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fsaviator
08-31-2010, 02:24 AM
Has anyone looked at using tilt sensors for axis movements such as yokes.

Dual axis sensors are fairly cheap and one could be mounted in the yoke, thus providing X, Y, and Z input. I guess the issue would be communicating it to FSUIPC or windows.

The benefit would be the ease of installation and interface.

Warren

RobiD
08-31-2010, 05:04 AM
Hi Warren,

Can you put a link to what these look like?

Thanks
David

fsaviator
08-31-2010, 07:57 AM
Here are a few that I found. There are a ton out there, at different price levels.

http://www.leveldevelopments.com/inclinometer-sensors.htm?gclid=CI3ystyG46MCFYxi2godMEf4Rg

These are found in a lot of the newer cell phones (iphone and some that run android) and are the brains behind the bubble level apps and gamepads.

Here's a link to something available at digikey:

http://media.digikey.com/pdf/Data%20Sheets/Sharp%20PDFs/GP1S36J0000F.pdf?cshift_ck=2000132442cs510156840&client_id=5042

These are small enough to mount inside the actual yoke handle, I would think. If it was dual axis, that would be all you need.

jskibo
08-31-2010, 09:58 AM
Wouldn't you need 2 single axis? One to read the shaft movement (pitch) and another mounter in the yoke for roll? Or could you position one on its side in the yoke and get both axis? Just thinking that the off axis reading is +/-45 on these so initial positioning might be critical (mounting vertical might already exceed available reading). Interesting idea!

Leo Bodnar
08-31-2010, 12:05 PM
You will find that most of the sensors are noisy and need correction for drift.

Also it is not trivial [and sometimes impossible] to separate forces caused by acceleration from those caused by gravity.
To have good performance you might need to use directional gyros as well.

737NUT
08-31-2010, 12:30 PM
You will find that most of the sensors are noisy and need correction for drift.

Also it is not trivial [and sometimes impossible] to separate forces caused by acceleration from those caused by gravity.
To have good performance you might need to use directional gyros as well.

If you look at the link he posted it clearly says, integrated signal conditioning and high precision. Your statement is totally incorrect. This option does need some more research! They even have an analog out version. Nice find!

Leo Bodnar
08-31-2010, 12:36 PM
Your statement is totally incorrect.
I apologise, of course you are right. This is the best solution for yoke movement sensing that I have ever seen.

737NUT
08-31-2010, 12:38 PM
This one would work perfect,
http://www.leveldevelopments.com/PDF_Documents/SCA121T.pdf

Notice the .02deg stability, much better than my Saitek yoke!!!!!! LOL

Leo Bodnar
08-31-2010, 03:57 PM
Notice the .02deg stability, much better than my Saitek yoke!!!!!! LOL
Have you noticed cross-axis coupling of 3%?
90 degrees input of roll axis can produce up to 3 degrees contamination input to pitch axis.
Now compare 0.02 deg stability and 3 deg error. I suggest keeping your Saitek at least for now. LOL

jskibo
08-31-2010, 06:09 PM
If you look at the link he posted it clearly says, integrated signal conditioning and high precision. Your statement is totally incorrect. This option does need some more research! They even have an analog out version. Nice find!

LOL, I think you picked the wrong guy to go after for his electronics knowledge :)

Leo Bodnar
08-31-2010, 06:48 PM
It's just a friendly banter :grin: I'm not perfect and always like another point of view.
I had a look at accelerometers and gyros for another project (FFB steering wheel system) few years ago and had to dismiss them in favour of digital encoders however tempting they were...
Analogue output G sensors were too noisy and drifting with time.

fsaviator
08-31-2010, 08:50 PM
Wow,

I never expected such a spirited discussion to stem from my question. There I was messing with my new phone, and playing with the bubble level app that came with it when I thought.... hmmmm.... how does that work?

As I'm getting ready to wire up some pots to my dual yoke setup it struck me that maybe tilt sensors would work.

Maybe down the road...

Warren

Leo Bodnar
09-01-2010, 04:51 AM
...such a spirited discussion to stem from my question. There I was messing with my new phone, and playing with the bubble level app...
:-D Was this intended?
It's a great and workable idea but like any other it has its pros and cons.
E.g. it won't work on a motion platform as expected.
Lots of aircraft have no or very little tilt on controls pitch axis.
However, the sensor is very easy to mount literally anywhere.

Prof Bill
09-01-2010, 11:36 AM
Totally agree with you Leo!
I did a considerable amount of experimentation with quite a selection these devices in the lab and your suggestion is sound advice!

Bill.

Westozy
09-01-2010, 08:11 PM
You just can't beat a pair of plastic gears and an eight buck potentiometer - game over!!!

Gwyn

Shawn
09-15-2010, 05:40 PM
I am planning to build a helicopter cyclic and if I could use a tilt sensor instead of two pots that would simplify things considerably. I was thinking that you could mount the cyclic shaft in a gimbal, extend the shaft below the gimbal and attach a tilt sensor. Could I attach one of these sensors to Leo's BU0836X and calibrate it like a Pot? any recomendations on which sensor would work the best for this application?

maussuam
12-07-2010, 12:35 PM
I am planning to build an Airbus-style sidestick where I use an Arduino board with reed sensors for detecting rotary movements down to 0.1°.
The Sensor is build by Melexis. The also build a three-axis Sensor: Sensor (http://www.melexis.de/Sensor_ICs_Hall_effect/Triaxis_Hall_ICs/Triaxis%E2%84%A2_3D-Joystick_Position_Sensor_648.aspx)
The Arduino application can be found here: Arduino application (http://interface.khm.de/index.php/lab/experiments/rotary-positionsensor-mlx90316/)
Perhaps this is an option...