Edit: Changing Frame to Top yielded analogous results to Front version.

With respect, I think that the BottleFeedArray script is not complete, or not correct.
It seems to me that the bottle is sitting on its bottom, sunk into the cylinder.

The bottles should sit vertically, alongside and partially intersecting the screw/cylinder.
The center of the side of the bottle should, more or less, align horizontally with the axis of the cylinder.
The bottles are to be rotated around their vertical axis, as they move to the right.
The cylinder is the blank stock which will become the screw.
In an actual physical model, the screw rotates, but due to relative motion, the CAD script rotates the bottle around the cylinder,
and the bottles become the cutting object, as the bottles are booleen difference subtracted away from the cylinder, multiple times.

I think that the script needs to have added a rotation of the bottles about the cylinder, "centered" on the helix axis.

(I deleted my previous comments on 2d sweep, which was my faulty thinking.)

- Brian

Hi Brian, that sounds logical. Thanks for figuring it out!

Previously Barry wrote this:

"The bottle is always vertical to the horizontal
screws and only rotates in the plan view."

I was focused in on that "only rotates in the plan view" part and so only did one rotation.

So Barry, can you please clarify that so I can make sure - at each station you need the object rotated in 2 ways, once in the plan view which is rotating around the world z axis, correct? Then another rotation around the cylinder/helix axis direction which is the world x axis?

It might simplify things a little bit if the cylinder/helix axis was right on a world axis starting at the origin, will that restriction work for you?

- Michael

Here is an Initial model in Top View, for use with TOP frame.

Utilizing Michaels script BottleFeedArray (Top frame version), places the arrayed bottles along the helix where they need to be,
but the script needs to have added:
Each successive bottle needs to be rotated so that its center axis is perpendicular to the cylinders normal at that Pt.

I am pretty slow at getting anything done. :-)

Each angle could probably be calculated, or ...

(The initial bottle's center axis may not be tangent to the cylinder, but is perpendicular to the normal.)

- Brian

The angle to rotate a cutting bottle around a regular helix , for bottle at station n, is probably something like:

(#helix turns * 360) * n / (#stations-1)

assuming the initial bottle is at station index zero.

But since the helix may be of variable pitches, the angle would be some other unknown formula,
so perhaps a "normal to normal alignment" of the bottles vs the cylinder, would be better?

- Brian

The axis of the bottle, versus the surface of the cylinder is worrysome?

Burrman, thanks for link and info.

Hi michael,
So take a cutting object (a barrel) and do a circular array with vertical step.

Now each barrel needs to be rotated around "it's"original axis, 90 degrees from the first barrel at zero, to the last barrel at 90 (a rotation which spans the vertical distance. The barrel is essentially flopped over onto its side by the end of the array.

Now this needs to happen on a variable pitch, as opposed to a linear pitch of the circular array vertical step.

The "randomize" command allows for the "rotation of individual axis" but its a random application. I dont know if the "morph" rotation can be done with code though...

Hi Burr thanks yeah array circular using a vertical step makes sense to me now. I'll see if I can adjust the script.

@Brian, I was thinking a bit whether the script should take the parameters for a helix and use helix calculations in it but like you mention it would be easier for things like variable spacing for it to take an already made helix curve like it currently does. I should be able to use a rotate with reference points to do the other kind of rotation, I'll try that in a moment here.

- Michael

Ok, hopefully the attached one has the proper rotations now.

It assumes the bottle is pointing upwards in the world z axis direction and is positioned around the start point of the helix, and that the helix/cylinder axis has its origin at the world origin and that the helix/cylinder axis direction is the world x axis direction as in Brian's InialFeedScrewTOP01.3dm file from above.

I think it should work ok if you substitute a variable pitch helix in but I did not test that. But it distributes the items by equal distance as traveled along the curve, so with a variable pitch helix trying to use an item count that's related to the number of helix turns won't place items only at the quadrant points of the helix as it would with a regular fixed pitch helix. I don't know if a sparse placement only at quadrant points is desired but it looked like some of the images had that.

