[1.12.x] Transfer Window Planner v1.8.0.0 (April 11)

[Sigma88]

I really love this mod, lately I have been thinking of using it to do some gravity assist and even if it's actually doable it's not that easy.

Would it be difficult to add some kind of search mode in which you could add some parameters like max time, max dV, desired departure/arrival (roughly) and then get some comparison between going straight for the target or doing an assist around another planet?

For example, let's say I am currently at year 1 day 250. and want to get a probe to jool before year 1 day 550 with a maximum dV pool of 7k

this tool already tells me that I can do it with 5581 dV leaving day 250 going straight from kerbin to jool arriving there in 300 days

is there a way to find out if a gravity assist could save me time and or dV?

[Alshain]

What I do with the numbers I get? I cannot find info anywhere

Download precise node. Create a maneuver node. The PN window will pop up.

From there you can Type the UT exactly as shown in TWP (or KAC if you saved it as an alarm). Type the Prograde dV and Normal dV as shown as well.

From there, adjust your maneuver node in your orbit so the Ejection Angle shows as close to the TWP report as you can, this will of course change the UT you typed but that is ok.

Now Adjust the Ejection Inclination until it matches as well.

This will get you real close but you may still have to make minor adjustments to find the encounter, it's not perfect, but it gets you in the ballpark.

Be warned that there is a number display format difference. TWP uses positive and negative, while PreciseNode uses north and south for inclinations. (north is positive, south is negative)

Likewise TWP uses a 360 degree angle from Apoapsis while PreciseNode use 180 degrees from Ap or Pe. If you see an ejection angle in TWP greater than 180, subtract 180 and that will be angle from Pe.

EDIT: I may have those backward, I'm writing this from memory. I can't remember which one uses which format but if it's backward, you still have the explanation you need to make it work.

Edited February 4, 2015 by Alshain

[MoridinUK]

Download precise node. Create a maneuver node. The PN window will pop up.

From there you can Type the UT exactly as shown in TWP (or KAC if you saved it as an alarm). Type the Prograde dV and Normal dV as shown as well.

From there, adjust your maneuver node in your orbit so the Ejection Angle shows as close to the TWP report as you can, this will of course change the UT you typed but that is ok.

Now Adjust the Ejection Inclination until it matches as well.

This will get you real close but you may still have to make minor adjustments to find the encounter, it's not perfect, but it gets you in the ballpark.

Be warned that there is a number display format difference. TWP uses positive and negative, while PreciseNode uses north and south for inclinations. (north is positive, south is negative)

Likewise TWP uses a 360 degree angle from Apoapsis while PreciseNode use 180 degrees from Ap or Pe. If you see an ejection angle in TWP greater than 180, subtract 180 and that will be angle from Pe.

EDIT: I may have those backward, I'm writing this from memory. I can't remember which one uses which format but if it's backward, you still have the explanation you need to make it work.

Ok dumb question one, by "Adjust your maneuver node in your orbit so the Ejection Angle shows as close" do you mean to move the node along the orbit/time or adjust the Dvs to get the right ejection angle at the right time?

dumb question two, "Now Adjust the Ejection Inclination until it matches as well" How does one do this? with the Normal/AntiNormal Dv box or by some other means? Wont burning to change inc, cause you ejection angle to change?

I'm sorry I'm just really confused...

[Shurikeeen]

Download precise node. Create a maneuver node. The PN window will pop up.

From there you can Type the UT exactly as shown in TWP (or KAC if you saved it as an alarm). Type the Prograde dV and Normal dV as shown as well.

From there, adjust your maneuver node in your orbit so the Ejection Angle shows as close to the TWP report as you can, this will of course change the UT you typed but that is ok.

Now Adjust the Ejection Inclination until it matches as well.

This will get you real close but you may still have to make minor adjustments to find the encounter, it's not perfect, but it gets you in the ballpark.

Be warned that there is a number display format difference. TWP uses positive and negative, while PreciseNode uses north and south for inclinations. (north is positive, south is negative)

Likewise TWP uses a 360 degree angle from Apoapsis while PreciseNode use 180 degrees from Ap or Pe. If you see an ejection angle in TWP greater than 180, subtract 180 and that will be angle from Pe.

