Chapman Challenge

[Piper]

Only 24 hours left in the challenge, keep up the good work!

 

[Piper]

Ok, the 1st Chapman Challenge is now closed! I will have the results up shortly (in a few hours), and I'll put up a guide on how I did the 90 Antiope mission (that should be up by the weekend). I'll announce the next challenge in one week's time (January 7th), and in the meantime, I'd like to hear a little feedback form people of what they thought of the challenges (ie, too hard/easy, interesting/not interesting, etc.).

and of course...

HAPPY NEW YEAR!!!

 

[tblaxland]

I'd like to hear a little feedback form people of what they thought of the challenges (ie, too hard/easy, interesting/not interesting, etc.).

They at least got me to look at some launch vehicles that I hadn't used before, so that is a good thing.

As for difficulty, I think they were OK. The intermediate challenge was made easier by the existence of LVs that could fly directly to the target so flyby(s) were not required.

I'm still struggling with the advanced challenge, specifically, how to achieve a low enough encounter velocity to get orbit insertion. I just can't work out a flyby, or sequence of flybys, that will do the trick. My latest attempt was to use a V-V-E-Trojan sequence and drag the second stage all the way along to do the insertion burn. Two problems though: I don't think that is a realistic performance option for the second stage; and, I had trouble setting up the second Venus encounter in TransX (in Sling Direct view the closest approach numbers kept oscillating over a large range).

 

[Piper]

They at least got me to look at some launch vehicles that I hadn't used before, so that is a good thing.

As for difficulty, I think they were OK. The intermediate challenge was made easier by the existence of LVs that could fly directly to the target so flyby(s) were not required.

I'm still struggling with the advanced challenge, specifically, how to achieve a low enough encounter velocity to get orbit insertion. I just can't work out a flyby, or sequence of flybys, that will do the trick. My latest attempt was to use a V-V-E-Trojan sequence and drag the second stage all the way along to do the insertion burn. Two problems though: I don't think that is a realistic performance option for the second stage; and, I had trouble setting up the second Venus encounter in TransX (in Sling Direct view the closest approach numbers kept oscillating over a large range).

The key to the advanced one is to set up a single fly-by of Jupiter, and instead of adjusting your outward angle, you adjust your inclination angle (either plus or minus, depending on the trojan you pick). Doing it like this, you can get your encounter velocity down enough that you can orbit it with just the Chapman probe, and not hauling along a booster stage. The only catch is, it takes a while, since after you swing-by Jupiter, you have about 4 years of cruise time.

 

[astrosammy]

A nice tool for slingshots seems to be the "JAQAR Swing-by calculator" (http://www.jaqar.com/). But I'm currently not able to calculate more than one slingshot, and I'm only able to use the 8 Planets (and Pluto). Maybe thats only because of a wrong installation, I'll test it a bit now to find out if it's usable for Orbiter.

 

[tblaxland]

The key to the advanced one is to set up a single fly-by of Jupiter, and instead of adjusting your outward angle, you adjust your inclination angle (either plus or minus, depending on the trojan you pick). Doing it like this, you can get your encounter velocity down enough that you can orbit it with just the Chapman probe, and not hauling along a booster stage. The only catch is, it takes a while, since after you swing-by Jupiter, you have about 4 years of cruise time.

I tried adjusting both outward angle and inclination angle but couldn't find a trajectory that got me any closer than about 250Gm! I guess I need to do more trial and error...

A nice tool for slingshots seems to be the "JAQAR Swing-by calculator" (http://www.jaqar.com/). But I'm currently not able to calculate more than one slingshot, and I'm only able to use the 8 Planets (and Pluto). Maybe thats only because of a wrong installation, I'll test it a bit now to find out if it's usable for Orbiter.

It looks like a handy tool. I've also got GMAT (http://gmat.gsfc.nasa.gov/) sitting on my PC to have a look at.

