MARCH2006 Model Challenge

"TOP" wrote in news:1142292871.308307.92380 @e56g2000cwe.googlegroups.com:

Only two lofts... You gave me an idea. It'll be in the mail shortly...

HA! I finally beat Dale at one of Paul's games (he toasted me on the dodecahedron a year or two ago)

Not counting sketches, I have a revolve, a cut extrude, and two circular patterns. No equations, and (though it is a pain in the ass) I used a dim for the revolve reference so I didn't need to add any axes.

I have three sketches, though if I were pressed I could do it with two.

-Ed

Oh yeah - of course... I had to put in an offset surface for Paul's requirement of a surface, though that is for judging reference and doesn't really count towards the four features it takes to model the shape.

Shouldn't have posted so fast, I just saw that Heikki had a two-loft solution later in the thread. I'd really like to see THAT one. Congratulations, man... I am looking at the damn thing and still can't see how you can get it out of only two lofts. And here I thought I knew a little something about SWx... Ed

The two lofts are the only sketch driven features. There is a little more to it than that. This guy knows solid geometry.

By the way there is also a way to make this thing using folded triangles. I haven't quite worked out how to get that in SWX though.

For a tie breaker I might have to use rebuild time.

Ed,

It sounds like you have something interesting too. Can't wait to check it into the official Model Challenge PDM system.

snipped-for-privacy@juno.com wrote in news:1142306825.301229.308720 @i39g2000cwa.googlegroups.com:

I submitted a second entry last night...

Now that made me nervous... I sent another model, since lofts are actually a bad, very bad idea...

It is kind of interesting how much a model like this can be optimized with some thinking.

-h-

Dale,

I couldn't believe it when I saw it. If someone can do it in one feature they might beat you.

"TOP" wrote in news:1142360029.658213.59820 @i40g2000cwc.googlegroups.com:

One feature... I have an idea....

Sounds like I have to update my model. I think I can do it with one sketch (total), but still have four solid features (revolve, extrude-cut and two patterns) and no equations. Can't wait to see Dale's Model

-Ed

Ok, did I miss something,.. making a golfball with one feature?? And, where are you guys sharing your models, what url?

..

Sounds like I have to update my model. I think I can do it with one sketch (total), but still have four solid features (revolve, extrude-cut and two patterns) and no equations. Can't wait to see Dale's Model

-Ed

Dale,

One unexpected result is that several have submitted more than one solution. I have my own solutions that are different (and not as good as) some of you. Since some are having fun with two or three solutions, why not allow more than one? Just take time for your family and all that. The number of solutions so far are certainly adding to the art and science of modeling.

Now as for the vary the edge part I had the thought that one property of the truncated icosahedron is that all the edges are equal in length. But they don't have to be. Granted it wouldn't be a proper Archimedian solid, but it would be real world. One of the things you find in the literature is a connectivity graph between vertices and edges. Imagine that the restriction of having equal length edges were lifted, but not the connectivity requirement. Let's say that next month's challenge might be creating a solid of this type (though not necessarily this one) with the abillity to vary individual edge lengths by say +/-10%. I've had some thoughts on how to get there, but I'll keep them to myself.

Hello Paul,

Ok, honestly,.. I have a icosahedron and dodecahedron I did in ~2001-2002 (16 and 19 features respectively) but how are you guys doing

1 or 2 features to create a golfball, cuz, it's beyond me!? So, my question is, without learning (stealing) something from someone's prowess,... give me/us a clue!?

hmm,... are you guys drawing a 3Dsketch (one feature) to create cage and,.. add a few more features??

.. 8^)

Ok, that is what I was missing, you're doing a soccer ball! It's not clear because the thread is broken, you guys should have included the rules in the new thread...so, after looking back, I can see the rules now! ;^)

..things that make you go,... hmmmmmmmmmmmmmmmmmmmmmm.... 8^)

How about this for a start:

Since SW is a SolidModeler why not try modeling a solid, an Archimedian solid. Here is a link to the truncated icosahedron. see

for a definition. A. The model must be circumscribed by a 1meter spherical surface (transparent). B. Changes to the circumscribing sphere must correctly change the truncated icosahedron.

Here are the rules (subject to change as agreed upon):

1. Send an email to TOP via google groups when you start. The subject should be MARCH2006 Model Challenge.
2. TOP will reply and return a real email address and with any necessary files or information.
3. Complete the challenge
4. zip and send back to TOP

Criteria:

1. Correctness
2. Fewest features (including sketches)
3. Simplest
4. Robustness
5. Models that work without equations or design tables preferred
6. In the case of anything like a tie, first one done and vote by the NG.
7. This is for fun, please indicate how much fun you had on the submission.

..

I ended up with the same situation, but when I read this I decided to remove the last circular pattern. So my model has now one sketch, revolve, cut and circular pattern and no other features such as reference geometry.

-h-

It seems, though, that my second contribution with 5 features is more than seven times faster to rebuild than my last effort which has only three features.

-h-

Aha! Good one! I had 3 features, but two sketches and an axis. I think I see what you did. Yes that worked...A revolve, a cut, and a circular patterns with only one sketch and no axes.

Heikki's got me beat. I think I see now what he did, and it's definitely tighter that what I had. He used an option for the circular pattern I had forgotten about, which got rid of my one axis.

"Paul Salvador" wrote in news: snipped-for-privacy@mygate.mailgate.org:

We're making a truncated icosahedron, inscribed in a Ø1m sphere. Submissions are emailed to snipped-for-privacy@cbd.net, and he'll post them when it's done. Good luck doing better than Heikki.

Here's a link to Paul's (TOP's) original post, which is in another thread: