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Elcano Mission - Dolomedes Triton


Maverick_aus

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ELCANO CHALLENGE - ACCEPTED

Prologue

_______________________________________

Many intrepid adventurers have set out to explore the solar system, only a few have attempted to drive or float their way around the entire home planet. Well, perhaps rashly, perhaps ignorantly, I'd like to try. 

I received much pleasure from reading others' attempts at this, successful and otherwise and hats off to you, I have great admiration for your achievement. I'm not a patient or faithful person. So I'm concerned, but on the other hand, hopefully this is an opportunity for growth, even if in only a small way. If I fail, at least I will have tried. If I succeed, hopefully I will have had a great adventure, gotten to know Kerbin better, be a better engineer, conquered my own laziness and lack of constancy. 

At this point I'm planning on majority sea travel, with a couple of small trips across the land bridges. We may need to modify our plans as we go. Pre 1.1 sea travel was a much more impressive accomplishment. So I'm taking the easy option in a sense, but hey at least now it's achievable for the likes of me!
 

_______________________________________

CONTENTS

1. Design, Development and Testing

Day 1 (below)

Day 2
Day 2 - Part 2
Days 3 & 4

Route planning
Preparation checklist
Final Planning

 

2. The Expedition 

Day 1 - Birth and Death
Day 1 - Part II - Berthy and Depth
Days 2 & 3 - Kraken Attacks!
Days 4, 5 & 6 - Plain Sailing & Kraken Bites
Day 6 - Vehicle Replacement

Days 7 & 8 - Progress...?
Days 9 & 10 - Help Sails on its Way
Days 11 & 12 - Reunion
Day 13 - Unflipping Day
Day 14 - Sullen, Sadness; Glade and Gladness

Days 15 & 16 - Secret Seas, Kraken, Claws and Sounds
Days 17 & 18 - Gulf Crossing & Black Rock

3. Vessel Overviews

The Waarn

_______________________________________


DAY 1 

Prototypes and Explosions

_______________________________________

 

Design Thoughts:

Two different schools of thought on Elcano. A car that can swim or a boat that can walk. 

The great blue yonder beckons...

Several different experiments in the SPH resulted in a catamaran type hull. With more parts touching the water there is more drag I think, however I found with longer outriggers/pontoons the craft is more stable. 

The goal here for me was being able to run this craft stably at 4x speed with physics. 

So to that end I set off on a sea-worthiness trial and managed to cross the Eastern Sea by water, for the first time! 

Amphibious!

fLxLPvg.png

QCLivdp.png

Land!

xq4PfKo.png

Check it out Jeb!

_____

Bill: " Hey, Jeb, can I come out too?"
Jeb: "Ummm. No. Maybe you can get out next time." 
Bill: "Flip." 
Jeb: "You're just the engineer after all. You were drinking cokes in the back seat the whole way here, while I was doing all the hard work!"
Bill: "..."

_____

Name:
Always important. Embody the ethos of the mission; inspire the adventurers. Being stumped, I asked my wife, who took one look and said: "it looks like one of those spiders that walk on water"

1 minute of googling later,,,

Behold!: The Dolomedes Triton!
The namesake is an spider which is known to run on water - hence the reference to Poisidon's son - and even 'fish'. How apt - a sort of amphibious arachnid. Additionally it's coloring's are similar. 

Drag:
So, this craft is efficient enough. Having experimented with different nose cones I found the NCS + small nose cone is pretty efficient. 
-Further, interestingly the 'straighter' or more level the craft moves through the water, the less drag. Having long pontoons seems to level out the craft and enable higher speeds. Additionally the vertical stabiliser helps with a little snaking in the water which knocks off speed too. 
-Fully loaded this craft can cruise at around 25 m/s.  I realise this is no speed boat. But I think this speed is acceptable, and more realistic this way.
-Having small wheels housing clipped into the pontoons seems to make no difference to drag. Funny, I thought it would. This is good news, as it means more ground clearance underneath for those nasty hill crossings. 

Engines:
Also the Juno engines, whilst not as efficient as the Wheesley are better suited to this craft. When trying the Wheesley, the higher thrust meant the craft tipped more with the center of thrust higher than the center of mass. With the smaller engines this is not a problem. The center of mass needs to be low down so it doesn't tip, so the pontoons are the primary fuel tanks. 