 

[flytandem]

I went ahead and tried to get a version of Orbiter set up for this challenge. First a generic Orbiter base package and checked with the stock DG to see it was running ok. Then I downloaded all the required zip files as suggested on the Chapman page and placed them into the orbiter folder. Opening the Orbiter launchpad the Chapman scenarios are there but running any of them causes a crash saying critical error and to see the "orbiter.log" file. But there is no such file name. First looking in the Orbiter folder had none and then a search of the computer for that file name gave no result. Vista 64 bit operating system. Any ideas?

This is the file, found it...
**** Orbiter.log
Build Sep 29 2006 [v.060929]
Devices enumerated: 6
Devices accepted: 5
==> RGB Emulation
==> Direct3D HAL
==> Direct3D T&L HAL
==> Direct3D HAL (NVIDIA GeForce 7100 / NVIDIA nForce 630i )
==> Direct3D T&L HAL (NVIDIA GeForce 7100 / NVIDIA nForce 630i )
Found 0 joystick(s)
Module AtlantisConfig.dll [API v.060425]
Module DGConfig.dll [API v.060425]

 

[tblaxland]

Any ideas?

Perhaps a dependency issue? There are some other threads on the forum about needing the Microsoft Visual C run time DLL files for some addons.

 

[flytandem]

The following is a TransX solution to the advanced challenge. It's just the TransX plan for a departure in Oct 2013. All stages are dialed in fairly close showing a transfer to Venus with free coasting slings (no deep space maneuvers) of Venus, then Mars then Earth and arrive Jupiter. I flew it with a stock deltaglider and from low Earth orbit it was just about 4080 m/s deltaV including all MCCs. Not dialed into the TransX plan is a wider pass of Jupiter with slings to Uranus and Neptune. This wasn't in the challenge. Copy paste the bold text below into your Chapman Probe scenario but you will have to change the 4th line of the Left MFD TransX data (the ship name) to that of your ship? I have sure had trouble getting anything other than the stock DG and DGIV to run. Frustrating.

(oh BTW tblaxland was having trouble getting a second sling of Venus to stop oscillating in value... I think it can be caused by the Orbits to Icept value slipping back to 0 from 0.5 , just a thought)

the triple sling to Jupiter scenario... (edit: must use [ame="http://www.orbithangar.com/searchid.php?ID=3039"]TransX 3.13[/ame] !)

BEGIN_DESC
Start Earth on 56591.6 and sling Venus, Mars, Earth then Jupiter.  A wider pass at Jupiter wpould allow sling to Uranus and Neptune.
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 56590.0147171875
END_ENVIRONMENT

