EXTREME ION'ing - because it's not covalent, or very punny.

[Monty_Droppings]

Here you go, did a display for jumpyed:

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How to post Imgur albums:

[jumpyed]

Here you go, did a display for jumpyed:

http://imgur.com/a/MABYO

How to post Imgur albums:

I should make note that the pics from HMM on were after reloading the save.

[SuperBigD60]

http://imgur.com/a/qGEO1

--snip--

I imagine the weeks you spent on this are made worth it to see it having worked

I landed on Gilly with only ions back in .18 by accident (that is, I didn't think it was possible, but MJ said I had a TWR that was greater than 1 so I went for it). If I hadn't used a bunch mods (dubious for this challenge), I'd have to fish the screenshots out of my hard drive.

[jumpyed]

I think my craft might be a bit big, 1012 part count and 104t.

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[Mike the Mechanic]

Hello, can I still put an entry into the challenge?

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I did Laythe, Pol, Bop, Gilly, Minmus, Ike

If I calculated correctly, it amounts to 12000 points.

Edited February 7, 2014 by Mike the Mechanic

[metaphor]

Hello, can I still put an entry into the challenge?

I did Laythe, Pol, Bop, Gilly, Minmus, Ike

If I calculated correctly, it amounts to 12000 points.

Very nice!

[Monty_Droppings]

Hello, can I still put an entry into the challenge?

http://imgur.com/a/njyD3

I did Laythe, Pol, Bop, Gilly, Minmus, Ike

If I calculated correctly, it amounts to 12000 points.

HOLY MOTHER OF GOD. <--first reaction

That lander design is the one I settled on, I've been working on an alternate design where you put the micro landing struts on the pylons, It certainly allows for peace of mind, but the interplanetary burn times suffer.

May I see a craft file? i'd love to try my hand at flying that beast.

[Jasonden]

Ike .

Wow, it looks like you did Ike with ions alone? Or did the Ants help?

[Monty_Droppings]

Wow, it looks like you did Ike with ions alone? Or did the Ants help?

It appears to be ions only.

Good thing Ike is classified as practically impossible.

May need to add an achievement for that.

I proved Ike possible with math a few pages ago.

[Mike the Mechanic]

HOLY MOTHER OF GOD. <--first reaction

That lander design is the one I settled on, I've been working on an alternate design where you put the micro landing struts on the pylons, It certainly allows for peace of mind, but the interplanetary burn times suffer.

May I see a craft file? i'd love to try my hand at flying that beast.

Sure - https://www.dropbox.com/s/9zvyufa3d0x7jd8/Dres%20Challenger.craft

I hope it works and that it is the right craft

Ike is possible with it, but you have to be extremly careful:

First, use 1 to toggle the engines and 2 to fold solar panels.

Second, start in a low orbit. 13 kilometers are the lowest you can do on Ike, with a slightly inclined orbit.

Third, start when your prograde marker and the sunbeams form a 45 to 60 degree angle. Kill as much horizonzal velocity as possible. DO NOT LET YOUR VERTICAL VELOCITY GO OVER 20 m/s! - the lander reacts like a whale.

Fourth - there is a drop-tank. Disable fuel flow from the two integrated fuel tanks, leave the droptank and one of the integrated tanks for drainage. When you have used 350 units of xenon in each tank (700 total), transfer the fuel in the integrated tank and activate the decoupler manually.

Fifth and last: If you break one solar panel, you break all solar panels. This is why you have to hover approximately 2-3 meters above ground and press 2. Leave the engines running, it buys the solar panels time to fold up. I have left 3 solar panels that are not affected by the action group, these never break. You have enough delta v, so do not worry if you pass some unionized gas

I had to try a couple of times, after a while it worked. Takeoff is also pretty hard, you first have to get to a certain altitude before you can burn horizontally - maximum TWR is 1.1!

EDIT: MOVE THE ENGINES OUTWARDS!!!!! I forgot to do that before launch and I regretted it the whole week I spent flying this thing

Edited February 8, 2014 by Mike the Mechanic
Making lives easyer since 1993

[donfede]

Hello, can I still put an entry into the challenge?

http://imgur.com/a/njyD3

I did Laythe, Pol, Bop, Gilly, Minmus, Ike

If I calculated correctly, it amounts to 12000 points.

