[PART, 1.0.2] Anatid Robotics / MuMech - MechJeb - Autopilot - Historical thread

[Shadriss]

See... the odd thing about MJ not properly taking the craft to orbit is this: So you place it in autopilot, and the throttles are left untouched. Turn it OFF afterwards, and it zeros the throttle, so there is still some connection there that is working. While en-route to orbit, if you manually take care of the throttles, it will still change the craft's course as normal, so that works. The messages at the bottom of the Ascent box still update and swap according to the proper events, IE, once I have the apoapsis where I want it, it updates from 'Gravity Turn' to 'Coasting to Edge of Atmosphere'. So again, that portion is seemingly still working. All other aspects I've tested of MJ still function as I expect, though I've not had reason to do rendezvous or docking evolutions yet.

I'm no coder, but to me, it would seem that something was either accidentally edited in the throttle control area, or the full version of Kerbal changed something somewhere so that the previous code is no longer reliable. It's still a great mod, and I can still use it for a great many things, but at least on my end, there's something definitely hinky.

[Radam]

Im not sure if anyone asked this already, but Im using MJ to see how much drag the vehicle has. Thing is, it only works outside VAB or SPH.

Is there a way to calculate this in VAB/SPH at perfect prograde orientation?

[ss8913]

Im not sure if anyone asked this already, but Im using MJ to see how much drag the vehicle has. Thing is, it only works outside VAB or SPH.

Is there a way to calculate this in VAB/SPH at perfect prograde orientation?

Install the new version of FAR. It will show you all the aero calculations inside the SPH/VAB.

- - - Updated - - -

See... the odd thing about MJ not properly taking the craft to orbit is this: So you place it in autopilot, and the throttles are left untouched. Turn it OFF afterwards, and it zeros the throttle, so there is still some connection there that is working. While en-route to orbit, if you manually take care of the throttles, it will still change the craft's course as normal, so that works. The messages at the bottom of the Ascent box still update and swap according to the proper events, IE, once I have the apoapsis where I want it, it updates from 'Gravity Turn' to 'Coasting to Edge of Atmosphere'. So again, that portion is seemingly still working. All other aspects I've tested of MJ still function as I expect, though I've not had reason to do rendezvous or docking evolutions yet.

I'm no coder, but to me, it would seem that something was either accidentally edited in the throttle control area, or the full version of Kerbal changed something somewhere so that the previous code is no longer reliable. It's still a great mod, and I can still use it for a great many things, but at least on my end, there's something definitely hinky.

The current MJ2 dev build seems to work for me for all functions except for landing accurately on atmospheric bodies, which the Landing Guidance box clearly says is known to not work 100% in the current build. It gets a little ticked off if you try to dock with something that's *rotating*, I found out, but you can't really blame it for that. It integrates at least as well with the new FAR as it did with the old one - in some ways, better - landing autopilot left to its own devices gets me within 10km of my intended target on Kerbin (from a 100km circular orbit) - in 0.90 with that version of FAR it was almost 60km, sometimes more, depending on a few other variables.

Current dev build also solves the FAR incompatibility with "Show landing predictions" that was killing framerates... so it seems pretty solid all around, at least for me, using FAR, in 1.0.2.

[Shadriss]

The current MJ2 dev build seems to work for me for all functions except for landing accurately on atmospheric bodies, which the Landing Guidance box clearly says is known to not work 100% in the current build. It gets a little ticked off if you try to dock with something that's *rotating*, I found out, but you can't really blame it for that. It integrates at least as well with the new FAR as it did with the old one - in some ways, better - landing autopilot left to its own devices gets me within 10km of my intended target on Kerbin (from a 100km circular orbit) - in 0.90 with that version of FAR it was almost 60km, sometimes more, depending on a few other variables.

Current dev build also solves the FAR incompatibility with "Show landing predictions" that was killing framerates... so it seems pretty solid all around, at least for me, using FAR, in 1.0.2.