On returning from the sea trials...

xnm67S0.png


Next thoughts:

Wheels:
Overland small landing gear + the Junos should get me there for the land bridges. But I'm not so sure about this. This is probably what I'm most worried about. Before I set off, I definitely need to test thrust going uphill. Might need the Wheesley after all...or moar Junos (*lol*).

Surveying:
To that end, aerial survey will be in order. I'll fly to the two proposed land sections which need to be crossed and check their inclines and plan out the ingress and egress points. 

Fuel: 
The on-board fuel load gets the craft pretty far. In one test I went 335km and used 1,079 LF, which was only a small fraction of the tanks capacity. Even so, as with most Elcano attempts, a refuel will be necessary. I'm thinking a cargo-plane drop of a refueling rover (read orange tank with wheels!). Or possible a VTOL plane could be fun. I've recently discovered these and they can be quite fun. Regarding the actual refuel connection...To Klaw or not to Klaw that is the question. (Last time I seriously used the Klaw 'round Minmus to recover a lost capsule the Kraken was awoken and ate my game. Ships in orbit started accelerating. Nasty. Nearly lost my whole carerr save game. Fortunately I'm a little OCD with backing up.)

Logging:
Don't really want to have to manually log lat./long. The old Persistent Trails mod is not up to date, so that's out. 

Up Next: ...Land Trials & Refueling tests!

 

Edited by Maverick_aus
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I tried the car that swims, but ultimately didn't like how it worked out. The rovers I had became too clunky. But that was way back before water was redone.

In either case, I like how slick your catamaran is looking. Nice job! :D 

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Looking good, Maverick. A few things to consider -

1) How are you going to refuel. Are you going to use refuelling tankers, ISRU, what? If you're using tankers, it might be a good idea to run with KAS/KIS to make refuelling easier. If you're running ISRU, you might want to rebuilt in 2.5m parts, as apparently the small ISRU parts are kinda rubbish.

2) Land bridges - You might want to stick a third pair of wheels in the middle of your pontoons. It'll be no fun if you go over a sharp incline and break your pontoons in half.

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Hey guys!
Thanks for checking out my page. Great to see some veterans of the challenge coming by! Hopefully in this adventure I can provide you with some of the entertainment you've provided the community already! 
 

9 hours ago, damerell said:

Sea is certainly the easier option, especially with something like MechJeb in play; lay in the course and go to bed.

G'day damerell!
Yes. I'm thinking of warming into this challenge with the sea route, then if I still have the stomach for it, go the land route. Looking at existing mission reports, discovering and taking in Kerbin's geographic beauty seems to be one the big pluses.
 

7 hours ago, Claw said:

I tried the car that swims, but ultimately didn't like how it worked out. The rovers I had became too clunky. But that was way back before water was redone.

In either case, I like how slick your catamaran is looking. Nice job! :D 

It's the Mighty Claw!
Thanks for taking the time to come on down here. Yes I've been reading about your cockroach escapades. Yes sea crossing attempt with the old physics - very impressive. Thanks for the feedback. There's a few gadgets and gizmos to add. I wanted it to look more 'explorer'-ish, like the Land Rovers packed with fuel cans and all sort of supplies, a shovel on the front etc. But I'm keen to keep parts to a minimum as well. 
'All hail the Claw!'

 

5 hours ago, Thalamask said:

Looking good, Maverick. A few things to consider -

1) How are you going to refuel. Are you going to use refuelling tankers, ISRU, what? If you're using tankers, it might be a good idea to run with KAS/KIS to make refuelling easier. If you're running ISRU, you might want to rebuilt in 2.5m parts, as apparently the small ISRU parts are kinda rubbish.

2) Land bridges - You might want to stick a third pair of wheels in the middle of your pontoons. It'll be no fun if you go over a sharp incline and break your pontoons in half.

Hi Thalamask! Thanks for your thoughts.
1. Yes I'm still thinking this through. No ISRU - trying to go light and 'realistic' as possible. KIS/KAS refuelling - yeah - tempting. I think I want to keep mods down for this. Plus, I've recently managed to connect my VTOL fighter with a land base using the docking ports. It's fiddly but I like the 'authenticity' of it. (Well, maybe I just like the extra challenge!) (Quote me on that when I'm swearing, stuck out in no man's land out of fuel because I can't dock!)
2. Absolutely good call. The four wheels (as above) are not final. Land testing starts today, so let's see where we end up...



 

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1 hour ago, Maverick_aus said:

Looking at existing mission reports, discovering and taking in Kerbin's geographic beauty seems to be one the big pluses.

