MobiFlight Community Support

Hi guy,
I wanted to power my trottle with a servo motor.
Flight with the 737 PMDG and I wanted to manage the servo with the Arduino mega 2560.
I wanted to know what is the offest to manage the trottle automatically with Mobiflight?
Thanks for the answers you give me
Paride

Hi Paride,

welcome to MobiFlight!

Before you beginn with the PMDG you need the two main Lists for the Offsets and the EventIDs. The Offset list you find in you FSX-Root-Folder\Modules\FSUIPC Documents\Offset Mapping for PMDG 737NGX.pdf

The EventID-list you can download from here: https://myhomecockpit.de/PMDG_737NGX_EVENT_IDs_SP1d.pdf

Please note: to understand the principle of MobiFlight you should work through the tutorials above. There also is a tutorial to manage a servo.

Tip: do not start with so sophisticated things like a motorized throttle. Start with the simple things to understand the basics.
Tip 2: a servo does not seem suitable for me to drive a motorized throttle. Here you need a stronger stepper motor to cope with the required forces.

If you have further questions don't hezitate to ask them

Hi StephanHo
I have already done several things with Arduino and Mobiflight, for example the flap indicator and all the announcers.
But now I do not know the offset for the trottle .... I know the files you have indicated to me but I do not know what the offset

Thank's

Hi! I have my motorised trottle with the fsuipc offsets. 088C for engine 1 and 0924 for engine 2.

It works perfectly with this offsets for me. I use 2 HITEC hight torque servos due to the heavy forces they should handle.

Hi! I have my motorised trottle with the fsuipc offsets. 088C for engine 1 and 0924 for engine 2.

It works perfectly with this offsets for me. I use 2 HITEC hight torque servos due to the heavy forces they should handle.

Parameters for Mobiflight?
Thank's Francisco

When using Offsets you did not need any parameters.

Offset is an Output from the Simulator which is to be shown as it is (perhaps transformed into BCD o. th. e.)

When using Offsets you did not need any parameters.

Offset is an Output from the Simulator which is to be shown as it is (perhaps transformed into BCD o. th. e.)

Parameters for Mobiflight es:
Value type........
Trasform $
ecc ecc

Not so easy to awnser.....

About basic data please check the Offsetlist yourself... You find the information there....

088C ...Size in Byte 2.... Typ INT Engine 1 Throttle lever, –4096 to +16384
(Programs controlling throttle directly from user inputs should
write to 089A instead if the input should be disconnectable via
offset 310A (e.g. for auto-throttle management)]

About the other settings..... these are individual..... If you place your Servo on the Left or on the right of Throttle you need 100% inverted settings for example.
Also you must know moving angle of your Servo.... You must know if you simulate "reverser" in the Throttle or external.

Here you must know what you like to do..... The user give you the offset.... But the Parameters you must find out yourself based on your planed System and how it should work finaly !

So I have my doubts about whether the servos, even if they are high performance servos, will work satisfactorily.
Not because of the forces to move the levers, but what if the servos themselves do not control, but I manually move the levers and then have to work against the gears of the servos.

On the net, I often read about DC motors with friction clutches, which just do not die from early death as a result of manual movement like the servos.

From model making I know that powerless servo gearboxes do not like it when they are moved without electricity. It works, but the question is, how long.

So much for my knowledge, what I give to concerns. But I also like to teach a better

I have my servos controled by the AT button. You can't move the servos manually if they are powered on, beacause they are holding a position. If you try to force they, maybe bybye gearbox, motor...

To solve the problem, I made a connection using a relay of the servo power supply using the AutoThrottle button.

When the AT is ON, the servos are powered ON, and it works automatically very well, but you can´t force it. If you want to change to manual mode, is as easy as AT/off and the power relay cut the power and they can be moved by hand. I only use manual for taxi and the last 400 feets above ground before touchdown. The 99% of the time in flight they are automatically handled.

I can't remember the AT offset of fsuipc (or if pmdg has its own), but if you assign the value (0/1) to a MF output, you can control a relay with this that make possible the correct function of the motorised throttle.

Good luck!

Clever idea with the relay...

Francisco, have you facebook? o skype
my contact on facebook is : Paride Jabez
my contact on Skype is : Paride 737

Thank,s

Last note.... ( Whatever nobody want hear it )

For a realistic 1:1 System we get in big trouble.....
The System exlaned above ( Servo Control Throttle while AT ON and no manual movement is possible) will work. BUT it´s not realistic!
In a real B737 the Throttle can be controlled at ALL time by the Pilot ( A movement against the working servo will temporary disable the motor..... And if you take your hand of the throttle ( and no force work against the servo) it startup again and do its work.

We talk about that multiple times.... But a solution is not known until now.

A interesting idea from a friend was to implement a Metal band (electrically) through the handle of the Throttle.... So Our Hand will be like a electrical resistor maby....
Important is.... The System must detect that the hand is ON the throttle..... And this input can now controll the Relais that power the Servo ( or not) .

But again there is a little problem..... While Takeoff we hold the throttle until V1 to be able to make a emergency rejected takeoff. If we like to use TOGA for start then our hand must be NOT on the Throttle until it runs from 40% to N1. Else with hand on throttle our new system would prevent the servo to controll it.

****
Maby a additonal Button somewhere in the handle can be the key, too.....
In this option the Throttle is controlled by Servo aslong AT is ON..... But we can disable the Servo temporary with push and hold this button, too ( without disable the AT same time) Technical this button simply CUT the Powerline of Servo aslong it´s pushed.
NOT Realsitic... But maby the most easy solution that alow us controlling while AT ON.

hi sir, what relay type u use. any picture can u upload.

Hi fazli,

if you know the actual current of the servo you only need a relay that can work with this current. A bit can't be wrong.
Take a 5V relay so you can drive it with MF.

Link to relays:
https://www.reichelt.de/Miniaturrelais/HJR4102E-5V/3/index.html?ACTION=3&LA=446&ARTICLE=135737&GROUPID=7620&artnr=HJR4102E+5V&SEARCH=relais%2B5v&trstct=pos_0 3A, 0,69€

https://www.reichelt.de/Miniaturrelais/FIN-36-11-5V/3/index.html?ACTION=3&LA=446&ARTICLE=42373&GROUPID=7620&artnr=FIN+36.11+5V&SEARCH=relais%2B5v&trstct=pos_1 10 A, 1,85€

You can also search for relays for 5V, (your needed) current