Jump to content

My First Elkano Challenge: Minmus (1.3 Stock Craft / Mods) Sept/Oct 2017


scottadges

Recommended Posts

So here I go... My first Elkano Challenge

Going to Minmus, since I've heard that's a bit easier to manage on the first one. I'll be keeping notes with progress on the challenge, along with screenshots from key parts of the mission.

For reference, here is the thread for the Elkano Challenge, including the rules to complete this one.

Edited by scottadges
Link to comment
Share on other sites

GETTING STARTED: 

I started like any other adventure in KSP: I designed a spacecraft.

In this case, a rover that was capable of traversing Minmus. It needed to be maneuverable with a minimum of weight. It needed a decent amount of fuel, but most importantly, it needed to be refuelable. I planned around an ISRU (the engine bit under the radiator) and two small drills.

QwwsL5x.jpg

Propulsion was important, but had to use the minimum amount of fuel. While the LV-1R mini jets used considerably less fuel than larger 24-77 Twitch jets, the thrust was way less. After some extensive testing, including a test-run mission to Minmus, I decided to make some refinements.

Hence, the Mk1A was the final craft for this Minmus Elkano Challenge attempt:

NxYPOTh.jpg

STATS:

  • Mass: 17,763kg
  • DV: 608m/s
  • TWR: 0.16

EQUIPMENT

  • 1x SPW 3x2 Solar panel
  • 4x PB-NUK RTGs
  • Convert-o-tron 125
  • 2x 24x77 Twitch LFO engines
  • 4x Radial Ore tanks
  • 2x Drill-o-matic drills
  • 4x Small Radiator Panels
  • 6x TR-2L Rugged Wheels

RESOURCES

  • E/C: 2055
  • MP: 727
  • Ore: 300
  • LF: 351
  • Ox: 429
Edited by scottadges
Link to comment
Share on other sites

LAUNCH & TRANSFER TO MINMUS: 

The launch of the Mk1A is complete with the Drop Carrier (Disposable) sitting comfortably in orbit around Minmus!

1bn3VXT.jpg

Actually got there with fuel remaining in the Transfer Stage. I'll keep that attached to change inclination so the craft is on a perfect equatorial orbit. Time to prep for the Drop Carrier descent.

Captured a few nice screenshots along the way:

3r2ffmj.jpg

uxiyJjB.jpg

ShNuJTj.jpg

pFOKQGW.jpg


Check out the step-by-step of the Launch here:

Spoiler

oZjGhtr.jpg
VJoXg7Q.jpg
21JtxPm.jpg
P9RExjq.jpg
MSyuHSw.jpg
3r2ffmj.jpg
VZ9n08I.jpg
ilRCCAA.jpg
H8T1bLT.jpg
P4hqtqd.jpg
yAxZg2q.jpg
TXhAsjj.jpg
vrdolLe.jpg
IErBUe1.jpg
LL3A4zv.jpg
VObg2rT.jpg
8tBb0PV.jpg
3GAiQUF.jpg
le6fFqn.jpg
eb0tyZV.jpg
eOq0zoc.jpg
jpUm0oD.jpg
uxiyJjB.jpg
kx0Vr2v.jpg
qabAIQj.jpg
2Y4j9gK.jpg
ShNuJTj.jpg
8jmOpS2.jpg
pFOKQGW.jpg
kCA3cc6.jpg
7DncNNp.jpg
1Vo2XL9.jpg
ZUzXk7F.jpg
c77SpQ8.jpg
1bn3VXT.jpg
osVcPoU.jpg

Behind-the-scenes building out the Launch Stage:

Spoiler

FJZoqvF.jpg
RPjdwLg.jpg

 

Edited by scottadges
Link to comment
Share on other sites

Landing the Drop Carrier: 

After looking around for landing sites, I finally got an area that was flat enough along my equatorial path. I may go back and re-run that part of the mission, because the descent screenshots were actually terrible.

Basically, I didn't realize that the axes of control would be so off-center. The problem was the probe core was placed vertically in the VAB. But the thrusters were horizontal to the Drop Carrier itself, intended to provide balanced thrust while descending. But that meant, when trying to de-orbit and then land, the probe core was controlling the thrusters along the wrong axis.

