Rovers

[ebphoto]

I've made a few rovers to take surface samples, carry Kerbals etc.. How do you get them launched and on a planet? Small ones seem to be okay but large ones are definitely a challenge. Can anyone help me with this?

Thank you,

E

[FancyMouse]

Launch: If you can't reduce drag, pack some more fuel and prepare a slower ascent.

Land: Depend on your rover design. Could get a skycrane, or make your rover self-landable.

Without specific rover examples I think that's the only general advice I have now.

[Alshain]

Like FancyMouse said, if your rover is too big to fit in a fairing, just launch more vertical. Don't do the gravity turn till you hit 30km. You will need more fuel but the yanking effects of drag will be minimized. You can build it in-situ with docking ports (or KAS).

There aren't a whole lot of solutions for rovers because KSP Rovers have so little use. Real rovers have computer automation, something KSP is without and even mods haven't figured ground vehicle automation out yet. There are occasionally contracts you can do with a rover, but those contracts can more easily be done with an EVA jetpack. At best you, if you land just right, you can drive it between two biomes. With the right mods you can use rovers for construction purposes. But overall rovers in the stock game are kind of boring so not a lot of people build them I think.

[Hagen von Tronje]

At best you, if you land just right, you can drive it between two biomes. With the right mods you can use rovers for construction purposes. But overall rovers in the stock game are kind of boring so not a lot of people build them I think.

If you pick a good landing site on Minmus, a rover could reach four biomes within minutes (named flats, plain flats, slopes, midlands. Lowlands might be possible too in some places.). Slopes are not so great to land on, either, so just in general a rover is a decent way to get a full science set in that case. Also nice because the location of such sites is very easy to discern at a glance.

But you're not wrong that mods open up a lot more options, even if they aren't specifically rover mods, and as much as I like rovers, without any mods at all I have to really work to find practical applications.

[FancyMouse]

On the other hand, I feel hoppers with rover wheels are extremely powerful to go around places on bodies like Mun. Solves both problems of slow speed of rovers, and precise landing of normal hoppers. With a proper base set up for refueling, I can go wherever place on the body however many times I want.

[Sharpy]

One more (expensive) method for launching any arbitrarily unwieldy payloads (which still allow attaching something on top) is what I call "pinecone nose". Pick a largish nose cone (may be a fuel tank type), 8x symmetry, Vernor engine, and place 4-6 times. A nose cone covered with 48 vernors can stabilize pretty much any payload. And if it can't, add moar vernors.

[Belphegor]

i haven't made rovers yet after 1.0, but i simply used to construct them with a centered COM and put them right on top of the rocket, inverted with the wheels facing upwards. to land them in non atmospherical conditions either attach some fuel tanks and engines using radial detachers and eject those after landing, or if it's very big use a skycrane and docking ports (craft with 4 or more engines placed far apart so the rover can be docked in between them) to bring it from orbit to the surface. downside of the skycrane is that it's a lot of added weight and it's usually better to send it seperatly on a second rocket

there are probably better (more efficient) ways to do it but i hope this gives you some idea of how to handle it

to stay on the ground in low gravity you can use ion engines with the nozzle facing upwards

19.5t rover with skycrane in the background (far right)

Edited August 18, 2015 by Belphegor

[cantab]

To launch awkward payloads in general I suggest putting them between two or more rocket stacks. That means that you won't have drag up front trying to flip your rocket, though you might be draggy overall so pack extra delta-V. If there's a mass imbalance consider individually tweaking engine thrust limiters.

I land large rovers on their wheels. You can either have the chutes and/or engines integral to the rover, or on a decouplable skycrane, pods, or similar. Small rovers can be stuck on the side of a multi-engine lander, again using thrust limiters to maintain balance, or can be carried in a service or cargo bay.

There are occasionally contracts you can do with a rover, but those contracts can more easily be done with an EVA jetpack.

Contracts to run experiments at multiple close-together points on the ground can appear. If the experiment is something like a seismic survey you're not going to do that with an EVA Kerbal. (Well, unless you're using KIS, but it should never be any surprise that mods mess with game balance).

[LN400]

If you don't mind mods, then Infernal Robotics offers some real neat solutions to bringing "oversized" cargo into space and to other worlds, all fitting inside fairings. I've made a crane that is now on Mun and several rovers, none of them needing more than 3.75m fairings. The fun challenge is to come up with a design where you can make it as compact as possible to fit inside the fairings.

Mun crane, without and with fairings, and unpacked on the Mun surface:

Unpacked it's more than 12 meters long.

One of the bigger rovers:

[ebphoto]

Wow, that's some awesome looking stuff. I've messed around a little with the robotics mod. I'll have to give that a shot. It never crossed my mind but now that you mentioned it, I can see how some of the powered hinges might help to fold thing like wheels etc., up. Once it's on the rocket, how did you bring it to the surface??

E

If you don't mind mods, then Infernal Robotics offers some real neat solutions to bringing "oversized" cargo into space and to other worlds, all fitting inside fairings. I've made a crane that is now on Mun and several rovers, none of them needing more than 3.75m fairings. The fun challenge is to come up with a design where you can make it as compact as possible to fit inside the fairings.

Mun crane, without and with fairings, and unpacked on the Mun surface:

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot770_zpszt8ezadu.png

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot773_zpsyhmguhir.png

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot778_zpsqows8lmy.pngUnpacked it's more than 12 meters long.

One of the bigger rovers:

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot776_zpsjjxrsqgz.png

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot775_zpsf2lxp9cm.png

http://i189.photobucket.com/albums/z193/WhoCaresWho/screenshot780_zpsvbnqgeqa.png

[LN400]

For landing, if you look closely there are small tanks underneath the crane and buggy with tiny engines, just enough to land safely. The crane has long enough "legs" that can be rotated down enough to function as landing legs, pop off the tanks and engine (using a docking port since I don't want a decoupler to shoot the thing skywards in the low gravity environment) then simply drive clear of the debris before straightening the legs for normal driving.

The rover works very similarily except it doesn't have any landing legs at all but with the reaction wheel I am able to pitch over so the front wheels make contact, then drive/wiggle my way clear of the debris.

[bigcalm]

Launching unwieldy payloads generally means going more vertical to avoid unpleasant drag effects.

I personally use MechJeb's "Surf Up" for the first 10k or more which keeps things stable (though I don't trust MechJeb to launch anything reliably from Kerbin).

Here's my Tylo Rover (will not return to orbit!)...