How long would it take to circumnavigate Kerbin with an Amphibious Rover?

[Commissioner Tadpole]

Some of you may remember that one brave user decided to circumnavigate Kerbin entirely by land with a rover. But what if the trip was made with a rover suited both for grippy mountain climbing and water sailing?

Amphibious rovers are very rare, but they still can be produced(mostly with mod assistance), as you can see from this image showing Tw1's amphibious Evepod:

The Kerbin land circumnavigation took around six weeks(or months, cannot remember), because the expedition had to actively avoid water unless strictly necessary. With an amphibious rover, the seas wouldn't pose a threat anymore and you could very well just drive in a straight line, avoiding only the occasional montain or pit, thus cutting a lot of the original time. But what would be the resulting length?

[Boomerang]

Depends entirely on how fast you can go. I've see a handful of particular sturdy boats that can do 80m/s+ in the water. If you're just starting out building boats, you'd be lucky to maintain 10m/s without something being destroyed by the wacky water physics. But let's say you manage to build something that can do 50m/s in the water and you pick a great circle route that's entirely water. The circumference of Kerbin is pi*2(600000m) = ~3769911m.

If you're doing 50m/s entirely on water, not taking into account whether your craft is sturdy enough for time warp, that's:

3769911/50 = 75398s or about 20.9 hours.

Obviously that's just for that particular case. You aren't always going to be on water, you might be able to time warp and it depends entirely on how fast your craft can go by land and sea both.

Edit: Also, going by wheels on land gives you the benefit of using electricity from either RTGs or solar panels to power wheels. You'd need some sort of consumable fuel (most likely just LF for jet engines) to propel yourself. Which adds an entirely different dimension to the problem.

Edited November 2, 2014 by Boomerang

[turkwinif]

Welp, with simple maths, the circumference of Kerbin is about 3,769,911.2 meters along the equator. Assuming an average velocity of 10 m/sec, 0 elevation (Kerbin being a perfect sphere), and no change in direction, it would take approximately take 376,991.12 seconds, or 104 hours, 43 minutes, and 11.12 seconds. Of course, it'd take a lot longer than that in-game.

Edited November 2, 2014 by turkwinif

[SkyHook]

I am sure someone will correct me if I am wrong, but the surface of Kerbin is impossible to circumnavigate ENTIRELY by water. The surface actually connects. But for a more mathematical answer, refer to the post above mine.

[RocketPilot573]

I am sure someone will correct me if I am wrong, but the surface of Kerbin is impossible to circumnavigate ENTIRELY by water. The surface actually connects. But for a more mathematical answer, refer to the post above mine.

Just looked a a map, and indeed you cant. Might want to add wheels to the boat.

[cantab]

Most boats can handle a little land by running on aircraft gear, which they often have to get into the water in the first place. I suspect the fastest speed would be attained by a jetboat that only crosses land where it's essential. 100 m/s or more isn't uncommon on a speedboat, while a wheel-driven rover can't go much above 25 and a jet-powered rover is a deathtrap.

[astropapi1]

Just looked a a map, and indeed you cant. Might want to add wheels to the boat.

So I took a look at the map from "Kerbalmaps.com" and noticed that, with careful planning, there's only a small piece of land that you will need to go over when circumnavigating Kerbin. I've never been there personally (might do it tomorrow), but I think it's like a canyon with lots of small lakes. With a wide wheel base and good driving, it should be possible to take a boat through there.

[Tripzter]

You going to try to be Kolumbus now?

[L3GO]

If wookiee went around in a rover i think i shall attempt this in a boat. My mission will start next week.

[Frank_G]

To endeavors! Godspeed sirs!

I am really looking forward to take a peek in the mission logs

[Commissioner Tadpole]

Also, going by wheels on land gives you the benefit of using electricity from either RTGs or solar panels to power wheels. You'd need some sort of consumable fuel (most likely just LF for jet engines) to propel yourself. Which adds an entirely different dimension to the problem.

Hm, I think the fuel problem can be avoided by setting up refueling stations across Kerbin. But of course, the problem will be when crossing huge gaps of water. Either the trip will have to be shortened, or we'll have to work on some water-bound refueling stations. I guess we'll have to use The Klaw for this one.

Welp, with simple maths, the circumference of Kerbin is about 3,769,911.2 meters along the equator. Assuming an average velocity of 10 m/sec, 0 elevation (Kerbin being a perfect sphere), and no change in direction, it would take approximately take 376,991.12 seconds, or 104 hours, 43 minutes, and 11.12 seconds. Of course, it'd take a lot longer than that in-game.

Ouch. Well, better hope the ship has residence quarters for the crew members to rest on.