Nevertheless, I got it down in one piece... although, at one point, it rolled over in mid-air. Yet it was saved! And no damage!

dvIeOOd.jpg

This was probably a bit over-designed for what was actually necessary to land on Minmus. But I wanted it to look cool! And also be balanced (which didn't end up mattering... given the probe core / thruster problem).

HxI5iZM.jpg

With the legs raised up again, the Mk1A itself is just slightly off the ground. Luckily, that truss from the fairing doesn't actually get in the way. The rover settled nicely to the surface once decoupled.

3krpyG2.jpg

With the Mk1A disembarked from the Drop Carrier, it was time to dispose of the framework. And why not use all that remaining fuel?Last I saw it, the Drop Carrier was orbiting Kerbol after a hasty exit from Kerbin SOI.

Elkano Minmus Challenge Officially Begins

103ecf8.jpg

And there you have First Flag planted. I noted the date in the game: Year 1 Day 22

This is important (as I've found out in the next phase) when refueling, it actually takes quite a few "days" to run the drills and process the fuel. A lot of fast-forwarding is required. Plus I think UT is based on Kerbin time, and Minmus takes a couple days to orbit, etc.

At the end of this journey, it might take more than a year to do the circumnavigation. (Which is fine, because this is a stand-alone game. Not part of my main Career save. So what is time??)
 

Edited by scottadges
Link to comment
Share on other sites

Re: the time it would take, as far as the travel time itself is concerned, you might be pleasantly surprised, so as long as the EC supply is steady at max throttle. :)  (Source: other Minmus Elcanos. And those ruggedized wheels are pretty decent speed-wise). Under a year of rolling time, most definitely. What's the endurance of the fuel cells on full LFO

But as for refueling, I guess that would be where the real drag on the journey would be (especially if the power's coming only from that 2X3 panel...), how about using a few PB-NUKs to chug things along in the dark? And would an engineer instead of a pilot in the cockpit boost things a little? 

Good luck with the journey either way! :) 

Edited by B-STRK
Link to comment
Share on other sites

Thanks for your comments @B-STRK. I'm not actually using fuel cells, I've got 4 of the PB-NUK's nestled under the real wheel struts.

I'm finding the electric wheels are in fact doing most of the work. Only using the 24-77 Twitch engines to get up to speed (short bursts of LFO) and help with steep inclines. I can cruise at a comfortable 18-20m/s with good control. But getting up over 25-30m/s using wheels & engines... she starts to fly off the surface.

So the refueling thing is now basically a backup, whereas my original thought was to run the Twitch engines at low thrust constantly (needing more refueling). Also, the drills help to steady the rover for flag placement. And full ore containers provide good ballast in the front against the weight of the fuel in the rear.

Anyway, you might be right about an Engineer... I do have 2 in orbit. :)  When I originally thought fuel would be more critical, I put a Refueling Support craft in orbit that has 2 engineers aboard. So maybe my pilot Burberry Kerman might swap out for an experimental Engineer?

Edited by scottadges
Link to comment
Share on other sites

The Journey - Flags 2-13: 

Lots of driving. That's what this challenge is about. When they say in the OP "Not for the faint of heart" that is quite true.

DrDRn6c.jpg

But it can be quite interesting. For me, it's about planning a route around the terrain. In my case, from the very start it was a large mountain. So what do you do? Go around? Nah: Go put a flag on it.

FtnafBN.jpg

It's hard to tell from this screenshot, but this is the mesa at the top of the large mountain. It was actually north of my equatorial route, but rather than drive all the way around... I zig-zagged up the slopes and got to the top.

Otherwise... it's a lot of driving. Alone, on a distant moon. Driving.

g3UpOIG.jpg

 

So you see what milestones lay ahead and where best to plant flags. In this case, it was weaving down through the foothills of the large mountain from Flag 7, cutting through hill passes and into valleys, all the while looking to the flats ahead.

d7hRH4i.jpg

And when you arrive... Flag Time! (Also, saving the game and a prudent quick save before EVA)

NwmYgPA.jpg

 

Finally, here's a view behind-the-scenes. This was my last stop at Flag 8 to harvest Ore and top off the LFO tanks. With fast-forwarding... spent almost 90 days to get back up to 100 across the board. But I'm using less LFO now in the way I drive, so I shouldn't need that as much in the future.

