topic Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern in Inventor Forum

Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 26 Nov 2015 05:39:17 GMT

Okay, so this problem has been driving me nuts all day. I'm attempting to model a dandelion puff, which is, basically, just one seed replicated about a hundred times in a spherical pattern. Now obviously I don't want to model one hundred seeds, so a simple solution would be to create one, and then pattern it in such a way that I create a sort of sphere. Kind of like this:

Except with dandelion seeds, so I guess it would look like, yanno, a dandelion puff...

I mean, that's the basic idea at least. So how do I pattern an object in a spherical pattern. So far I've achieved this:

Which really isn't much at all, as I have no idea where to go from here as far as even making these lines into simple cylanders, much less actual models of dandelion seeds (plus the process to get here was horrible and not quick to replicate anyway)

Please help! 😞

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Thu, 26 Nov 2015 07:32:23 GMT

Welcome to the forums!

I'm assuming you're using IV2016, see attached file.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Thu, 26 Nov 2015 08:47:43 GMT

Ok, liked the idea too much so put a little extra effort into this one...

Same basic concept, just a lot of circular patterned solids.

(i made it so they're all seperate solids so you can turn some off for effect, 147 seeds in this one)

Too large to attach, download from my A360:

http://a360.co/1NQkHEd

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 26 Nov 2015 14:36:33 GMT

Awesome! Yes I am. Do you think you could explain how you did that? Thank you!

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Thu, 26 Nov 2015 15:14:46 GMT

Easy enough:
I modeled everything around the origin, starting with the sphere.
Then i modeled the seed shape and revolved that as a new solid.
I added a few thing for detail on the seed shape, but you can make it as detailed as you want.
Just make sure it stays part of that solid.

After finishing the seed, you start patterning it.
Use the circular pattern and select the "solid" option.
Select the seed as your solid and an axis in the part's origin.
Give the number of occurrences, make sure they don't overlap, set to create a new solid and hit OK.
Then it's just a matter of repeating the pattern step along the other axis (axii ??).

There is some variation in the occurrence number as you move up along the sphere, but you can see that in my file.
(i actually rushed my example a bit, for it to be "proper" i should have suppressed some seeds that overlap others)

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 26 Nov 2015 15:29:32 GMT

Oh wow, now I feel stupid. Thats a really nice and simple solution, thank you! It isn't optomal, as the seeds wont really be evenly distributed, but its a great start! Is there a different way that I could get the same affect but with designated points? I can generate an array of evenly dostributed points around a sphere in matlab and import them as points into inventor, but I dont know where to go from there as far as making cylinders from the origin to each point.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Thu, 26 Nov 2015 15:48:56 GMT

I'm inclined to say "yes", but i'm not entirely sure how to do it myself.
You can import points, but i'm not sure if you can use those in or as a pattern...

Then again, you're modeling an organic shape and those rarely are flawless or entirely symmetrical or evenly spaced...
You could just eyeball it... 🙂

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Mon, 30 Nov 2015 03:09:41 GMT

Thank you niels! Here is a render of a result using that method:

Pretty nice I'd say. However, I really am going to need to do this project with equally spaced seeds. I did this with the points I had via the process below

1. Imported points into inventor and drew a line from each point to the origin, one at a time.

2. I used the "create plan normal to axis through point" tool to create a single plane at the end of each line

3. I then created a simple sketch of a circle on one plane, copied it, and then pasted it to each plane by hand

4. I then made all the planes invisible

5. and then extruded each sketch, once again... one at a time : / By now this is getting old.

So yeah, pretty good, but now i have to somehow copy the dandelion seed onto each stem... and I have no idea how.

This process is painful and long. Does anyone know how I can simplify it? Perhaps a way to extrude all the sketches at once? Or to at least paste the sketch to all the planes in one swift motion? Or even better, to homehow pattern the stems along the points so I can bypass all these steps?

