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Mechanical Technology — February 2015
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Innovative engineering
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W
inkel’s company name,
while chosen to combine
the words “industrial” and
“radar”, also borrows its
meaning from the latin word ‘indurare’:
to make hard or to improve, a name
that came to him during his years as a
student. He explains: “I was trained as
a mining engineer. During my internship
years, I spent several years studying dif-
ferent mining operations: at Codelco’s
copper mines in Chile; the Goonyella
underground coal mines in Australia; and
at lignite mines in Germany.
“I noticed that on big expensive min-
ing machines, almost no information
was being made available to operators.
When you buy a modern car, you get an
automatic park assist system based on a
proximity sensor to help you position your
car safely. But on R500-million bucket
wheel excavators there are seldom any
operator-assist features incorporated into
the design. This, I couldn’t understand,”
he tells
MechTech
.
“At that time, when we asked OEMs
such as Liebherr and Caterpillar about
helping the operator to look after these
machines, the answer that came back
was always that the sensor electronics
available on the market wasn’t reliable
enough for the rough mining environment
and that the market could not justify de-
velopment investment,” Winkel explains.
Based on these observations, research
and development towards a monitoring
system suitable for these environments
began in 2003 at Aachen University in
partnership with Ulm University’s Radar
Centre of Excellence. “Initially, we tried to
use laser technology, but lasers are opti-
cal devices that work for one day, then
the next day they get dirty and are unreli-
able. So we quickly switched to radar.”
The feasibility of radar technology was
originally demonstrated in 1904 by the
German inventor Christian Hülsmeyer,
who used radio waves to detect the pres-
ence of ships in dense fog. Describing
the benefits of using radio waves as
opposed to laser light, Winkel points
towards an image showing the effects of
dust particles on transmitted laser and
radar waves. “The wavelength of a laser
beam is around 1.0
µ
m, which means
that the beam will be fully reflected by a
dust particle with a diameter of 2.0
µ
m.
This prevents laser-based systems from
detecting objects behind a dust or fog
curtain. Radar operates on much longer
wavelengths of around 4.0 mm, resulting
in considerably better penetration into fog
or airborne dust,” he says.
Early investigations into the avail-
ability of radar sensors for mining and
materials handling equipment revealed
that only one-dimensional (1D) level de-
tectors were available, which were “never
going to give us enough information to
control machines in industrial and mining
environments,” he suggests.
Reik Winkel (left), executive director of indurad, an
industrial automation solutions company founded
in Germany in 2008, talks to
MechTech
about the
safety and productivity advantages of protecting and
optimising expensive materials handling equipment with
radar-based monitoring, operator assistance, collision
avoidance and automation solutions.
The transfer and hopper cars of a bucket
wheel excavator were automated at this coal
mine near Aachen. In this application, the
loading unit and the transfer car were auto-
mated to follow the bucket wheel excavator
along the length of the bench conveyor.
Inset:
A rendered image showing the radar
sensing used to keep the transfer and hop-
per cars at the required relative speed and
position.
1. With ThyssenKrupp, indurad’s iCrusher
solution was used on a fully mobile crushing
systems in China. The quantity and size of
material along the full length of the apron
feeder is monitored to ensure that the
crusher is never empty.
2. An iBelt solution fitted with iDVR belt
speed radar (blue), iDRR profile radar (red)
and iLDR alignment radar (green). As well as
proactively checking belt alignment and slip,
this combination allows the material travel
speed to be calculated in real time, which
can be converted into an instantaneous
volumetric flow rate. By taking successive
readings, very accurate throughput data can
be accumulated.
3. Winkel suggests that the use of indurad
radar systems for 3D stockpile management
and reclaimer productivity enhancement can
improve stockyard productivity by between
5.0 and 10%.
Industrial radar and rough
materials handling
The Aachen-based research efforts led
to the development of a range of robust
and accurate radar sensors, with 1D, 2D
and 3D capability, and priced between
the very sophisticated ‘Milspec’ radar
detection systems, costing hundreds of
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