Arrowstar

[WIN/MAC/LINUX] KSP Trajectory Optimization Tool v1.6.4 [New Vehicle Sizing Tool!]

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I just noticed something - the rotPeriod for Kerbin in the bodies.ini file I just generated to make sure it wasn't some earlier issue is defined as 21600 - which is the default. I have a MM config for Kopernicus that sets it back to the original period of 21651 (because I hate the sunrise/sunset being at the same time everyday):

@Kopernicus:FINAL
{
  @Body[Kerbin]
  {
    @Properties
    {
      // return Kerbin to old pre-v1.0.5 rotation period
      %rotationPeriod = 21651
    }
  }
}

what's interesting tho is that when I load up LVD with a launch location set to KSC the velocity at rest on the surface is 174.55m/s which is correct (checked against my kOS telemetry data) for a slower rotating Kerbin (the wiki says the default period should have a spin rate of 174.94m/s)

How does this work out properly? I can't find any value of 21651 in the bodies.ini file I'm using

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23 hours ago, Drew Kerman said:

I just noticed something - the rotPeriod for Kerbin in the bodies.ini file I just generated to make sure it wasn't some earlier issue is defined as 21600 - which is the default. I have a MM config for Kopernicus that sets it back to the original period of 21651 (because I hate the sunrise/sunset being at the same time everyday):


@Kopernicus:FINAL
{
  @Body[Kerbin]
  {
    @Properties
    {
      // return Kerbin to old pre-v1.0.5 rotation period
      %rotationPeriod = 21651
    }
  }
}

what's interesting tho is that when I load up LVD with a launch location set to KSC the velocity at rest on the surface is 174.55m/s which is correct (checked against my kOS telemetry data) for a slower rotating Kerbin (the wiki says the default period should have a spin rate of 174.94m/s)

How does this work out properly? I can't find any value of 21651 in the bodies.ini file I'm using

The default rotation period of Kerbin according to the Wiki is 21549.425 seconds, which does correspond to the 174.94 m/s that you have there.  I2f you use 21651 seconds instead, you should be getting 174.12 m/s... which you're not.  I double checked this math in LVD directly.  Here's the relevant block of code:

    rotRateRadSec = 2*pi/bodyInfo.rotperiod;
    omegaRI = repmat([0;0;rotRateRadSec],1,1,numElems);
    vVectECEF = reshape(vVectECEF,3,1,numElems);

    vVectECI = mtimesx(R,(vVectECEF + cross(omegaRI, rVectECEF)));
    vVectECI = reshape(vVectECI,3,numElems);

Basically it takes 2 times pi divided by the rotation period, turns that into a angular rotation rate vector, takes the cross product of that with the position vector (in body fixed coordinates), and then adds that to the body fixed velocity.  When I do this with the 21651 seconds above, I get what I expect, so the math is correct.

I'm going to need to see the MAT file on this one...

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On 10/6/2019 at 10:12 PM, Drew Kerman said:

managed to find some more weird behavior with the SOI search. Take this MAT file for example.

  1. Note end time of Y4 D45, which is an actual future in-game encounter
  2. Change SOI search tolerance to 1E-9
  3. Note end time goes a few million years into the future :P
  4. Change SOI search tolerance to 1E-10
  5. Note end time is now a more reasonable at Y4 D74 however I have already advanced the game past this and can confirm there is no such future encounter
  6. Change SOI search attempts to 3
  7. Note end time is now a few hundred billion years into the future! :P Damn I'm good at breaking things
  8. Change SOI search tolerance down up to 1E-14
  9. Note end time is now Y4 D71 - still no actual encounter there either
  10. Change SOI search tolerance down to 1E-8
  11. Back to proper Y4 D45

So all this came about when I hoped to just set search revs to 100, search attempts to 100 and tolerance to 1E-14 and have a nice catch-all. I guess I shouldn't be surprised to find it's a bit more complicated than that :D I'll just make a habit of doing a manual check via distance graph output and if I see anything being missed I'll narrow down to just that one encounter and tweak around with the search options until I find it

Alright, @Drew Kerman, check out this pre-release. This includes my updated SoI search code for MA.  Note that big parameter that impacts accuracy (and thus CPU time) is "Number of SoI Transition Search Attempts."  I rearranged the menu a bit so it's under a new "SoI Transitions" sub-menu.  In my testing, 1000 seems to be a good number for accuracy for this quantity.  You can increase it to improve the accuracy or decrease it increase runtime speed at the expense of accuracy.

