Doing It Artemis Style

[sevenperforce]

With yesterday's bombshell, we now finally have a good picture of what the Artemis Mission might look like!

Only one problem: we still don't know which of the three landing systems will ultimately be selected. That's where you come in. NASA is calling on you to build and launch one of these three landing systems for fun and profit!

Baseline rules: Your landing system must be fly unkerballed to a high Mun orbit (Pe > 1000km) and rendezvous with a capsule containing three Kerbals. You can cheat the capsule there if you like. The landing system must then take the crew down to the surface, land safely, allow EVAs, and then launch back to rendezvous with the capsule so that the crew can return safely to Kerbin. I've set this up so that each of the landers offers the same total number of available points, but you go about getting those points in different ways, so it should be fun no matter how you do it.

DLCs are fine but no modded parts.

Option 1: Kynetics, A Keidos Kompany

• Launches from Kerbin sideways, flies upright - 20 points
• Eight ascent/descent engines - 10 points
• Expends two drop tanks - 15 points
• Able to be reused by attaching new drop tanks (demo only) - 30 points
• Uses dual tall solar panels - 12 points
• Lowest weight of any Option 1 submission - 30 points
• Looks most like render (I judge) - 20 points

Option 2: SpaceK Munar SkarSkip

• Single-stage, launches on a single booster - 20 points
• No monoprop thrusters - 10 points
• Uses nine separate canted-out landing engines - 15 points
• Refueled in orbit - 30 points
• Uses fixed solar panels around a docking port in the nose - 12 points
• Lowest part count of any Option 2 submission - 30 points
• Looks most like render (I judge) - 20 points

Option 2: Kational Team

• Three separate modules assembled in munar orbit - 20 points
• Two engines on the descent stage, one on transfer and one on ascent stage - 10 points
• Capable of landing successfully on only a single engine - 15 points
• All modules launched on the same rocket - 30 points
• Transfer stage remains in low munar orbit to take the crew back to the Earth Return capsule - 12 points
• Physically shortest stack of any Option 3 submission - 30 points
• Looks most like render (I judge) - 20 points

Good luck!

Bonus points (cumulative, all entries):

• Land within 100 km of the south Munar pole - 30 points
• Land on a crater rim - 20 points
• Land at the highest elevation of any entry - 50 points
• Deploy science packages carried on vehicle - 10 points
• Deploy a rover - 20 points
• Lowest dV used to get from trans-munar injection to your "Orion" and then to low lunar orbit (Ap < 20 km) - 35 points
• All reaction wheels disabled - 45 points

Leaderboard:

Spoiler

• @jinnantonix, Kynetics Kompany: 167 points plus outstanding bonuses

 

Edited May 4, 2020 by sevenperforce

[vyznev]

Honestly, the Dynetics lander kind of looks like it was designed in KSP to begin with.  

(Not saying that to disparage the design in any way — I'm just saying that a lot of the parts look kind of familiar.  And mounting the lander sideways inside the fairing during launch feels like a very Kerbal solution, as does the use of disposable drop tanks for extra landing delta-v.)

Edited May 1, 2020 by vyznev

[Rhomphaia]

1 hour ago, vyznev said:

Honestly, the Dynetics lander kind of looks like it was designed in KSP to begin with.  

Yep.   Edit, with a new pic, Lander is complete, will build a launcher, and fly mission later.

Edited May 1, 2020 by Rhomphaia

[KingDominoIII]

Working on Starship atm! I'm pretty sure the nosecone is an omnidirectional antenna, not solar panels.

Edited May 1, 2020 by KingDominoIII

[QF9E]

Cool challenge! I'll do the Dynetics one, as I already made the lander. When I first saw it I simply had to make it. Mine is virtually the same as Rhomphaia's, but I have another idea that I want to try as well.

[vyznev]

I'm also working on a Dynetics-style lander.

[Rhomphaia]

For everyone else making Dynetics style. remember to check your symmetry when attaching to the launch vehicle.

Was zoomed in too far to notice, then wondered why I wasn't going anywhere when i staged.

 

My lander has gone through a few minor changes, but is ready to go. Could I get some clarification as to what is considered a High Mun orbit.

Edited May 1, 2020 by Rhomphaia

[sevenperforce]

2 hours ago, Rhomphaia said:

For everyone else making Dynetics style. remember to check your symmetry when attaching to the launch vehicle.

Was zoomed in too far to notice, then wondered why I wasn't going anywhere when i staged.

My wife just asked me why I burst out laughing.

2 hours ago, Rhomphaia said:

My lander has gone through a few minor changes, but is ready to go. Could I get some clarification as to what is considered a High Mun orbit.

Over 1000 km.

You can determine what orbit for your "Orion" will be best positioned for south pole access AND access from Earth.

To that end, adding another bonus above.

[RealKerbal3x]

I'm working on Starship. Which means I need a fully working tanker variant. It may take a few days

Edited May 2, 2020 by RealKerbal3x

[billbobjebkirk]

21 hours ago, Rhomphaia said:

For everyone else making Dynetics style. remember to check your symmetry when attaching to the launch vehicle.