Definitely this. There are a few worlds where the scenery is actually quite interesting to explore (and several where it's a bit less interesting). I highly recommend not just setting the course for MechJeb to pilot while you sleep. You might miss out on a unique outcome of this challenge, but the choice is yours.

 

Also, I hesitate to give specific advice unless asked (because discovering for yourself is half the fun :P). But I do want to offer: If you ever have a question, please feel free to ask. You'll probably get more advice than you expect!

For example, I have my own thoughts on the miniISRU (which you can no doubt read in my thread), but it may suit your desires.

Maybe the only unsolicited advice I will give is test, test, and then do a bit more testing. :)

 

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22 minutes ago, Claw said:

Definitely this. There are a few worlds where the scenery is actually quite interesting to explore (and several where it's a bit less interesting). I highly recommend not just setting the course for MechJeb to pilot while you sleep. You might miss out on a unique outcome of this challenge, but the choice is yours.

 

Also, I hesitate to give specific advice unless asked (because discovering for yourself is half the fun :P). But I do want to offer: If you ever have a question, please feel free to ask. You'll probably get more advice than you expect!

For example, I have my own thoughts on the miniISRU (which you can no doubt read in my thread), but it may suit your desires.

Maybe the only unsolicited advice I will give is test, test, and then do a bit more testing. :)

 

Thanks Claw.
And I really appreciate you offering help.
As you say, half the fun is discovery and design improvement. One thing I would like to ask you about: RE: path tracking/logging (esp. over water): in the OP for this challenge (realise you didn't post it) Fengist says you can track the vessel using ScanSat BTDT. Trying to figure this out. Do you know what Fengist meant by this / how to use the BTDT to show path? Not sure if you have experience with ScanSat or not. It updates ship location in real time with an icon which is fine, but other than taking a screen grab of the ScanSat map showing the vessel icon and then compiling them into map at the end, I can't figure a way to map path detail using this scanner. (Experimented, checked ScanSat site etc...).
Also, I'd rather do the challenge with as few mods as possible. Do you have any suggestions for path logging (automagically)? 

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I have not used ScanSat in a very, very long time. So unfortunately I'm not much help there. Sorry. :( 

20 minutes ago, Maverick_aus said:

Also, I'd rather do the challenge with as few mods as possible. Do you have any suggestions for path logging (automagically)?

I've run all my missions without mods, and just take pictures of the globe periodically. Though that can be time consuming to deal with, since I usually shrink them down and embed them in another pic. I think there are a couple mods out there that can track position over time, but I don't remember the names off hand. I'll have to take a look. I know at least one other recent-ish entry used a tracker system. @IvanSanchez used BTDT here. Perhaps he can give you some advice on getting that one to work, if you've already installed it.

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19 minutes ago, Claw said:

I have not used ScanSat in a very, very long time. So unfortunately I'm not much help there. Sorry. :( 

I've run all my missions without mods, and just take pictures of the globe periodically. Though that can be time consuming to deal with, since I usually shrink them down and embed them in another pic. I think there are a couple mods out there that can track position over time, but I don't remember the names off hand. I'll have to take a look. I know at least one other recent-ish entry used a tracker system. @IvanSanchez used BTDT here. Perhaps he can give you some advice on getting that one to work, if you've already installed it.

Thanks Claw. Beautiful -  I'll follow up with IvanSanchez. (by the way, how do you tag/reference him like that? Is there a BBcode tag or something or do you just type an 'at symbol' before his name?

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To page somebody, just type the @ and then their forum ID.  Pretty soon a box will pop up below with their name in it, and you click on that.  Presto, a blue-highlighted name that gives that person a notification that you mentioned him in a thread.

Anyway, I went around by boat myself. The only land crossing I did was the narrow next up far NE of KSC, between the eastern ocean and the great inland sea.  This is the least amount of land to cross, especially because there's a long lake in the middle oriented in the direction you want to go.  I used Firespitter pontoons (which still worked back then) with built-in wheels so had rather less ground clearance than you, and had my terrain detail set at high so there was the most topography.  Still, I managed to get across the somewhat rugged terrain up there without high-centering my boat.

My boat had the CoM pretty far aft to balance the line of trust being well above the pontoons.  This had the beneficial side effect of helping get over ridges.  At the crest, the center point of the pontoon would pass over before gravity pulled the front end down to the other side, so the bottom of the pontoon never scraped on the crest.  It did make the front end slam down hard sometimes but the boat could handle this because the wheels were designed for aircraft landings.  Also, I chose my path carefully to avoid the worst ridges.  Thus, your airplane landing gear should do fine, too.

