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[0.90]NEAR: A Simpler Aerodynamics Model v1.3.1 12/16/14

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There doesn't appear to be any data in there pointing to NEAR. I would advise you to make sure that all your mods are absolutely confirmed fully compatible with 0.24 and remove any that have a hint that they might be incompatible. Then wait for them to update.

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Ok, The download from Kerbal Stuff may still be 1.0.1. The file name says 1.0.2 but the Near.version file contains 1.0.1 as the version number. Is that correct?

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Nope, it's version 1.0.2. I'm bad at getting metadata correct.

Ah ok (me too actually, I do that with my Minecraft plugins all the time). Anyway, It's another plugin, not sure which maybe tweakscale. I dumped down to just NEAR and problem went away. I'll figure it out.

EDIT: After several attempts copying 1 plugin at a time, it turns out it was Action Groups Extended.

Edited by Alshain

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KSP version 0.24.

Parts are shown NOT SHIELDED within KWR fairings with N.E.A.R. and CoL is shown at the very TOP of the rocket. Either it's a bug or N.E.A.R. have rather different means of indication.

Will try again with F.A.R.

Nope... Still "isShielded:False". Something have broken...

Edited by Dr. Jet

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Awesome! I feel that FAR was probably trying to do too much given how limited the part geometry is. This has all the best parts of FAR.

But it breaks ModuleManager configs with :NEEDS[FerramAerospaceResearch], right? I'll probably just rename the folder. Nope, doesn't like to have it's folder renamed, find/replace it is.

Edited by sjjvjixh

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@Dr. Jet: It is an error only in the VAB / SPH. Flight tests indicate that fairings function properly.

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In flight there is no shielding indication at all...

BTW, is there any way to turn off that new aerial disassembly bug feature in FAR? It is ridiculous for rocket to fall in pieces at mere 2G. If it's hardcoded, I'll probably migrate to NEAR.

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In flight there is no shielding indication at all...

BTW, is there any way to turn off that new aerial disassembly bug feature in FAR? It is ridiculous for rocket to fall in pieces at mere 2G. If it's hardcoded, I'll probably migrate to NEAR.

These both involve options that are only available from the Space Center. Click the FAR button, then under Part Right-Click Menu, enable "Display Shielding." In flight, right click the cargo bay or fairing to get a count of shielded parts.

You can also disable aerodynamic failures from the same menu. They're not based on g forces as reported next to the navball, though. They occur because of too much differential air pressure applied across a part connection. You can still have ridiculous TWR if you're willing to go very gentle on the controls.

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@Kingsix: You'll need to post a copy of your output_log.txt from KSP_Data and a full list of reproduction steps. So far, your bug report does not have enough information to determine what, if any, behavior is due to NEAR.

I am going to have to say that this was an act of some greater Kerbal god to keep the Kerbal alive. I cannot reproduce the water event.

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Alright, NEAR v1.0.3 is up, fixing the shielded-in-the-editor issues as well as some more null ref issues.

@Dr. Jet: Well, yes. User feedback for what people wanted that was not FAR not only included removing some complicated aerodynamic features but the attitude that pretty much all the information was unnecessary, confusing, or useless. So it isn't available with NEAR. As for things falling apart with FAR, it's not hard-coded, but it's quite possible for things to come apart at 2g. It's quite possible for wings to come apart at 0.001 g, it's not like the mass of the fuselage reduces the forces on the wing. By that logic a string could hold up an oil tanker so long as the string wasn't accelerating.

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I cannot imagine aerodynamic forces WITHOUT acceleration... Either rotational or translational acceleration, but it always exist if there are any forces applied. Sum of forces (thrust, aerodynamic force and gravity) working against vehicle inertia is treated as G-force. Even in non-moving vehicle acceleration applied to crew is 1G. If wing or rocket cannot withstand 2G maneuver - it's made of paper.

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Fine, here's an easy example of an aerodynamic force without acceleration. F1 car driving on a racetrack; aerodynamic lifting force pushing it down. Movement of the car downwards is blocked by the ground, so there is no acceleration downwards. Still, there is an aerodynamic force there. Surely, you can imagine that force being enough to bend and break those aerodynamic features, right? What about aeroelasticity, where wings break despite relatively low g Forces on the vehicle because they have been twisted and bent by aerodynamic forces?

Acceleration is not the end-all-be-all of things failing. Only stress is.

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Hey I'm a neophyte so I really like this mod (FAR was just too much for me), but I have trouble flying with MJ. When I fly manually I can get a gradual ascent and everything is fine, but when I turn on MJ it starts wobbling A LOT trying to head in the right direction. It got even worse with the RSS mod. Do you know how I can fix that?

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It will handle MJ just as well as FAR will: if you give it the right input parameters it will fly perfectly fine. If you tell it to fly like stock it will not.

Edit: To elaborate, this is a consequence of disconnecting the CoM and CoD. FAR has this "issue," the Stock Drag Fix has this "issue," NEAR has this "issue." The fact is, the only way around instability problems during launches is to simply accept the brokenness of "drag must be proportional to mass at all times, and no dependence on orientation or shape" and argue for no aerodynamic improvements ever.

What this really points to, is not an issue with FAR/NEAR, or MechJeb, but the need for a basic tutorial on using the combination. I wanted to give this some thought and do some research first, however. I've decided not to cover landing guidance, as that's even more tricky than ascent. So here goes the trick to Ascent Guidance with MechJeb/NEAR.

First off. MechJeb uses the stock physics model to do it's calculations and knows NOTHING about what NEAR is doing, so certain features in the ascent guidance module DO NOT FUNCTION with NEAR installed. The important one is "limit to terminal velocity." If you're in the habit of checking this box, uncheck it. Instead, check "Limit acceleration to" and enter the value "23 m/s." This will reduce your acceleration to terminal velocity.