BEGIN_FOCUS
  Ship 3
END_FOCUS

BEGIN_CAMERA
  TARGET 3
  MODE Cockpit
  FOV 60.00
END_CAMERA

BEGIN_MFD Left
  TYPE User
  MODE TransX
  Ship  3
  FNumber 9
  Int 1
  Orbit True
  Vector  1064954.60815 5332383.15599 -3319843.78056
  Vector  376.831956254 -30.903772634 71.243765459
  Double  3.98600439969e+014
  Double  56590.0147165
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 0
Plan
0 1
Plan
0 0
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0147165
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Pe Distance
 0  7645212
Ej Orientation
 0  0
Equatorial view
0 0
Finvars
  Finish BaseFunction
  Int 2
  Orbit False
  Handle Sun
  Handle Earth
  Handle Venus
Select Target
 0 Venus
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 1
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 1
Prograde vel.
 0  0
Man. date
 0  56590.0146555
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Prograde vel.
 4  -3786.32444398
Eject date
 3  56591.5999543
Outward vel.
 0  0
Ch. plane vel.
 4  -1382.1753037
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  -3758435041.71 1497821508.77 4694712759.99
  Vector  4717.29379363 -1874.50028198 -5868.73325453
  Double  3.2485863e+014
  Double  56675.0202936
  Handle Venus
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146488
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  -77847825432.2 5494351171.51 73824529403.9
  Vector  -25737.4941493 -495.601781877 -33040.8588643
  Double  1.32712764814e+020
  Double  56684.2254208
  Handle Sun
  Handle Venus
  Handle Mars
Select Target
 0 Mars
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.014642
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Velocity.
 0  0
Outward angle
 4  -0.561731427228
Inc. angle
 4  0.19629648284
Inherit Vel.
0 0
Eject date
 0  56684.2254208
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  4327714894.92 -234044184.747 4462784827.95
  Vector  -8427.41526639 460.462817505 -8701.59048898
  Double  4.28282991638e+013
  Double  57072.982204
  Handle Mars
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146353
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  195345467367 -3039855324.27 83381081341.1
  Vector  -17925.5765477 420.518281153 16631.9370132
  Double  1.32712482783e+020
  Double  57078.9201608
  Handle Sun
  Handle Mars
  Handle Earth
Select Target
 0 Earth
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146286
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 2
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Velocity.
 0  0
Outward angle
 4  -1.92297375018
Inc. angle
 4  0.0321053315904
Inherit Vel.
0 0
Eject date
 0  57078.9201608
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  4105826608.44 -512425836.557 8211239121.42
  Vector  -4722.00392267 590.920704392 -9468.59279938
  Double  3.98600439969e+014
  Double  57718.1620339
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146218
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  40013846547.4 -1945850.19842 141822619689
  Vector  -38873.1888145 244.576388465 3770.21998813
  Double  1.32712838556e+020
  Double  57728.1831717
  Handle Sun
  Handle Earth
  Handle Jupiter
Select Target
 0 Jupiter
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146151
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Velocity.
 0  0
Outward angle
 2  -0.686228555299
Inc. angle
 2  -0.0243647963578
Inherit Vel.
0 0
Eject date
 0  57728.1831717
Finvars
  Finish BaseFunction
  Int 5
  Orbit True
  Vector  477676273118 -19934260666.3 -24902770288.8
  Vector  -6346.41113369 265.01348836 340.293110208
  Double  1.26686534397e+017
  Double  58156.5248013
  Handle Jupiter
  Handle NULL
  Handle NULL
Select Target
 0 None
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 2
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56590.0146083
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Draw Base
0 0
Finvars
  Finish BaseFunction
END_MFD

BEGIN_MFD Right
  TYPE User
  MODE TransX
END_MFD


BEGIN_SHIPS
3:DeltaGlider
  STATUS Landed Earth
  POS -117.2601388 34.0891835
  HEADING 151.05
  RCSMODE 0
  PRPLEVEL 0:1.000 1:1.000
  NAVFREQ 0 524 84 114
  XPDR 6
  GEAR 1 1.0000
  PSNGR 2 3 4
  TRIM 1.000
END
END_SHIPS

BEGIN_ExtMFD
END

-----Post Added-----


Couldn't help it. I had to check if there were other solutions of a sling of the inner to go to Jupiter in the months (years after Jan 1 2011. I found another one and have flown it. It has about 100 m/s more deltaV for the initial transfer than in the scenario pasted in the above post. But has about 500 m/s softer arrival at Jupiter. It leaves 18 months before the above flight and arrives also 18 months ahead making about the same flight time. It launches Earth to sling Venus two times then Earth once followed by going to Jupiter. It uses [ame="http://www.orbithangar.com/searchid.php?ID=3039"]TransX 3.13[/ame]. A scenario package is here. Extract the files into your orbit folder, it should create a subfolder called 2012_EVVEJ in your scenarios folder.:speakcool:

 

[tblaxland]

The following is a TransX solution to the advanced challenge.

I can't run Orbiter at the moment (I'm at work), but it looks like your plan has you orbiting Jupiter in the end. The challenge was to orbit a Jupiter Trojan asteroid...

(oh BTW tblaxland was having trouble getting a second sling of Venus to stop oscillating in value... I think it can be caused by the Orbits to Icept value slipping back to 0 from 0.5 , just a thought)

Thanks, I'll have a look at that.

 

[flytandem]

Thanks. I made an assumption that there were some asteroids orbiting Jupiter and figured that the best start would be to capture at Jupiter first then rendezvous one of the orbiting rocks. Your post had me google trojan asteroid jupiter and I see what it is now. I spent a little while looking at that 41 meg download and have no clue how one goes about placing asteroids in orbiter. Seems I am a lot better at slings than creating files and folders. So I have no way to even start this challenge given that it has both craft and destinations I'm not able to place into Orbiter.


-----Post Added-----


Hmmm... last night I spent about 3 hours trying to get the launch craft running and came up with "Terminating after critical error" and it would CTD with all launch vehicles in the challenge. I was so careful about going slowly and doing what it said to do. Would have no idea how to place a Chapman probe in the craft nor would I have a clue how to even initiate a launch should the craft actually appear to be sitting on the launch pad.

Just now I spent 30 minutes trying to get the asteroids placed so I could at least make a sling navigation plan with a deltaglider to head to an asteroid instead of Jupiter. The readme file in MPCORB Viewer says..."When you start up the program for the first time, it will ask..." Seemed straightforward. I first placed the asteriods in the Orbiter/Texture folder as it said to do. But when I try to run MPC_Database.exe it just comes up with "Component MSINET.OCX or one of its dependencies not correctly registered: a file is missing or invalid."

The challenge it appears (for me at least) has nothing to do with interplanetary navigation, but rather with computer programming and things like unzipping files.

 

[tblaxland]

Hmmm... last night I spent about 3 hours trying to get the launch craft running and came up with "Terminating after critical error" and it would CTD with all launch vehicles in the challenge.

Do you have Vinka's spacecraft3 and multistage2 installed and working with other vessels? Both of these are required (I can't remember if they were specifically called up).

I was so careful about going slowly and doing what it said to do. Would have no idea how to place a Chapman probe in the craft nor would I have a clue how to even initiate a launch should the craft actually appear to be sitting on the launch pad.

Setting up the launch vehicle can be a bit tricky if you are not familiar with Spacecraft3/Multistage3 ini files. When I get a chance to get on my home PC I will post the scenarios/ini/cfg files I used for my launches, hopefully that will help you see what I have done.

For the beginner and intermediate challenges, I used the Soyuz and Ariane 5 from Mustard's site. These were relatively easy to configure for launch. The only change I made was in the guidance files to terminate the autopilot after booster separation. From that point I flew the pitch manually using the PEG routine in Launch MFD.

Just now I spent 30 minutes trying to get the asteroids placed so I could at least make a sling navigation plan with a deltaglider to head to an asteroid instead of Jupiter. The readme file in MPCORB Viewer says..."When you start up the program for the first time, it will ask..." Seemed straightforward. I first placed the asteriods in the Orbiter/Texture folder as it said to do. But when I try to run MPC_Database.exe it just comes up with "Component MSINET.OCX or one of its dependencies not correctly registered: a file is missing or invalid."

msinet.ocx is included in the MPCORB Viewer.zip but you may need to register it (I didn't, but maybe it had already been registered by something else). See here for typical ocx fiule install instructions:
http://www.filegurus.com/cgi-bin/blah/Blah.pl?b=ocxfaq,m=1102052697

BTW, MPC_Database.exe didn't ask me the location of my Orbiter folder. I had to set it by going to File|Change Orbiter Folder. Once I had done that, it exported my asteroid list just fine. No manual editing of any files was required.

As for what the orbit of a Jupiter Trojan looks like, it is very similar to that of Jupiter except that the position of the Trojan is about 60° ahead or behind of Jupiter (depending on which group of Trojans it belongs to). The semi-major axis and eccentricity are very similar. The argument of periapsis was rotated nearly 180° for the one I was looking at (Hektor).

The challenge it appears (for me at least) has nothing to do with interplanetary navigation, but rather with computer programming and things like unzipping files.

Keep posting your questions here, hopefully we can help. We have something to offer each other, after all

 

[flytandem]

Thanks for the help.
I have the spacecraft3.dll and it's in the modules/startup folder. Maybe it's the wrong place.

Getting the launch vehicle running is probably way beyond my ability*interest product. I can't even bother with the extra buttons of the DGIV. Even the stock DG has far more than I would like, for example, why do I have to press "G" to manually raise or lower the gear. It would be easy for it to happen automatically. Same with nose cone opening... just have it open tout-seul when approaching a docking port. How about a ship that you have rot, lin, thrust.... period. Half the time I just sit on a runway however and never launch.... for hours.... just TransXing hypothetical routes around our solar system.

I am really hoping that at least I can have a default DG sitting on a runway somewhere and have it able to see some of those trojan asteroids in the challenge. But that seems as though that may be out of my reach as well.

Question ... If the trojans are installed correctly would TransX be able to show them as a choice after escaping Earth? That would be my hope. And if so... it should be just a matter of an hour or two of toggling the sling options to choreograph an inner planet dance to arrive there with nice light departure and arrival dv. That way maybe I could assist and provide a plan that could be pasted into the scenario for someone wanting to actually launch the Chapman probe but is having trouble knowing the route.

 

[tblaxland]

Thanks for the help.
I have the spacecraft3.dll and it's in the modules/startup folder. Maybe it's the wrong place.

It should be in the Modules folder.

Getting the launch vehicle running is probably way beyond my ability*interest product. I can't even bother with the extra buttons of the DGIV. Even the stock DG has far more than I would like, for example, why do I have to press "G" to manually raise or lower the gear. It would be easy for it to happen automatically. Same with nose cone opening... just have it open tout-seul when approaching a docking port. How about a ship that you have rot, lin, thrust.... period. Half the time I just sit on a runway however and never launch.... for hours.... just TransXing hypothetical routes around our solar system.

One good thing about the Soyuz and Ariane 5 I mentioned is that they have an auto-pilot so that when you are sitting on the pad, just hit 'P' and they will launch, roll, pitch, stage, eject fairing, etc automagically. IMHO, the guidance files need some work as far as getting the pitch program right but then they are probably designed for launching different masses than the Chapman probe. That is why I truncated the guidance at booster sep (PEG doesn't work that well before then anyway).

I am really hoping that at least I can have a default DG sitting on a runway somewhere and have it able to see some of those trojan asteroids in the challenge. But that seems as though that may be out of my reach as well.

I can post a sol.cfg with a couple of trojans in it and the associated asteroid cfgs, so you can drop them into your Orbiter installation.

Question ... If the trojans are installed correctly would TransX be able to show them as a choice after escaping Earth?

Yes, they are. You can select them as a target just like any other planet. I have done so in TransX, but I just haven't been able (or patient enough?) to find a good trajectory.

And if so... it should be just a matter of an hour or two of toggling the sling options to choreograph an inner planet dance to arrive there with nice light departure and arrival dv. That way maybe I could assist and provide a plan that could be pasted into the scenario for someone wanting to actually launch the Chapman probe but is having trouble knowing the route.

An hour or two!?! I've spent many hours so far (much to my wife's chagrin ). Having not used TransX before this challenge didn't help, though...

 

[flytandem]

Thanks again. I'ts refreshing knowing that there are others that like to tinker with trajectories. It seems to be the minority unfortunately.

I switched the spacecraft3.dll into the modules and although it's where it should be, other problems still stop Soyuz from starting up. No worries... my interest now is really on trying to get an asteroid found as a target for TransX.