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Hi Geschosskopf!
Great to finally meet you. I've seen your posts around the place. Thanks for your tips! 
Your mission looked like a great time. Your story was very entertaining. And I liked how you provided clear maps and labels. 
I've been considering electric power plant as well. I've built a solar plane before using the Near Future KAX electric propeller (here). But then I thought I'd limit myself to stock. Now after reading through your mission report, you're making me rethink again! I do love the idea of self-sufficiency - not needing to refuel. Plus the added narrative shaping factor of having to spend the night at a landed location. But then again, aerial refueling is attractive narrative-wise as well.
RE: CoM and CoT. Interesting. I'll have a play. Although I'v found with the new physics, it seems important to keep the vessel pointing straight as possible on water as the added drag with a higher angle of attack seems to slow the vessel. If I had the CoM further back it might create too much of a positive AoA. Where before it was a matter of just keeping the vessel from crashing into the water and RUDing now we can focus on getting the speed (and fuel efficiency) up.
RE: Path - yes I think I'll be taking similar route to yours having looked at the sea-route options. Was toying with going further north at that point to get close to the ice, just for the fun of it. However, the main deciders here will be a) the aerial survey of that area -i f it's too mountainous, I'll have to go the more southerly route through the inland sea. b) the ability of my boat-car to drive safely. Land trails are underway as we speak. I'll post an update. The small aircraft landing gear are pretty robust, as you said. Although I'm still getting this...

tPsZK9L.png


Although, to be fair, that was after a brief um...flying incident at the peak of the hill. Yup. Maybe a bit fast. Just a bit. 

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16 minutes ago, Maverick_aus said:

Great to finally meet you. I've seen your posts around the place. Thanks for your tips! 

Thanks for the props :)   But I'm far from the most knowledgeable and helpful person here.

 

16 minutes ago, Maverick_aus said:

I've been considering electric power plant as well. I've built a solar plane before using the Near Future electric propeller (here). But then I thought I'd limit myself to stock. Now after reading through your mission report, you're making me rethink again! I do love the idea of self-sufficiency - not needing to refuel. Plus the added narrative shaping factor of having to spend the night at a landed location. But then again, aerial refueling is attractive narrative-wise as well.

I think, given all the changes in the past year, that burning LFO in fuelcells is pretty much inescapable for electric motors (props or wheels), so you'd still need to refuel.

 

16 minutes ago, Maverick_aus said:

RE: CoM and CoT. Interesting. I'll have a play. Although I'v found with the new physics, it seems important to keep the vessel pointing straight as possible on water as the added drag with a higher angle of attack seems to slow the vessel. If I had the CoM further back it might create too much of a positive AoA. Where before it was a matter of just keeping the vessel from crashing into the water and RUDing now we can focus on getting the speed (and fuel efficiency) up.

With my circumnavigation boat, the CoM was as far back as it was so that she'd sit level on the water at full throttle.  The off-center thrust forced the nose down and that matched the heavier stern's tendency to sink.  In those days, the pontoons worked best when more or less level.  Otherwise, the boat would wander all over and ultimately spin out and crash.

But that was before the new water and buoyancy changes.  While I haven't tried a boat yet in 1.1.3, the water has been been unchanged the last few versions so I think it's pretty much the same still..  Of course, there are no more Firespitter pontoons to compare things to these days.  But anyway, with a boat made of normal rocket/airplane parts, speed increases as the wetted area of hull decreases.  This can be accomplished by pitching slightly up.  This causes the boat to get up on a plane with only the very stern still in the water, and you can reach insane speeds.  My best was 250m/s with the Holy Mackerel, getting Mach effects :).  The initial pitching up , and keeping the nose up, is facilitated by having the CoM very far aft and the thrust line as close to the hull as possible.

However, while getting really fast is relatively easy, slowing down again is quite hard.  As you slow down, all the parts at the bow have to come back into contact with the water and when they do, even though their vertical speed is quite low, their horizontal speed is way more than enough to kill them.  Thus, except for speed record attempts, you really don't want to get the bow out of the water.  Basically, parts that are intended to be in the water at any point in time should always stay in the water, and other parts should always stay out of the water.