Anyway, feedback requested whenever you get the chance! :)

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10 hours ago, Arrowstar said:

I2f you use 21651 seconds instead, you should be getting 174.12 m/s... which you're not

Well, that's even more bizarre then because the game is calculating it wrong too? kOS and LVD are both giving the same 174.55m/s

10 hours ago, Arrowstar said:

I'm going to need to see the MAT file on this one...

Here you go! It's an LVD case file built from PR7

7 hours ago, Arrowstar said:

Anyway, feedback requested whenever you get the chance! :)

On it, should have a chance to look it over this weekend, thx! Don't forget about the density curve too when you have time

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4 hours ago, Drew Kerman said:

Don't forget about the density curve too when you have time

So here's how KSP models atmospheres as far as I know:

If you look at the temperature curve equations, I do some of that.  I don't compute the SunDotNormalized value (assume is 1) and I don't compute the axialTemperatureSunBiasaxialTemperatureSunMultCurve, or eccentricityTemperatureBiasCurve terms (assume each is 0.0).  Looking back on it, I think I understand why I left these out: there's a lot of CPU time involved in computing the Sun's position, the current true anomaly of the planet, and interpolating on the other curves.

It can be done, but I think we need to make sure that it is absolutely necessary for good results before we do because we're talking a decent hit to in-atmosphere trajectory modeling going down this road.  (I'd also need to add a few new items to the bodies.ini file for each body, but that's not as big of a deal.)  What are your thoughts?

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1 hour ago, Arrowstar said:

What are your thoughts?

I agree that there's not enough data to say for sure that this will show a reasonable improvement. I'll go through some more launches in the coming weeks and analyze more data to continue to weed out other possible causes. We'll revisit this later on down the road

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9 hours ago, Drew Kerman said:

I agree that there's not enough data to say for sure that this will show a reasonable improvement. I'll go through some more launches in the coming weeks and analyze more data to continue to weed out other possible causes. We'll revisit this later on down the road

Alright, well, the question of "just how much performance" bothered me all day, so I actually implemented the rest of the terms in the temperature equation lol. :P Fun fact, it turns out that none of the bodies in stock KSP even use those terms I skipped terms, so what you've got before should basically be spot on.  Well, reasonably close anyway.  But I guess someone could use it in the future for a more realistic Kerbin or whatever, so it's not completely useless.

Anyway!  This new pre-release includes:

  1. The updated atmospheric temperature model;
  2. A new Graphical Analysis "Atmospheric Temperature" task for MA and LVD; and
  3. A new KSPTOTConnect plugin that is required to generate the new bodies.ini file with the new temperature curves in them.

You'll need to use a new bodies.ini file with this new pre-release than what you've been using, because it'll need those new curves, so regenerate your current bodies.ini file with KSPTOT directly after installing the new KSPTOTConnect plugin.

Please let me know how this works for you. :)

EDIT: Found a bug, pulled pre-release.  Will reupload soon.

EDIT: Re-uploaded.  We're all good now :)

EDIT: The performance hit is about 20% more CPU time with the new temperature models enabled, at least on the two-stage to orbit example.  Of course, if most of the trajectory is outside an atmosphere, then this figure will improve.

Edited by Arrowstar

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will check PR9 later today right now I'm using PR8 and the new SOI search works great - I went back to orbital data from before the one I missed and propogated forward and it properly found that one and the future ones I know happen.

However the new default 1000 search attempt setting exacerbates a problem I noticed before but wasn't really that annoying until now - I regularly check asteroid encounters for those I know are crossing a planet's orbit (I see the close approach icons when I target the planet in the map view) and if MA fails to find an encounter in 100 revs I just switch the Coast to Next SOI event to a True Anomaly event, enter 1 for coast revs and re-plot so I get a full orbit. However even though it's only doing one revolution (not 100) it still takes just as long for some reason. I just tried it with an asteroid in orbit near Jool and it took 98.975 seconds for the Next SOI coast and 104.830 seconds for the TA coast of 1 revolution.

