Setting and reading nosewheel position

[Flygard]

Hi,

I'm a little new to the P3D/Prosim/FSUIPC world, so apologies in advance for use of wrong terminology or misunderstandings.

I'm making a motorised, force-feedback tiller for the 737 (Prosim's model). To make it work I need to both set and read the nosewheel position.

The former seems straight forward, but the latter makes me scratch my head. 🤔

So the first question is if it's possible to read the actual nosewheel position. This is important because I use the difference in tiller position and actual nosewheel position to increase force feedback (the bigger the difference the harder the force feedback, with ff increasing exponentially).

I'm using Arduino and prefer interfacing over network/IP. FSUIPC6 and latest versions of P3D and Prosim.

Any tips? 😀

 

 

 

[John Dowson]

On 12/25/2020 at 8:38 PM, Flygard said:

So the first question is if it's possible to read the actual nosewheel position.

I'm not sure it is. What are you using to set the position?

There is an indexed simvar GEAR STEER ANGLE that I could add, with indices for centre, left, right and aux (and also individual variables for each), but I'm not sure if this is what you are after or if this would be populated when using ProSim. Do you want me to add these to see if they can be of use?

John

[Flygard]

On 12/29/2020 at 12:08 PM, John Dowson said:

I'm not sure it is. What are you using to set the position?

Nothing at the moment, to be honest. Whilst I (mostly) have the prototype hardware ready and working, I'm still investigating the best approach in terms of integrating it with the sim. I was under the impression that I could do this using FSUIPC as well?

I was basically planning to integrate the "setting" part the same way everyone else does with their tillers. However since I'm using Arduino AND (preferably) want to do it over the network rather than USB I'll probably run into a bunch of issues. 😁

Quote

There is an indexed simvar GEAR STEER ANGLE that I could add, with indices for centre, left, right and aux (and also individual variables for each), but I'm not sure if this is what you are after or if this would be populated when using ProSim. Do you want me to add these to see if they can be of use?

Thanks for offering to add that. That sounds like exactly the thing I'm looking for. Like you, I'm unsure whether Prosim populates that. Would there be an easy way for me to test it before bothering you with adding something which might not ever be used?

Apologies again if I'm asking n00b questions here - I come from the X-Plane world where things are done a little (a lot) differently. Literally starting experimenting with P3D/Prosim/FSUIPC a few weeks ago and learning curve for hardware integration seems to be rather steep!

Happy new year!

 

 

 

[John Dowson]

12 hours ago, Flygard said:

Thanks for offering to add that. That sounds like exactly the thing I'm looking for. Like you, I'm unsure whether Prosim populates that. Would there be an easy way for me to test it before bothering you with adding something which might not ever be used?

Its pretty simple to add. I'm not familiar with ProSim, so I don't know if it will be populated. I'll make a test version for you in the next few days so that you can test.

John

[John Dowson]

@Flygard Could you try the attached version please. I have added GEAR CENTER STEER ANGLE only for the time being, at offset 0x0BF8 as a 4 byte float (F32).
Its a 'percent over 100' value, so should give values between +1 and -1, although during a quick test I have seen values between -1.35 and + 1.3 and I'm not sure why.
If the values where between +1 and -1, I could convert them to an integer in the -16383 to +16383 range (and reduce to a 2-byte int), but as I get values outside of this range I've just left the raw value for now.

FSUIPC6.dll

John

[John Dowson]

Btw, I have noticed that offset 0x0BF8 is already reserved for 'Unlimited visibility value', so in the next release I have moved this value to offset 0x0C10. You can still test with the dll posted above in the original offset position.

John

[John Dowson]

Maybe @Thomas Richter can explain why this value isn't in the -1 to +1 range, or what the actual complete range is so, that I can calibrate to an integer  range of -16383 to +16383?

[Flygard]

Excellent. Thanks very much. I will be working on this project early next week so will report back as soon as I've got some test results.

[Flygard]

Sorry about the delayed response - seems to be working perfectly! Thank you very much.

I'm seeing very precise values (1.08132562, for instance) up to +/- ~1.35. No big problem for me personally - I need to do scale conversions anyway and will use a sensible max value.

By the way: It has always puzzled me why I can't move the nosewheel when the plane stands still. But I guess that's a P3D thing.

Thanks again!

Edited January 19, 2021 by Flygard
Tagged the wrong guy.

[John Dowson]

14 minutes ago, Flygard said:

Sorry about the delayed response - seems to be working perfectly! Thank you very much.

No problem, thanks for reporting back.

14 minutes ago, Flygard said:

By the way: It has always puzzled me why I can't move the nosewheel when the plane stands still. But I guess that's a P3D thing.

Maybe. But if you are using FSUIPCs blending facilities, it could be due to the RudderBlendLowest parameter having the default value of 1 knot, so for speeds below this the rudder only is used (for rudder operation checks). You could maybe try adding this and setting to 0. See the Advanced User guide for details.

John