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Archive for July, 2008

This is about the wrong way to profit with people’s hunger for knowledge and need for information.  I know, it’s a rant, but I just couldn’t let it go without saying something about it.  Recently, our friend Jeff Mirisola, from the SW Blogging Squad, had voiced his need for suggestions and information regarding piping and routing with SolidWorks.  I really have no idea of how to use this functionality, but I grew curious about it, since it had also been mentioned by Matt Lombard some time ago.  For that reason, and trying to help Jeff, I began searching for a new or used manual, if there was any. I didn’t find anything on eBay, or any of the used books websites where I’ve found some useful stuff in the past. I did find a website  where a SolidWorks user was offering for sale a manual that he wrote himself, but there’s no way to buy it from his website at this moment. Apparently, he went out of town and closed sales for the time being.  I sent him an email and got no answer. So, yes, I found a manual, although not really.

Far from giving up, I decided to search in a different language and among websites for online trading and shopping, like eBay, but for people in Spanish speaking countries. I figured that a manual or book in Spanish or Portuguese was still good enough, even if it wasn’t such a good translation, as it’s often the case with technical books. Well, I found manuals, alright. I found plenty of them and tons of information too. In fact, I found several websites maintained by people in Spain where pdf files of manuals and even some famous SolidWorks books were being “shared” with their members. That was bad enough, but the worst part was when I arrived to a website where a guy was offering manuals, videos and other training materials, that, as it was understood, he had created. The materials were protected by a password that you could only obtain by joining his club and forum or by contacting him by email or phone. Of course, joining his club means that he gets to advertise all kinds of stuff to you, and/or collect some money from you to allow you to access certain areas. Thinking that he may be a legitimate author, like the other guy that wrote the manual, I joined the forum and downloaded one his manuals. Well, I bet you already figured out he was not a legitimate author. His manual was an old 2005 SolidWorks training manual, in English. He removed all the copyright information from it and added a watermark with his name and logo of his site. 

In this and other websites I also found SolidWorks videos that I recognized from other blogs, and from the CADJunky. I found videos I had made!  They had been edited to remove credits to the original authors and the sound removed, because they were originally made in English.  I know it’s not like I have a copyright for my videos. I mean, I don’t write or create videos with the idea of profiting from them, so I’ve never been concerned about limiting access or distribution to anything that is on this blog. I don’t care if someone wants to copy it and give it to some friend, but I think it’s nice to at least get some recognition from your work. It really stinks when you find it somewhere else and it’s being shared or even sold as someone else’s work.  Anyway, that’s my rant. Now back to more important stuff.

This is a little story that reminds me somehow about the way some of us approach SolidWorks and, more in particular, the new functionality that is added to it with every release. Read on and you’ll see what I mean.

One of the many summer activities for kids in this area is a one week bowling camp. It’s really fun and a great value for the money, because at the end of it all the kids receive a customized bowling ball of their choice and a bag.  My older son tried it last year and loved it, so this year we decided to sign up both boys for the camp. Now, you have to keep in mind that my younger son is only four, and his hands are so small, his fingers so short, that not a single one of the house balls in the whole bowling alley could fit him. The space between the holes for the fingers and the thumb has always been too large for him. For this reason, in order to bowl with the others, he holds the ball with both hands, gently places it on the lane and gives it a little push, then stays there, watching his ball slowly creep to the pins, at an “astonishing” speed of  1.5 mph.  Problem is, unless he’s allowed to use bumpers, the ball almost never makes it to the pins,  and usually ends up in a gutter, as a dead ball, instead. As the camp came to an end, we could hardly wait for him to try his new ball, the one that had been customized for him, using exact measurements of his hand and fingers.  The coach gave him his ball, and he placed his fingers and thumb inside the holes to hold it. He was so delighted! “It fits, mom! Finally, I have a ball that fits! Now I can hold it!” he said. Suddenly, it was his turn to bowl and what did he do? Well, while still keeping his fingers inside the holes, and as everyone cheered for him, he carried the ball all the way to the lane… then gently placed it down and gave it a push with both hands.  Oops!   I guess it’s going to take some time for him to realize he doesn’t need to do it that way anymore. He’ll get it in the end, I’m sure. I’ll make sure he does!