Nice show Mechanic. I stopped considering Laythe after 24x ant engines. How many did you end up using for that portion ?! May have to give that KSPX mod a peek (or hopefully we'll see more of those parts in 0.24 )...

Curious what people have explored per solar panel arrangements? Looking briefly on the web, RL was exploring flower like arrangements for a while, but as efficiency of solar panels improve efforts in layout appear to be dwindling. My thinking has been to model a snow-flake. Key constraints we have to work with are the 1x 'axle', that ion crafts may spin about (their engine thrust).

launch-on,

kdonfede

[Mike the Mechanic]

It appears to be ions only.

Good thing Ike is classified as practically impossible.

May need to add an achievement for that.

I proved Ike possible with math a few pages ago.

Yes, it is ions only - I used up all the delta v for Laythe. Dres would be possible too I guess, but you have to be a hellishly good pilot - which I am not ...

Nice show Mechanic. I stopped considering Laythe after 24x ant engines. How many did you end up using for that portion ?! May have to give that KSPX mod a peek (or hopefully we'll see more of those parts in 0.24 )...

Curious what people have explored per solar panel arrangements? Looking briefly on the web, RL was exploring flower like arrangements for a while, but as efficiency of solar panels improve efforts in layout appear to be dwindling. My thinking has been to model a snow-flake. Key constraints we have to work with are the 1x 'axle', that ion crafts may spin about (their engine thrust).

launch-on,

kdonfede

I stopped counting at a point where it was well beyond 24 - I reopened the file and came to 88 ants. The key was to drop as much unnecessary weight before takeoff and to do orbital maneuvers with ion engines - which I will never do again, it uses up too much time, even with 4X acceleration. Also, no RCS, and it involved considerable manouvering of the Service Module and some Jetpacking.

BTW. I copied your solar panel arrangement intitally, but then I realized that I did not have enough engines - so I used triple symmetry and replaced the innermost panels with a 2x3 panel - that way I got the most coverage. I left out the horizonzal panels, because they would not provide any electricity when the sun was above the capsule and I badly needed all the electricity I could get, since the craft should have gone to Dres

Edited February 8, 2014 by Mike the Mechanic

[jumpyed]

I have to find the willpower to finish mine, the burn times.....

[donfede]

...

BTW. I copied your solar panel arrangement intially, but then I realized that I did not have enough engines - so I used triple symmetry and replaced the innermost panels with a 2x3 panel - that way I got the most coverage. I left out the horizontal panels, because they would not provide any electricity when the sun was above the capsule ...

Thanks for sharing your craft file. (nudge Monty, if you can share yours )

If we're open to discussion, some items I noticed included:

- no reaction wheels : were you able to maneuver the vessel when loaded with fuel?

- no probe : requiring docking operations to be all performed from 1x vessel!

- no rcs : surprised how the docking operations went without it

- very few batteries : looks like I brought along many more batteries than others

Also curious why you used the fuel lines, and the support struts? Xenon fuel appears to ignore most normal fuel paths (ex: disable crossfeed does not stop xenon from passing). I briefly tried it without the struts, and it seemed ok.

Currently exploring potential flight plans and designs... we'll see if I can squeeze more out of my potato-cpu

regards,

kdonfede

[donfede]

Yes, it is ions only - I used up all the delta v for Laythe. ...

How come you brought along 3x Mk1 Command Pods? I could see maybe using 2x, one for the Laythe lander and another for the ion lander. I hope it was not because of Monty's post:

See above post where i referred to this.

Or TLDR:

All parts must be docked together before leaving 100km kerbin orbit, mothership must still use ION power, each lander docked to the mothership must contain a MK1 capsule and Jeb needs to be EVA'd between each one if you plan to use multiple landers.

I checked (after the fact) with Monty per my sharing the Mk1 between landers, and he was OK with it.

kdonfede

[Mike the Mechanic]

Thanks for sharing your craft file. (nudge Monty, if you can share yours )

If we're open to discussion, some items I noticed included:

- no reaction wheels : were you able to maneuver the vessel when loaded with fuel?

- no probe : requiring docking operations to be all performed from 1x vessel!

- no rcs : surprised how the docking operations went without it

- very few batteries : looks like I brought along many more batteries than others

Also curious why you used the fuel lines, and the support struts? Xenon fuel appears to ignore most normal fuel paths (ex: disable crossfeed does not stop xenon from passing). I briefly tried it without the struts, and it seemed ok.

