March 2006 Modeling Challenge

Comments anyone?

Sure, I'll start.

I think that this challange has shown once again the amazing differences in thought process. One of my favorite things is to see how peeps go about making things in SolidWorks (and how it differs from how I would do it), and this is a great example.

Thanks to the four contestants and to you TOP as well; Very enjoyable.

Muggs

Ed converged on an answer similar to the one Dale and Heikki did and then he completely diverged with his second solution.

I hope people also look at rebuild times as this is even more amazing that the contestants approaches.

Muggs wrote:

Fixed Link to Ed Eaton's model. This one is real interesting.

Only one comment so far but I'm sure many have had a look. I'll have to pick a winner by the end of the week but I was hoping for some moral support in the form of a discussion. So let's start off by discussing performance. There is a big surprise.

The top performing models had times of .25, .28, .3 and .46 seconds on my system. Obviously these times will be different on your systems. Times were taken from TOOLS/FEATURE STATISTICS. TimeLord's model with

31 features was the fastest, Dale Dunn's "Truncated Icosahedron" with 15 features was second, Ed Eatons "buckeyball fastest2" with 5 features was thrid and Heikki's TruncatedIcosahedron2 was fourth with 9 features. The average rebuild time for all models was 1.01 seconds with a standard deviation of 1.29. Maximum rebuild time was 3.66 seconds for Heikki's TruncatedIcosahedron4 with 5 features. If we deduct the surface feature this model actually had the lowest feature count to get the truncated icosahedron. So why was the performance so much slower? Heikki's TruncatedIcosahedron2 used a very similar sketch with very similar relations and had a very quick time. The sketch in 2 took .32 seconds and in 4 took .5 seconds. Dale's Layout sketch took .09 seconds and Ed's sketches took far less time to solve being .06 and .01 seconds. For some reason the circular feature pattern in Heikki's #4 took a lot more time than in his other models. Heikki's sketches have more relations and include symmetry and sketch patterns. Dale's and Ed's sketchs have fewer relations. These may be the culprits in terms of performance.

The question remains as to why TimeLord's model was so fast even with so many features. The answer seems to be that his sketches were very simple and didn't even show up on the Feature Statistics radar. Most features that had measureable times were in the .02 second realm and the longest feature was .06 seconds. Clearly many simple sketches and features can give a speed advantage.

T> Well the models are now posted. I'll hold off comment till others post. >

Thanks for the breakdown TOP, it's hard to a draw definitive conclusion from just the one challenge regarding performance. I eagerly await future challenges and more importantly your breakdown of performance.

John Layne

Just logged back on to your site to look at the images, most of the links are now dead.

John Layne

I'm not seeing any dead links. Clicking on the screen shot should cause a zip file to download. The zip file contains the model for that screen shot.

My apologies, Firefox was playing up for some reason -- cleared the cache and all images returned.

John Layne

I just got back into town last night... Went to see the folks and pick up my new GS850L 1980.

I love these little contests, and seeing all the different things people do. I'll have to stufdy Ed's sweeps, and his layout sketches too. A completely alien mind... This solution seems the most elegant to me. But what is that extrude at the end for?

A theory of why TimeLord's model solves faster... He doesn't seems to throw away any faces. At a guess, my patterned cut throws away more than half of the faces it creates. (A TimeLord indeed. I think he hid a Tardis in the origin.)

Thanks TOP for pulling these together and analysing. As for judging, I'd like to suggest two categories: rebuild speed and economy of features. These two must always be balanced, and balanced differently, while working on paying projects, so I think think we should not attempt to enforce an artificial balance by trying to merge them as a judging criteria. Furthermore, each is worthy of inquiry on it's own.

I'm looking forward to the next challenge, though I may not have spare spare time until after 07 beta and pre-release finish. Or will you accept entries from the beta next time?

Dale,

Run feature stats on each one and you will see what takes time. No need for theories.

What is worth pursuing is eliminating sketch relations one at a time till the sketch times come down.

I think I'll wait till after beta for the next challenge. No need to compete with the mothership.

I'll probably have to have several awards for various aspects and the original criteria will have to be kept just for consistency. But we'll all have fun. :)

Dale,

And BTW, that extrude on Ed's buckey ball is to close a tiny hole that needs must be there to make the sweep work. View the ball in hidden line while rolled back to before the extrude.

No, that would make too much sense.

Your turn. Why not analyze the differences in the layout sketches?

"TOP" wrote in news:1145453265.433592.242620 @v46g2000cwv.googlegroups.com:

"I think I'll wait till after beta for the next challenge. No need to compete with the mothership."]

Seriously, the layout sketches were pretty radically different. First I want to study how they were being used. Maybe in that process I'll figure out why one is faster than another.

You guys are all winners! I finally got a chance to look at the models during my lunch break. I am amazed.

It does seem that Time Lord and Dale Dunn in his first part violate the Euclidian spirit of doing things with Dale's 10.812... degree taper and Time Lord's 10.812... degree plane tilts and the .979... factor in the equation for sketch 2. I don't suppose that was really part of the rules, but it would be nice if everything you need to build the part would be included in a sketch, as in the rest of the parts.

Jerry Steiger Tripod Data Systems "take the garbage out, dear"

Jerry,

Well I am trying to stay within the Euclidean spirit of things, but I have to hand it to TimeLord that his model was blazing fast and that was probably one of the reasons.

The models really are amazing in breadth of approach even at the sketch level. I don't think the number of ways this could be done has been exhausted either.