L4gWEFF.jpg

For reference, I am using MechJeb's Utilities to provide stability and prevent Overheats. I also decided to use the Speed Control as a way to maintain consistent throttle. I figured that out after about 4 or 5 flags worth of holding down the "W" key and blowing through 75% of my LFO!

Gp19Afx.jpg

 

Edited by scottadges
Link to comment
Share on other sites

Support System: 

From the beginning, my thinking was that I needed to manage fuel consumption and be able to refuel easily. I designed this refueler craft that could orbit and land when necessary, refuel the Rover, and then go back up to orbit. It carries about 4,000 units of LFO.

xsEJsLW.jpg

The shielded docking ports at the bottom are at exactly the right height to couple with the Mk1A on a level surface. The whole craft is built around this functionality, including the landing legs to allow the rover to pull up underneath it.

FhTgaJk.jpg

As I'm finding now, this refueling craft is less important to the journey. But it is useful to have a craft with ample fuel to be able to provide support should I need it.

The other thing I found during testing was not properly seeing Ore concentrations along my projected route. For that, I would of course need an Orbital Survey Scanner in a polar orbit around Minmus to provide just that support. He doesn't do much, but it looks pretty cool.

aiMcEry.jpg

Edited by scottadges
Link to comment
Share on other sites

Journey Continues - Postcard from Minmus:

The aptly named Burberry "Juan Sebastian" Kerman decided to take a selfie postcard from Minmus for the gang back at KSC.

WISH YOU WERE HERE! (Brought to you by StrutCo)

UgbEPny.jpg(If you can't see it, Kerbin is at the top of the frame. Picture perfect! Didn't realize it until I was editing my thumbnails.)

Edited by scottadges
Link to comment
Share on other sites

Journey Continues - Halfway Point!:

Across the flatlands and up into the hills again. Our explorer takes advantage of seeing Kerbin for now while continuing to plant flags and rejoice on each new milestone.

xHU8ci7.jpg

He also figured out how to take selfies by removing the protective solar shield on his cockpit (aka turning on IVA while in the command seat).

ynHXkv2.jpg

This was a fun milestone: Passing the first flag planted by the Refueler Support craft on scouting missions for the Minmus trip.
8p4DfzY.jpg

Before I realized it... we can come up on the halfway point of the journey! I placed a MJ waypoint equidistant from the starting point so I could mark the moment. This was right at Flag 22 in the Midlands after a very long stretch of flatlands.

WUfrXVh.jpg

i3LVrFP.jpg

xoqSmnK.jpg

A lot more to go! And from the looks of it, pretty mountainous terrain on the other side. I'll be waiting for daybreak before continuing the journey. 

Tanks and ore are full up, so should be able to make good time from here on out.

Edited by scottadges
Link to comment
Share on other sites

Journey Continues - Flags 22-32:

Fast-forwarding to daybreak and I could see the route ahead was rough terrain.

ohm3xKd.jpg

I moved into the hills and made good time skirting along the edge of a large mesa. I decided not to go along the upper, flatter area because at the end of the mesa was a steep cliff.
NfY2Kgw.jpg

Despite running with brakes, the downward sides of the hills were causing a lot of air.
Ini1zcU.jpg

After the hills, the terrain opened up flat for a while but again, a steep cliff. I had been viewing ahead and saw the only sloped part of this was a gorge cut in the side. Still at a decent speed, I had to make sure I began deceleration soon enough so I wouldn't fly through the middle of the gorge. 
d4pOS2X.jpg

Even with the brakes on and the speed control set to zero, the rover wasn't decelerating fast enough. There was just too much momentum. I ended up setting the wheels to reverse direction and provided some power to help slow down, but still ended up in at the lip of the gorge. It may be hard to see, but the shadows show you how steep this actually was.

ujRyItp.jpg

Since I'd been travelling a good bit, I needed to make sure to stop, plant a flag, and save before trying to make the descent.
fGZd9jR.jpg

Which was a good thing, because my first attempt I was going about 14m/s and ended up flying up when I got to the edge. Here you can see, it's a pretty steep grade. The lighter area is completely flat, so this had to be about 45of grade.
zpfLzIG.jpg

After a second attempt at about 6m/s and zagging down around the edge (instead of going straight down the slope) I made it into the flats.

