Board index FlightGear Development Aircraft Autopilot and route manager

B1900D AP

Designing a stable autopilot is one of the hardest things. Need help?

B1900D AP

Postby jaxsin » Mon Jan 25, 2016 7:01 pm

I been rather curious after flying around in the B1900D about how the AP actually works. What I found is that it needs some fine tuning and a few features introduced. I've read the 'how-to' article on AP and I understand how it works. But I was curious on a few things before I set off to see if I can improve on the AP of this aircraft or not.

The one thing that I looked at first was the 'ALT' mode of the FCP-65, it works in that it will grab the current altitude and stable the airplane in on that alt. The problem arises when AP kicks in, it jerks the plane causing it to become unstable before it settles. This is also noticeable I think when you go from one local airport to another when flying, if the baro. changes the AP will see this and immediately jerk down or up to adjust the altitude causing it to become unstable and start the process of settling again.

I am not sure if the initial KP needs to be changed or if this is one of those situations that dictates a <filter> element to slow down the immediate changes in elevator and make it more natural? I'm all in for updating this model

Also, if I can fix the altitude hold, then I believe I can easily finish creating the altset, climb, dsc features that are currently missing. I also think the AP can be tweaked a little but with such limited knowledge of flying in general, all i can offer up is my efforts fixing and tweaking code if I have ideas on how to do it.
jaxsin
 
Posts: 396
Joined: Mon Dec 28, 2015 3:54 pm

Re: B1900D AP

Postby jaxsin » Tue Jan 26, 2016 12:22 am

So here is one of those questions I have because I am not really a pilot. I seen from some pictures on google that the FCP-65 has a 'altset' row 2 column 2

Where exactly is this altitude number supposed to come from in RL? where is the input to set the required altitude? Where would be the appropriate place to take that info from the internal properties of FG during a flight?
jaxsin
 
Posts: 396
Joined: Mon Dec 28, 2015 3:54 pm


Return to Autopilot and route manager

Who is online

Users browsing this forum: No registered users and 1 guest