Getting a sol.cfg file with a Jupiter trojan asteroid to aim at would be great. Actually I could probably place a DG out there with the scenario editor and just target that. The ironic thing is that I had dozens of inner sling plans that all ended up out of phase with Jupiter before I got one close enough that some tweaking of the initial transfer had me hit Jupiter. Might have actually had plans that were bang on for a trojan location that I scrapped.

I was a very slow learner in orbiter but persisted. I have trouble reading detailed instructions. I'm more 3 dimensional in my thinking and can't follow linear trains of info very well. (we all are unique in our own way) I stumbled for days just with trial end error trying to fly orbiter. I spent 6 hours my first day eventually docking with the ISS (DG Mk4 in orbit scenario) using only map and orbit... not even reading the numbers because they meant nothing to me... just doing it graphically what I could make out from what resolution there was visually on each MFD.

I was terribly slow at stumbling through TransX and gave up many times (and restarted) hacking away by trial and error. I couldn't understand the manual at all. I remember the day I realized there was a little green "x" in that target in TransX. What a eureka moment! I had been tinkering with the MFD for weeks before knowing that. But something about making my own 3 dimensional dv plans was mesmerizing.

 

[tblaxland]

I remember the day I realized there was a little green "x" in that target in TransX. What a eureka moment! I had been tinkering with the MFD for weeks before knowing that.

More info please - I don't recall seeing a little green "x"... :blink:


-----Post Added-----

Getting a sol.cfg file with a Jupiter trojan asteroid to aim at would be great.

Here is a zip file containing:

Config\Sol.cfg - this is stock except for the four asteroids in it. The four asteroids are:

Config\90 Antiope.cfg - the asteroid for the intermediate challenge
Config\S2000 90 1.cfg - moon of 90 Antiope
Config\Hektor.cfg - an L4 trojan
Config\Patroclus.cfg - an L5 trojan

Mesh\*various* - mesh files for the above.

http://home.iprimus.com.au/stblaxland/orbiter/Chapman_Challenge_Sol_Files_20090105.zip

I didn't bother with the texture files (asteriod*.dds) since you already have those. Simply extract this zip file into your Orbiter directory. You should be able to fly to any of these in an otherwise stock Orbiter installation.

Let me know if you want the launch vehicle config files. From what you were saying above you will just use a DG for your planning, so I'll just give you some delta-V budgets to work with for different launch vehicles:

To eject from LEO (250km x 250km)
Ariane 5 ECA - 4.5km/s
Delta IVH - 9.8km/s

All other maneouvres:
Chapman Probe - 2.97km/s

Good luck!

 

[flytandem]

It works, Antiope and a couple others show up as a TransX target option. Yeay! Have a broken truck to attend to first but hope to get time to play by tomorrow or Wed.

:speakcool:

edit: and I'll just use the DV limits above to work to stay within and use the stock DG.
thanks!!!


-----Post Added-----


What a fun challenge. I assume that going to Patroclus is what the advanced challenge would be. And to stop there and park or otherwise orbit that rock. Just passing with a flyby is too easy so stopping and staying a while would have to be the challenge.

Given the only dv for the transfer out of LEO and all MCCs plus the braking burn to insert at the asteroid are limited to 4.5 + 2.97 = 7.47 Km/sec it is pretty tight.

The scenario I provided and flew had me use up 4140 of that allowance and it got me to Jupiter. Using Jupiter to both lift the Pe to Patroclus plus do as much plane change as possible had me what appeared to be about 150 m/s short. But there couldn't be much plane change done at jupiter because I arrived at Jupiter where Jupiter was not close to a node with Patroclus.