Currently exploring potential flight plans and designs... we'll see if I can squeeze more out of my potato-cpu

regards,

kdonfede

Regarding my design - yes, I stripped that lander to the bare essentials: No RCS, no landing gear, no parachutes, and no reaction wheels. The torque of the capsule is strong enough to turn the lander pretty fast, since it weighs only 6 tons. In order to avoid having to a) do maneuvers with the capsule and to have two additional docking ports to carry around, I bolted the capsule on the lander. This however made it necessary to have a second capsule on the service module, with a parachute attached. The service module itself has a small probe core, and with the reaction wheels of the capsule, it is easily maneuverable (the only thing the service module did was essentially to store Xenon and turn towards the lander when it approached, and get rendezvous with the laythe lander capsule). The Laythe lander had its own capsule, because I could just leave it behind in orbit, without having to worry where I would attach it - also, I did not have to carry unnecessary weight (Parachutes, docking ports) back into Laythe orbit.

I did not do calculations regarding batteries - it might very well be that they are a better alternative to solar panels, in that they provide the same amount of charge in a fixed period of time with less weight (doubtful though) - if so, this opens a ton of new landing spots, such as moho or the mün.

I can explain the struts: The more parts you have, the more a craft wobbles - except if you strut stuff together. In my case, the lander had almost 200 parts, which makes it pretty decent kraken bait, except for the struts. I added the fuel lines with the drop tank literally minutes before launch, so imagine my surprise in pol orbit, when I realized the fuel lines were useless. Anyway, the fuel lines don't add weight (according to some threads in the forum and reddit), so there was no loss (except in part count).

About docking without RCS: It is possible, especially with very small crafts. I visited every celestial body back in .21, and it involved a lot of orbital construction, orbital rendezvous and fuel transfers. After a while, I started to rely mostly on the Navball instead of RCS - and now I dock without RCS, which saves weight and parts, though it does not look as cool as with rcs-thrusters

If your CPU cannot manage high part counts, I recommend the following mod: http://forum.kerbalspaceprogram.com/threads/38577-0-22-UbioZur-Welding-Ltd-2-0-Playtest-5-Now-In-Game-Tool?highlight=part+welder

It creates a new part out of a selection of parts (works best with fuel tanks and struts) and gives the new part the same significant values (weight, drag etc.) as the selection you welded (it's not a cheat mod) and can reduce your part count significantly. I don't use it, because my CPU can handle crafts up to 500 (with a moderate lag), but I imagine it would make lives easier, especially given the nature of this challenge.

[Monty_Droppings]

I've gotten this dark side Ion lander in the works, its only suitable for Pol and Gilly, but it incorporates 20 PB-NUKs, so it is not very efficient.

I have also been doing some math about the math for a dark side lander with batteries, but this is the basic concept of the idea;

you have your standard lander design, then you have what basically consists of batteries that get dropped off as you descend using asparagus staging, the idea being that after you land in the dark, you can wait until daytime to take off again.

[Mike the Mechanic]

I'd like to see that :0 that would be awesome!

[donfede]

I've gotten this dark side Ion lander in the works, its only suitable for Pol and Gilly, but it incorporates 20 PB-NUKs...

...

you have your standard lander design, then you have what basically consists of batteries that get dropped off as you descend using asparagus staging, the idea being that after you land in the dark, you can wait until daytime to take off again.

Very interesting in multiple ways Monty ! Definitely looking forward to seeing the Dark Side ion craft.

best,

kdonfede

[donfede]

While Monty's pushing ahead exploring ion craft that don't require solar panels , my head is still spinning with 'optimal solar panel layout'. I'm putting out this post to help collect my ideas (which I hope to shape a bit more; constructive input is welcome).

# Goals

The goal of optimal solar panel arrangement is to provide maximum power to ion engines, ideally with the least amount of solar panels (either in part-count, or in mass). The best case scenario is where ion engines can run at maximum throttle all the time.

# Terminology (helping us think and talk in common terms)

http://wiki.kerbalspaceprogram.com/wiki/Terminology#Ship_Orientation

FIXME: add pic w/ terms

# Extreme Ion solar panel designs

• tri arrangement (Monty's Hades 1 , Mike's Xenon Impulse)
  
• 2x T arrangement (bi arrangement?), with some perpendicular (K08ia, jumpyed's Snail Ion)
  
• snow-flake arrangement (Jasonden_craft FIXME: get name)
  
• star arrangement (Lump_craft FIXME: get name)
  
• mono perpendicular plane MPP (metaphor_craft FIXME: get name)
  
• box ( jumpyed's Box craft )
  

# Variables and constraints

There are two main variables/constraints we have to work with.