 

16 minutes ago, Maverick_aus said:

RE: Path - yes I think I'll be taking similar route to yours having looked at the sea-route options. Was toying with going further north at that point to get close to the ice, just for the fun of it. However, the main deciders here will be a) the aerial survey of that area -i f it's too mountainous, I'll have to go the more southerly route through the inland sea. b) the ability of my boat-car to drive safely. Land trails are underway as we speak. I'll post an update. The small aircraft landing gear are pretty robust, as you said. Although I'm still getting this...

I don't recommend going over 30m/s on land in any rover, much less an amphibian.  But one of the big problems with rovers these days is that wheels wig out during physical time warp, which means you can't make the trip go any faster than real life.  That puts an extra layer of challenge into Elcano.  Good luck with it.

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DAY 2 

More Prototyping and More Explosions

_______________________________________

Being content the Dolomedes Triton passed yesterday's water testing, that is, that the craft floats: at an optimium level with any fuel load, stable, at moderate speed, at if need be 4x warp, etc., today it was crunch time. Sure the boat can act like a boat. Tick. But can this boat walk on land? Not run necessarily, but walk. 
The results were...well pleasant but surprising. Here's a glimpse of the end...

OqqaJgO.png

Land Trials

Specifically I wanted to know:
1. Would the small aircraft landing gear survive rough treatment on rough ground. And if so, how rough, what speeds etc. 
2. Are 2x Juno engines going to be enough to push this craft uphill? And if so, how steep? What would the max. gradient be? What about fuel load? I know from using these gear on aircraft they can take a beating, but there's a big different between a craft of this fuel capacity smacking into the green after a small jump off a hill empty versus weighed down with a useful 'exploration' load of fuel on board. To this end, would I need medium wheels? Part of design philosophy of this craft was to keep it light, sleek, and low-part count. So I didn't want to go on the exponential bloat spiral: "Well I need more fuel to go further...But that will be heavier. So I better put the larger engines on. Oh, but then I'll need the stronger struts..etc etc" So would the added weight of the medium wheel be worth it?
3. Can this thing stop, then start again uphill? 
4. What's the traction like? I haven't done much roving around since 1.1, and the high-speed power sliding I have managed around KSP in mostly aircraft, didn't fill me with confidence regarding grip.
5. Clearance. How many extra wheels will I need in the middle of those pontoons? 

[Now...by about here, I had hoped igmur would have all pics uploaded, so I could finish this post tonight, but it's mysteriously stalled. Ah and sleep beckons...]

I'll finish this report tomorrow. In the mean time, to give you some indication of how the testing went...

yAXODPD.gif
 

Stay Tuned for 'Day 2 - Part 2' Tomorrow.... 

_______________________________________

7 hours ago, DaMachinator said:

As for the logging, a fairly simple kOS script should work.

@DaMachinator Ah. Good plan. I've scripted a little - managed to get my Mk3 space plane reliably into orbit that way. Love kOS. I'll look into. 

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6 minutes ago, Maverick_aus said:

Ah. Great idea. I've scripted a little - managed to get my space plane reliably into orbit that way. Love kOS. I'll look into. 

In particular, this feature looks useful. Just don't break or otherwise lose the kOS drive, or have it

copy missionlog.txt to 0.

every so often. (0 is the archive drive.)

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1 minute ago, DaMachinator said:

In particular, this feature looks useful. Just don't break or otherwise lose the kOS drive, or have it


copy missionlog.txt to 0.

every so often. (0 is the archive drive.)

Thanks, mate! Although I think you might have fluffed your link there (links back to this mission report page).

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11 hours ago, DaMachinator said:

This bloke has done most of the work, I think. But with graphical output. 
https://www.reddit.com/r/KerbalSpaceProgram/comments/4d8qee/knowing_persistent_trails_probabaly_wont_make_it/
Just need to figure out how to use the command you referenced to output the long. and lat. data to a file, at points in time. 

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Day 2 - Part 2 

_______________________________________

Here's the map of testing:
0s2zaOM.png

Test 1 - Basic Incline Ascent

Location: What better place to test, than the conveniently located hills nearby. 

g1Eb3ZE.png
Off we go.

bSfMOHK.png
Ascent began well... 

ZL6tSnx.png
Ah. We might have a problem there. 

IlrEumW.png

g9ectpS.png
Even Jeb looks a bit afraid there!

MtdcP6M.png
Funny how all that's left after these crashes is the wheels.

