Small rovers, and not capsizing them...

[Skorpychan]

I recently got a small rover to the mun. It ran out of power after it flipped and destroyed the solar panels.

Having redesigned the thing to avoid loss of power (hopefully), I want to avoid turning it over entirely. Any ideas on driving/design for it?

Edited July 11, 2013 by Skorpychan

[Vanamonde]

What's it look like? Low and wide is more stable, and a couple of RTGs will avoid the problem of charging solar panels entirely.

[Johnno]

Mainly, don't drive too fast. Switch to docking controls and use torque to steer rather than turning your wheels. Lower your center of mass. You can also add landing legs on top to flip it the right way around, but with a small rover it's better to just drive slowly and carefully.

I tend to be ok going below 10 m/s, which actually is 36km/h. The Apollo rovers were capable of around 10 km/h.

[Skorpychan]

What's it look like? Low and wide is more stable, and a couple of RTGs will avoid the problem of charging solar panels entirely.

It's a rovemate body, with six small wheels on it (three each side), a battery on the back, panels on the top, a command seat on the front, and a small flat probe body in the middle.

I've added some of the smaller flat panels to the top surface, and an RTG to the front. Not much else I can do.

[Sid]

I haven't been playing KSP for very long, but I have spent much of that time flipping rovers on their backs

Here are my thoughts ( for what they are worth ) :-

The small wheels seem very overpowered even for 1g - you can help things a little by arranging a really low centre of gravity - I've found you don't actually need much ground clearance.

Use a self righting mechanism, CP Airbags are great for this.

Or you could use the rover body which comes with the AIES Aerospace mod ? - it's very stable and a really neat piece of design.

[Vanamonde]

If you're interested, here are some examples of low-and-wide, RTG powered, flip-resistant (but not -proof) landers. http://forum.kerbalspaceprogram.com/showthread.php/35916-Small-Medium-and-Large-moon-rovers-from-Yeahletstrythatdyne They come with delivery vehicles good for Mun/Minmus.

[Skorpychan]

Okay, landing mishap. The lander is upside-down. The rover, which I jettisoned as soon as things went tits-up on landing, is nosed forwards on the RTG. It's not upside-down, but it's well on the way.

It MOVES, but not very fast. And mostly in circles on the side of a hill.

You know what? The rocket worked. Screw the rover, someone can tip that back over later. Let's try another shot.

DAMMIT. Flipped that one too, it exploded.

Edited July 10, 2013 by Skorpychan

[capi3101]

Self-correcting system - I use two 24-77s and a Toroidal fuel tank slung to the underside of the rover. Put the 24-77s on the same side of the rover and aim them upwards. You flip over, just light them up and goose the throttle to right yourself. GENTLY.

You really only need one 24-77, but it looks cooler with two...like a massive set of exhaust pipes...

I stick mine to the front of my rovers. Since that's where you've got your RTG mounted, I might suggest you use a different side if you go this route. Wouldn't do if the damn thing were to accidentally snap off while you were trying the upright your rover.

Actually, scratch that. The way it works and with your design as you've described it, you'd want the rover to flip over butt first...

[tipsyMJT]

Attach some struts from the wheels to the Rover. It makes them flex less. I'm assuming that when the wheels bend during a turn, the wheels will pull the rover a small amount trying to return to original shape and flip. The struts make it more rigid and flex less.

[Skorpychan]

My last effort overturned at speed and exploded. I think it's a stability problem, rather than a self-righting problem.

I'm thinking a wider wheelbase, maybe with pocket-size girders on the sides of the rover to facilitate that. Possibly more wheels as well if they fit.

[Benie]

I've made a speed rover with an aerospike engine in the back. It can go as fast as I want it to, but I can't go 60m/s without the front wheels popping.

I was thinking of using a Xenon engine, but I like the thrust sound. It makes it sound more like a rocket car.

It's really fun to drive on Duna, feeling the rover lifting off the surface and watching the rocks whizzing by. Don't think I want to try it on the Mun, since it could stay up a lot longer and flip upside down, then crash and explode into a million pieces.

Bad thing about driving on Duna, frequently I have the thing veering back and forth after it hits a small pebble (be it a slight incline in the path of my rover) and causes it to flip end over end. Not fun.

I love Quicksave. Just wish I didn't have to make frequent "quicksave pit stops".

Edited July 10, 2013 by Benie

[capi3101]

My last effort overturned at speed and exploded. I think it's a stability problem, rather than a self-righting problem.

I'm thinking a wider wheelbase, maybe with pocket-size girders on the sides of the rover to facilitate that. Possibly more wheels as well if they fit.

That would probably help; basically anything that will lower your center of mass will do the trick. So would "driving over a smooth surface", but good luck finding something like that on the Mun. Minmus, now...

Problem with Minmus is that you MUST use the docking controls to steer a rover there...even a tiny probe core has enough capsule torque to flip over a small rover on Minmus. I know that one from experience.