- Michael

Well, the script seems to be working... (My superficial opinion anyway)

FALSE: I had to make the bottle hollow, otherwise got a helical ribbon with many bite marks on the edges.
(Using a solid bottle, the solid screw was formed by the booleans, but color of cuts matched the bottles, not the screw.)
Hollow bottle as cutter also worked...

Boolean difference is very slow. Several minutes for 50 bottles. 100 bottles taking "forever."

There is a lot of leftover surfaces after Boolean, but by selecting the screw, and hiding the "leftovers" the screw appears as a solid.

The Boolean difference needs to be done in smaller batches. 100 bottle screw, 180 degree rotation completed.

- Brian

The engineering goes into setting up the variable pitch helix...

The bottle can be assumed to have its verticle axis intersecting the beginning of the helix.
If the bottle's axis is beyond the surface of the cylinder, a new, larger radius cylinder should be made. (?)
After the larger radius cylinder becomes a screw, it can have its radius shaved down later. (?)

- Brian

About BottleFeedArray2
Does this result normal ? (50 steps - 12°)

Michael,
many thanks works just as needed.
Barry

Hi Pilou,

> Does this result normal ? (50 steps - 12°)

It is if you don't have your helix positioned as required, it looks like your helix is going in the world z axis direction instead of the world x axis direction.

- Michael

Hi Barry, you're welcome I'm glad that does the trick! And thanks to Brian and Burr for helping clarifying what was needed.

- Michael

<< you don't have your helix positioned as required

Indeed! :)

@ Michael
Ok the random colors are fixed! ;)
And the little trick Menu Styles / Tool Styles / Add new Default Styles (by 7) + Random Colors
and repeat is perfect for make speedy big random colors' palettes!

http://moi3d.com/forum/index.php?webtag=MOI&msg=2987.2
http://moi3d.com/forum/index.php?webtag=MOI&msg=3876.1

Well done Pilou!

I would like to see a Boolean applied sequentially for each bottle, which would be much faster, I think. (?)
There could be an option checkbox for this? Maybe I'll try after work...

An elliptical bottle has much faster Boolean dif, than the rounded rectangle bottle.

Maybe the MoI Boolean dif command could have a sequential checkbox?

- Brian

For oval bottle, Lofting the cut edges seems promising?

Finding the midpoint dip line of the cut edges, and lofting might work for smoothing?
The Iso's do not follow the ridges of the cuts.

- Brian

Bemfarmer,
Boolean issue?

What I would do is create a "profile" of my bottle (then run rebuild if it was segmented, like a rounded corner rectangle) then run the bottle array on the profile and choose a ridiculous amount of stations. Then loft those and do the Boolean diff with the new, single solid.

I have 1 question for Michael though.

Is there a way to set "an attachment point" to the bottle? If I have an elongated rectangle for a bottle for instance, and I want to set a "depth" of the bottles placement on the helix start point, the bottle "moves away" from the depth and helix as it rotates to the narrow side of the bottle/rectangle. So if I make a variable helix with a start radius of 5 and an end of 3, My resulting bottle at the minor radius' endpoint has moved out and away from the helix path.

Not sure if/how this could be done.

Hi Michael,
I have tried to run the script on a reverse twist helix and it does not seem to work.
The get around was to produce one scroll with a positive bottle rotation 90 degrees
and to produce another scroll ( same helix ) with a negative bottle rotation minus
90 degrees and then mirror the result.
The subtraction from shaft required careful attention as Moi struggled when all bottles
or groups of bottles where selected so as Brian as suggested it would be good if they
could be subtracted one by one as they are produced I think this the way the Autodesk
Feed Screw Generator plugin works.
An way Michael again many thanks for your help much appreciated.

Barry

Hi,
Very interesting topic, it awakened my curiosity.
I reproduce the simulation of this screw conveyors in Algoryx Momentum.
https://www.youtube.com/watch?v=9OBpMFdMZ3g
I have one question, after the using this script, the result of the boolean operation generates many facets.
it's possible or not to generate directly one smooth profile for boolean operation?
I have TopSolid but not this function, it's seem generate one surface smooth with the profile cutting.
https://www.youtube.com/watch?v=U93EzIzA_Hk
Best Regards.
Nicolas.