GW7pHqa.png
*Bill egresses to initiate crash investigation procedures. 
Bill: Jeb, I think we may need to rethink the incline testing velocity. Jeb?

ENYZYxC.png
Jeb: Weee! Flames! Boom! Let's go again! 

eAuq1i0.png
Bill: Jeb!

*Jeb hops out to inspect the damage

i8i9hWz.png
Jeb: Hmmm. Bill, you're really a glass half-empty, kind of guy. You know that right? 

12kol6u.gif
Jeb: We can work with this...


So after a few more of these...

QOHARuj.png

and these

tPsZK9L.png

The testing got Serious, Rigorous & ScientificTM ...

Test 2 - Medium Wheels
The Dolomedes Triton ("Now with medium wheels!") passed all the required tests:
Incline ascent, Stop start, etc...
DIGlUGE.png

We quickly sanity-checked medium wheel water drag was not excessively high (point 2 on map). A brisk beach landing at speed (point 3) confirmed the craft's amphibious transition ability. No problems.

Spotting a flattish plain, Jeb decided to open the taps. Sprint was successful at upwards of (from memory 100 m/s) without spinning out or crashing.These medium gear are strong!

With the new-found geo-confidence, Jeb thought he may as well push the limits and ascend a small mountain!

NqHMp4Z.png

Success! (in the distance is KSC)
OqqaJgO.png


My son decided to name the mountain Mt Pass. Sensible boy.

On the way down, we tested stability, grip and handling on the steep decline.

eSG7fm5.png
6zxmZl7.png

Success!

Verdict thus far: 
The testing was to prove that, given the DT can swim ok, could it walk on land acceptably. That is a boat which pretends to be a car sometimes. But given the results above, at this point I'm wondering if it's actually a car dressed up to look like a boat which pretends to be a car sometimes. It only goes a moderate, sustainable 30 m/s on water, yet on land....
1. Jumps off hills at high m/s, landing hard and surviving. 
2. Stop halfway up a moderate incline, then accelerates upwards.  
3. Scales a small mountain.
4. Survives the decline from the mountain.

At the end of a hard day's testing and development, the boys look quietly confident as they contemplate the journey ahead in the Dolomedes Triton ("Now with medium wheels!")  
xWLMHt8.png

Up Next: Day 3 Testing - Power plant decisions:

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22 hours ago, Geschosskopf said:

Thanks for the props :)   But I'm far from the most knowledgeable and helpful person here.

 

I think, given all the changes in the past year, that burning LFO in fuelcells is pretty much inescapable for electric motors (props or wheels), so you'd still need to refuel.

 

With my circumnavigation boat, the CoM was as far back as it was so that she'd sit level on the water at full throttle.  The off-center thrust forced the nose down and that matched the heavier stern's tendency to sink.  In those days, the pontoons worked best when more or less level.  Otherwise, the boat would wander all over and ultimately spin out and crash.

But that was before the new water and buoyancy changes.  While I haven't tried a boat yet in 1.1.3, the water has been been unchanged the last few versions so I think it's pretty much the same still..  Of course, there are no more Firespitter pontoons to compare things to these days.  But anyway, with a boat made of normal rocket/airplane parts, speed increases as the wetted area of hull decreases.  This can be accomplished by pitching slightly up.  This causes the boat to get up on a plane with only the very stern still in the water, and you can reach insane speeds.  My best was 250m/s with the Holy Mackerel, getting Mach effects :).  The initial pitching up , and keeping the nose up, is facilitated by having the CoM very far aft and the thrust line as close to the hull as possible.

However, while getting really fast is relatively easy, slowing down again is quite hard.  As you slow down, all the parts at the bow have to come back into contact with the water and when they do, even though their vertical speed is quite low, their horizontal speed is way more than enough to kill them.  Thus, except for speed record attempts, you really don't want to get the bow out of the water.  Basically, parts that are intended to be in the water at any point in time should always stay in the water, and other parts should always stay out of the water.

 

I don't recommend going over 30m/s on land in any rover, much less an amphibian.  But one of the big problems with rovers these days is that wheels wig out during physical time warp, which means you can't make the trip go any faster than real life.  That puts an extra layer of challenge into Elcano.  Good luck with it.

Thanks for the thoughts G. That's really interesting about pitching up the vessel etc. I love your Mackerel. It's hilarious. 

Yep - I hear you re: rovers on land at phys warp. I haven't been able to pull it off once at anything like a proper speed. That's out. 1:1 timing the whole way over land it is.  

