The Black Box

Over the years, I’ve managed to keep in touch with some of my old college classmates and even one or two teachers, as well. We live in different countries now, so we usually exchange a quick email or, if we are lucky and have some time to spare, we chat for a while on MSN messenger.  The other night, I found one of my old teachers online. Back in the day, he used to teach Electric Power Transmission and Distribution. Now he teaches Advanced Math Methods for engineers.  We talked for a while about this new project that he’s working on and that, according to him, will dramatically improve the learning experience for the students in his class. It’s really nothing new or complicated, but it almost sounds evil.

You see, the way they teach Math in college nowadays is not precisely the way it used to be for some of us “old timers”. My friend says the students in his class use very powerful Texas Instruments calculators, that should serve as an aid in understanding and applying the different Math concepts that are exposed every week in the classroom. He wonders, however, if the learning process is actually happening in the ways it is expected, that is if the students are actually grasping the concepts, or if they are merely learning to use the calculators as a black box that will get them answers without having to think much or not at all.

With this in mind, he’s come up with the idea for the following experiment: he will simply forbid the use of such calculators during the next test they have. Only regular scientific calculators will be allowed, pretty much like those old CASIO ones we used to have back then and that nowadays, I believe, may be found inside especially marked boxes of corn flakes cereal. Pure evil, I know, but he’s actually convinced of the scientific value of his methods and has even recruited the help of a psychologist friend that will be present during the evaluation to assist him in recording and measuring the students’ reactions. Well, good luck with that! 

While I don’t agree with my friend’s methods, I think I can see his point. When you have a powerful tool in your hands, it’s sometimes easy to forget that it’s merely supposed to assist you, not to replace your knowledge and good judgment. It’s not supposed to think for you.

SolidWorks is not the exception to the rule. Here and there you are going to find little wizards designed to assist you in your job while you create or edit your part, assembly or drawing. For the most part, these are very useful tools, but you are still expected to use your best judgment.

Consider the SketchXpert, for instance. It’s designed to help you diagnose and repair relation problems in your sketches, but it won’t give you one perfect answer that will automatically solve the situation for you. In fact, what it will do is help you identify the relation or dimension that is causing trouble, but you will still need to decide over what to do, like in the following example.

In this sketch, I have deliberately applied unnecessary relations and dimensions to make it overdefined.  The SketchXpert dialog box opens, but it would appear as if the whole sketch was full of errors.  If I choose Diagnose in the dialog box, it offers me a couple of possible solutions by deleting relations or dimensions in the sketch. In the image below, solution number two involves deleting the dimension Radius5, which corresponds to the arc highlighted in green.

If I choose Manual Repair instead, what I will get is a list of all the relations and dimensions that are in conflict or have errors in the sketch, so I can manually choose those ones that I want to delete. This needs to be done with some caution and common sense; you definitely don’t want to delete dimensions or relations that are important for your design intent.

If you are unsure, you can simply suppress the relation or dimension by selecting it on the list and checking the Suppressed option at the bottom of the dialog box. This will allow you to see what would happen if you deleted that particular relation or dimension. When you are done evaluating that particular choice, you can easily unsuppressed it and go back to the list by clicking on the icon that looks like a curved arrow. In the following image, I chose to suppress the dimension of the arc that appears highlighted in green. Notice how the dimension appears in grey in the graphics area, and the sketch is now able to find a solution.

Like SketchXpert, there are many other tools and little wizards that may make your life easier or cause you a lot more trouble (COSMOSXpress, for instance), all depending on the way you use them. So, I guess my friend is up to something, after all.  We can’t allow our tools to become black boxes, no matter how powerful they are. They will do all the tedious work for us, so we don’t have to, but we’re still the ones that make the important decisions and we are still required to think.