Stepper Motor - which drvier?

Support for Arduino in combination with Air Manager and Air Player

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marcel_felde
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Re: Stepper Motor - which drvier?

#11 Post by marcel_felde »

I have never had any issue with #smooth movement# at all - what do you normally use ? it will be the software, not the stepper or driver that is causing an issue.
I used ArdsimX. A X-Plane plugin to drive steppers directly connected via Arduino-Boards. This plugin was also able to use the Propwash-Board. So you only need 1/4 of the pins on the Arduino.
ArdsimX became SimVim and the movement of the stepper needles was super smooth. But as mentioned you could only use one Arduino Uno for I/O. That is enough for the Steppers in a 737NG or A320, but not a GA airplane with steam gauges.
So I did never use this in my simulator. I did support this development for some years but could never use it. Today it is named Realsimcontrol.

marcel_felde
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Re: Stepper Motor - which drvier?

#12 Post by marcel_felde »

I would be interested in seeing any info you have on your optical calibration. Do you have one built you can take an image of please ?
NG Gauge.jpg
The yellow are is where IR sensors sit in. The orange are is a stripe that uses reflective material. Whenever the stripe passes the sensor, there is a signal to Air Manager. Like a button press. And the code then sets a certain value to this position.
This is all pretty tiny for the small needles in a NG gauge.

This is the cockpit. You will see, that you need much more than one Arduino UNO pins for the gauges. :D
https://www.instagram.com/p/CKzyV-ehoDo ... _copy_link

And here you can see the needles in action:
https://www.instagram.com/reel/CgUOuSPA ... _copy_link
If you pay attention, you will see that they do not run perfectly smooth. This video is still with ArdsimX under the hood.

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jph
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Re: Stepper Motor - which drvier?

#13 Post by jph »

Very impressive work and yes, that is the smoothness I would expect.
You simply cannot beat steam gauges in GA. As soon as you put in a G1000 then you might as well be flying anything. No character at all imo.
I am impressed with your sensors for the x27.
Are you 3d printing the housing ?
Have you one there you could actually photograph ?

You have no such limitations as one arduino :D. Where are you seeing lack of smooth movement ? using what program ?

Also in air manager, you can make virtually any custom add on you require with hardware. If you can program with the Arduino you can also use anything custom such as the amazing 'accelstepper' library. You can create custom hardware from virtually anything programmable in Arduino to Air Manager as AM provides an Arduino library called 'messageport' - not that you would need to in this case.
Joe. CISSP, MSc.

marcel_felde
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Re: Stepper Motor - which drvier?

#14 Post by marcel_felde »

photo_2022-08-22_21-09-57.jpg
The original scale with geared needles.
photo_2022-08-22_21-09-37 (2).jpg
My 3d print without the sensor.
photo_2022-08-22_21-09-37.jpg
Prototype with hot glued sensor.

marcel_felde
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Re: Stepper Motor - which drvier?

#15 Post by marcel_felde »

Where are you seeing lack of smooth movement ? using what program ?
As mentioned with ArdsimX. They were much smoother with SimVim. Not yet tried to use Air Manager directly except some testing purposes.
Problem is, that they have a very fine but visible stuttering at some rotation speeds.

I have the original motors of the (real aviation) gauges here, but do not know how to drive them. ;)

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Ralph
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Re: Stepper Motor - which drvier?

#16 Post by Ralph »

Curious to see what they would do with AM... Is it possible to try?

marcel_felde
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Re: Stepper Motor - which drvier?

#17 Post by marcel_felde »

Ralph wrote: Mon Aug 22, 2022 8:55 pm Curious to see what they would do with AM... Is it possible to try?
What do you mean with "they*"?

Had some wall restorations here at my workshop so things are still quite chaotic. ;) But could try...

* X27 Steppers, Stepper-Driver-Boards...

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jph
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Re: Stepper Motor - which drvier?

#18 Post by jph »

Thanks for the images. Very neat.
I have used the stop limit peg on the internal drive gear in the past (with the case stop area removed) and it also works very well also. Very fiddly to mount though. It used SMD tx/rx and a dab of hot glue.
One day I will get around to looking at it again. It is good to get black x27 gauge units if going this route although not too critical.
The movement issues you talk about are almost certainly down to coding. It is a very interesting challenge to code for rotary movement and simulate real world.
It needs an acceleration figure or a means of automatically calculating the delta - in this context used as meaning 'rate of change' of velocity.
I am not familiar with any of the programs you mentioned as they hold no interest for me due to their limitations but there will definitely be good and bad solutions.
If you imagine a gauge where a 'speed of rotation' is set then, if that figure is fixed and depending on the update speed you will never get a smooth gauge as a slowly moving gauge will micro jump from one position to the next. A good gauge to test the code on is always the altimeter during a stall / recovery. ASI is another where the actions should be totally fluid and damped.
If you use Arduino IDE then look at a lib called accelstepper and their example codes. The movement is so fluid and the options are simply amazing.
One day I will write a messageport stepper control for AM using that lib using a PICO. There is a bug with AM and the VCP drivers at the moment but there is hack workaround to open the com ports first with ANY other program then AM works fine. - anyway, that's for another day.
A single board driving 40 steppers would be really cheap to build (cheaper than the propwash board !)
Really nice sim. A credit to you.
Joe. CISSP, MSc.

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jph
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Re: Stepper Motor - which drvier?

#19 Post by jph »

Oh, yes, you mentioned the original drive units. I could tell (hopefully) if you post an image or two but they are most likely sin/cos drive. A little like the old resolver units.
There are IC's that can be used but it would be a complete diy solution and down and dirty with the soldering stick ;)
This datasheet gives some basic sin cos inductive transducer info.
https://www.nxp.com/docs/en/application-note/AN1942.pdf
Joe. CISSP, MSc.

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Ralph
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Re: Stepper Motor - which drvier?

#20 Post by Ralph »

marcel_felde wrote: Tue Aug 23, 2022 3:27 am What do you mean with "they*"?
The stepper motors that run not so smooth with Ardsim, or was it Simvim? Anyway :) I'm curious if they run smooth with Air Manager.

Do you have the small geared needle as well in your design?

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