Custom Stock Bearing: Any advice?

[cubinator]

I'm currently trying to make a fully stock bearing (1.0.5) for...a certain evil plan I have, which cannot yet be unveiled...I found a really nice design here, but I have no idea how @JZ6 got the fairing to load whilst open. I would make a custom design based on theirs, but I can't replicate the open fairing without some serious glitching. I don't want to use someone else's bearing directly, because I want my [CENSORED] to be entirely of my own design. Any tips on making a smooth bearing that can carry a moderately heavy load? It needs to be able to withstand the mass of over 20 2x2 structural panels* in microgravity, plus several Clamp-O-Tron Juniors.

*unless it can be made extremely compact, like within .6 m wide. Then it would only need to withstand that many 1x1 structural panels.

Thanks in advance for helping me! BTW what I am attempting will most certainly be the first of its kind in KSP. 

Edited June 5, 2016 by cubinator

[bewing]

Um, how fast does it need to spin? There are two ways of making fairings -- one is a hollow "interstage fairing" that has something on top of it, and the other is a solid closed "top fairing".

@sgt_flyer knows a lot about how to make interstage fairings.

I doubt that design would work in 1.1.2 with those severely clipped wheels, though.

Edited June 5, 2016 by bewing

[cubinator]

7 minutes ago, bewing said:

Um, how fast does it need to spin? There are two ways of making fairings -- one is a hollow "procedural fairing" that has something on top of it, and the other is a solid closed "top fairing".

I doubt that design would work in 1.1.2 with those severely clipped wheels, though.

1. It doesn't need to spin very fast, it just needs to spin smoothly with a bunch of stuff attached via docking ports.

2. That's why I'm doing it in 1.0.5.

[sgt_flyer]

for making open ended fairings :

place your fairing base, don't make a shape. place a part (or several, to make clearance) on the payload side of the fairing, including a part large enough to close the fairing around it with the needed opening.

shape the fairing to your liking, close it around the last part.

remove that last part, the fairing disappears. from there, use the Undo command (ctrl+z), the part reappears, but not the fairing. then use the Redo command, the part disappears, and the fairing's shape you made reappears, open ended

note, if you pick up directly the fairing base (and not the part before it) and replace it after having built the fairing shape, you will have to use again the undo / redo command to restore the fairing's shape. for copying a fairing shape, you need to save the original as a subassembly, and use the subassembly each time you want  a new copy (symmetry don't work on keeping fairing shapes either)

works exactly the same in 1.05 or 1.1

note, 1.1 open ended (or interstage) fairings are made of a lot of colliders - these can negatively affect the game (and it's colliders multiplied by the number of placed segments in addition to the rest !) besides, 1.1 1.25m fairings are not really round inside - they have 8 colliders per vertical slice in x2 mode (so, octogonal), 9 colliders in x3, 8 in x4, and x12 in x6 (so that would be the most round).

@JZ6  bearing in 1.1 would end up being made of 7 vertical slices, in x6 for most interior roundness, so you end up with 42 individual colliders for this bearing alone - creating a dry bearing instead would drastically reduce the number of colliders

 

afterwards, for smooth low rotation speeds in microgravity, dry bearings can work very well (and can be made really compact ! - ex, a 0.625m part with x6 solar panels around it). just be sure there's no straining on the bearing during docking events .

 

create some test rigs if you want to check the smoothness of parts - place an I-beam or another flat parts, and mount the part you want to test on a decoupler (with additional probe cores, reaction wheels and RTG's attached to the part) above that flat part - then decouple it, switch to it, and observe how it 'rolls' to determine it's shape.

in any case (wheeled or dry bearing),to ensure smooth operation, it's important to have the center of mass of the rotated part in the middle of a single bearing (or in the middle of two bearings if you use two)

 

Edited June 5, 2016 by sgt_flyer

[cubinator]

@sgt_flyer Thanks for the advice!