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4 hours ago, Drew Kerman said:

However the new default 1000 search attempt setting exacerbates a problem I noticed before but wasn't really that annoying until now - I regularly check asteroid encounters for those I know are crossing a planet's orbit (I see the close approach icons when I target the planet in the map view) and if MA fails to find an encounter in 100 revs I just switch the Coast to Next SOI event to a True Anomaly event, enter 1 for coast revs and re-plot so I get a full orbit. However even though it's only doing one revolution (not 100) it still takes just as long for some reason. I just tried it with an asteroid in orbit near Jool and it took 98.975 seconds for the Next SOI coast and 104.830 seconds for the TA coast of 1 revolution.

So you ran into an edge case where the initial and final true anomalies are the same when you use the Coast to True Anomaly function.  In this case, the code was actually searching all 100 SoI search revs, which is why it took so long to propagate.  I've rectified the issue (hopefully) in KSPTOT v1.6.4 pre-release 10.  Please let me know if you see an improvement. :)

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glad it was an easy fix, thanks.

Okay I took a look at the new density model and it may still need work. I've got the LVD files, bodies file and excel analysis here, with plots of density, pressure and temperature by altitude. Let me know if I made a mistake somewhere. If not, then hopefully it helps point towards the problem

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1 hour ago, Drew Kerman said:

glad it was an easy fix, thanks.

Okay I took a look at the new density model and it may still need work. I've got the LVD files, bodies file and excel analysis here, with plots of density, pressure and temperature by altitude. Let me know if I made a mistake somewhere. If not, then hopefully it helps point towards the problem

Yeah, I found a bug in the temperature code that's been there for a while actually... whoops.  Give KSPTOT v1.6.4 pre-release 11 a go.  It should be much closer to what you'd expect.  It's not perfect still, mind, but I'm hopefully it's close enough to be "good enough" for the time being.

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10 minutes ago, Arrowstar said:

It should be much closer to what you'd expect.  It's not perfect still, mind, but I'm hopefully it's close enough to be "good enough" for the time being.

yaaaasss now that looks nice. Have to look forward right now for a while but eventually will go back and do another look at the previous flight to see what effect this has

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Minor cosmetic issue that's hopefully an easy fix - selecting "Show Child Bodies" in the Mission Animator changes the illumination slightly for some reason (not really in a bad way just noticeable) and only seems to show half the child body, at least in the case of Mun which is the only time I've used it so far

FuD9hRz.png

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The tool won't launch for me. Shortly after I try to, I get a (what I'm assuming is) a log file that says "Undefined function or variable 'matlabrc'." It also launched the very first time when I downloaded it, but that was the only time.

I've already reinstalled MATLAB and re-extracted the zip I have, though.

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17 hours ago, WarriorSabe said:

The tool won't launch for me. Shortly after I try to, I get a (what I'm assuming is) a log file that says "Undefined function or variable 'matlabrc'." It also launched the very first time when I downloaded it, but that was the only time.

I've already reinstalled MATLAB and re-extracted the zip I have, though.

Alright, so doing some research, here's what I'd like to suggest you do:

  1. Delete the following folder " C:\Users\[username]\AppData\Local\Temp\[username]\mcrCache[version]"
    1. Where [username] is your Windows username and [version] is "9.3".
  2. Try rerunning KSPTOT.
  3. If that doesn't work, let me know.  Thanks!

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11 minutes ago, Arrowstar said:

Alright, so doing some research, here's what I'd like to suggest you do:

  1. Delete the following folder " C:\Users\[username]\AppData\Local\Temp\[username]\mcrCache[version]"
    1. Where [username] is your Windows username and [version] is "9.3".
  2. Try rerunning KSPTOT.
  3. If that doesn't work, let me know.  Thanks!

That worked, thanks!

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ok, so now that it's working, I have a question: Is it possible to include capture delta-V in the multi-flyby maneuver sequencer? I'm trying to use it to plot gravity assists, but I often get final flybys with very high relative velocities. I know I can limit the excess hyperbolic velocity, but it doesn't seem to be super helpful in that regard.