Quick qn on the formatting of your posts - how did you respond inline with multiple segments of my post quoted?

After all this talk of electric engines, I've decided to think a bit more about propulsion. I'm testing dual power plants at the moment. Firespitters electric prop + 2 Juno. It's working very well. I've always loved the idea of a solar powered explorer.

I just wanted to check though, with you - my design and plan is starting to get closer to your mission: I may take a similar route, similar power system (solar electric) etc, sea borne...I'm conscious of trying to do this my own way, but it's starting to overlap a little with yours...just thought I'd check with you before pursuing the electric route more...

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1 hour ago, Maverick_aus said:

Quick qn on the formatting of your posts - how did you respond inline with multiple segments of my post quoted?

There are 2 methods I've found.

1.  Quote the whole post.  Then go to where you want to insert a comment and hit ENT several times to create some blank lines in the quote.  Then move the cursor back up to the top of this series of blank lines and hit ENT again.  This usually breaks the quote into 2 parts at that point.

2.  In the original post, highlight the bit of text you want to quote and comment on.  A box pops up saying "Quote this".  Click on it, and that highlighted section of text appears in a quote box in the reply area.

I find the 1st method best if I want to discuss several points in the same post.  The 2nd method is useful for quoting 1 small bit out of a long post, or quoting several folks in the same reply.

 

1 hour ago, Maverick_aus said:

I just wanted to check though, with you - my design and plan is starting to get closer to your mission: I may take a similar route, similar power system (solar electric) etc, sea borne...I'm conscious of trying to do this my own way, but it's starting to overlap a little with yours...just thought I'd check with you before pursuing the electric route more...

There are only so many ways to do this.  If you go by boat, and you want to stay in the water as much as possible, there are less choices than if you go by land.  So knock yourself out.  I didn't patent anything :)

 

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Days 3 & 4 

Moar Solar

_______________________________________

Design Direction Change
Solar endurance has always fascinated me. The Solar Impulse aircraft recently piqued my interest. And so inspired by that I began work on a solar endurance plane. Val managed to fly it to the peninsula due east of KSC, proving the basic concept. (However I never developed it to a global (circumnav-by-air) scale.) 

Now I've got the perfect chance to apply that same philosophy to land and sea travel. Chatting with Geschosskopf recently, and seeing his Mission Log reminded me of firespitter's capability. I had intended to stick to stock for this challenge, but the more I thought about it, and the more I played with solar, the more attractive it became. I checked firespitter's compatabiltiy with 1.1+ and no worries there.

And so I got going with design modifications and new testing. The Dolomedes Triton's chassis has already been tested on land and sea, and is a stable platform. I just had to work on powerplant, power supply and thrust direction issues. 

So without further ado, I present to you:... 

Dolomedes Triton ("Now with electrickery!")

rrrr8ra.png

Ok so she's not the prettiest anymore, but boy can she hill-climb! Check out the following mini-story after the design notes

Design Notes
Content that DT  can cross sea at 31 m/s with a sizeable fuel load on two Juno's power alone, can speed across plains, and climbs small mountains (well, ok hills), and having spent serious time and effort proving these capabilities, I wanted to add electric propulsion without compromising any of those conclusions and having to retest. 
So first off, I added firespitter's basic electric propeller to the rear central hull. Conveniently this propeller is rated at 40kN, which is precisely the same thrust output as the two Junos. Additionally, it weighs a negligible amount - 0.17 t.
next, the propeller would need a power source. It has a healthy thirst for E, needing 24 per sec. So some solar panels....

This resulted in...

0lakgmL.png
(This is a shorter version of the pontoons I was trying)

and 

lfI7hOv.png

However...

A quick sanity-check of the handling of the craft at sea told a sad story: instability with bouncing, poor top speed. 

Suspecting that it was a CoT far above the CoM and not appropriately angled, experiments confirmed what Geschosskopf had been trying to tell me a few days go. Once the direction of thrust issue was addressed, it was much better. 

Thrust
For level sea-cruising the craft need is happy on 40kN to sit on 31 m/s (at 17.6 tonnes). But based on land trials, I wanted 80kN for steep incline ascents if needed. (That's why you can see auxilliary Juno engines in the pics above).  

Thus the design was settling down to a dual-propulsion concept: infinite electrical daytime sea-cruising possible at 40kN, and a limited liquid-fuel powered Juno boost if needed up-land. An additional benefit is in powerplant redundancy - in the event of electric failure (like breaking it off!), I could change plans and fill up on LF and continue with jet only. 