I think a solution could be to design slings of Venus and Earth to arrive Jupiter at the point where Juipter is crossing the plane of the orbit of Patroclus. Then there would be a chance to do much more of the plane change with the sling. It would still be close. Given spending 4200 or so just getting to Jupiter, it would leave only about 3200 m/s to raise Pe and drop Ap to match Petruclus. I have found a possible setup with Venus Venus Earth Jupiter Patruclus where the Juipter sling is at a node with Patroclus and the resulting orbit would (just using a rough maneuver) shows 800 to raise the Pe then 2200 to drop the Ap. That would supposedly mean a spare 200. And a lot of time since the orbit would probably be about 15 to 20 years for that last synching orbit. If I can get the slings fine tuned (one of then has a pass at 120 Km agl at Earth) I'll post a flight plan. I want to get that Earth pass higher.

 

[tblaxland]

What a fun challenge. I assume that going to Patroclus is what the advanced challenge would be. And to stop there and park or otherwise orbit that rock. Just passing with a flyby is too easy so stopping and staying a while would have to be the challenge.

Yes, the challenge is to orbit one of the Jupiter Trojans. The sol.cfg I gave had one from the leading group and one from the trailing group so you can target whichever is easier.

Given the only dv for the transfer out of LEO and all MCCs plus the braking burn to insert at the asteroid are limited to 4.5 + 2.97 = 7.47 Km/sec it is pretty tight.

Instead of using the dV budget for Ariane 5, you could use the Delta IVH budget (9.8km/s). In both cases the launch vehicle's upper stage can only be used to eject you from LEO because they use cyrogenic propellants and they would boil off by the time you got anywhere else.

If I can get the slings fine tuned (one of then has a pass at 120 Km agl at Earth) I'll post a flight plan. I want to get that Earth pass higher.

That's cutting it pretty fine! Having said that, do you know about aero-gravity assists? I was reading about them recently in this paper:
http://repository.tudelft.nl/consum...electionMethod=latestReleased&dDocName=375329

Very interesting reading. I know there has been discussion on the forum before about using the atmosphere to do plane changes but I never considered using it to boost velocity. But, it seems with the right attitude and lift-drag ratio, it works. Also, according to their website, the Jaqar Swingby Calculator is capable of designing trajectories using them. Of course, the Chapman Probe is not suitable for such a maneouvre but it would work great in a DG!

 

[flytandem]

... do you know about aero-gravity assists?

Yes. I've done some in the DG. TransX can be used to plan and fly it. Basically you start by setting up a gravity assist and if you notice the required height is below the surface of the planet and the planet has an atmosphere, you check the encounter speed. Then you set up the sling by making inherit velocity = "no" and enter an amount of velocity manually that is somewhat less than what the actual encounter speed is. Just a guestimate to approximate the losses due to friction as you fly inverted in the atmosphere. Then as you approach the planet, you aim to hit a flyable height of the atmosphere like 70 Km at Earth or 32 Km at Mars. As you are flying inverted you'll see the required sling height rise you meet you. You'll also see that initially you are faster than the sling speed. You have to seat of the pants try to drag to the required speed at the same time that the sling height meets your height and.... then exit the atmosphere.
Now back to a plan to Patroclus, without aeroslinging.


-----Post Added-----


Ooops, forgot to ask. I noticed that Patroclus is invisible. It's there as a target for TransX but if I'm parked next to it in a DG.... there is nothing visible. Probably missing some file(s).

 

[Piper]

Here's the scenario that I used to do the advanced challenge. You launch aboard an Atlas V (552). The asteroid is called "2001 DZ3" and you will need the [ame="http://www.orbithangar.com/searchid.php?ID=1436"]MPC Database Viewer and Exporter[/ame] to get it. Because there is a space in the name, you will need to re-target 2001 DZ3 once you start it up.