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15 hours ago, WarriorSabe said:

ok, so now that it's working, I have a question: Is it possible to include capture delta-V in the multi-flyby maneuver sequencer? I'm trying to use it to plot gravity assists, but I often get final flybys with very high relative velocities. I know I can limit the excess hyperbolic velocity, but it doesn't seem to be super helpful in that regard.

It is not possible to include the capture delta-v directly because that depends on the final orbit, and determining the delta-v maneuver from the final inbound trajectory is a whole separate optimization problem.  The best way to limit your capture delta-v is to gradually step up your solar semi-major axis by using flybys of the next lower planet.  Limiting the arrival Vinf will also help, and you can turn off the departure Vinf from the objective function and just limit it if you know roughly what your launch vehicle or spacecraft can do when departing Kerbin.

I can help more if you show me a screenshot of your MFMS window. :)

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47 minutes ago, Arrowstar said:

It is not possible to include the capture delta-v directly because that depends on the final orbit, and determining the delta-v maneuver from the final inbound trajectory is a whole separate optimization problem.  The best way to limit your capture delta-v is to gradually step up your solar semi-major axis by using flybys of the next lower planet.  Limiting the arrival Vinf will also help, and you can turn off the departure Vinf from the objective function and just limit it if you know roughly what your launch vehicle or spacecraft can do when departing Kerbin.

I can help more if you show me a screenshot of your MFMS window. :)

Well, this is about what I get when I set the limits to roughly what a straight Hohmann transfer gets (this isn't the stock system, as you can see):

 OYSHuNm.png

If I don't set limits or uncheck one of them, I get something even worse. This is actually one of the better ones, and the total delta-V without the capture is still the same as both ends of a straight transfer. Both intermediate planets are rather massive. Also, the second gravity assist goes through the planet.

I'm trying to figure out how much delta-V this would take, so I don't have a vessel designed.

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7 minutes ago, WarriorSabe said:

Well, this is about what I get when I set the limits to roughly what a straight Hohmann transfer gets (this isn't the stock system, as you can see):

 OYSHuNm.png

If I don't set limits or uncheck one of them, I get something even worse. This is actually one of the better ones, and the total delta-V without the capture is still the same as both ends of a straight transfer. Both intermediate planets are rather massive. Also, the second gravity assist goes through the planet.

I'm trying to figure out how much delta-V this would take, so I don't have a vessel designed.

Okay, thanks.  Can you provide me with the rest of the user interface too?  I need to see how you've got it set up so I can see what's going wrong.  Thanks! :)

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11 minutes ago, Arrowstar said:

Okay, thanks.  Can you provide me with the rest of the user interface too?  I need to see how you've got it set up so I can see what's going wrong.  Thanks! :)

WWT9FYG.png

I had already tried other ones, so that's why this one is different. It also has even more delta-V than the last one.

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1 minute ago, WarriorSabe said:

WWT9FYG.png

I had already tried other ones, so that's why this one is different. It also has even more delta-V than the last one.

Okay, so not stock KSP.  Can you post your bodies.ini file that you're using?  I'll load it in and see what I come up with.  I'll also need some information about your waypoints (the names of bodies and the min and max flight times).  Thanks!

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2 minutes ago, Arrowstar said:

Okay, so not stock KSP.  Can you post your bodies.ini file that you're using?  I'll load it in and see what I come up with.  I'll also need some information about your waypoints (the names of bodies and the min and max flight times).  Thanks!

Here: https://www.dropbox.com/s/stczmc39qbhqj6o/endoftime.ini?dl=0. It's actually a planet pack I'm currently working on, so that's why you might see that it's somewhat sparse. I didn't care about the flight times, and you I was trying a path with flybys of Cerberus and Tempest to get to Revenant

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16 minutes ago, WarriorSabe said:

Here: https://www.dropbox.com/s/stczmc39qbhqj6o/endoftime.ini?dl=0. It's actually a planet pack I'm currently working on, so that's why you might see that it's somewhat sparse. I didn't care about the flight times, and you I was trying a path with flybys of Cerberus and Tempest to get to Revenant

I think part of the issue is that you are going down very deep into the solar gravity well.  I suspect this mission sequence (Kerbin -> Cerb. -> Tempest -> Rev.) isn't viable.  I played around with a number of launch windows and this was the best I found:

Hyperbolic Departure & Flyby Orbits
---------------------------------------------
Hyperbolic Departure Orbit from Kerbin
---------------------------------------------
Semi-major Axis =               -1194.4900 km
Eccentricity =                  1.669741849
Inclination =                   0.9026 deg
Right Ascension of AN =         241.6813 deg
Argument of Periapse =          359.9713 deg
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  8.4468 deg
Out. Hyp. Vel. Vect Declin. =   0.7231 deg
Out. Hyp. Vel. Magnitude =      1.645167460 km/s
---------------------------------------------
Inbound Hyperbolic Flyby Orbit to Cerberus
---------------------------------------------
Semi-major Axis =               -1283.7331 km
Eccentricity =                  2.173269321
Inclination =                   179.7915 deg
Right Ascension of AN =         176.8907 deg
Argument of Periapse =          90.7452 deg
Periapse Radius =               1506.1646 km
---------------------------------------------
Outbound Hyperbolic Flyby Orbit from Cerberus
---------------------------------------------
Semi-major Axis =               -720.1869 km
Eccentricity =                  3.0914
Inclination =                   179.7915 deg
Right Ascension of AN =         176.8907 deg
Argument of Periapse =          90.7452 deg
Periapse Radius =               1506.1646 km
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  -22.7280 deg
Out. Hyp. Vel. Vect Declin. =   -0.0700 deg
Out. Hyp. Vel. Magnitude =      4.678249801 km/s
---------------------------------------------
Inbound Hyperbolic Flyby Orbit to Tempest
---------------------------------------------
Semi-major Axis =               -339.0596 km
Eccentricity =                  11.471947281
Inclination =                   178.4609 deg
Right Ascension of AN =         312.8840 deg
Argument of Periapse =          261.5711 deg
Periapse Radius =               3550.6145 km
---------------------------------------------
Outbound Hyperbolic Flyby Orbit from Tempest
---------------------------------------------
Semi-major Axis =               -339.0372 km
Eccentricity =                  11.4726
Inclination =                   178.4609 deg
Right Ascension of AN =         312.8840 deg
Argument of Periapse =          261.5711 deg
Periapse Radius =               3550.6145 km
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  -43.6888 deg
Out. Hyp. Vel. Vect Declin. =   -0.0920 deg
Out. Hyp. Vel. Magnitude =      10.776517402 km/s
---------------------------------------------
Inbound Hyperbolic Orbit to Revenant
---------------------------------------------
Inb. Hyp. Vel. Vect Rt. Asc. =  -62.9966 deg
Inb. Hyp. Vel. Vect Declin. =   -0.2271 deg
Inb. Hyp. Vel. Magnitude =      7.3009 km/s



Sun-Centric Transfer Orbits
---------------------------------------------
Phase 1 Transfer Orbit (Kerbin -> Cerberus)
---------------------------------------------
Semi-major Axis =             4733408.7843 km
Eccentricity =                  0.385647947
Inclination =                   0.2010 deg
Right Ascension of AN =         106.6816 deg
Argument of Periapse =          176.3870 deg
Period =                     3349787.4312 sec
Departure True Anomaly =        183.6130 deg
Arrival True Anomaly =          110.7691 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Phase 2 Transfer Orbit (Cerberus -> Tempest)
---------------------------------------------
Semi-major Axis =             2919112.6712 km
Eccentricity =                  0.702894161
Inclination =                   0.2030 deg
Right Ascension of AN =         142.6789 deg
Argument of Periapse =          84.6158 deg
Period =                     1622305.0394 sec
Departure True Anomaly =        166.5432 deg
Arrival True Anomaly =          107.4057 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Phase 3 Transfer Orbit (Tempest -> Revenant)
---------------------------------------------
Semi-major Axis =             2079356.7442 km
Eccentricity =                  0.693896594
Inclination =                   0.0534 deg
Right Ascension of AN =         27.0685 deg
Argument of Periapse =          180.0217 deg
Period =                      975325.8572 sec
Departure True Anomaly =        127.6101 deg
Arrival True Anomaly =          0.1129 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Kerbin Departure Date = 
                 Year 2, Day 39 22:11:05.562
                      (34899065.5620 sec UT)
Cerberus Arrival Date = 
                 Year 2, Day 65 14:14:17.214
                      (37116857.2135 sec UT)
Tempest Arrival Date = 
                 Year 2, Day 79 00:15:46.018
                      (38276146.0180 sec UT)
Revenant Arrival Date = 
                 Year 2, Day 88 23:20:45.424
                      (39136845.4243 sec UT)
---------------------------------------------
Total Mission Duration = 
                        49 Days 01:09:39.862



