Technology and innovation
Small wonder
The compact IRB 120, the most
accurate six-axis robot available,
has amazing flexibility and speed.
Text Nancy Pick Photos ABB
W
hen ABB first began test-
ing the accuracy of its new
compact industrial robot,
the IRB 120, the designers
thought they had a problem.
“When we got the first measure-
ments, we were worried,” said Nicolas
De Keijser, the robot’s product manager.
“It turned out that the robot was so accu-
rate that the measurement system could
not give the right values.” In other words,
the robot was too good to pass the test.
“That has been the story of the IRB
120 all along,” says De Keijser. “The little
robot has been full of surprises.”
In 2007, when the robot model’s de-
sign work first began, ABB intended it for
assembly work in the electronics indus-
try. The idea was to make an affordable
robot suited to low-cost countries where
electronics are typically manufactured.
But the robot has turned out to have
much broader appeal. On sale since
January of 2010, the IRB 120 has al-
ready attracted interest not only from
the electronics industry but also the
pharmaceutical, packaging, food and
beverage, automotive and solar photo-
voltaic industries.
“It’s a practical robot for small, simple
tasks,” says De Keijser. A six-axis robot
— with a jointed arm and wrist — the IRB
120 offers a spherical working envelope.
Its capabilities include placing small tubes
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ABB robotics 2|10
into centrifuges, handling solar cells or
picking up stock cubes and and placing
them in a carton. (Watch the IRB 120 in
action packing stock cubes at www.you-
tube.com/abbrobotics.)
And it’s fast. Using a standard indus-
try test cycle, the IRB 120 can make up to
100 “picks” per minute. “We expect the
IRB 120 to be a great success in pack-
aging applications, primarily because you
get many accurate picks per dollar out of
it,” says De Keijser.
“The IRB 120 has the
best stroke-to-reach
ratio in the business.”
The smaller, the better
In designing the IRB 120, the engineers
focused on one key feature: “We did ev-
erything to make sure that the robot was
as compact as possible,” says De Keijser.
“In every industry floor space is expensive,
so we wanted to keep the robot as close
as possible to the machine it works with.
The robot’s base covers only 18 centime-
ters by 18 centimeters. That’s half a piece
of A4 paper.”
Weighing just 25 kilograms, the robot
has an extremely compact radius when
it moves. In fact, its second axis of mo-
tion has no offset beyond its first axis.
This helps prevent the robot from interfer-
ing with any machine in its working range.
Compactness also offers an advantage
when mounting the robot upside-down, as
it can be installed at a relatively low height,
once again saving space.
At the same time, the robot doesn’t
sacrifice reach. Its “stroke” measures 411
millimeters, which is long compared to its
total reach of 580 millimeters. In fact, De
Keijser says, “The IRB 120 has the best
stroke-to-reach ratio in the business.”
New controller
The robot’s new controller, the IRC5
Compact, was also designed with size in
mind. “We reduced the weight from 150
kilograms to just 27 kilograms,” he says.
They also reduced the controller’s size by
more than 80 percent compared to the
standard model. “Having a small robot
with a large controller didn’t make a lot of
sense, in terms of footprint reduction.”
The entire new system offers unprec-
edented flexibility. The IRB 120 is compat-
ible with ABB’s larger and more versatile
controllers. Over the course of 2010, the
new compact IRC5 controller will gradually
be made compatible with some of ABB’s
larger robots, up to a payload of 8 kilo-
grams — more specifically, the IRB 140,
IRB 1410, IRB 1600, IRB 260 and, last but
not least, the FlexPicker (IRB 360).