MobiFlight Community Support

hi, everybody ..
any tip and trick setup servo gauge pmdg ngx
1.min ?
2.max?
3.%?
4.how tu apply enterpolition current value?
5,about configure output?

#finish Efis & mcp panel. i am happy. now next project mip panel

Sorry i have no guide for you.... I Also have no finished MCC File at the moment for this ... ( I Build it 1 year ago for testing but forgot to save it)

Basicly it´s easy.....

Offset is from 0 - 40 ..... To Prevent Jumps and run it smoothe you neet to Transform the value first by 100 ($*100)
Cause Mobiflight only see full Numbers.... 0,01 - 0,99 all is shown as "0" .... 1,01 - 1,99 is hown as "1"
So Running Flaps from 0-1 or 1-2 will occure in a Jump at the end.... With Multiply it run from 0-100 instead of 0-1 in a smoothe kind.

Then you need Interpolation cause Flaps Gauge is NOT Linear....

(Also Note this Gauge have a range more then 180° So you need a Servo with more then 180°, too.... Or with a cogweel system. I Personal will prefer a Stepper Motor here ! )

Summary... with Interpolation you need to define all Points in the Gauge..... So Offset Value 1 ( or better 100 if you use multiply from above) will result in a OUTPUT Value that is correctly in the "Flap 1" Position of your self build Gauge !

PLEASE: Research this Forum..... There are lots of Threads about building Servo or Stepper Gauges with Non-Linear System like this !

tq your advice.
i have many lot step motor. but 12v.
1-can i used steppermotor12v. or any suggestion power supply.
2-my servo tower pro limit degree. cant rotate 180.i try diy my servo to 360'.can i use servo that

Hi fazli,

it shoult not be possible to use a 12V stepper instead of a 5V stepper. Also not if the 12V stepper is driven with an external power supply.

If you use a 12V stepper the signals need to be also 12V. If you use the 5V signals they a not big enough to drive the stepper. The amplitude is less than half of the stepper voltage an therfore only below the threashold of recognizing a high-level-signal.

A 5V stepper motor with ULN2003 driver-board costs only 5 Euro and guaranteed a smooth runnung of the needle.
First I have used a servo which runs very restless, the needle also. So I tried the stepper.

Please note when using a stepper: you can not influence the holding current. this current is about 170-190 mA durable. So it is recommended to use an external power supply to spare the MEGA. Only Vcc and GND to the stepper (from external power supply) and GND of external power supply to MEGA an the signal wires to ULN2003.

If you rebuild the servo you can use it safely. For the above reasons, but I would advise against the servo

If a Servo with 12v can be used i don´t know.... But Stephan think NO.... so i will agree with him ( he is the electronic specialist)

About the DIY part....
Changing a Motor from example 180° to 360° is no problem..... You only need to build a cogwheel system.
Servo got 180° Target Gauge need 360° so you got a resolution of 1:2 ...... That Mean you need a Cogwheel of 2:1
For example a wheel with 20 tooths on Servo and a 10 toohts wheel on Gauge will work.....
A Turn of 20 tooth wheel will turn the other 2 times ( 20-10 = 2-1 = 1 Turn-2 Turn )

BUT NOTE: with a 2 wheel system the direction of second axis is inverted ! So it turns now counterclockwise !

To solve this you got 3 ways....

1. Software rebuild
Simply change the interpolation values.... So Flaps 0 now is Highest position and Flaps 40 is lowest..... Only Optical issue now is in powerless status your gauge will show Flaps 40 .... But after Mobiflight start the needle will go to 0 correctly

2. Mount the Motor from Other side
Thats the easyest solution .... If you have space nearby the gauge simply mount the Motor inverted on the cogwheel

3. Use a 3.rd Cogwheel with same tooth count like 2nd wheel.... Then it´s a 1:1 resolution and not change Degrees range.... But inverted dierection again,
So for example 20-10-10 will work here !

********
Last Note: As Stephan said i would recommend a Stepper Motor with ULN2003 Board, too. Costs maby 2-5 $ and workes perfect in that situation without difficult problems!