10 hours ago, sgt_flyer said:

note, 1.1 open ended (or interstage) fairings are made of a lot of colliders - these can negatively affect the game (and it's colliders multiplied by the number of placed segments in addition to the rest !) besides, 1.1 1.25m fairings are not really round inside - they have 8 colliders per vertical slice in x2 mode (so, octogonal), 9 colliders in x3, 8 in x4, and x12 in x6 (so that would be the most round).

@JZ6  bearing in 1.1 would end up being made of 7 vertical slices, in x6 for most interior roundness, so you end up with 42 individual colliders for this bearing alone - creating a dry bearing instead would drastically reduce the number of colliders

I'm doing it in 1.0.5, so that shouldn't be a problem.

10 hours ago, sgt_flyer said:

afterwards, for smooth low rotation speeds in microgravity, dry bearings can work very well (and can be made really compact ! - ex, a 0.625m part with x6 solar panels around it). just be sure there's no straining on the bearing during docking events .

Ok, so I should be able to make a "compact" version, that would probably be better because it would have shorter joints and smaller parts. There would be a lot of docking and undocking within short distances, would that be a problem?

Also, it would be easier (control-wise) if the bearing could be turned via the central part instead of the rotating one. Is that possible?

[sgt_flyer]

4 hours ago, cubinator said:

@sgt_flyer Thanks for the advice!

I'm doing it in 1.0.5, so that shouldn't be a problem.

Ok, so I should be able to make a "compact" version, that would probably be better because it would have shorter joints and smaller parts. There would be a lot of docking and undocking within short distances, would that be a problem?

Also, it would be easier (control-wise) if the bearing could be turned via the central part instead of the rotating one. Is that possible?

for lots of undocking, as long as there's no major force trying to push the bearing out of his roll cage during docking events, you should be fine.

for controlling it's turn from the center part, if it's meant to turn in only 1 direction, mmh - maybe you can make two sets of landing legs (or landing gearts) - alternating between the two sets of legs/gears to push the other part (ex : legs set 1 deploy and push against a panel) - then retracts, not yet in range of it's second panel). set 2 deploy and push against it's own panel, then retracts) - legs set 1 has now a new panel accessible for pushing then retracting) . jet / rocket engines exhaust pushing against the other part could work too.

 

 

[cubinator]

33 minutes ago, sgt_flyer said:

for controlling it's turn from the center part, if it's meant to turn in only 1 direction, mmh - maybe you can make two sets of landing legs (or landing gearts) - alternating between the two sets of legs/gears to push the other part (ex : legs set 1 deploy and push against a panel) - then retracts, not yet in range of it's second panel). set 2 deploy and push against it's own panel, then retracts) - legs set 1 has now a new panel accessible for pushing then retracting) . jet / rocket engines exhaust pushing against the other part could work too.

 

 

No, it should be able to rotate in both directions. Here's my current design that I concocted earlier today:

It seems to work fine when I only use the rotation keys, and the connection will be reinforced with several docking ports anyway. (I hope multi-docking doesn't cause too much glitchiness...)

Also, it looks like I'm going to have to use 2x2 panels based on the size of this bearing. That's ok, it will leave more room for the docking ports (which will be required for structural stability).

Edited June 5, 2016 by cubinator

[sgt_flyer]

@cubinatorfrom here, now that you built your own bearing, you'll see it's a lot of the following to make it work smoothly :  slights adjustment in vab -> test -> back to VAB for new adjustment and so on

a slight thing to help stabilise your bearing's tilt with 1 or 2 parts - you can attach an OX-stat to the cage, and position it with the translation tool so it ends up between the two small reaction wheels of the rolling part (of course, there has to be nothing else there ^^) the result is that if the gap between the two RWs is finetuned just to the ox-stat's thickness, if the bearing tries to tilt it'll be stopped by the solar panel.

keep in mind though (especially in 1.05) - the physical colliders don't exactly match the visible 3d model. (the colliders are generally slightly smaller) - so don't be afraid to experiment