Feature: Laser triangulation sensors
Laser triangulation sensors measure lateral position of rail bogie wheels
The optoNCDT 1420 laser triangulation displacement sensor measures the lateral position of the bogie wheels relative to the railhead
L
aser triangulation sensors from Micro-Epsilon are being used to measure the lateral position of rail bogie wheels relative to the railhead in a rail traction technology project by SET Limited.
issues. What we want to do is to see this
“Actively yawing the wheels along with
technology implemented as the technolo-
active torque control manages the con-
gy of choice for rail passenger vehicles of
tact patch at the optimum point of the
the future.”
rail, practically eliminating RCF. This is because ideal [close to radial] steering
In the ActiWheel solution, the motor is inte-
reduces the energy in the contact patch
grated into the wheel, which means there
to a point where RCF does not occur
is no transmission between the two and
and wear is very small.”
ActiWheel is a traction system that uses ar-
no moving parts beyond a bearing which
tificial intelligence to guide trains along the
every wheel and axle has. In addition, there
tracks – enabling quicker, smoother and
are no friction braking systems, so there
Reliable, durable and lightweight
more economical rail travel. The solution
would be a significant reduction in the
The ActiWheel is a high-reliability, du-
could dramatically change the way that rail
amount of maintenance required.
rable system and Cooney expects his
vehicles run on the railway. As Martin Whit-
wheels to last somewhere between four
ley, Director at SET Limited, explains,“This
Neil Cooney, Technical Director at SET
to 10 times longer than a conventional
revolutionary wheel motor can be con-
Limited, comments, “One of the biggest is-
set-up. There is virtually no wear, which
trolled to produce more driving force on
sues facing the rail infrastructure is Rolling
means the rail isn’t being damaged and
one side or the other in order to steer the
Contact Fatigue [RCF], which occurs due
the wheels don’t deteriorate. The solu-
wheelset down the centreline of the track.
to the energy in the contact between the
tion is also lightweight, which means it’s
For the last 200 years, conventional rail ve-
wheel and the rail. Conditions under the
a lot easier to accelerate and decelerate
hicles have only had a solid axle and wheel
contact patch are always severe and the
the train and there is additional carrying
coning providing this capability, which
yield stress of the rail wheel is always ex-
capacity for passengers.
drives some significant compromises and
ceeded, on at least a microscale.
26 dpaonthenet.net
