How to calibrate symmetrical axes without mechanical center point ?

[SimWare 742]

How to calibrate symmetrical axes without mechanical center point ?

 

In Windows, the X Axis and Y Axis are symmetrical axes.
It means they are intended to be used with controls having left and right distinct ranges
on either side of a center point such as yokes (elevator and ailerons)

When the yoke is release, it automatically comes back to its center point.
Windows then splits the full range in two around the center point.
A left part and a right part.

 

In some systems, the symmetrical X Axis and Y Axis are used for single range controls such as throttle levers.
There is no center point on a throttle lever.

 

When calibrating single range controls connected to X Axis and Y Axis and NOT putting them
at the center point after calibration, wrong behavior occurs like in the video below.

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If you leave the handle full down or full up, the complete resolution will be "assigned" to one half of the course,
and zero to the other half. Hence the jump at 50%.

 

To avoid this, you need to follow the steps below :

 

STEP 1 :
Start the Windows calibration utility for the device you want to calibrate.
(We will use a Honeycomb Bravo Throttle. The two left levers use  the symmetrical X Axis and Y Axis)
Press Next

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STEP 2:
Check the Display raw data box.
Move the levers from min to max position.
Record min and max raw values for the X – Y axes

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Press Next.

STEP 3 :
Substract the min form the max and divide the result by two

Move the levers so that the raw value reading is equal to the above value.
In this example we have both axes ranging from 0 to 1023.
We can use a center point value of (1023 – 0) / 2  = ~512
Press next.

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STEP 4 :

Perform the rest of the calibration as usual, then apply and save the settings.
Check the video hereunder showing the full process :

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STEP 5 :
If you are using Microsoft Flight Simulator, make sure the sensitivity and reactivity curves are set to linear :