Problem Universal Auto Pilot (UAP) MFD and rendez vous (sync) problem

[Constellation-75]

Hi folks

I got a very annoying problem with UAP...

When i cant to sync orbit (shuttle to ISS), it alsays says that it can't find any sync solution

I tried everything :

Long before the sync window, believing I just had to wait until the sync burn (like in IMDF or any other AP I know). Didn't worked.

When the shuttle was close to the ISS. Same thing

With a target distance of 5000 (default) it doesn't work
With the target distance I cant (200) Same thing.

My orbit is 80 to 90 km lower than the ISS if that helps... (255 km ALt)

I hope that someone can help me on this one 'cause It drives me crazy now....

 

[Spacethingy]

Might've been best to ask this on the addon's thread...

What time acceleration were you using? Artlav said it does sort of protect against using high accel.s, but sometimes not...

 

[Constellation-75]

Well I use X10 and X100. ans sometimes X1000 when the wait is very very super long.

But it has nothing to see with Time accel, because, when I press "GO" it sans "thinking" then "unable to find a solution" (or something like this I don't remember exactly) before returning to the setup menu.

And I NEVER use the time warp when I set up my MFD's...

 

[Artlav]

Are you using some kind of Shuttle add-on (SSU, Shuttle fleet)?
Try replacing it in a scenario with default Atlantis and try again.

If that does work, then it's likely a problem with SSU/SF defining engines in non-default way, not something i can fix in a blink.
If that doesn't work, then i can't think of a reason, and i won't be near an Orbiter-capable computer until august.

 

[Constellation-75]

Thanks

Yep it's Shuttle fleet and the ISS by thorton. The strange thing is that it does everything except this.
Align Plane works just fine and docking too. But I'll try with the XR2 (worked in the past) and with the DG II.

The thing is that I totally rely on an autopilot for Orbital RDV. So If UAP doesn't work with one ship, then this ship is back to the hangar...

 

[IronRain]

I had this too some time ago (with an other add-on though). Changing (read increasing) the delta-v did the trick for me.

 

[Constellation-75]

I'll try then. But when can we actually luanch the autopilot ?
When we want ? (and we wait until the burn, like in IMFD)
Or, when the burn gotta start (so it will start the burn exactly when you press go, whatever the distance between you and the target)

 

[Slaintemaith]

It says on Orbit Hangar:

Known issues:
-It appears that Shuttle Fleet uses something like engine gimballing for pitch control instead of RCS, making it uncontrollable for the UAP. Won't be easy to fix.

...unless it's been fixed and I'm just not aware of it.

 

[Constellation-75]

tested with the XR2. It starts when I set the distance to 5000 default distace, witch is WAY TOO FAR.
And it doesn't work at all. It miss miserably the ISS.

Either I'm too dumb to know how to use this thing (the manual doesn't really helps as it only says what does what, but no how to do); Either My chitty computer had decided to piss me off one more time. After the USB bugs, the CD bugs, the FS9 problems, the "I go on the internet when I want" bug. it's the "You play Orbiter when I want to" bug.

I can't wait to buy a new one...

Can comeone make me a little tutorial about space RDV with this autopilot please ???

EDIT : It "Worked". at a distance of 5000, so completely useless, I came close enough to the ISS to actually see it. BUT, no other burn to "stop" the XR2. I just missed it !!! And the RDV procedure was soo strange : instead of waiting for a burn, and then go directly to the ISS, a small burn, then 6 orbits before "reaching" the ISS...

OMG. WHY NOTHINGS WORKS WITH ME !!!

 

[Cras]

I have been able to have the UAP automatically launch and dock with the ISS the DG-IV several times. All I had to do was press the go button, activate the turbo pump, and open the nose cone.

First, I think the eccentricity of the ISS's orbit need to be very small. The more circular the better, so before I launch, I correct the ISS's orbit if it some how got messed up a mission earlier.

Then have a list of commands,
runway off to 1KM altitude,
lift off for 200 or so seconds at 60 degrees pitch
trans orbit to something like 280 KM Apogee and 250KM perigee,
align the orbit with the ISS
sync with the ISS using minimum delta-v
rendezvous to 5000 at 50 m/s velocity
then docking auto pilot.

If the Sync fails, and there are times when it does, fire up Rendezvous MFD and wait until I catch up to the ISS, which I certainly will since I am at a lower orbit. When I am close enough for Rendezvous MFD to come alive, set the time to 2400, then slowly adjust until it displays an arrival speed that I can manage to control. Burn on the burn vector and watch as I slowly approach on the R-bar of the ISS, then can either use the DG-IV autopilot to dock, or open UAP again and fire up the Docking autopilot (which likes to approach at much higher speeds than I would ever attempt to do if docking manually!)