[RocketPilot573]

Adding an SAS (The standard one) to the rover can help a lot. As the SAS will try to keep the rover from turning randomly and flipping over.

[Skorpychan]

This is a very small rover, and SAS modules won't fit. The probe core should supply enough torque, though.

Building a bit heavier worked fine. Lower CoM, slower acceleration. Landed on the wrong side of the mun, though, so I'm slowboating around to get to the kerbals I want to transport around.

Also, I had my first successful night landing! The ground snuck up on me like last time, but I was going a mere 10m/s, and so bounced a bit instead of exploding.

[Keome]

I made a small rover built on the 1x1 meter square plate. It worked fine on Kerbin. On the Mun, I found that the Kerbalnauts ate too many snacks and the rover would nose over if I braked too hard or if I jumped up and down on the front of it. There wasn't much room to add anything else, but I managed to squeeze a small radial mounted monopropellant tank onto the back. I guess the rover will serve as a tiny fuel truck, too, but at least it won't tip over when a slightly overweight Kerbalnaut sit sin the driver's seat.

[foamyesque]

This is a very small rover, and SAS modules won't fit. The probe core should supply enough torque, though.

Building a bit heavier worked fine. Lower CoM, slower acceleration. Landed on the wrong side of the mun, though, so I'm slowboating around to get to the kerbals I want to transport around.

Also, I had my first successful night landing! The ground snuck up on me like last time, but I was going a mere 10m/s, and so bounced a bit instead of exploding.

I've found that the SAS module actually makes a decent rover body in its own right. It's a bit large for what you're working on, but it works great with the RoveMax bubble wheels.

[MBobrik]

Small stable rovers ? simple. avoid useless stuff like RoveMate or RoveMax 1 2 wheels and build your rover with TR-2L around a single SAS like this

.

or nuclear

.

.

You will actually save weight because SAS weights a lot less than RoveMate and improves stability to the point where you can safely intentionally drive on two wheels over long distance if you want.

.

Edited July 11, 2013 by MBobrik

[capi3101]

...and if the electrical storage is an issue for you, slap a battery pack on there. Even the little one will give you more storage than the RoveMate, and even with the Z-500 you're still lighter.

Damn, I need to try this out...

[Teirusu]

One trick I've learned to help prevent a rover from flipping over so easily? Not sure if its been mentioned in the thread..

Disable steering in the rear wheels. This -particularly- helps with small rovers because they have such a tight turning radius, and very little mass. Thus, when you try to turn, your CoM is too light to prevent the flip-over. By disabling steering in the rear wheels, it makes the turning radius much bigger.

[MBobrik]

Behold, my newest, craziest, smallest ( only 4 parts), and surprisingly stable creation ( you have to operate rover fwd/back and rot controls separately to keep it under control, but it is surprisingly easy to learn and to do, and the rover can turn itself back straight from any position), so, if you want to make a really really small rover, you can use this and you never have to worry about capsizing :

.

Edited July 11, 2013 by MBobrik

[RocketPilot573]

Small stable rovers ? simple. avoid useless stuff like RoveMate or RoveMax 1 2 wheels and build your rover with TR-2L around a single SAS like this

.

or nuclear

.

.

You will actually save weight because SAS weights a lot less than RoveMate and improves stability to the point where you can safely intentionally drive on two wheels over long distance if you want.

.

Unfortunately, those wheels are bugged. If you drive them up and down a slope, then the rover will most likely crash within five minutes.

[Skorpychan]

Small stable rovers ? simple. avoid useless stuff like RoveMate or RoveMax 1 2 wheels and build your rover with TR-2L around a single SAS like this

http://i.imgur.com/1vsWRmX.jpg

.

or nuclear

.

http://i.imgur.com/5oOcEAF.jpg

.

You will actually save weight because SAS weights a lot less than RoveMate and improves stability to the point where you can safely intentionally drive on two wheels over long distance if you want.

.

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

Does that give enough room for some solar panels, a couple of command seats, lights, and a battery pack, though?

[capi3101]

Maybe not...but I bet you could put a structural panel or two on top of it to mount that stuff to it.

I don't really know of course; I haven't tried it out my own self just yet.

You go with the PB-NUKs and you might get away with not needing the solar panels. As for the battery pack, you might try the undercarriage. Lights, you might be able to put on the cubic struts. Just leaves the chairs...

[Skorpychan]

Maybe not...but I bet you could put a structural panel or two on top of it to mount that stuff to it.

I don't really know of course; I haven't tried it out my own self just yet.

You go with the PB-NUKs and you might get away with not needing the solar panels. As for the battery pack, you might try the undercarriage. Lights, you might be able to put on the cubic struts. Just leaves the chairs...

I'd honestly rather not irradiate the crew, tbh.

And the chairs are the important bit, really. Gotta transport kerbs somehow!

[brickviking]

And don't forget their snacks! What is it with kerbals and snacks, anyhow?

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