But, you see, the way my son continued to cling to his old ways even with the new and improved ball, reminds me a bit of all of us. Here we are with our “brand new ball”, this powerful software, full of functionality and great features, yet, many times we don’t use any of it, or don’t even know of its existence.  Instead, we continue to “give our ball a little push” in order to get the job done, just like my son did. And if you don’t believe me, go to the forums, read a few blogs, or check out the videos I posted of the last Tri-Valley SWUG meeting. You’ll see many users that seemed surprised to hear about top-down modeling, smart components, mate references, etc. Functionality that is not precisely new.   I wonder why. Is it lack of information about this functionality? Lack of educational materials? Misinformation? Lack of trust that this functionality may actually work the way it’s supposed to? Is it that we can’t come up with a good use for it? Or is it just that it’s too hard to get out of our comfort zone and try something new? Whatever the reason, it is a real shame. After all, what good is all this functionality, all this power, if we don’t use it?

So, next time you’re using SolidWorks, if you have a chance, try something new, just for fun. Explore a bit! You may be surprised by what you find! It may be just what you needed all along to stop pushing your ball down the lane and knock down a few pins for a change!

The next meeting of the Tri-Valley SolidWorks Users Group will take place on September 10^th, in Dublin, California, and it already promises to be a really special one, because this time, in addition to all the useful information and tips and tricks that we all look forward to (Kenneth will be presenting the deconstruction of a vaccum chamber just as he promised some time ago), there’s also an unusual treat: we’ll get to have with us no other than Richard Doyle, as well as a team of developers from SolidWorks!  That’s right! A team from SolidWorks R & D will be here to hold a Round Table discussion with the members of the Tri-Valley SWUG. How cool is that?! Well, think about all the questions you’ve ever wanted to ask to them, and all the suggestions and/or enhancement requests for future releases that you’ve only wished you could personally voice to them. Think about them! Think, but don’t just waste time thinking.  Rather than that, RSVP with Kenneth Barrentine today and attend this meeting if you happen to be in the area. You don’t want to miss it! For complete details on the meeting’s agenda, directions, or to RSVP, visit the Tri-Valley’s SWUG information page.  Hope to see you there!

This week is exciting, as I finally venture into the world of finite element analysis through COSMOS Works.  I have waited for such a long time! Unlike many young engineers nowadays, I didn’t receive a foundation on finite element analysis while in college.  Sure, we did have a class on numerical methods, where finite element methods were briefly discussed, but nothing else. Years later I had a brief encounter with a demo version of ALGOR, while my boss was evaluating their software, considering whether to buy it or not. The examples they provided really blew my mind. I had never seen anything like that! Unfortunately, my experience was cut short when my boss decided not to buy the software, since he couldn’t see any practical use for it. It didn’t matter much; I had already been bitten by the FEA bug, and wished really hard that someday I could learn more about it and become acquainted with software such as that one. Fast forward to these days: I’m still crazy about learning FEA, and this time I’m doing a bit more about it than merely wishing.  Here I am, trying to teach myself some FEA and COSMOS Works at the same time.

Of course, my very first experience had to be with COSMOSXpress, which is similar to COSMOS Works, but very limited in capabilities. I have the impression that these limitations, plus the fact that it’s so easy to use and everything takes place “automagically” behind the scenes may make it appear a bit fishy to some, but I have to disagree. I think the usefulness and reliability of FEA software such as COSMOS Works has a lot to do with the way we design our study, as well as how we interpret the results obtained from it. While it’s true that it wouldn’t be wise to take these results as Gospel for a final design, and we’ll always need to do some other calculations and testing, I really believe that finite element analysis can save a lot of time and effort and bring us closer to a final, much better design. 

