Trim Wheel Interfacing (Jeehell FMGS)

** Jeehell FMGS version 59.0 and above includes a native Phidget Trim wheel driver. Install the FDS trim wheel driver with Jeehell FMGS and this will allow you to assign the different trim values on the software interface.

The Airbus trim wheel can be interfaced directly with Jeehell FMGS using the Sidentus Trade & Technology GmbH FDSMotorTrimWheelCtr software.

Requirements – Jeehell FMGS, PhidgetMotorControl HC, FSUIPC (registered), potentiometer (joystick) I/O, Phidget21 Libraries

First ensure the trim has been mechanically setup correctly. A DC motor attached to a clutch and gears connected to a potentiometer drives the system.

Interfacing Steps

Install the Phidget21 Control Panel and ensure the WebService is running.
Connect the trim mechanism potentiometer to a joystick interface board (Leo Bodnar, Arduino Leonardo, etc)
Connect the DC motor power supply to the PhidgetMotorControl board
Open FSUIPC (Under Add-ons menu, Prepar3d)
Click on the Axis Assignment tab
Move the trim wheel, FSUIPC should detect the axis
Assign an Offset Word Set (in this example x5530 is used)

Next use the external program DIView or FSUIPC to scale the range of the pot between -12000 to +12000 (the program will disconnect the trim wheel after > +12000) ; for example adding *0.5 to the axes configuration in FSUIPC6.ini file

[Axes]
PollInterval=10
RangeRepeatRate=10
0=5X,152,F,x02005530,0,0,0,*0.5 -{ FSUIPC: offset word set, offset 5530 }-

Open the FDSTrimWheel.ini file and edit as appropriate

[common]
TrimToZeroAfterTouchdown=off // Turn this setting off as Jeehell FMGS automatically trims to zero
TrimWheelUpdateRunningAtStart=on // Turning this on will connect the software automatically to the trim wheel on program start
FsuipcConnectOnStart=on
[fsuipc]
WriteTrimWheelPositionToJeehell=on
GetTrimWheelPositionFromJeehell=on
TrimWheelAxisFsuipcOffset=5530 // Use a custom unused offset, the same offset assigned in FSUIPC)
[phidget motor controller]
EmergencyMinPos=-5400
EmergencyMaxPos=8300 // Minimum and maximum axis range (disconnects from trim wheel)
MaxBwdPos=-5300
MaxFwdPos=8200 // Minimum and maximum axis range when trim is set to 4DN and 14UP
TrimWheelHysteresis=40 // Trim sensitivity; higher values provides a larger 'null zone' value
gain=0.05 // Either positive or negative value, ** decimal or comma (language/country dependent)
maxVelocityABS=13
minVelocity=8 // Set the acceleration values by changing the velocity
CtrBoardPortNo=5001
ServerIPAdress=192.168.1.150 // Set this to the Phidget WebService IP Address
localAccess=off
[scaling]
MaxScalingPoints=22
ScalingPoint_21_WheelPositionValue=8200 // To determine the position open the trim interface program and record down the Received Trim Wheel Axis Position for each trim value
ScalingPoint_21_TrimValue=17 //TrimValue represents the actual aircraft trim which will be set by Jeehell FMGS
ScalingPoint_20_WheelPositionValue=-5300
ScalingPoint_20_TrimValue=-17
ScalingPoint_19_WheelPositionValue=-5149
ScalingPoint_19_TrimValue=-4
ScalingPoint_18_WheelPositionValue=-4360
ScalingPoint_18_TrimValue=-3
ScalingPoint_17_WheelPositionValue=-3627
ScalingPoint_17_TrimValue=-2
ScalingPoint_16_WheelPositionValue=-2843
ScalingPoint_16_TrimValue=-1
ScalingPoint_15_WheelPositionValue=-2458
ScalingPoint_15_TrimValue=-0.5 // Trim 0.5DN, ** decimal or comma (language/country dependent)
ScalingPoint_14_WheelPositionValue=8167
ScalingPoint_14_TrimValue=14
ScalingPoint_13_WheelPositionValue=7779
ScalingPoint_13_TrimValue=13
ScalingPoint_12_WheelPositionValue=6987
ScalingPoint_12_TrimValue=12
ScalingPoint_11_WheelPositionValue=6203
ScalingPoint_11_TrimValue=11
ScalingPoint_10_WheelPositionValue=5479
ScalingPoint_10_TrimValue=10
ScalingPoint_9_WheelPositionValue=4767
ScalingPoint_9_TrimValue=9
ScalingPoint_8_WheelPositionValue=3968
ScalingPoint_8_TrimValue=8
ScalingPoint_7_WheelPositionValue=3252
ScalingPoint_7_TrimValue=7
ScalingPoint_6_WheelPositionValue=2480
ScalingPoint_6_TrimValue=6
ScalingPoint_5_WheelPositionValue=1696
ScalingPoint_5_TrimValue=5
ScalingPoint_4_WheelPositionValue=956
ScalingPoint_4_TrimValue=4
ScalingPoint_3_WheelPositionValue=224
ScalingPoint_3_TrimValue=3
ScalingPoint_2_WheelPositionValue=-556
ScalingPoint_2_TrimValue=2
ScalingPoint_1_WheelPositionValue=-1269
ScalingPoint_1_TrimValue=1
ScalingPoint_0_WheelPositionValue=-2066
ScalingPoint_0_TrimValue=0

FDSMotorTrimWheelCtr Software – Jeehell FMGS sets the Trim Wheel Axis Position via FSUIPC

If your motor is noisy you can install noise reduction foam or ceramic capacitors.

Thank you to Sildetus for the software development. You can visit their professional motion flight simulator at:

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  1. Pingback: Trim Wheel Motorization | Soarbywire

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