At the very least does anyone know how I could quickly paste the dandelion seeds to the stems quickly? This model was made with just 60 points, but the one I did via the other method had about 200. This method would involve hours and hours of repetitive work to accomplish that. Please don't make me do that!

Okay, thanks for all the help 🙂

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Mon, 30 Nov 2015 07:34:27 GMT

That's really a lot of repetitive work... :S
Could you share your point data file?
I'm not sure i can find a better solution, the only thing i've come up with so far to make the copy/paste a bit easier would be to make an ifeature of the seed...
That would still be a lot of inserting and positioning though...

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Tue, 01 Dec 2015 04:57:39 GMT

Sure! Here is the file which should contain all the point coordinates as well as the inventor file with all of the points already in it.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Tue, 01 Dec 2015 04:59:37 GMT

Sorry! I atatched a picture instead of the inventor file. Here you go

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Fri, 04 Dec 2015 02:08:09 GMT

Okay, so I went through it one time, same process I complained about before, and I decided to post the results. Well, I need to do it again cause I didn't do enough seeds (only 90), but here you go:

Still hoping someone has a better solution though....

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

malcolm_smith — Fri, 04 Dec 2015 04:22:41 GMT

Would it be better to do this as an assembly? Make a part file for the stem and seed and another part file with workaxes for the stem location. Then constrain instances of the stem to the centre of the sphere and each work axis. You can use the simplify commands if you want to turn it back into a single part file.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Wed, 23 Dec 2015 17:53:39 GMT

So I know this post is a little old but I wanted to reply. Work gets a little slow this time of year and I had a moment to think about another way to approach this model and I think I came up with something (if I may pat my own back) remarkable.

This uses only 1 pattern to create the "sphere" of seeds. I also made it such that the total number of occurences and the behaviour of the path can be editing through the parameters menu.

It's still not perfect so there are parametrical inputs that will cause the pattern to fail and there are some areas that appear less "full" but it will make sense for them to seem less full once you see how the model works. I'm working on both of these things but couldn't wait to share 🙂

Enjoy.

PS, I left off the splits in the "fan" at the end of the seed in the interest of saving memory usage and being able to manipulate/troubleshoot the model easily. These can be done before the pattern and easily made part of it if it were required. Also, the model is a little larger than your average dandelion. That's mainly cause I was just seeing if what I wanted to try could work when I initially started and wasn't concerning myself with accurate dimensions.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Wed, 23 Dec 2015 20:33:07 GMT

Update.

Alright, so I think this is about as far as I'm going to take it. Few minor changes to my previous version and where I went in to detail in some areas, I left out details in others. You'll see what I mean.

There are 200 individual seeds all created from 1 pattern and 1 orignal seed.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

-niels- — Wed, 23 Dec 2015 22:24:19 GMT

Hmm, this topic kinda slipped my mind but you've come up with a really nice solution Will.
I'll pat your back as well; nice creative thinking with patterns along a path!

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 24 Dec 2015 01:51:01 GMT

Brilliant Wimann! I am both grateful and impressed. However, would you mind explaining a bit more how this works? I can create the helix shape pretty easily but when I try to pattern a seed along it the seeds all stick out at the same angle unlike with yours. How do I fix this? I assume this has to do with sketch defining them...?

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Curtis_W — Thu, 24 Dec 2015 17:14:35 GMT

Hi ryanavolpi,

I think what you're wanting is to click the more button >> at the bottom of the dialog and choose Direction1.

You can see JDMather do this at about 8:15 of this video:

https://knowledge.autodesk.com/community/screencast/866aca3b-5401-4317-89a1-2d0d398f3937

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 24 Dec 2015 17:18:50 GMT

I'll make a video when I can get back into the office. It'd be nice to have the video for future demonstration anyway.

Keep checking back in 🙂

Thanks for all the positive replies guys. Much appreciate it.

Re: Modeling Dandelion / Evenly Distributing Objects in Spherical Pattern

Anonymous — Thu, 31 Dec 2015 03:06:12 GMT

Sorry for the length of the video 😕 I explain pretty thoroughly at each step