Happy to hear that it's apparently just a few isolated cases - however in both Moo's case and my own we are not running with FAR. This makes me now wonder if, perhaps, MJ has come to rely on FAR somehow (inadvertently, I'm sure) such that it working with the Stock aero system somehow throws a wrench in the works. Whatever the case, I'm sure Sarbian is working on it. Hopefully, the next dev build will fix this. Or the one after. Or the one after. As long as it takes. If my only problem is the ascent guidance AP, then it still takes care of far more piloting for me than I would have to otherwise do.

[futrtrubl]

Happy to hear that it's apparently just a few isolated cases - however in both Moo's case and my own we are not running with FAR. This makes me now wonder if, perhaps, MJ has come to rely on FAR somehow (inadvertently, I'm sure) such that it working with the Stock aero system somehow throws a wrench in the works. Whatever the case, I'm sure Sarbian is working on it. Hopefully, the next dev build will fix this. Or the one after. Or the one after. As long as it takes. If my only problem is the ascent guidance AP, then it still takes care of far more piloting for me than I would have to otherwise do.

It is actually far easier to work with FAR (hohoho) than with stock aero for predictions. FAR's code is known at worst and at best it will tell you what you want to know if asked nicely. Stock.... isn't and doesn't.

[ivanwong1989]

Hi All, Newbie question. KSP 1.0.2. I had FAR installed. and Mechjeb dev version.

Using the stock Kerbal-X rocket, i used mechjeb for ascent guidance. Autipilot, default settings didn' touch anything..

Apparently when it reaches circularization phase, mechjeb starts to engage engines(Poodle engine)... and that causes the final stage of the rocket to spin out of control. wildly. Hence circularization failed.... may I ask why??? Problem with the stock craft? or mechjeb?

[ivanwong1989]

Hi All, KSP Newbie here,

Mods installed are FAR. KSP version 1.0.2

I am using Mechjeb dev version.

Using the stock Kerbal-X, mechjeb Ascent guidance can't get it to orbit automatically. The problem happens when Mechjeb tries to burn for circularization at Apoasis after gravity turn and coasting. Whenever Mechjeb tries to engage the engines to circularize..... it cause the rocket to spin wildly out of control. Any idea why?? Mechjeb or Kerbal-X Rocket's problem?

[Toyotawolf]

Yes, my build server post each dev release on CKAN.

and this is why sarbian rocks

[Radam]

Install the new version of FAR. It will show you all the aero calculations inside the SPH/VAB.

Lets say I also want the 1.02 atmosphere?

[acerola]

Hi All, KSP Newbie here,

Mods installed are FAR. KSP version 1.0.2

I am using Mechjeb dev version.

Using the stock Kerbal-X, mechjeb Ascent guidance can't get it to orbit automatically. The problem happens when Mechjeb tries to burn for circularization at Apoasis after gravity turn and coasting. Whenever Mechjeb tries to engage the engines to circularize..... it cause the rocket to spin wildly out of control. Any idea why?? Mechjeb or Kerbal-X Rocket's problem?

I don't have FAR installed. I just tried Kerbal-X and MechJeb 449 managed to put it in orbit at 75km with 500 dv still left in the mainsail stage.

[ivanwong1989]

Hmm..

When I was at mainsail stage, coasting to apoasis, then when it's time for the circularization burn, mechjeb put's full throttle, and the rocket flings wildly missing it's intended plan.

Hmm..... but it's already so high up, shouldn't be FAR's effect right?hmm.... Or maybe I am just too noob. =P

[sarbian]

Lets say I also want the 1.02 atmosphere?

You wait for me to add the required code (I had to remove the old code for the editor for 1.0)

[acerola]

Hmm..

When I was at mainsail stage, coasting to apoasis, then when it's time for the circularization burn, mechjeb put's full throttle, and the rocket flings wildly missing it's intended plan.

Hmm..... but it's already so high up, shouldn't be FAR's effect right?hmm.... Or maybe I am just too noob. =P

The KerbalX does not have reaction wheels. So it relies on the engine to turn around.

