Mun Rover and Mun Gravity

[Sorcie]

I'm having an issue with Mun roving. I tested probably 50 designs on Kerbin for anti-roll, etc. The best resolution is controlling which wheels are powered, steering etc.

My problem is of course the gravity being so low that the rover wants to slide to the side or just lose it's heading often. I have figured out using ASAS and locking my heading helps, but I have to toggle it on and off every time I change either horizontal or vertical heading, hills etc. It seems that using physical time warp helps, since I assume it's spacing out inputs over time so they are less twitchy. It still seems to have some other effect and gravity works better, which makes no sense.

Does anybody have other tips for Mun roving and helping the vehicle stay planted better and not slide, flip, or other catastrophic and kerbin eliminating events?

I had already placed a 3T rover and it was similar but worse. I redesigned and did all that testing and it still only helps so much. This vehicle is 7T, stock, no clipping or anything strange. This is the same issue I had with other Mun rovers I have tried but figured I'd ask for some help!

Thanks!

[UNSC]

Switching to docking mode keeps the rover controls online but does not affect orientation.

[Specialist290]

With that specific design, I'd imagine that some of the issues are caused by having a relatively high center of mass.

Depending on how you've mapped your keys, command pod torque could also be coming into play -- the default WASD commands for driving rovers happen to overlap those for rotating your craft, and if the total mass is light enough in comparsion to that of the command pod(s), it can get quite tricky to control. Switching to Docking Mode controls or remapping your rover controls to the translation keys (IJKL) might help here.

[Sorcie]

Yeah it has a probe body on it for non command pod control and I forgot to control it from there, that might help some for sure. The center of gravity was of course a concern, but it handles great, when not practically floating away, which really seems to be my issue. Perhaps I need an even heavier rover with a super low center of gravity hehe.

Thanks for the help, I'll try the docking mode as well.

[MickG]

I used the new wheels on my modular Munbase and it kept flipping over even going just 2m/s. I put the other wheels on it and it was much better. My guess is the new wheels don't do well with low gravity. They worked just fine when I tested the design on Kerbin. I suggest you try the other wheels.

[Chrono]

I'm guessing that rover (in the pic) is return capable? Otherwise I'd wonder what the fuel tanks are for. My first rover was pretty fun, hit 90 m/s before it hit the edge of the crater and when rocketing off into a barrel roll.

A few tips I'd give you is control your center of gravity, keep it low to the ground, you can drop your center of gravity by adding I-beams to the lower parts of your rover. Second, my most successful rover so far, Wade 02, is very wide, the more area your rover covers the less chance of a flip. Compare an H1, a vehicle that needs explosives to flip it over, to an H3 something I've seen do a barrel roll when rear-ended by a midsized sedan.

Try recreating just the rover portion of your craft and use KSP's tools to see where your center of gravity is.

[Atanar]

Widening your weelbase and track helps always. Most people seem to try to make their rovers as compact as possible which doesn't provide any advantage at all (unless if you really have to case it in somewhere).

[Chrono]

Oh I can see the reason for a compact rover, its very lightweight. In fact the rover in the Pic is fairly brilliant. My visual assessment, from the thrusters fuel cells and parachute I'm guessing it's return flight capable, using the rover base as a launch platform. This is great, but also lends to the problem your having, the vehicle is award and is slow.

Sad reality, weight efficient rovers are slow and delicate, typically created from tissue paper and plastic straws.

[georgTF]

As others have mentioned. You cannot overestimate the benefit of wide track, wide base and low CoG. Even then the most dangerous situation is one where you bounce off the ground at an angle. That will lead to landing on one wheel at high speed and you can kiss it good bye then.

You can still steer the rover as if it were a plane/heli, this way you can sometimes recover and land on all wheels. If you feel adventurous you could add 4 orange radial engines (and balance them) so if you get badly airborne, burn for altitude, level the rover, kill horizontal velocity and descend. Like i said, adventurous. But great for skipping around Minmus.

Most of my rovers were crap, only two are used regularly and one is a heavy tanker. Here's the other one. It does well enough.

Yea, it looks like junk i know, i'm not competent enough to build them both pretty and usefull. I also like to drive over the launchpad and runway at speed just to see what kind of impact it can take. Better to know ahead of time.

Good luck.

[Aeshi]

The 0.20 wheels have a pretty bad habit of spinning out of control when you try to do just about anything, try using the Rovemax 1 wheels instead. They're a bit heavier and a bit more power-hungry, but are MUCH more stable.