I had realized as I was viewing ahead, that this was the very first landing flag for my Refueler Support craft. This was the first place that I landed on Minmus when planning the Elkano trip.
8kTMvQZ.jpg

A little more than 3/4 of the way complete and almost at the end of this trip. A good bit of flatlands ahead, then more mountains before I return back to the start of this fun journey!
DP7rRHt.jpg

Edited by scottadges
Link to comment
Share on other sites

49 minutes ago, [insert_name_here] said:

How long has the driving part of this mission taken so far in real life? I haven't done any forum challenges before and I thought that the Minmus Elkano challenge would be a good place to start.

For me, it's been about 1-2 hours a night over maybe 4 or 5 nights of actual driving so far.

I'm off today, so I'm trying to finish it up this afternoon, but I'm already hitting my stopping point. For me, doing too long of a stretch in one sitting becomes tedious. So I've been breaking it up, then reviewing screenshots and posting to the thread in between. 

Edited by scottadges
Link to comment
Share on other sites

15 minutes ago, scottadges said:

For me, it's been about 1-2 hours a night over maybe 4 or 5 nights of actual driving so far.

Congrats on your progress so far, and for sticking with it.  Not only good driving but that sky-crane rover delivery system was very well-executed in all respects.

I have never done a wheeled Elcano myself (only by boat) so I greatly admire the patience of those who drive so much.  Especially on such low-gravity places as Minmus, which is my 2nd-least favorite place to drive after Mun.  Long ago, it was sort of an initiation ritual around here to have big dreams of putting a rover on Minmus, then finding out you just flat couldn't drive there at all without an ion engine mounted on top to provide constant downforce :D.  Having adjustable wheel friction has solved that problem, but it's still a hard slog due to the need to go slow on bumpy/hilly terrain in such low gravity.  It almost seems possible to achieve accidental escape velocity with a rover on certain hills :P

 

Link to comment
Share on other sites

1 hour ago, scottadges said:

For me, it's been about 1-2 hours a night over maybe 4 or 5 nights of actual driving so far.

I'm off today, so I'm trying to finish it up this afternoon, but I'm already hitting my stopping point. For me, doing too long of a stretch in one sitting becomes tedious. So I've been breaking it up, then reviewing screenshots and posting to the thread in between. 

I'm doing my second Elcano... I already circumnavigated the Mun, and I'm working on Kerbin, and I do the exact same thing... drive for an hour or two, then shut down, back up my game and take a break,  maybe check what's up on the forum, then go back and drive another hour or two. Otherwise it gets way too tedious... :wink:

Edited by Just Jim
Link to comment
Share on other sites

19 hours ago, Just Jim said:

drive for an hour or two, then shut down, back up my game and take a break,  maybe check what's up on the forum, then go back and drive another hour or two. Otherwise it gets way too tedious... :wink:

Or, just get a small paperweight and tape it to the W key :P 

Link to comment
Share on other sites

1 hour ago, DarkOwl57 said:

Or, just get a small paperweight and tape it to the W key :P 

Only to come back just as the rover trips on a bump. Or one of those terrain tile boundaries. :D Every Elcano can be an adventure if you are open to the journey. (Though yeah, an hour, two tops.)

Edited by B-STRK
Link to comment
Share on other sites

So it's done! (Actually about 2 days ago, but wasn't able to update this post before now)

My first Elkano Challenge on Minmus. Lots of driving, but it was worth it in the end for the sense of accomplishment. Not sure whether I'm going to undertake another one...

Here's Burberry "Juan Sebastian" Kerman taking his final selfie of the trip with the original flag planted on Day 22. The full journey took about 198 total days, but that's due to refueling several times (fast-forwarding time).

vNZ7gdV.jpg

VvhVRek.jpg

Ended up with 41 flags across a mostly-equatorial trip. Had to go around a couple mountains and generally tried to plot a course across the flattest areas.

I have a lot of actual driving pictures, which I might post as a "retrospective" for the whole adventure. Until then, very excited to put the Minmus Elkano badge on my signature!

FQSNsUJ.png

 

Edited by scottadges
Link to comment
Share on other sites

Congrats!  Elcanos do indeed give you a sense of accomplishment and it's well-earned.

If you do another one, I recommend a place with either more gravity (so driving is easier and faster) or more varied scenery (so it's not as monotonous), or both.  

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...