Increasing sensitivity of joystick pot

[CptTangerine]

Hi

 

 

 

I have converted an X-45 stick into a helicopter flight system and one of the things that I have done is to extend the joystick handle shaft by about 2'. The practical upshot of this is that I am not moving the handle in much smaller circles than would normally be the case and I have had to increase the sensitivity in-game to take this into account.

 

 

 

I would like to alter the stick so that it is more sensitive mechanically / electronically so that I don't have to up the sensitivity in-game. The problem is that using the in-game calibration to increase the sensitivity also amplifies the noise in the pot.

 

 

 

I have been working on using gears to mechanically amplify the movement of the stick but it occurred to me that there might be a better way, swapping out the pots.

 

 

The pot that is in the stick is a B50K-65 and I am assuming, from Googling around, that the 50K is the resistance in the pot. So, the question I have is, could I increase the sensitivity of the stick by putting in a different pot with a different resistance, and would this be a good way of doing things?

 

 

Thanks!

 

 

CptT

[Ranma13]

The issue is that you're not using the entire travel of the pot, and you're using only a small portion of it and extrapolating it to a full range. All pots have some inherent jitter to them, and increasing the sensitivity will also increase the jitter. You could replace it with a more expensive pot, but it's best to try and find one that covers your new angle of travel instead of using only 30 degrees on a 150-degree pot.

[CptTangerine]

So, it would be the degree of travel rather than the resistance that I would need to look for?

 

 

Thanks.

 

 

CptT

[Ranma13]

Yes, the degree of travel. Potentiometers are voltage dividers, they take an input voltage and give you a value between 0-100% of that input voltage. The resistance is only to limit the current running through it so that you don't suck up too much power. This doesn't matter too much for USB devices, so just try to match the 50K resistance. Theoretically 10K would be better because the higher the resistance, the more subject it is to circuitry noise, but it might not be a good idea to suddenly increase the current draw by 5 times if you're not sure the circuit board can take it.

[CptTangerine]

Hi

 

 

 

Thanks for that. I am going to persist with a mechanical solution for the moment. I have just tried recalibrating the stick with a smaller circle and this seems to work quite well. Increasing the sensitivity in calibration and decreasing the sensitivity in-game seems to dampen a lot of the noise in the pot.

 

 

Cheers!

 

 

CptT

[BlacleyCole]

Pots are variable resisters and fall under ohms law which I’ll have to review to be exact but resistance and voltage are two of the three factors involved. As onegoes up the other is decreased. So what you are doing by increasing the sensitivity in software is actually amplifying the results of the pot. So along with the increased value comes the increase noise. Like was said above pots are very noisy

[CptTangerine]

I understand that, but what I think was happening before was that I was basically amplifying the noise twice, whereas now, I'm effectively amplifying the noise at source and then damping it back down a bit in-game. Although there is still some noise (which is why I have an X52 for my other stick which works on Hall Effect instead), it is a lot better than it was.

 

 

I can't explain it better than that, but it is, broadly-speaking tolerable until I can work out a decent mechanical solution that will, hopefully, minimise the noise physically.

[FragBum]

Hi

 

 

 

I have converted an X-45 stick into a helicopter flight system and one of the things that I have done is to extend the joystick handle shaft by about 2'. The practical upshot of this is that I am not moving the handle in much smaller circles than would normally be the case and I have had to increase the sensitivity in-game to take this into account.

 

 

 

I would like to alter the stick so that it is more sensitive mechanically / electronically so that I don't have to up the sensitivity in-game. The problem is that using the in-game calibration to increase the sensitivity also amplifies the noise in the pot.

 

 

 

I have been working on using gears to mechanically amplify the movement of the stick but it occurred to me that there might be a better way, swapping out the pots.

 

 

The pot that is in the stick is a B50K-65 and I am assuming, from Googling around, that the 50K is the resistance in the pot. So, the question I have is, could I increase the sensitivity of the stick by putting in a different pot with a different resistance, and would this be a good way of doing things?

 

 

Thanks!

 

 

CptT

 

Well make the extension 4"to 5" ;)

 

It's resolution/fine input you need Put it between your legs and use thumb and one or two fingers for cyclic rest your wrist on your thigh, less input is more control right. :D

[CptTangerine]

Oh, that is exactly what I am doing - especially with the Gazelle. That's pretty sensitive.

[FragBum]

Oh, that is exactly what I am doing - especially with the Gazelle. That's pretty sensitive.

 

Ah the Gazelle sure is but it's more precision you need you should find less input the more control. for all helicopters. :D

 

The dampers mean there is effectively no need for trim especially if the grip is light enough.