If you exit the atmosphere not aligned with the maneuver node, MechJeb might try to turn too hard, making the rocket spin when the engines kick in.

[ivanwong1989]

The KerbalX does not have reaction wheels. So it relies on the engine to turn around.

If you exit the atmosphere not aligned with the maneuver node, MechJeb might try to turn too hard, making the rocket spin when the engines kick in.

I tried putting on reaction wheels. Thank you very much!. Now I know why. No problem now. Having fun

[sarbian]

Nope, the pod has a reaction wheel.

I won't help with such problem without a log. It works fine here (and putting a kerbalX on orbit is my standard test) so the problem is most likely not obvious.

[smjjames]

Sarbian, is the 'threw exception in drive' thing that I mentioned back here: http://forum.kerbalspaceprogram.com/threads/12384-PART-1-0-Anatid-Robotics-MuMech-MechJeb-Autopilot-v2-5?p=1932673&viewfull=1#post1932673 something that can just be ignored?

[curiousepic]

Is info on rate of rotation in each axis hidden away in MJ's options anywhere I haven't been able to find?

[Aldmehr]

Is there a way to disable/blacklist the "Online Manual" button?

[Oron]

Ignore please!

Edited May 14, 2015 by Oron

[nobodyhasthis]

I have noticed there seems to no way to change argument of periapsis using mechjeb build 445. I am pretty sure it was possible to do this before. Any ideas please?

Is it still locked in my tech tree?

Removed from mechjeb?

Still in Mechjeb but and there is a bug on my save game?

Any ideas welcome. Thanks ;-)

[smjjames]

I have noticed there seems to no way to change argument of periapsis using mechjeb build 445. I am pretty sure it was possible to do this before. Any ideas please?

Is it still locked in my tech tree?

Removed from mechjeb?

Still in Mechjeb but and there is a bug on my save game?

Any ideas welcome. Thanks ;-)

Not sure if I remember if there was an option for that, don't think there was. If it was removed, I have no knowledge about it.

In any case, not in my game either, using dev build 455 with everything unlocked.

[nobodyhasthis]

Not sure if I remember if there was an option for that, don't think there was. If it was removed, I have no knowledge about it. In any case, not in my game either, using dev build 455 with everything unlocked.

Ok thanks, I must sleep. Think I am having confusion with a change in longitude of ascending node

[Gunso]

hi, just want to ask. I'm using the current dev version. Does the ascent path editor still work or the new ksp broke it? I've been wondering because i noticed the gravity turns starts at the same height no matter what value i set in the editor.

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Everything else seems fine to me (only used it up to minmus on career mode tho). At 1st I'm kinda puzzled with the rocket spinning at mid air the 1st few times but manage to fix it by reducing the % thingy on the ascent guidance(also saw in forum about top heavy rocket). Last night tried the auto landing on kerbin, 1-2km diff from the hq is really quite nice i would say.

This new issues with the new atmosphere kinda gave me an idea for career mode. Imagine if u need to do contract missions of collecting data for the atmosphere 1st at multiple level and area and only after doing that mechjeb will be able to be used properly in that planet atmosphere. So if u go to a new planet, u need to drop a few probes before mechjeb can do proper calculation for the landing. If not the landing will be like when ksp broke mechjeb with the new atmosphere update XD

that gonna be fun

[futrtrubl]

hi, just want to ask. I'm using the current dev version. Does the ascent path editor still work or the new ksp broke it? I've been wondering because i noticed the gravity turns starts at the same height no matter what value i set in the editor.

There are now two turn start parameters, altitude and speed. It turns once either of them is met. So if you are hitting the speed well before the altitude then changing the altitude won't have an effect unless you change it enough to occur before you reach the speed.

[Gunso]

There are now two turn start parameters, altitude and speed. It turns once either of them is met. So if you are hitting the speed well before the altitude then changing the altitude won't have an effect unless you change it enough to occur before you reach the speed.

ahhh now i get it, thanks. So if i want to turn at higher alt, i'll need to manage my speed accordingly. Now i know what to tweak on my rocket design.