 

Was zoomed in too far to notice, then wondered why I wasn't going anywhere when i staged.

Real Check Yo' Stagin moment...

 

Also, it's a shame you can't do a halo orbit in game without Principia. Maybe as an extra challenge mode?

Edited May 2, 2020 by billbobjebkirk

[Guest]

No one seems to be doing Kational Team. I will try that one. And is there some patch/reward?

[sevenperforce]

13 minutes ago, billbobjebkirk said:

Also, it's a shame you can't do a halo orbit in game without Principia. Maybe as an extra challenge mode?

It is possible to reproduce a halo orbit in stock using the correct inclination and eccentricity so that you stay just outside of the Mun's SOL at all time. Tough tho.

8 minutes ago, The Doodling Astronaut said:

No one seems to be doing Kational Team. I will try that one. And is there some patch/reward?

I'll put together a kickass patch.

Also note a new bonus......

[Rhomphaia]

Well, I woke up today in more of a building mood than a flying one

Not sure which to use now.

[jinnantonix]

Here is my submission for Option 1: Kynetics, A Keidos Kompany

Scoring

Spoiler

 

• Option 1: Kynetics, A Keidos Kompany

• Launches from Kerbin sideways, flies upright - 20 points  YES
• Eight ascent/descent engines - 10 points YES
• Expends two drop tanks - 15 points YES
• Able to be reused by attaching new drop tanks (demo only) - 30 points YES
• Uses dual tall solar panels - 12 points YES
• Lowest weight of any Option 1 submission - 30 points TBA
• Looks most like render (I judge) - 20 points TBA

• Bonus points (cumulative, all entries):

• Land within 100 km of the south Munar pole - 30 points  YES
• Land on a crater rim - 20 points  YES
• Land at the highest elevation of any entry - 50 points  TBA
• Deploy science packages carried on vehicle - 10 points  YES
• Deploy a rover - 20 points  YES
• Lowest dV used to get from trans-munar injection to your "Orion" and then to low lunar orbit (Ap < 20 km) - 35 points  TBA.
  The key to lowest dV on rendezvous was to (from TLI) aim for direct polar munar orbit by passing over the munar pole  and rendezvous with the Orion with minimal radial burn to match planes.

• All reaction wheels disabled - 45 points  NO - Could have done, requirement added after I started my mission

Here is the Lander fully fueled:  14.339t

 

Design notes:

The Launch attempts to simulate a Vulcan Centaur launch vehicle.  4 x Kickback SRBs, 2 x Mainsail engines (BE-4) and  1 x Skipper engine (RL-10).  After TLI burn the Centaur had 30% fuel remaining.

Doing this simulation gave me some insight into the Dynetics Lander design:

The centre of mass of the craft is only marginally above the engine gimbals.  This made the craft heavily reliant on RCS thrusters to maintain stability.  The craft is VERY sensitive to centre of mass (both pitch and yaw), so IRL I would expect that even crew location in the lander can would be critical.  I envisage that engine thrust across the 8 engines would be computer controlled to compensate for COM changes, including anomalous events like fuel leaks, etc. 

Are engine gimbals even required?  Perhaps rely entirely on RCS for craft stability?  Reaction wheels and gimbals offered poor capability, so maybe give up weight for more RCS fuel.  Makes thruster fuel usage critical to mission success.

Depending on requirement, the RCS thruster limit needed to be reset.  Craft rotation needed only 1% of thrust (any more was a waste of fuel) , whereas adjustments during landing needed 100%.

Gimbals would be more effective if they were slung lowered on the craft, further from COM.  I couldn't do that and still deploy the rover which needed to clear the engines.  

Needed to use the large solar arrays during flight to maintain batteries.  Seems unlikely these should be deployed until on the lunar surface, so perhaps some smaller solar panels could be used for during flight.

 

Edited May 4, 2020 by jinnantonix

[vyznev]

I still haven't flown the mission, but instead I ended up rebuilding my lander from scratch because I wanted it to look nicer. I feel like this is starting to look pretty close to the renderings.

(Also, the actual structural linkages are now much less janky, since this time I actually had some idea of where I was going when I started building this version.)

I did fly a couple of test hops at KSC, since this thing actually has enough thrust for it. Like @jinnantonix's version, this one also has some difficulties with attitude and horizontal speed control. I might need to add a few more RCS ports. (The renderings actually show a pair of RCS nozzles above the crew compartment that I haven't included so far.) Landing in full Kerbin gravity can get a bit rough, but at least the core structure is surprisingly durable.  

[sevenperforce]

Great job @jinnantonix! Can I ask how much dV you ended up using to get from TLI to Orion and then down to LLO? 

[billbobjebkirk]

On 5/3/2020 at 7:17 AM, jinnantonix said:

Here is my submission for Option 1: Kynetics, A Keidos Kompany

Wow! Loved the video, that music combined with the polar landing site really made the Mun seem eerie and beautiful.

