Batmobile: Getting Started

So. This is a bit of a walk-through talking about how I modeled the Batmobile. Is it more entertaining than a $70 video tutorial of how to model an Audi R8? No idea. I do know it’s about $70 cheaper, though.

I wasn’t trying to be exact on the model. There were things I wanted to make a little differently, and some things that just turned out differently for reasons I can’t exactly identify. I just wanted to do it, so I just did it.

You have to decide early on just how much detail you can afford to put in. The cost is mainly in time. The detail comes later in the process, but having a time budget even for a just-for-fun project is important.

I started, like most of these things I do, from a set of images to place on planes. These particular images it might have been better to make them black and white, then invert them so you would have a white background with black text. Less junk on the screen.

To get these images, I scoured the internet for a while. Any time you are working with artist interpretations rather than actual photographs, you run the risk of various views not matching up. This is part of the reason why I had to do some interpretation: I didn’t have perfect reference material. Even when you are doing product design and the artist providing you with orthogonal views is supposedly on your side, you rarely get stuff that exactly matches up in all views perfectly.

Placing the origin is always a question. For me, I always have trouble lining up the bottoms of the tires for renderings, so the point of contact for the front tire is where I assign the origin. That means that if the rear tire is a different diameter, it is still easy to line up the rear tire so it doesn’t sink into the ground on the rendering.

You’ve got to use a size reference, which in this case was just a straight line representing the wheelbase. Then I applied a dimension according to the image, and scaled the images to fit. Remember, 1 pixel = 1 mm by default for these sketch pictures. Name these something obvious, and don’t put any sketch geometry in the sketches that you are going to use in other sketches. Otherwise, they will go somewhere other than the top of the FeatureManager.

I think that conceptually, the most difficult part of models like this is trying to lay out which features you will use to create which shapes. A very respected SW user once said that you shouldn’t think about features, or something to that effect. But I disagree. I think you have to think about features. You have to know which features can achieve which shapes. You also have to understand that the Trim tool can help you separate the useful part of a feature from the not-so-useful.

My next step was to decide on a face to start with. I like to start with the hood. Since this car really doesn’t have a hood, I started with the tops of the front fenders. To make this shape, I’m going to make a surface that is bigger than I need, but the right contour. Then I will trim it to the right shape.

Remember that the Boundary surface is magical. You can make surfaces from sketches in the shape of a T. Usually, a T would only make a sweep, but it makes Boundary surfaces well. You can also do an F, and whatever the letter would be called if F were mirrored about the vertical line in the F. Or an H where the center line is extended. That’s what I did here because it was the information that I thought I had. I didn’t need to give it more info.

Try to name planes and sketches, especially if you think you might edit this later or someone else will look at it.

Don’t work in perspective. Even if not working in perspective offends your finer artistic senses, SolidWorks sketching and dimensioning do not work very well in perspective. Plus, if you are such an advanced being, you should be able to compensate for the screen’s lack of perspective in your mind. Renderings need to be done in perspective, sketching and dimensioning don’t. Remember cameras use perspective by default.

Next I made the cowling for the jet engine. If you have all of your sketch pictures on, this can start to get a little overwhelming. Remember that in 2010, the Display Pane (flyout shown to the right of the FeatureManager) can help you control the display of bodies. This can be very helpful in complex models. You can also use it to turn off sketches. I think this is a great bit of functionality.

So now the jet cowl and top of the fender are complete. These two shapes are going to have to blend at some point. How to do that may be a tough question. This was something I had to settle through trial and error. I didn’t just make up my mind to do it one way and it magically worked the first time. I went back and forth on this. Don’t fool yourself. This is not an exact science.

A little bit on the trimming of the top fender shape. Remember that there are two ways to handle blends or fillets. You might have to model to a sharp and then fillet it, or trim back from the sharp and use other features to blend. The smoother the blend, the more you will have to cut back.

Next I added an interior to the inside of the jet cowl, and a side to the fender. I just modeled right over the wheel well, knowing that the wheel opening and flare will be added later. Some wheel flares are so extreme that they have to be modeled as part of the panel they are on, but that is difficult.

I’m looking at doing a Nissan 370Z, and the front fender flare is gonna be tough. It is all a single flow along with the front bumper and the side of the car, right up to the hood.

Next I added the inside of the fender. This is mostly a throw away surface used to make the transition between the fenders and the jet cowl. I have two vertical sketches and the single edge of the top fender to create a Boundary surface.

According to Mark Biasotti, you need to get in the habit of using Boundary. You have heard that before, but maybe you haven’t hear why. The thing is that Boundary is more accurate than Loft, and as we see later in this model, when you try to Knit together lofts, you might run into tolerance stackup problems. I know. You are used to thinking of your CAD models as being exact, and only worry about tolerances in manufacturing and assembly. But now we learn that the computer is not always as exact as we imagine it to be.

When using Knit, if you start getting strange errors, such as “there are no edges to knit”, try messing with the Knit tolerance settings. To make it work, generally a setting of .001″ will do it. At least it did for me. The physical size of the batmobile was about 20 feet.

Anyway, the last feature to deal with for this post is the front corner of the fender. This is one of those situations you should avoid, but in a case like this where we are just making a fun model, the degeneracy might be something we can get away with. In this case, I used two edges and a sketch. The sketch contains a spline with c2 to edges on both sides. I just try to allow the software do what is natural, which will be the thing most likely to work and look good. If you try to force a shape on it, that force fit may backfire on you.

Notice that each edge selection is actually a Selection Manager selection, where two edges are picked for each of the Boundary’s Direction 1 curves.

Ordinarily I would do something like this with a Fill, but for some reason, a Fill must not have given me the results I wanted. I spent a lot of time on this feature.

Come back next time when we will step through modeling the transition from the fender to the jet cowl, and you’ll hear Bat Lombard say “Holy 3D, Batman, this thing has handles!”