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Ideal landing speed for Minmus? (bouncing)


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So, to my shame, I've lost a couple landers and rovers on Minmus. (Minmus? It's really easy to land on Minmus!) It's my own fault, really - they come down @<12m/s, bounce, and SAS (set retrograde) flips them over. Then they're tall (Rockomax-64s), and have a high center of gravity, so the noses smack into the ground, or they roll down a mountainside, and SAS/manuevering can't keep up.

Now, obviously it's better to land in the flat plains, and I can (and have now) designed landers to be wider and lower. (Radial X200-32s instead.) I'm also turning of SAS along with the engines when I'm within a couple seconds of touchdown, so there's no unexpected rotation.

What i"m curious about is how to avoid the bouncing in the first place. Is there a maximum speed that is "no-bounce" for different planets? I would assume it varies with gravity, but does it vary with the ship or the number of legs? Or is there another recommended method?

TIA

On a semi-related note, is there a way to tell what the strength of connections and components will be? (It seems like some fuel tanks are more likely to fall off on impact, etc.) I'm sure there's some mod that makes it obvious, but I'm vanilla at this point.

Edited by dvp
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My landers bounce a lot too, specially in low grav Minmus. One thing that helps (I keep forgetting, tho :D) is to go from retrograde hold to stability assist before touchdown. You'll still bounce, but you'll keep pointing the right way. The quickest way, in my opinion, is to tap 'F', since it'll toggle off all SAS, then turn it on in Stability mode (default)

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1 hour ago, dvp said:

What i"m curious about is how to avoid the bouncing in the first place.

A few things.

One is, tinker with the settings on the legs.  In the VAB, you can adjust two settings:  the spring strength and the damper strength.  If you just slide the damper strength so that it's significantly higher than the spring strength, you won't bounce as much, because it absorbs energy on impact.  For a really low-gravity world like Minmus, you can probably make do with a pretty low spring strength, because there's not much weight to hold up after it settles down.

Also, Minmus gravity is so low that I find it's easy to just use reaction wheels to right myself if I do end up tipping over.  If you have a really tall / skinny / top-heavy craft, either add some reaction wheels or redesign so that it's squatter (wider-spaced legs on the ground, CoM not so high).

And finally... if you do tip over, a lot of the time you can recover with help from the engine, particularly if it's a gimbaled one.  Let's say you've fallen and you can't get up.  You're lying on a slope of some sort.  Even if you can't actually stand your vehicle up, you can probably use reaction wheels to muscle it around so that its nose is pointing straight uphill.  Do that, then hit the throttle while holding down the "pitch up" button.  You'll loft off the ground pretty quick, and the engine gimbal will rotate you pretty fast even if you have weak reaction wheels.  Once you get a few meters of clearance, then you can go through the landing process again and hopefully have some better luck this time.  :)

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make sure you're actually switched to surface speed. some of the areas on minmus are high enough that the game won't automatically switch from orbit to surface.

if you zero your horizontal speed relative to orbit, you still move relative to the surface, so the lander will always flip over / crash.

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5 hours ago, bewing said:

Always set your SAS to Radial Out just before you land (if you've got it as an option -- otherwise, Stability Hold).

 

 I use Stability Hold regardless. Works very well for fairly balenced crafts.  

A particular case no one mentioned yet: fairings (but not the bases) are insanely resistant.   You can just let you rover inside while it happily bounces. (If you don't mind people judging how you play {it don't matter, anyway})

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