1) Foremost is the thrust-vector, which is fixed by the intended craft direction. The related variable is the craft ability to rotate about the thrust-vector (ex: using the Q and E keys). I found with my long craft and 2x T design (with a gap), that I could significantly improve electricity generation by rotating to certain positions.

2) We have the additional variable of solar panel arrays rotating around their mounts (except for the OX-STAT panels).

# Observations

Most Extreme Ion craft have a plane of solar panels perpendicular to the thrust-vector. This arrangement works best when the sun is front or aft of the craft. The worst scenario for these craft is when the sun is perpendicular to the thrust-vector (port, starboard, nadir, or zenith). Simplifying possible sun arrangements, the third scenario is when the sun is positioned somewhere in-between the two extremes.

metaphor's Ike lander ion craft flip-flops these extremes, as its solar panel plane is inline with the thrust vector.

Jasonden's solar panel layout can switch between a close approximation to a snow-flake, and a plane (or pair of planes).

The tri arrangement, especially as configured by Mike, appears to be capable of the densest solar panel coverage.

# Example Craft

Below is an ordered listing of craft types in various sun arrangements.

# tri, sun front/aft

http://i.imgur.com/J3sawcW.jpg

http://i.imgur.com/tggwOns.jpg

# tri, sun perpendicular to thrust

http://i.imgur.com/35ocfRF.jpg

# tri, sun in-between

http://i.imgur.com/0wSClC8.png

http://i.imgur.com/p9PQGOS.png

http://i.imgur.com/uVjGP2l.jpg

http://i.imgur.com/gddy4AM.png # note shadow on 1/3 of plane

# 2x T (bi), sun front/aft

http://i.imgur.com/7BIKn4v.png

http://i.imgur.com/9fRjBcl.png

http://i.imgur.com/Uiwo4Fk.png

# 2x T (bi), sun perpendicular to thrust

http://i.imgur.com/8ZKt03q.png

http://i.imgur.com/PscVcnM.png

# 2x T (bi), sun in-between

http://i.imgur.com/KUqToe4.png

http://i.imgur.com/5fnJAJc.png

# snow-flake, sun front/aft

http://i.imgur.com/MKRN9Fs.png

http://i.imgur.com/uVL1b6d.png

# snow-flake, sun perpendicular to thrust

http://i.imgur.com/pGkocsH.png

http://i.imgur.com/hGSKiH8.png

http://i.imgur.com/pw6QRYR.png

# snow-flake, sun in-between

http://i.imgur.com/1ajn7tJ.png # note power generation vs http://i.imgur.com/uVL1b6d.png

http://i.imgur.com/UkJY1DJ.png

# star, sun front/aft

http://i.imgur.com/p2ECTLm.png

# MPP, sun perpendicular to thrust

http://i.imgur.com/kOPFbBM.png

# MPP, sun in-between

http://i.imgur.com/KqXvHT5.png

# Questions

- perpendicular solar panels?

- 'wavy plane' instead of flat plane?

- best way to mitigate shadows cast by craft?

kdonfede

--

"Adding K to every word..."

Edited February 14, 2014 by donfede
WIP; updated jumpyed's craft name

[jumpyed]

*SNIP*

# Questions

- perpendicular solar panels?

- 'wavy plane' instead of flat plane?

- best way to mitigate shadows cast by craft?

kdonfede

--

"Adding K to every word..."

Added 6 photos of my munar encounter to my album.

For solar panels:

http://i.imgur.com/1hpwlyR.png

http://i.imgur.com/jukxH8M.png

http://i.imgur.com/O6iv0vC.png

http://kerbalcrafts.com/crafts/346

For the craft you can swap the big panels for small at a cost of 4 e/s(based on maximums) and massive increase in part count with a weight savings.

Will look at others and give opinions/pros-cons after work.

Edited February 13, 2014 by jumpyed
Removed some of a quote added some craft info.

[Jasonden]

For the craft you can swap the big panels for small at a cost of 4 e/s(based on maximums) and massive increase in part count with a weight savings.