DV Maneuver Information

---------------------------------------------
Burn Information to Depart Kerbin
---------------------------------------------
Total Delta-V =                 1.2750 km/s
Prograde Delta-V =              1273.9776 m/s
Orbit Normal Delta-V =          51.7415 m/s
Radial Delta-V =                1.0287 m/s
---------------------
Burn True Anomaly =             241.6813 deg
---------------------------------------------
Burn Information to Depart Cerberus
---------------------------------------------
Total Delta-V =                 0.7807 km/s
Prograde Delta-V =              780.7330 m/s
Orbit Normal Delta-V =          -0.0000 m/s
Radial Delta-V =                -0.0002 m/s
---------------------
Burn True Anomaly =             0.0000 deg
---------------------------------------------
Burn Information to Depart Tempest
---------------------------------------------
Total Delta-V =                 0.0003 km/s
Prograde Delta-V =              0.3270 m/s
Orbit Normal Delta-V =          0.0000 m/s
Radial Delta-V =                -0.0000 m/s
---------------------
Burn True Anomaly =             0.0000 deg
---------------------------------------------
Total Mission Delta-V =         2.0561 km/s

Keep in mind that the solver in MFMS is nondeterministic, so you may have to run it a few times.

I would try different sequences of waypoints.  Maybe Kerbin -> Cerberus -> Cerberus -> Rev.  Do a bit of exploration of the problem. :)

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39 minutes ago, Arrowstar said:

I think part of the issue is that you are going down very deep into the solar gravity well.  I suspect this mission sequence (Kerbin -> Cerb. -> Tempest -> Rev.) isn't viable.  I played around with a number of launch windows and this was the best I found:


Hyperbolic Departure & Flyby Orbits
---------------------------------------------
Hyperbolic Departure Orbit from Kerbin
---------------------------------------------
Semi-major Axis =               -1194.4900 km
Eccentricity =                  1.669741849
Inclination =                   0.9026 deg
Right Ascension of AN =         241.6813 deg
Argument of Periapse =          359.9713 deg
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  8.4468 deg
Out. Hyp. Vel. Vect Declin. =   0.7231 deg
Out. Hyp. Vel. Magnitude =      1.645167460 km/s
---------------------------------------------
Inbound Hyperbolic Flyby Orbit to Cerberus
---------------------------------------------
Semi-major Axis =               -1283.7331 km
Eccentricity =                  2.173269321
Inclination =                   179.7915 deg
Right Ascension of AN =         176.8907 deg
Argument of Periapse =          90.7452 deg
Periapse Radius =               1506.1646 km
---------------------------------------------
Outbound Hyperbolic Flyby Orbit from Cerberus
---------------------------------------------
Semi-major Axis =               -720.1869 km
Eccentricity =                  3.0914
Inclination =                   179.7915 deg
Right Ascension of AN =         176.8907 deg
Argument of Periapse =          90.7452 deg
Periapse Radius =               1506.1646 km
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  -22.7280 deg
Out. Hyp. Vel. Vect Declin. =   -0.0700 deg
Out. Hyp. Vel. Magnitude =      4.678249801 km/s
---------------------------------------------
Inbound Hyperbolic Flyby Orbit to Tempest
---------------------------------------------
Semi-major Axis =               -339.0596 km
Eccentricity =                  11.471947281
Inclination =                   178.4609 deg
Right Ascension of AN =         312.8840 deg
Argument of Periapse =          261.5711 deg
Periapse Radius =               3550.6145 km
---------------------------------------------
Outbound Hyperbolic Flyby Orbit from Tempest
---------------------------------------------
Semi-major Axis =               -339.0372 km
Eccentricity =                  11.4726
Inclination =                   178.4609 deg
Right Ascension of AN =         312.8840 deg
Argument of Periapse =          261.5711 deg
Periapse Radius =               3550.6145 km
---------------------
Out. Hyp. Vel. Vect Rt. Asc. =  -43.6888 deg
Out. Hyp. Vel. Vect Declin. =   -0.0920 deg
Out. Hyp. Vel. Magnitude =      10.776517402 km/s
---------------------------------------------
Inbound Hyperbolic Orbit to Revenant
---------------------------------------------
Inb. Hyp. Vel. Vect Rt. Asc. =  -62.9966 deg
Inb. Hyp. Vel. Vect Declin. =   -0.2271 deg
Inb. Hyp. Vel. Magnitude =      7.3009 km/s



