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

[sarbian]

If it's stock then post the craft file on pastebin so we can look at it. However I doubt MJ has anything to do with it.

[NotCoach]

Is there a straightforward way to establish a specific phase angle to another orbiting body using MechJeb?

[Galane]

I finally sent something to Duna, a Kethane scanner. Turned out it was a bit under two days to the transfer window. Would be nice if transfer to another planet had an option to just go for it right effing *now* cuz I've loaded up with fuel to burn.

I backed up the quicksave in case things didn't go quite right. Going to start the mission over and change some things. I built the ship to use four boosters docked around the sides but took off with only two. Had plenty of fuel left over even after an ordinary insertion without aerobraking. The re-do mission will include a scanner for Ike, possibly some other stuff too.

[Captain_Party]

@r4m0n This is a huge ask, but is there any chance you could make a version of MJ 2 which weighs stuff in kg?

[Starwaster]

@r4m0n This is a huge ask, but is there any chance you could make a version of MJ 2 which weighs stuff in kg?

'Stuff'? What kind of 'stuff'?

Delta-V window already displays stage mass in kg per stage.... the Vessel window shows the current mass of the entire craft.

If these aren't what you had in mind you should elaborate a bit about what you want exactly.

[Captain_Party]

I meant weight. If theres a way I can do it myself, sure.

[sarbian]

KSP & MJ use the metric system, so Kg are here already.

[Filippe999]

What about a module that creates a node for a "Free-Return" path at n closest approach? just so we can more easily gain science in the new carrer by doing pass missions rather than hohmann transferring and circularization burn, then return from moon burn.

Free-return would accept n, where n means the closest approach you'll have at the target before turning back to the celestial body you were previously orbited, of course this is intended for advanced satelites orbit manuevers.

[Eric S]

I meant weight. If theres a way I can do it myself, sure.

You probably mean mass (mass and weight aren't the same thing), and MJ already outputs in the metric system. The masses are in kg in some places, mg in others, but usually not labeled as such. If you want kg, you either have them, or you have mg (also known as a metric ton, or 1000 kg).

[Starwaster]

KSP & MJ use the metric system, so Kg are here already.

Maybe he's talking about having it report weight by local gravity.

[buckau]

thanks for that info, i have tryed it both way around with one -"-" and the one "+" it gets to 2.9m along side eachother and when bothe are "-" to "-" then it parts alonside eachother facing the wrong way

[softweir]

Did you try "+" to "+"? Both docking ports should have the "hatch" visible on the outside of the component.

[SFJackBauer]

Maybe he's talking about having it report weight by local gravity.

Unrelated, but having the ability to check TWR against other bodies (similar as KER does) in VAB would be handy.

[houlihan]

Unrelated, but having the ability to check TWR against other bodies (similar as KER does) in VAB would be handy.

This would be fantastic.

[Eric S]

This would be fantastic.

I'll third that. I use KER in the VAB and MJ in flight, and that's one of the reasons I use KER in the VAB.

[sojourner]

Unrelated, but having the ability to check TWR against other bodies (similar as KER does) in VAB would be handy.

A drop down box where you could choose the planet added to the existing delta-v window would be the easiest way to do this I would think.

[Virindi]

Ascent guidance seems to have a bug wherein it starts trying to face the rocket retrograde, or at least 90 degrees off from the correct direction. This happens even when there is only one command pod on the ship plus a mechjeb case, and the mechjeb case is facing up. Ascent guidance points in the correct direction for awhile, but at some point after starting the gravity turn it suddenly goes crazy and starts steering the ship wildly in the wrong direction. This only happens on some ships, and only some of the time. Most ships work perfectly. When my large first stage separates, the behavior stops immediately.

SAS or controlling manually easily keeps the rocket on track.

I caught it in action. At the first screenshot, things are going normally. Note the prograde marker is close to the navball guidance marker; everything is pretty much on track. In subsequent screenshots, note the direction MJ is attempting to thrust in: the opposite of what it should.

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Mods: RealSolarSystem, KW, StretchyTanks, Engineer, FAR, etc.

MechJeb 2.1.0 downloaded from this thread.

Edit: I tried without corrective steering and got the same effect.

