How do I build rovers that won't tip over?

[thereaverofdarkness]

Seems like no matter how low I put the center of mass, I always run into the problem of hitting invisible bumps in a flat surface causing my 15 m/s rover to launch itself upwards at Minmus escape velocity, twirling wildly. It will then slide and bounce uphill, picking up speed the more parts it knocks off the thing. How do I make a stable rover that can be driven at any reasonable speed without spinning out of control?

Edited August 30, 2013 by thereaverofdarkness

[NGTOne]

There is no surefire way to do this - it's more about experimentation than anything else. KSP's grip model isn't really finished yet, and doesn't work particularly well. What I've seen work is attaching a few ion engines and xenon tanks (and lots of solar panels), and using them to provide extra grip by applying thrust downwards (the engines are pointed towards space). Now, this doesn't work too well for bigger vehicles, but liquid engines can do the same thing (just a lot less efficiently).

If that doesn't help, you can always try the track mod. Can't guarantee it'll work better, but the tracked vehicles I've built tended to have pretty good ground-holding abilities (though that may be because they were insanely heavy, but that's another story).

[allmhuran]

+1 for the ion engine solution, I have a 4-man rover and even a single ion engine providing some downforce certainly helps, as does a nice wide wheelbase. For most of my rovers I also have an action group to toggle the steering on the rear wheels for high speed turning.

I also build "roll cages" into most of my rovers using 1x1 structural panels so that if they do top over nothing is likely to break (structural panels have an impact tolerance of 80 m/s). It also means they roll back onto their wheels more often than not. For the larger ones I provide a mechanism to get them back upright using one LVN-77 on each side pointing upwards (so, downwards when inverted) and a very small amount of rocket fuel, a quick blip of the throttle and it's right way up again. For smaller rovers I tend to use one or two of the small (not smallest) landing legs to flip it back over. I don't have pictures here at work but I'll post some up later.

[NoMrBond]

Another way you can do it is now is use something with ASAS (possibly with a RW, like a probe core + IRW), the torque can actually be enough to stop the rover tilting (and thus flipping) although you can end up needing to either turn using torque instead of the wheels, or togging ASAS to turn

[Flixxbeatz]

-Widen the base.

-Don't make it high (a.k.a "moving tower") if possible.

-Keep the center of mass low.

[zxczxczbfg]

Wide, low bases and a low center of gravity help a lot. Also, try adding some SAS--I mean, inline stabilizers, to give you more torque and allow you to roll your rover back to its feet.

[thereaverofdarkness]

Thanks for all of the solutions guys! I especially like the idea of strapping an ion engine to it. I'd make roll cages but I'm trying to keep the part counts down so I can add them to a Mün base instead of having them as a standalone vehicle. I do try to keep the base wide and the center of mass low, but it seems like everything that belongs on the bottom is just made of lighter pieces. I have the same problem but to a much greater extent with the mark 3 fuselage. Its center of mass is absolutely bonkers and makes building planes with it very difficult.

[Xzabath]

I use RCS on my rovers turn the sas on and low and wide.