Sun-Centric Transfer Orbits
---------------------------------------------
Phase 1 Transfer Orbit (Kerbin -> Cerberus)
---------------------------------------------
Semi-major Axis =             4733408.7843 km
Eccentricity =                  0.385647947
Inclination =                   0.2010 deg
Right Ascension of AN =         106.6816 deg
Argument of Periapse =          176.3870 deg
Period =                     3349787.4312 sec
Departure True Anomaly =        183.6130 deg
Arrival True Anomaly =          110.7691 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Phase 2 Transfer Orbit (Cerberus -> Tempest)
---------------------------------------------
Semi-major Axis =             2919112.6712 km
Eccentricity =                  0.702894161
Inclination =                   0.2030 deg
Right Ascension of AN =         142.6789 deg
Argument of Periapse =          84.6158 deg
Period =                     1622305.0394 sec
Departure True Anomaly =        166.5432 deg
Arrival True Anomaly =          107.4057 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Phase 3 Transfer Orbit (Tempest -> Revenant)
---------------------------------------------
Semi-major Axis =             2079356.7442 km
Eccentricity =                  0.693896594
Inclination =                   0.0534 deg
Right Ascension of AN =         27.0685 deg
Argument of Periapse =          180.0217 deg
Period =                      975325.8572 sec
Departure True Anomaly =        127.6101 deg
Arrival True Anomaly =          0.1129 deg
Num. Full Revs Prior to Arrival = 0.0000
---------------------------------------------
Kerbin Departure Date = 
                 Year 2, Day 39 22:11:05.562
                      (34899065.5620 sec UT)
Cerberus Arrival Date = 
                 Year 2, Day 65 14:14:17.214
                      (37116857.2135 sec UT)
Tempest Arrival Date = 
                 Year 2, Day 79 00:15:46.018
                      (38276146.0180 sec UT)
Revenant Arrival Date = 
                 Year 2, Day 88 23:20:45.424
                      (39136845.4243 sec UT)
---------------------------------------------
Total Mission Duration = 
                        49 Days 01:09:39.862



DV Maneuver Information

---------------------------------------------
Burn Information to Depart Kerbin
---------------------------------------------
Total Delta-V =                 1.2750 km/s
Prograde Delta-V =              1273.9776 m/s
Orbit Normal Delta-V =          51.7415 m/s
Radial Delta-V =                1.0287 m/s
---------------------
Burn True Anomaly =             241.6813 deg
---------------------------------------------
Burn Information to Depart Cerberus
---------------------------------------------
Total Delta-V =                 0.7807 km/s
Prograde Delta-V =              780.7330 m/s
Orbit Normal Delta-V =          -0.0000 m/s
Radial Delta-V =                -0.0002 m/s
---------------------
Burn True Anomaly =             0.0000 deg
---------------------------------------------
Burn Information to Depart Tempest
---------------------------------------------
Total Delta-V =                 0.0003 km/s
Prograde Delta-V =              0.3270 m/s
Orbit Normal Delta-V =          0.0000 m/s
Radial Delta-V =                -0.0000 m/s
---------------------
Burn True Anomaly =             0.0000 deg
---------------------------------------------
Total Mission Delta-V =         2.0561 km/s

Keep in mind that the solver in MFMS is nondeterministic, so you may have to run it a few times.

I would try different sequences of waypoints.  Maybe Kerbin -> Cerberus -> Cerberus -> Rev.  Do a bit of exploration of the problem. :)

I don't think it responds well to two consecutive assists of the same planet, but the maneuver you got was definitely better than any of the ones I got. What settings did you use?

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