I don’t think I really understand all the Math behind the solution, but what I do understand is that, basically, a finite element analysis requires creating a simplified model where the original part has been broken down in smaller pieces, called elements. The points connecting adjacent elements between them are then called nodes, and for each of these nodes there will be a set of equations that describe small displacements at the element level and that will need to be solved simultaneously with those of all the other nodes in the model in order to determine stress distribution, for instance, in the whole component. This process is called meshing or creating a mesh, and although it occurs automatically inside of COSMOS Works,  the users still have the ability to control how this mesh is created, thus affecting the accuracy of the results.

So far, I’ve learned about two different kinds of elements that are available in COSMOS Works: Solid Element and Shell Element.  The solid elements are used to model, well, solid components, parts or assemblies that have significant thickness relative to the rest of their dimensions. The shell components are used to model surfaces, thin walled components, sheet metal parts, etc. Each one of these elements is available as a first order element (also known as draft quality) or second order element (known as high quality), depending on the number of nodes on each of their edges. Solid elements are also known as tetrahedral elements.  The following image shows a first order tetrahedral element on the left and a second order tetrahedral element on the right. Notice that the second order element has an extra node for each edge, and this allows its surfaces and edges to deform in a curvier manner, conforming more accurately to the model’s surfaces, fillets, rounds, etc. For this reason and because there are more nodes and equations involved, second order elements provide more accurate results than first order elements.

Besides selecting what kind of elements to use, it is possible to select how fine the mesh will be. In general, the finer the mesh, the better the results, but it will also require more time and computational resources.  The following image shows a coarse mesh of solid elements.

And here is the same component using a finer mesh.

I’m not completely sure, but I think this is something new for 2008, because I can’t obtain the same results when I try it in 2007: the ability of automatically combining and transitioning the mesh size for certain areas of the model with high curvature. Notice in the following image how the mesh is finer around the holes and transitions to a much coarser mesh for the rest of the model.

This option can be found by selecting Alternate for the Mesher, under Options, when creating the mesh.

There certainly is a lot more to learn about FEA and COSMOS Works, and the more I learn about it, the more fascinating it appears. I wonder about examples of real life use of finite element analysis to design products, and what other methods are applied in order to verify the accuracy of the results. According to some notes I was reading, finite element methods are not precisely new; they’ve been around for over 60 years or so, yet, somehow it seems like a novelty. Or perhaps it’s just a novelty to me? Is FEA something that everybody uses nowadays?

As I’ve mentioned a few times before, my husband’s job requires him to travel frequently, at least one week of every other month, usually to places in Asia, although he’s also been to England, France, Ireland, Netherlands, Australia… Well, you get the idea.  This time he’s in China, and trying to access my blog to no avail (he’s my one sure reader).  After quite a few failed attempts, and noticing that there didn’t seem to be any problems to access the blog on this side, I asked him to try a few other typepad blogs. No luck either!  A quick search on Google took me to this blog: RC Conversations, by Rebecca MacKinnon.  In a blog post from June 2005, she explains how all or at least most of typepad blogs have been blocked in China, apparently for political reasons, even if they don’t talk about China or its government at all! According to her post, no blogs from Typepad would be able to be seen, unless you are reading them using some proxy server, because even some readers and feed burners were blocked. And it seems it wasn’t only Typepad, but other blog-hosting services as well, such as Blogger and Blogspirit. OK, so that was June 2005… I wonder if what my hubby is experiencing while trying to access my blog from China is anywhere related to that massive blog blockage or if it’s related to the most recent internet crack-down measurements taken for the Olympic games, as detailed in this article by the Global Voices Advocacy. Either way, it’s sad, isn’t it?  I don’t even talk about China in this blog! All I want is to share about SolidWorks with them! Oh, well…