DIY C-130 Flight Sim Yoke: How to Information?

[BoydBoy_Aero 0]

I am trying to convert an actual C-130 yoke to be used for flight controls on our flight simulator.  I have no prior experience with this type of project and was wondering if I could obtain some advice on hardware and control setup. And/or, are there detailed guides available to conduct this type of modification? An example is the use of potentiometers to create the roll, and pitch inputs by movement of the flight yoke and stick. It is a flight control that pivots at a single point near the floor having a throttle arc, while the yoke rotates on a perpendicular axis to the pilot torso at the top of the control stick. I have read some sites recommend using 100k ohm rotary potentiometers with a "linear taper". Does this sound reasonable? Also, how would I ultimately translate the mechanical input into a digital single that can be read using a USB plugin?  Any help and guidance on this is much appreciated. Please feel free to ask any questions.

[MartinRex007 390]

Might also want to post your request here:

https://www.avsim.com/forums/forum/110-home-cockpit-builders/

 

Cheers

Martin

[ark 1,288]

BoydBoy_Aero,

What you need is an analog to digital board (A/D board) to convert the analog voltages from your pitch and roll potentiometers to digital USB signals. See the thread at the link below. This thread and video  deals with a Saitek yoke, but the point is it shows how to use the Leo Bodnar BU0836A joystick board ( an A/D board that outputs USB signals) to convert the voltages from the pitch and roll potentiometers used in the Saitek yoke to USB. So you would just need to substitute your potentiometers for the Saitek ones.

Al

https://www.avsim.com/forums/topic/497986-saitek-pro-flight-yoke-dead-zones-fix-video/

Edited July 12, 2018 by ark

[oemlegoem 29]

Use the Leo Bodnar BU0836A board. It is very easy.
http://www.leobodnar.com/shop/index.php?main_page=product_info&cPath=94&products_id=204&zenid=71abc2234223ffc4b7b6b4471daf65ac

The standard recommendation with this board is to use a 10kOhm potentiometer. Use a linear potentiometer. In order to get the highest amount of resolution from the BU0836A, choose a potentiometer with a rotation range closest to what you need. Example: if you need 30degrees, and the potentiometer has 300degrees, then you use only 1/10 of the resolution of the 12bit 4096step controller. That is 409 steps. Not bad, but a potentiometer with less rotation would have higher resolution, more steps.
There are different materials used inside the potentiometer: carbon, cermet, conductive plastic. Avoid carbon, I would prefer conductive plastic.
There is a large range in quality. Check expected life in the datasheet.  

If you want to increase quality: use a hall position sensor. Hall sensors have longer life because no sliding contacts are used.
http://www.ttelectronics.com/sensors/rotary-position-sensors-magnetic-hall-effect/single-turn-non-contacting-hall-effect-position-sensors  
Or this as an alternative
https://www.bourns.com/docs/product-datasheets/ams22b.pdf
With these hall sensors, also choose a degree of rotation close to what you need.

[BoydBoy_Aero 0]

On ‎7‎/‎12‎/‎2018 at 3:39 AM, oemlegoem said:

Use the Leo Bodnar BU0836A board. It is very easy.
http://www.leobodnar.com/shop/index.php?main_page=product_info&cPath=94&products_id=204&zenid=71abc2234223ffc4b7b6b4471daf65ac

The standard recommendation with this board is to use a 10kOhm potentiometer. Use a linear potentiometer. In order to get the highest amount of resolution from the BU0836A, choose a potentiometer with a rotation range closest to what you need. Example: if you need 30degrees, and the potentiometer has 300degrees, then you use only 1/10 of the resolution of the 12bit 4096step controller. That is 409 steps. Not bad, but a potentiometer with less rotation would have higher resolution, more steps.
There are different materials used inside the potentiometer: carbon, cermet, conductive plastic. Avoid carbon, I would prefer conductive plastic.
There is a large range in quality. Check expected life in the datasheet.  

If you want to increase quality: use a hall position sensor. Hall sensors have longer life because no sliding contacts are used.
http://www.ttelectronics.com/sensors/rotary-position-sensors-magnetic-hall-effect/single-turn-non-contacting-hall-effect-position-sensors  
Or this as an alternative
https://www.bourns.com/docs/product-datasheets/ams22b.pdf
With these hall sensors, also choose a degree of rotation close to what you need.

I took the back cover case off of the top portion of the flight control shaft. It exposed a cable driven assembly with the rotational input from the yoke turning a gear with the same fixed rotational axis. This gear is linked to a chain which provides the overall rotational input to the cables connected to flight control surfaces.  The gear teeth has a gap of approximately 1/4" between each tooth and a depth of approximately 1/2".

Would the hall sensors be an effective way to measure to roll input if it would be used to sense the rotation of the gear? Is there a particular one you would recommend to use? I have not messed with hall sensors before, but have heard they are very accurate.