Edited November 14, 2013 by Virindi

[Roxette]

This may be a known bug or feature, but I've found it an irritating gotcha at times... If an acceleration limit has been set and enabled in the ascent guidance control of MechJeb, then that limit is subsequently applied for that craft until it has been disabled, even though the autopilot is no longer in control.

[UberFuber]

This may be a known bug or feature, but I've found it an irritating gotcha at times... If an acceleration limit has been set and enabled in the ascent guidance control of MechJeb, then that limit is subsequently applied for that craft until it has been disabled, even though the autopilot is no longer in control.

I think that's a feature. If you go to the Utility window, the Acceleration Limit is available there, so it applies to every maneuver the spaceship does.

[Damaske]

Ascent guidance seems to have a bug wherein it starts trying to face the rocket retrograde, or at least 90 degrees off from the correct direction. This happens even when there is only one command pod on the ship plus a mechjeb case, and the mechjeb case is facing up. Ascent guidance points in the correct direction for awhile, but at some point after starting the gravity turn it suddenly goes crazy and starts steering the ship wildly in the wrong direction. This only happens on some ships, and only some of the time. Most ships work perfectly. When my large first stage separates, the behavior stops immediately.

SAS or controlling manually easily keeps the rocket on track.

I caught it in action. At the first screenshot, things are going normally. Note the prograde marker is close to the navball guidance marker; everything is pretty much on track. In subsequent screenshots, note the direction MJ is attempting to thrust in: the opposite of what it should.

Mods: RealSolarSystem, KW, StretchyTanks, Engineer, FAR, etc.

MechJeb 2.1.0 downloaded from this thread.

Edit: I tried without corrective steering and got the same effect.

I have experienced the ascent assistance bug the you spoke of but just thought it was my rocket being all screwed up. glad to hear it was not just me and i have a good craft. I've also found that When using a spaceplane trying to use the ascent assistance it will start to flip, roll and spin out of control. as with the space plane NEVER point toward the center of the guidance point its always too high but within the circle.

The one thing that really gets me is how the autoland for the spaceplane guidance is screwed up, since i have yet to learn to land proper all my SSTO trips have ended in crashes and the time i spent in the mission is wasted as i am forced to revert to hanger because the kerbals i DID NOT want on the craft ARE INDEED inside it despite my changing crew in the spaceplane hanger. I could put chutes on them and drop to the ground with them BUT then its not a true resuable as i have no way to repack the chutes on the fly.

This may be a known bug or feature, but I've found it an irritating gotcha at times... If an acceleration limit has been set and enabled in the ascent guidance control of MechJeb, then that limit is subsequently applied for that craft until it has been disabled, even though the autopilot is no longer in control.

I kinda like that the Acceleration limit if set being applied even outside of autopilot and find that it is very useful for later stage of flight for my larger multi-engine craft.

[Roxette]

I think that's a feature. If you go to the Utility window, the Acceleration Limit is available there, so it applies to every maneuver the spaceship does.

Fair enough, although perhaps there should be some visual indicator that this has been selected, so it can be noticed and disabled before it interferes with an otherwise carefully planned manoeuvre?

[Roxette]

On further thought about this, perhaps if the tab of the mechjeb interface was changed to a highlight colour when any of its control systems were in operation, such that if there was a system active but no windows were open it would still be easily noticable ?

[Starwaster]

This may be a known bug or feature, but I've found it an irritating gotcha at times... If an acceleration limit has been set and enabled in the ascent guidance control of MechJeb, then that limit is subsequently applied for that craft until it has been disabled, even though the autopilot is no longer in control.

Throttle limits are independent of autopilot control. They are supposed to apply regardless of whether or not autolpilot is engaged. Turn them off if you don't want them applied.

[buckau]

Sounds like you have one or both of the ports on backwards. I've docked those ports using MJ before with no trouble. There's nothing unusual about them that would prevent MJ from docking them.

thanks for the info i think i have found the problem. is it possiblew to edit the ship/craft file after it is in space? and if so how. (it looks like i put the port on backwards and would like to fix it with out having to redo the take off again.

[sojourner]

Possible? yes. Easy to do? No. You'd spend less time just relaunching.