 

[Constellation-75]

hi. Well it's with a little shame that I discovered what's wrong with UAP.

It was all my fault : the RDV procedures requires 2 steps. The sync, and the approach. One can't work without the other... And I forgoted the "approach" step... Now It worked perfectly, with Shuttle Fleet and the XR2, even on the moon. I also made my first moon landing ever with the XR2.

Now back to the only part that doesn't have any AP to do it : the reentry. The XR2 features an attitude autopilot that really really helps, but there's no reentry burn auropilot. Cross my fingers and hope I'll land at the KSC...

 

[PhantomCruiser]

BasesyncMFD and AerobrakeMFD should be two of your best friends for a good landing/recovery at the airstrip of your choice.
http://orbiter-forum.com/showthread.php?t=8425 Oceanic's awesome tutorial here allowed me to put a DGIV or an XR-(series) on a dime.

 

[Constellation-75]

Thanks. I already had these two, but didn't know how to use it; Only one out of ten reentries was a success; For aerobrake, I never understood it. But I was always been able to find the good reentry angle by modifing the pitch angle and using the map mfd...

I'll read the tutorial and try it immediatly. Now I gotta find a solution for shuttle fleet. 'Cause it's soo hard to keep the attitude during the reentry (harder than ever with the numbad !!!)

 

[Artlav]

Hm, i thought it was clear...

Sync orbits is a quite rough minimisation algorithm - if you set final distance to something small, it will get lost in uncertainty and almost never work - the larger the distance, the better the chances.
I kind of missed you mentioning it and assumed you meant approach one, sorry.

After sync gets you within 50-100 km of the target, approach program is supposed to take care of the rest.

After approach getting you within 50-100 meters from target, docking program can get you to the port.

About reentry - it's a much less generic task that all others, so i wasn't able to make a good one yet.

After all, UAP was designed as a framework for writing autopilots in, writing ALL autopilots from scratch was never my intention, but nobody ever as much as expressed interest in making one for it.

 

[Wishbone]

We are way too modest... :lol: Where's the API, one wonders, cause there are a few ideas on attitude control.

 

[Slaintemaith]

The 'easiest' solution for the Shuttle Fleet lies with using Orbiter 2006 and all the Shuttle Goodies associated with it. Then AutoFCS works--which will reenter and land you. And STS Guidance MFD works which will plop you into whatever orbit you like, and rendezvous you with one click of a button (and a lot of waiting).

 

[Constellation-75]

Yep, but I can't go back on 2006 when I see all the enhancements of the 2010 version. Too bad for auto FCS. The attitude thing is THE problem. We can't keep the shuttle at 40° picth all that time. You got to be a god-like pilot to do this...

 

[Interceptor]

They are working on a new AUTOFCS,that will work in orbiter2010P1,we just have to be patient.

 

[Cras]

Thanks. I already had these two, but didn't know how to use it; Only one out of ten reentries was a success; For aerobrake, I never understood it. But I was always been able to find the good reentry angle by modifing the pitch angle and using the map mfd...

I'll read the tutorial and try it immediatly. Now I gotta find a solution for shuttle fleet. 'Cause it's soo hard to keep the attitude during the reentry (harder than ever with the numbad !!!)

For Shuttle Fleet, Glideslope MFD is a MUST. If you are using a version that is without AutoFCS, you need Glideslope MFD. It has what it calls "automatic steering", it will hold the 40 degree AoA, and dampens the roll when performing a roll reversal, so when you let go of the stick (or the numpad), it will hold the Shuttle at that bank. It also has a few displays that makes it very easy to manage the engery of the shuttle and the approach azimuth so you can use the roll reversals to get you lined up perfectly with KSC, or which ever runway you are aiming for.

 

[Constellation-75]

Hi, to Artlav , I didn't mentionned the CTD problems (Cf Orbiter Dan Steph forums) because they have nothing to do with UAP.

The problem is aboit either orbiter it self, either about my computer. It seems that my orbiter can't load more than one scenario. Once I close the simulation session, it can't reload a scenario whatever the spacecraft is.
But, again, this has nothing to do with UAP. That's why I didn't mentionned it...

Thanks Cras for the info. I'll search Orbit hangar pretty soon and test it. If the shuttle can pass the reentry with sucess, then I just got to learn how to use base sync and il will be allright....