone jack, USB-C
port, and microSD card slot.
The inserted microSD card is pre-installed witha special version of Ubuntu MATE featuring abuilt-in development environment for MyCobot
and several apps and tools. An extensive Python
library enables you to quickly start positioning
the arm by setting one or more joint angles orco-ordinates – you can also read the current

REVIEW

With an adaptive
gripper attached to thehead, you can pick up
objects by opening andclosing it
A pen holder accessory
enables the arm todraw shapes andletters on paper

values. So you can manually move the arm into
different positions and read the values to help you
program it to shift between positions.
Another coding option is the myBlockly app inwhich you drag and drop Scratch-style blocks,
including dedicated ones for MyCobot to set joint

A sixth joint rotates theend of the head, to which
you can attach various
accessories using tiny
LEGO connectors
angles/co-ordinates and light up the RGB LED
matrix on the head. Make sure you set the Baudvalue in the init block to 1000000, however,otherwise it won’t move. The arm also works
with the commonly used ROS (Robot OperatingSystem) 1 and 2.
The MyCobot written documentation could beclearer and better organised, but several videos
help you to get to grips with it.

The MyCobot can be programmed with a range of languages– one of the easiest is myBlockly

Attaching accessories

Our MyCobot arm was supplied with a coupleof optional accessories: an adaptive gripper(£106) and a pen holder (£58). The gripper has aconnector that plugs into a servo port on the head.
It worked well and we soon had it picking up anddropping items on the desk with good repeatedpositioning precision.
The head also features a Grove connector,USB-C, and mini GPIO breakout, so there areplenty of connection options. You could even add acamera to give the arm computer vision.
While considerably more expensive than otherRaspberry Pi robot arms we’ve tested, even
without the addition of accessories, the MyCobot
280 is more robust and stylish. It has more
powerful servos, while the joints have bearings forsmoother movement and improved precision.

Verdict
It’s not cheap, but
it does include
a Raspberry Pi 4
and is a robust
and stylish roboticarm with smooth
and accurate
movement.

MyCobot 280 Pi

9/10magpi.cc79