SENSORS | RAIL
KTEHEINPIGNSG TORNACK Laser triangulation sensors are being
used to measure the lateral position
of rail bogie wheels relative to the
rail head in a ground-breaking rail
traction technology project.
ActiWheel is an innovative
traction system from
Micro-Epsilon that uses
arti cial intelligence
to guide trains along the tracks,
enabling quicker, smoother and
more economical rail travel. The
solution could dramatically change
the way that rail vehicles run on the
railway.
Martin Whitley, director at
Derby-based SET Limited explains:
“This revolutionary wheel motor
can be controlled to produce more
driving force on one side or the
other in order to steer the wheelset
down the centreline of the track.
For the last 200 years, conventional
rail vehicles have only had a solid
axle and wheel coning providing
this capability which drives some
signi cant compromises and
issues. What we want to do is to
see this technology implemented
as the technology of choice for rail
passenger vehicles of the future.”
In the ActiWheel solution,
the motor is integrated in the
wheel, which means there is no
transmission between the two and
no moving parts beyond a
bearing which every wheel
and axle has. In addition,
there is no friction
braking systems, so there
would be a signi cant
reduction in the amount of
maintenance required.
Neil Cooney,
biggest issues facing
the rail infrastructure
is Rolling Contact Fatigue
(RCF), which occurs due
to the energy in the
contact between the
wheel and the rail”
technical director at SET
Limited adds: “One of the
biggest issues facing the rail
infrastructure is Rolling Contact
Fatigue (RCF), which occurs due to
the energy in the contact between
the wheel and the rail. Conditions
under the contact patch are always
severe and the yield stress of the
rail wheel is always exceeded, on
at least a microscale.
“Actively yawing the wheels
along with active torque control,
manages the contact patch at
the optimum point of the rail,
practically eliminating RCF. This
is because ideal – close to radial –
steering reduces the energy in the
contact patch to a point where RCF
does not occur and wear is very
small.”
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REALNIDA BLLIGEH, DTUWREAIGBHLET
The ActiWheel is a high
reliability, durable
system and Cooney
expects the wheels
to last somewhere
between four to 10 times
longer than a conventional
set up. There is virtually
no wear, which means the
rail isn’t being damaged and
the wheels don’t deteriorate. The
solution is also lightweight, which
means it’s a lot easier to accelerate
and decelerate the train and there
is additional carrying capacity for
passengers.
For the last nine months,
ActiWheel has been put through its
paces in a technical demonstrator
project. An ex-London Underground
train with a single carriage was
tted with an ActiWheel system on
each of its eight wheels. The project
was a success, says Cooney, with
the results proving that wear and
RCF were almost negligible. The
project has already received some
signi cant industry interest and
“One of the
32 WWW.EUREKAMAGAZINE.CO.UK | MAY 2020
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