Need help tweaking my Duna lander/rover unit

[ajburges]

I was inspired by another thread to make a rover that can be squeezed into a service bay. Since the only configuration that makes sense for is landing (more taking-off) from a body with atmosphere, I decided to make the rover for Duna (focused on completing survey contracts). My first test run on Duna itself ran into a huge issue.

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It seems that parts clip/sink further on Duna than they do on the KSC runway. On Kerbin, the rover could drive into the bay without issue, but on Duna the ship sinks enough that the ceiling is too low and the docking ports slam into each other.

Anyone know of a way to make my service bay height over ground more predictable with stock parts? It needs to be low enough the tires can roll over the lip, but high enough to not clip through the floor of the bay.

On a related note: any tips to improve the rovers handling without expendable resources? The chassis cannot grow any more.

[InterCity]

Repair plan could go like this:

1) Put another structural panel below the service bay

2) Hyperedit/fly to duna, try the sinking depth.

3) Repeat steps 1-2 until reaching desired height

4) ???

4) Profit!

Or you can try putting landing legs onto the service bay in such a manner that they end at the height you want. I'm not sure that's gonna work, though. The panel solution is your best bet.

[cephalo]

I find that the lander foot depth issue is entirely unpredictable. Sometimes they sink, sometimes they do not. Sometimes only one foot sinks. Combine that with the height that wheels rest on their suspension is also different on each celestial body, and you just can't rely on any kind of precision.

EDIT: nm what I said earlier, I didn't understand the problem. Anyway, this issue is that you can't judge wheel suspension height in the VAB/SPH. They appear there as if they are pushed up all the way as if in high gravity. Once you get out into some other gravity, the wheel height will change drastically. So a Kerbin solution won't work on Duna, which won't work on Minmus. All very different wheel heights.

Edited July 12, 2015 by cephalo

[Foxster]

How about ramps made from panels at each door to the service bay...

Even if the panels sink into the surface a bit you might still be able to drive up them.

Or maybe even cooler would be to dual-purpose your airbrakes to a deployable ramp...

Needs more work and I gotta get me to bed now. I'm sure you'll figure something out though.

Edited July 12, 2015 by Foxster

[ajburges]

I want to avoid radial slabs because the whole point of the design was to optimise lander drag. A dubius goal for Duna, but it amused me. A panel ramp did work more reliably on Kerbin before I moved away from it. Maybe I could do some shenanigans with the offset tools to occlude it from drag with the service bay.

The airbrake idea sounds interesting though.

I think I will abandon the concept until next update. I herd today that rover wheels are going to be reworked next update. Given the tolerances of the storage space, almost any change to the wheels will require significant rework.

Depending on how my career Minmus mission goes, my Duna lander of choice may just be a mining rocket plane. It shouldn't need a rover, and even if it does, Mk3 cargo bays allow for the use of bigger wheels if I include jump jets.