I've always figured that the ultimate ideal would be nothing but cubic-octagonal struts with the cheapest 1-panel OX-STAT panels on them. The cubic octagonals are massless, and the OX-STATs provide the best power-to-mass ratio. However I haven't tried it yet -- this is basically guaranteed to grind your machine to a halt. I wonder if the part count would end up at 1500 or what!

[jumpyed]

Oi don! There are 3 pics of my box craft and the name is Box.

Will be editing this post for my pros/cons.

Star:

1. Pros:
   • Light weight config
     
   • Easy Design
     
   • Low part count
     
   • Easily packaged
     
   • Low likelihood for damage
     

[*]

[*]Cons:

• Low energy provision
  
• Craft shadowing panels
  
• 120-180 degrees of craft alignment unusable due to alignment to the sun(can by reduced/removed with dual star panel alignments and those being angled to the front/back of the craft)
  
• Limited scalibility
  

[*]

TriBranch:

1. Pros:
   • Light weight config
     
   • Easy Design
     
   • Some ability to Scale
     
   • Easily packaged
     
   • Low likelihood for damage
     

[*]

[*]Cons:

• Increased part count
  
• Potential Structural issues
  
• 120-180 degrees of craft alignment unusable due to alignment to the sun, difficult to counteract.
  

[*]

2x T(Branching):

1. Pros:
   • Good Generation
     
   • Low-Medium Weight
     
   • Low-Medium Part Count
     

[*]

[*]Cons:

• Torsion Forces
  
• Potential Structural issues
  
• 120-180 degrees of craft alignment unusable due to alignment to the sun, some simply counteraction available.
  
• Can have turning issues.
  

[*]

Monoplane:

1. Pros:
   • Light weight config
     
   • Easily packaged
     
   • Low likelihood for damage
     

[*]

[*]Cons:

• Difficult to design
  
• Craft shadowing panels
  
• Design issues with energy generation and vector aligns
  
• Limited scalibility
  

[*]

Box:

1. Pros:
   • Good Energy Generation
     
   • No Shadows
     
   • Very Flexible for Thrust Vectors
     

[*]

[*]Cons:

• Difficult Design
  
• Damage issues
  
• Large Footprint
  
• Medium-High Part/Mass
  

[*]

Edited February 24, 2014 by jumpyed

[donfede]

From the wiki and web, we get the basic rocket equation to calculate delta-v :

delta-v = ln(mass_start / mass_end) * Isp * 9.81m/s^2

The above formula works well with any number of the same type of engine. For craft that use different engine types, there is a slightly more elaborate formula to calculate Isp:

Isp = (Thrust1 + Thrust2 + ...) / ( (Thrust1/Isp1) + (Thrust2/Isp2) + ... )

However, I am suspecting that this only works appropriately for engines that use common fuel types (which kind of makes sense, as one would expect mass change to require a ratio of fuel types). When I try above equations on hyrbid ion/ant rockets I get unusually low delta-v results . Until I figure a better way, it seems more accurate to calculate the delta-v of the different engines separately.

Have others explored the maths behind hybrid engine craft, and what did they find?

[Mike the Mechanic]

From the wiki and web, we get the basic rocket equation to calculate delta-v :

delta-v = ln(mass_start / mass_end) * Isp * 9.81m/s^2

The above formula works well with any number of the same type of engine. For craft that use different engine types, there is a slightly more elaborate formula to calculate Isp:

Isp = (Thrust1 + Thrust2 + ...) / ( (Thrust1/Isp1) + (Thrust2/Isp2) + ... )

However, I am suspecting that this only works appropriately for engines that use common fuel types (which kind of makes sense, as one would expect mass change to require a ratio of fuel types). When I try above equations on hyrbid ion/ant rockets I get unusually low delta-v results . Until I figure a better way, it seems more accurate to calculate the delta-v of the different engines separately.

Have others explored the maths behind hybrid engine craft, and what did they find?

Mixed Ion/Liquid vehicles have low delta v because you calculate the delta v for the time the ants and the ions both fire. The rest of the time, you have the ants and fuel tanks as deadweight and only the ions firing, which of course kills your delta v further.

I was thinking of a mixed lander, but the ants would have to fire at the end of the descent, which of course would be the same as a suicide burn - and therefore extremely difficult to execute.