Gravity turn: What MechJeb does ISN'T one, and with NEAR a gravity turn is what you MUST do, or you will tumble out of control. So... We're going to use MechJeb to closely approximate a gravity turn as near as we can.

Take a look at your TWR. If your TWR is 1.2, set your gravity turn to begin at 1.5km. Set your turn percentage to 90%. Set your end of turn to 70km. You will need to play with the end of turn angle to find something which works, but the value will be +- 5 degrees. If your TWR is higher, set your turn lower. For my rocket with a TWR of 1.7, I begin my gravity turn at 700m. The reason for this is that you need to begin your turn at a speed of 100m/s, and the math will tell you at what altitude that is. If your TWR is >2, your turn will begin at ground level. No gravity turn will ever begin higher than 2km. Turn percentage needs to be high, because you are only turning VERY gradually. Turn on the navball guidance and watch as the target point and your velocity vector track together. The better they track, the better your turn. Too far outside this and you will tumble.

This will get you safely into space every time.

Edited by BrianMcNett

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Terminal velocity in NEAR is not terminal velocity in stock. You will not reach terminal velocity in NEAR or FAR without losing control of the rocket long before then, so any terminal-velocity-chasing shenanigans are fruitless.

In fact, terminal velocity in NEAR will be higher than in FAR, since there will be no supersonic drag effects to force terminal V lower. Unless you can manage ~400m/s at the pad and have it increase with decreasing air density, you're not gonna hit terminal velocity and you shouldn't waste time bothering.

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I seem to have come across a bug. When using the MK1 capsule with a part attached to the base of it, the craft will no longer fall in the expected orientation. Instead it seems to fall roughly 90 degrees to the expected direction.

I stripped out all the other mods except NEAR v1.0.3 and can confirm it happens on both the 32 and 64 bit Windows versions. I was able to replicate it using the following vessel:

MK1 Capusule * Stage 1

TR18-A Stack Separator * Stage 2

TR18-A Stack Separator * Stage 3

FL-T100 Fuel Tank

LV-T30 Engine

Launch the craft to a reasonable height and stage the bottom stage (Engine/Tank/Separator) so only the capsule and second separator are left. Turn off SAS and let the craft coast into the air. I would expect the heat shield end of the capsule to face towards the direction of travel, however instead the craft sits sideways - roughly 90 degrees to the direction of travel. If I stage the second separator the craft will then reorientate itself - with heat shield towards the direction of travel.

I have looked at the output logs while this was happening and it was not reporting any errors. If another kerbalnaut could run this test with NEAR that would be great, I have seen it happen with a number of different parts attached below the capsule as well.

Is there any other information I could provide?

@NathanKell The problem still occurs when I have a parachute attached to the top of the capsule so I don't believe it is caused by that. It also makes little sense aerodynamically, although I only have a limited understanding of that.

I have also made a copy of the output log from running the test on the x64 Windows version.

Edited by Kerdan
Updated information

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Not a bug. It's due to how FAR and NEAR handle drag calculation. NEAR detects flat areas by looking for attach nodes that don't have anything attached to them. This is why a nosecone helps: it closes the open node on the top of the rocket. However, the open node on the bottom of the capsule is what stabilizes it. If you close the node by attacing something to it (even an antenna) then NEAR no longer detects it as an open node.

Also, welcome to the forums! As for providing other information, you did provide reproduction steps, which is awesome! However, even though the output log did not report anything that seemed off to you, you should still always post it, in case the modder may notice something you did not.

Edited by NathanKell

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Any chance that we will get a method GetMachNumber(...) like in FAR? Someone asked my to craete a NanoGauge for the current mach number and FF is using this method, too. My personal approximation of mach number is way to... well... approximated. ;)

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Looks like "pre-0.24 craft lag" is not limited to FAR users.

Some crafts that included in FASA (namely Saturn V, Nova, Apollo SA-204, Big G) experience serious lag when NEAR is present. There is NO FAR-related modules in their craft files.

Any help would be appreciated. They're hard to rebuild, and I'd like to use them at least for inaugural flights.

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i have a problem, with this installed all my saved aircrafts has a CoL way too far away from where they were or where they should be. when i start a new craft and build it, i encounter no problems with CoL its only for alrleady saved crafts, this mod is space plane plus and it does have near support cfg file , i dont know what makes this, only allready saved crafts, same problem goes for stock as well

screenshot1.png

screenshot2.png

Edited by TheReaper

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Hi,

I just installed this mod because I find FAR too complicated for me and so far I love it :) But I have encountered one situation and I would like to ask if this is normal behavior of this mod - I build small jet using Spaceplane Plus parts with 2 turbojets and its a bit too fast, right after take off it will reach approx. 780ms on sea level and without any difficulties it can make 75km suborbital hop just with these two turbojets!! It seems to me that spaceplane will be too easy with this behavior. Is it normal?

pSUmHPC.jpg

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I've been slowly approaching the "Realism" mods, as I'm having plenty fun in the stock game. But the relative simplicity of NEAR convinced me to wade in and give it a shot.

On my very first re-entry from the Mun with NEAR, I was coming in highly inclined, and probably going to spash in the water well south and west of KSP. Instead I used my new-found crossrange from body-lift to steer to a landing *on land* just west of KSP. Oh, and this was at about midnight local KSP time, so I did everything with the readouts in KER.

Eventually I'll wade into Deadly Reentry and won't be able to do that with an unshielded lander, but... baby steps. :D

Thanks!

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