EDIT: I may have those backward, I'm writing this from memory. I can't remember which one uses which format but if it's backward, you still have the explanation you need to make it work.

When I try to move the node after inserting the UT, time for the node resets from 30 days to 5 minutes.

[Eleven]

So I replaced the 'copy to clipboard' button code with this:

var transfer = mbTWP.windowMain.TransferSelected;
var node = FlightGlobals.ActiveVessel.patchedConicSolver.AddManeuverNode(transfer.DepartureTime);
node.OnGizmoUpdated(new Vector3d(0, transfer.EjectionDVNormal, transfer.EjectionDVPrograde), transfer.DepartureTime);

And now I have one-click node creation that just requires some simple UT +/- adjustment via precisenode. It would be nice if you could add this to the mod officially, it simplifies the entire process greatly.

This is the number one thing I would wish for in the mod. Is there a way for noobs to incorporate this fix until TriggerAu does something like this in an official release?

[Telanor]

Is that with a circular equatorial orbit for the active vessel?

Yes, and it will probably require more UT adjustment the more eccentric your orbit, but it still saves a lot of time.

This is the number one thing I would wish for in the mod. Is there a way for noobs to incorporate this fix until TriggerAu does something like this in an official release?

Visual studio is free, you can install it and compile the mod yourself. The KSP wiki has a guide on compiling mods. Step 6 is the important one. In the code, you only need to change TWPWindow.cs:

if (GUI.Button(new Rect(132 + 15, WindowRect.height - 30, 120, 20), new GUIContent("  Copy Details", Resources.btnCopy)))
{
	CopyAllDetailsToClipboard();
}

to

if(GUI.Button(new Rect(132 + 15, WindowRect.height - 30, 120, 20), new GUIContent("  Create Node", Resources.btnCopy)))
{
	var transfer = mbTWP.windowMain.TransferSelected;
	var node = FlightGlobals.ActiveVessel.patchedConicSolver.AddManeuverNode(transfer.DepartureTime);
	node.OnGizmoUpdated(new Vector3d(0, transfer.EjectionDVNormal, transfer.EjectionDVPrograde), transfer.DepartureTime);
}

[Eleven]

Visual studio is free, you can install it and compile the mod yourself. The KSP wiki has a guide on compiling mods. Step 6 is the important one. In the code, you only need to change TWPWindow.cs:

What about linux? I don't use windows at all

[Telanor]

What about linux? I don't use windows at all

http://wiki.kerbalspaceprogram.com/wiki/Setting_up_MonoDevelop. Looks like step 3 is the one to pay attention to there

[Luten]

I wanted to report it as Transfer Windows Planner bug but I read there is year display limit for KSP.

"68 year limit"

Before (max year 68 ; day 359)

After set year 69

And in space taracking

So is there any way to fix it? Because above year 69, Transfer Windows Planner is useless. I know (as I said) it's a game problem but maybe someone have solution. I really would like to use Transfer Windows Planner It's very helpful mod.

Edit:

I had to change UT value in save game file and set it to a lower value.

Edited March 22, 2015 by Luten

[TriggerAu]

I wanted to report it as Transfer Windows Planner bug but I read there is year display limit for KSP.

....

I think this one should be fixed by a change I had to make to the Date Library for large numbers. Let me know if its not

v1.3.0.0 Now Available - Download from GitHub or Download from Curse* or Download from Kerbal Stuff * Once it's approved

• Recompiled for 1.0
  
• Code changes for launcher
  
• Updated KAC Wrapper
  
• Adjusted Editor Lock type
  

[Guest]

v1.3.0.0 reports in avc checker as 1,0,2 incompatible, but works fine. Seems to need small update to report 1.0.2 ok in avc

[TriggerAu]

v1.3.0.0 reports in avc checker as 1,0,2 incompatible, but works fine. Seems to need small update to report 1.0.2 ok in avc

Thanks Aazard, I fixed KAC and ARP last night and have had confirmation that my new version thing is right - will fix this one tonight

[TriggerAu]

And fixed for CKAN/AVC

v1.3.0.1 Now Available - Download from GitHub or Download from Curse* or Download from Kerbal Stuff * Once it's approved

• changed version file to handle patches for CKAN
  

[funkcanna]

Hey, just wondering why Transfer Window Planner and KAC give different windows for transfer?