I am sure someone will correct me if I am wrong, but the surface of Kerbin is impossible to circumnavigate ENTIRELY by water. The surface actually connects. But for a more mathematical answer, refer to the post above mine.

Well, I did say amphibious - in other words, a rover that can traverse both land and water with ease.

[Hodo]

I remember way back before .21 I made an amphib rover for the Dakkar Rally challenge and drove from KSC to the old KSC or KSC inland as it is known.

It took me 6 hours, with stock wheels and a single jet engine for pushing the amphib across the water at 10m/s. I may do it again one day with a new rover design... it was one of the most fun challenges I have ever done.

[Commissioner Tadpole]

Alright, everyone, I made a plan!

Before starting the adventure, four refueling stations would be deployed into Kerbin's surface, so the amphibirover won't run out of fuel. And to economize fuel output, the path won't be able to be a straight line like I had suggested earlier on, and will make some deviations, but will overall be on the equator.

Here is a map representing the voyage:

Blue lines represent land travel, Yellow lines represent water travel, Red circles represent refueling stations.

[JtPB]

If wookiee went around in a rover i think i shall attempt this in a boat. My mission will start next week.

as said above, you cant do this. you need an amphibious rovboat. or you can just try this with airplane & refueling stations around the globe.

[cantab]

Rover wheels are very draggy, so in order to go fast at sea you need to get them out of the water. The only approach I can think of in stock is to have something that on land carries the floats (probably intakes) on the roof, and then rolls itself over in the water.

[Commissioner Tadpole]

Rover wheels are very draggy, so in order to go fast at sea you need to get them out of the water. The only approach I can think of in stock is to have something that on land carries the floats (probably intakes) on the roof, and then rolls itself over in the water.

Wouldn't it be better to stick the rover wheels on LT-2 Landing Legs?

[cantab]

That doesn't seem possible, other parts can't be attached to the legs.

Docking port or claw solutions might be possible though, but probably tricky to make the conversion.

[r_rolo1]

You can use the tiny engines as hinges + landing legs as hydraulics and macgyver out a solution that pushes wheels out as will

[L3GO]

Would using Ion engines during the day to save fuel and yes it may make the trip longer but you could lower the amount of refuelling stations being used.

[cantab]

Thanks to the bugged Isp calculations, jets are actually even more efficient than ion engines.

[Geschosskopf]

The Kerbin land circumnavigation took around six weeks(or months, cannot remember), because the expedition had to actively avoid water unless strictly necessary. With an amphibious rover, the seas wouldn't pose a threat anymore and you could very well just drive in a straight line, avoiding only the occasional montain or pit, thus cutting a lot of the original time. But what would be the resulting length?

Well, stock boats don't turn very well. If you use Firespitter floats, you can do about 110m/s (the floats explode at 120) on the water and have rudders that work while they're moving. The Firespitter floats also have powered, steerable wheels that are VERY grippy and allow about 30-35m/s on land, and both modes work quite well at 4x physical warp. So, all you need for an amphibious rover is a pair of these floats, a jet engine to move on the water, and sufficient fuel.

I suppose you could meassure of the water and land distances around the equator and use the above speeds to figure out how long it would take, then divide by 4 for the warp, and that would be the play time.

But I can give you some emperical data as well. I built such a machine like a year ago and headed east. It took me about 30 minutes of real time to cross the 1st ocean, then I spent another 20 minutes or so driving on the next landmass. Then I noticed I was getting EXTREMELY bored with this project, especially since I hadn't gotten very far on land, and bailed on it. However, I figure that if you were really determined to torture yourself, you could knock the whole trip out in 1 or 2 real days, allowing for sleep, eye strain, and fingers cramping .

[DrMonte]

1. Using Firespitter allows to use electrical motors instead of jets. Those allowing to build some kind of "swamp boat". No refueling and lightweight. Just get some sleep at night.

2. MechJeb had some rover mod?

3. It's Magellan not Columbus.

[Tw1]

Oh hey! It's my machine!

Lately, I've been working on another amphibious vehicle- Laythe Aquatic Exporation pod. Developed from experience with Evepod but intended as a runabout, rather than mobile base. smaller, faster, but lacks the stability, science and living space Evepod offers.

"Promotional" Laythepod pictures:

It travels at a little over 20m/s on land or water, and can handle up to 1 in 5 slopes with the collision/tire repair wheels retracted.

Now on its way to the Jool system.

Good luck Commissioner!

I think you should name your rover something frog themed.

Edited November 3, 2014 by Tw1

[Geschosskopf]

1. Using Firespitter allows to use electrical motors instead of jets. Those allowing to build some kind of "swamp boat". No refueling and lightweight. Just get some sleep at night.

Yeah, but then you're limited to about 80m/s on the water, which makes the trip take even longer .