[jinnantonix]

9 hours ago, sevenperforce said:

Great job @jinnantonix! Can I ask how much dV you ended up using to get from TLI to Orion and then down to LLO? 

My approach to this was to complete TLI with the Centaur on collision with the Mun, then adjusted about 50 m/s to passing over the Mun north pole at about Pe=600km.   For some reason the game wouldn't allow me to do Pe=1000km, the path disappeared at >600km.  Anyway to work around this I just did a small radial adjustment on entering the Mun SOI to increase Pe to 1000km.

I then did two burns. 

1. Near SOI, dV = 104.1 m/s, adjust to encounter.
2. At encounter (over Mun north pole), dV = 139.7m/s

Total dV = 243.8 m/s.

 

7 hours ago, billbobjebkirk said:

Wow! Loved the video, that music combined with the polar landing site really made the Mun seem eerie and beautiful.

The music is courtesy of Kevin McLeod.  He does the theme music for KSP.

[RealKerbal3x]

@sevenperforce Progress...

Starship reentry is hard, but manageable, especially with a plugin like PBW Fuel Balancer that can automatically keep the COM in the desired location. Developing the non-reentry capable Kerbal Landing System variant is going to be much easier.

I should be able to have my entry ready in a day or two  

Edited May 6, 2020 by RealKerbal3x

[ndiver]

On 5/6/2020 at 3:55 PM, RealKerbal3x said:

@sevenperforce Progress...

Starship reentry is hard, but manageable, especially with a plugin like PBW Fuel Balancer that can automatically keep the COM in the desired location. Developing the non-reentry capable Kerbal Landing System variant is going to be much easier.

I should be able to have my entry ready in a day or two  

Note that the Moon Starship is not planned for Earth-reentry, that's why it lost its flaps / wings. Its another vessel (Dragon Crew or Orion) that is used to transport the crew from and back to Earth. The advantage for SpaceX with this situation is that the SuperHeavy does not need to be certified for human transport at this point.

[RealKerbal3x]

21 minutes ago, ndiver said:

Note that the Moon Starship is not planned for Earth-reentry, that's why it lost its flaps / wings. Its another vessel (Dragon Crew or Orion) that is used to transport the crew from and back to Earth. The advantage for SpaceX with this situation is that the SuperHeavy does not need to be certified for human transport at this point.

Yes, I know. The reason why I made the comment about reentry is because while my Munar Starship is not intended for Kerbin return, it needs to be refuelled in orbit, which requires a reentry-capable tanker variant.

I focused quite a bit of the time I had to work on this challenge on making sure my tanker Starship worked properly because I knew that once I had that hard part out of the way, designing the space-only munar lander would be plain sailing

[RealKerbal3x]

@sevenperforce Is it necessary for the lander to enter low Munar orbit before landing or can it drop directly from high orbit to the surface?

Edit: A bit of an update. I managed to get my Starship recreation to high Munar orbit to rendezvous with my Orion, and achieved a successful landing, but then...

I realised that I have ~480m/s of dV left, which isn't enough to get into low Munar orbit, let alone return to the Orion in high orbit. I guess it's time to go back to the drawing board. That's kind of annoying as I only have a couple of hours to play KSP each day, but at least I'll be able to optimise my design and add some things that I forgot initially, like some Breaking Ground surface science experiments.

Sorry for taking so long with this challenge, but I'm going to complete it eventually, no matter how many redesigns and restarts it takes

Edited May 12, 2020 by RealKerbal3x

[sevenperforce]

4 hours ago, RealKerbal3x said:

@sevenperforce Is it necessary for the lander to enter low Munar orbit before landing or can it drop directly from high orbit to the surface?

Edit: A bit of an update. I managed to get my Starship recreation to high Munar orbit to rendezvous with my Orion, and achieved a successful landing, but then...

I realised that I have ~480m/s of dV left, which isn't enough to get into low Munar orbit, let alone return to the Orion in high orbit. I guess it's time to go back to the drawing board. That's kind of annoying as I only have a couple of hours to play KSP each day, but at least I'll be able to optimise my design and add some things that I forgot initially, like some Breaking Ground surface science experiments.

Sorry for taking so long with this challenge, but I'm going to complete it eventually, no matter how many redesigns and restarts it takes

Looks promising!

It's fine to drop straight from high orbit to the pole without LLO circ.

[RealKerbal3x]

55 minutes ago, sevenperforce said:

Looks promising!

It's fine to drop straight from high orbit to the pole without LLO circ.

OK, great. I think I can solve my dV issue with a combination of a couple of extra fuel tanks and higher Isp engines, perhaps Wolfhounds rather than the Skippers it currently has. I'll lose TWR but the increase in dV will most likely make up for it. I only need ~400m/s extra (I'm guessing) for the vehicle to make it back to HMO.

We'll call this mission a test run. The tankers need some work too, they ended up crashing after re-entry due to a lack of fuel. I just have to work the bugs out.

[SlinkyMcman]

On 5/1/2020 at 8:04 AM, sevenperforce said:

DLCs are fine but no modded parts.

 Is ReStock ok?