[undercoveryankee]

Hey, just wondering why Transfer Window Planner and KAC give different windows for transfer?

Transfer Window Planner takes into account the eccentricity and inclination of the orbits. The functionality in KAC is based on an older calculator that used approximations that are exact only for coplanar circular orbits. The KAC dates will put you in the window for a feasible Hohmann transfer, but with no guarantees about the plane change that might come with it. Windows found by Transfer Window Planner may choose an off-Hohmann transfer to depart or arrive on an ascending or descending node if the reduced plane change cost gives a more efficient overall trajectory.

[funkcanna]

Transfer Window Planner takes into account the eccentricity and inclination of the orbits. The functionality in KAC is based on an older calculator that used approximations that are exact only for coplanar circular orbits. The KAC dates will put you in the window for a feasible Hohmann transfer, but with no guarantees about the plane change that might come with it. Windows found by Transfer Window Planner may choose an off-Hohmann transfer to depart or arrive on an ascending or descending node if the reduced plane change cost gives a more efficient overall trajectory.

Awesome, thank you!

[Windspren]

Does this make a manuver node for you?

[Eleven]

Not sure if I'm doing something wrong, I have OPM installed and I can't get TWP to calculate a transfer from any of the moons of Sarnus back to Kerbin.

[dom700]

You can only have it calculate a transfer window from planet to planet, here: From Sarnus to Kerbin

[Eleven]

You can only have it calculate a transfer window from planet to planet, here: From Sarnus to Kerbin

Yea I realized after I wrote that, I misspoke. I cannot even choose Sarnus as the origin. It defaults to one of the moons and I can only choose another moon as a destination.

[TriggerAu]

Does this make a manuver node for you?

Sorry not yet, I cant get the maths to work, but will try again soon - this will be my 4th go at it

Yea I realized after I wrote that, I misspoke. I cannot even choose Sarnus as the origin. It defaults to one of the moons and I can only choose another moon as a destination.

Have never tried Outer Planets myself, but it should list all the planets that are children of another body as the source, and then choose another body that is orbiting the same parent as the origin for the target list. I'll install OPM and have a look soonish

[Eleven]

Have never tried Outer Planets myself, but it should list all the planets that are children of another body as the source, and then choose another body that is orbiting the same parent as the origin for the target list. I'll install OPM and have a look soonish

Seems like half the time when I tried to choose Sarnus it would just choose Pol by itself, sometimes it would go to one of Sarnus' moons, but then I could only choose another moon for the destination. I did end up getting it to set Sarnus as the origin one time, so that was a win! Seems like it has a mind of it's own concerning that Mod

[TriggerAu]

Seems like half the time when I tried to choose Sarnus it would just choose Pol by itself, sometimes it would go to one of Sarnus' moons, but then I could only choose another moon for the destination. I did end up getting it to set Sarnus as the origin one time, so that was a win! Seems like it has a mind of it's own concerning that Mod

Definitely somethin weird going on there, I have an inklin its to do with how many bodies there are in the list, once you go past Jool you start to get weirdness. Will add an issue to the bugtracker and work on it when I have a bit (https://github.com/TriggerAu/TransferWindowPlanner/issues/33)

[dom700]

I am having a similiar issue with New Horizon, clicking on the lower half of the "Kerbin" box, selects "Mun" instead, no idea why

[TriggerAu]

I am having a similiar issue with New Horizon, clicking on the lower half of the "Kerbin" box, selects "Mun" instead, no idea why

Thats another Mod? Maybe its simply the pixel offset of teh dropdown menu code or somesuch. Thats for the heads up that will get me close to the right place in the code