Power
However, in testing to determine how many solar panels I'd need, I noticed it was trivial to power the 24 e/s electric motor. I wondered how much of the sun those solar panels could catch. Ie could I get my boost from the sun's rays instead of the limited LF. What about 2x electric props? This could enable unlimited (electric) boosts, or alternatively a higher cruising speed the entire time! I could leave the Junos onboard with a little LF for an emergency super-boost or as backup powerplants. Yes: 120kN! That's results in a pretty sweet TWR for this little craft. Read on to see how sweet. (The only downside was turning my sleek beauty into a sola-panel-covered turtle.)

So the current stage of design looks like this:

LPZmRkE.png

cTmXjPh.png

7zEFldi.png

G5iwiOn.png
 

_________________


Hill Climb

A testing story...

Jeb: C'mon Bill, enough fiddling with those panels! Let's take it for a SPIN!

UKxIy5g.png

After a bit of messing about in the bay, the boys bump into this island. I don't know what you call it in your KSP universe, but it had never been given much attention before here.

otwlBan.png
LybFiVl.png

This led to a funny thought, and an unplanned experiment.
SOlUGup.png
Bill: Jeb...no. NO! There's no way we can get up there!
Jeb: Oh c'mon! Let's give it a try!


Funnily enough Bill was right. But the DT has enough thrust to plant both feet on land. 

  z8Gqa92.png

Jeb, Val and Merkin had flown around and over these uninhabited islands, and occasionally deposited drop-tanks on them, but had never thought to set foot (or tyre) on them. Until now. 
otwlBan.png

Seeing the sandy beach around the corner, Jeb pressed on. 

Getting a run up, he floored it, 120 kN of POWERRRRR!
VN85V4h.png

Ok...I wonder how far we can get up before we stop and slip down?...
nxBX81r.png
Slowing down now...Yep, maybe half way. That's pretty good!...wait....

K9fgkTQ.png

Uh...

33VtWqp.png

MEXKhO8.png
That's halfway!
Bill: JEEEEEEB!

prCIfuV.png

xQung2b.png
View from above

Decelerating the whole way, Jeb's wondering if they'll make it to the top. Bill's just wondering if they'll make it alive!

Suddenly...

YWNsqo9.png


...air! Were flying! Oh we've MADE IT!

6zdVWUA.png
Jeb: Yeeeeeeee-haaaaa!
Bill: AHHHHHHHH!

eHQZOFr.png

Safely at the top. The. top. of. the. mountain/island. wow. With the only damage being a couple of nose cones broken from a rough broaching of the hill. 

MuN4nLS.png

1y2qKID.png
Jeb: Look at that. You can see all the way home from here. 

9oksmch.png
Bill: Yeah. Look at that. You...broke...my...NOSE-CONES! 
 

GUzOYdU.png
Look at that. 

....

Having enjoyed the view (or stressed over the slightly broken craft, accordingly) the two testers set off down the slope, homeward.

kjzB6na.png
Hmm. Doesn't look too steep from here...

VsByeZ1.png
But ahead...

h3596aD.png
Wait...

1V2ly3F.png
Over the edge...

CzIlkyr.png
Jeb's view (look at the angle of the prograde marker on the artificial horizon!)
 

RD3G8ML.png
Utilising the reverse thrust on the dual 40kN elec props, plus brakes, Jeb could control the descent. Just don't roll!

MXrmmfh.png
Safe splashdown! Jeb entered the water happily under 10 m/s. 

1WfAnNV.png 
Map of the proceedings. 

What a rover. I think this craft is nearly ready for the Elcano challenge!

 

Edited by Maverick_aus
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I think this may have been mentioned elsethread, but to track with the BTDT, just turn it on and have the Scansat small map visible in screenshots. http://www.chiark.greenend.org.uk/~damerell/games/ksp/minmus-5-flats.png is a screenshot of a Minmus trip with BTDT tracking.

On 29/06/2016 at 2:28 AM, Claw said:

Definitely this. There are a few worlds where the scenery is actually quite interesting to explore (and several where it's a bit less interesting). I highly recommend not just setting the course for MechJeb to pilot while you sleep. You might miss out on a unique outcome of this challenge, but the choice is yours.

I only suggest it for sea legs - there is some quite interesting scenery but the bits where the entire horizon is flat and blue aren't it.

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