BEGIN_DESC
Launch Chapman 11, onboard a Atlas 552, to the Jupiter Trojan "2001 DZ3."  Swing-by Jupiter to get to it and put yourself into orbit around it.
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 56548.0
END_ENVIRONMENT

BEGIN_FOCUS
  Ship AtlasV
END_FOCUS

BEGIN_CAMERA
  TARGET AtlasV
  MODE Extern
  POS 2.89 0.74 -110.96
  TRACKMODE TargetRelative
  FOV 50.00
END_CAMERA

BEGIN_HUD
  TYPE Surface
END_HUD

BEGIN_MFD Left
  TYPE User
  MODE TransX
  Ship  AtlasV
  FNumber 5
  Int 1
  Orbit True
  Vector  -426743.233887 561750.259876 6331855.55079
  Vector  -407.288349399 12.3835630616 -28.548348215
  Double  3.98600439969e+014
  Double  56548.5062234
  Handle Earth
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 0
Plan
0 1
Plan
0 0
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56548.5008306
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Pe Distance
 0  7645212
Ej Orientation
 0  0
Equatorial view
0 0
Finvars
  Finish BaseFunction
  Int 2
  Orbit False
  Handle Sun
  Handle Earth
  Handle Jupiter
Select Target
 0 Jupiter
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 1
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 1
Prograde vel.
 0  0
Man. date
 0  56548.5062228
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Prograde vel.
 3  8851.12566605
Eject date
 2  56549.3637535
Outward vel.
 1  -52
Ch. plane vel.
 2  -4907.49699718
Finvars
  Finish BaseFunction
  Int 4
  Orbit True
  Vector  106272967407 73898203703.5 -459472876950
  Vector  -1475.0088995 -944.483072585 6302.20562387
  Double  1.26686534397e+017
  Double  56503.8546408
  Handle Jupiter
  Handle NULL
  Handle NULL
Select Target
 0 Escape
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 1
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56548.5058109
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
View Orbit
0 0
Finvars
  Finish BaseFunction
  Int 3
  Orbit True
  Vector  -757003234231 10980448233.5 314606359898
  Vector  -4177.80899152 -5715.35712755 -8877.56410135
  Double  1.32839126489e+020
  Double  57331.9866691
  Handle Sun
  Handle Jupiter
  Handle 2001 DZ3
Select Target
 0 2001 DZ3
Autoplan
0 0
Plan type
0 2
Plan
0 0
Plan
0 0
Plan
0 2
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 0
Prograde vel.
 0  0
Man. date
 0  56548.5062228
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 2
Advanced
0 0
Velocity.
 0  0
Outward angle
 1  -0.0834267382449
Inc. angle
 2  2.02915469496
Inherit Vel.
0 0
Eject date
 0  57331.9866691
Finvars
  Finish BaseFunction
  Int 5
  Orbit False
  Handle 2001 DZ3
  Handle NULL
  Handle NULL
Select Target
 0 None
Autoplan
0 0
Plan type
0 1
Plan
0 0
Plan
0 2
Plan
0 0
Select Minor
 0 None
Manoeuvre mode
0 0
Base Orbit
0 1
Prograde vel.
 0  0
Man. date
 0  56548.5058491
Outward vel.
 0  0
Ch. plane vel.
 0  0
Intercept with
0 0
Orbits to Icept
0 0
Graph projection
0 0
Scale to view
0 0
Advanced
0 0
Draw Base
0 0
Finvars
  Finish BaseFunction
END_MFD

BEGIN_MFD Right
  TYPE User
  MODE TransX
END_MFD

BEGIN_SHIPS
AtlasV:MultistageMultistage2
  STATUS Landed Earth
  BASE LC41:1
  HEADING 90.00
  FUEL 1.000
  CONFIG_FILE ConfigATLASV500_SeriesDual_Engine_CentaurShort_FairingAV552_Chapman.ini
  CONFIGURATION 0
  CURRENT_BOOSTER 1
  CURRENT_STAGE 1
  CURRENT_PAYLOAD 1
  FAIRING 1
END
END_SHIPS

The key for picking a good Trojan to orbit, is to pick a "leading" Trojan, one that is 60deg ahead of Jupiter as opposed to following it. Also, you need to swing-by Jupiter along one of the Trojan's nodes, otherwise the Trojan won't be there when you come back around the sun.