CAD vs. Paper

wow Tom. What an unlikely place for a post like that. I can see how it applies to what we're talking about. Good luck and keep us posted

 

Very best of luck Tom. Here's to a full and rapid recovery.

 

Get well soon, tom28571.

 

Car exterior and interior surface design involves both computer tools and clay models. At least that was the situation in Warren, Michigan when I retired four months ago from a job which involved almost daily interactions with design center during the intial phases of numerous vehicle programs.

Initial sketching is done both on paper and on computer tablets, though the trend is definately towards tablets as the designers gain experience with them. After several rounds of sketching the initial computer models are generated. The computer models are evaluated in virtual reality at full size, and 3-D vision systems are sometimes used. Selected computer models are milled into clay 1/3 scale models which are then refined by hand. (Experience has shown the scale models need to be slightly exagerated in terms of curvature and shape, otherwise they look flat compared to a full size model. I suspect this is due to human binocular vision not scaling.) Meanwhile sketching/drawing continues, particularly around areas such as headlamps and grilles, wheel opennings, etc and the results worked into the clay models and/or computer models. The updated clay models are scanned and computer models created/modified to correspond to the clay models. The computer models are also used for engineering including creating the body structure, packaging the everything which needs to fit between the interior and exterior, and analysis including metal, polymer and glass forming, aerodynamics, visibility, ergonomics and so forth.

Eventually one or more designs are chosen to be made into full size clay models, and the process is repeated until a final design is chosen.

Math data is generally exchanged rather than clay models if work is being done on multiple continents then. The digital information can be milled if a physical model is needed in a different location.

Ten, fifeteen, even twenty years ago many folks thought clay models would be entirely replaced by digital models. That hasn't happened. What has occured is the virtually complete replacement of 2D drawings whether created by pencil and paper or CAD. About the only 2D "drawings" seen today are side view renderings and those are generally generated from computer models.

 

Yes, for model yachts.

Cheers,

Earl

 

That's an interesting account. Thanks for sharing.

I've been looking into a 'tablet' by Wacom called the Cintiq. There are some impressive videos on this device on Youtube. "only" $2000.

Earl, looked up some of the models at USVMYG. While one may be able to replace such a craft with stl or some other rapid prototyper, I can't imagine much that would be as fulfilling as creating a sailable model yacht by hand.

Cool stuff!

 

Car and boat design both share a common factor with a project I was involved in about 15 years ago. This was a large robotic dinosaur, which emulated virtually every joint in the body of a Triceratops. There were very few right angles in that machine, as the drawing of the internal skeletal structure or spindle shows. The detail was mind-boggling: even the retinas in the eyes could change size.

It's a while back and I may be wrong about some of the details but there were 26 or so hydraulic actuators, a similar number of pneumatic and electric actuators, and an obscene number of sensors all of which were connected to a remote control system, which itself was a multi-computer setup. The cabling alone filled a truck.

It would have been impractical to create such a design using classical orthographic views on a drawing board, and could not have been done with any real chance of success a mere 10 years earlier. All the parts went together first time, with just one small glitch caused by assembling the last few parts in the wrong sequence!

it was an interesting mixture of technologies, with wooden mockups, clay modelling, the skin was made using methods akin to masks used in movies, blue-screen and stop motion also from the movie business, to several top-of-the-line Sun work-stations for the dynamics, which ensured that all the required motions could be performed by the mechanism. Curiously, I used no advanced computer tools when I designed the computer and interconnection, just Powerpoint!

I still recall my utter disbelief when my company got this job, although we had been bidding on similar but less complex projects for a while, because normally we did large but more conventional robots for nuclear, space and other applications.

The control system was my job. I have been a dinosaur devotee from when I was a little kid, a long time ago as I have been retired for 10 years. The triceratops was my all-time favorite and I was delighted to be assigned this task for my last project before retiring.

 

Now you guys have me messin with the bezier curves in photoshop and I am as frustrated as I was when I first learned them in Illustrator in a computer cartography class.

Here is the ultimate answer to the CAD vs Paper debate.
"Save yourself the headaches either way and hire someone else to do it."

 

+1 for CAD all the way. I think that using any sort of ink/graphite/whatever on a piece of dead tree is quite prehistoric. Take the following example of what the future industrial design tools will be like:

1: Start with your old drafting table (1200mm x 800mm approx size) but it's not timber it's a touchscreen tablet (like an iPad).

2: on top of normal internet and computing tools is a fully functional design application. The one program would include, similar to the functions of; Autodesk Sketch Book Pro, Alias Autostudio, Solidworks, RTT Deltagen and Photoshop CS. If you are unaware of these applications then I suggest that you google them to better comprehend what this software can do.

3: consider this workflow:

Sketch your design with unlimited medium (and of course an undo ). If you are having trouble visualizing your sketch add some 3D curves and basic surfaces.

Finalize your concept in whatever preference you like. Customer likes and has some minor suggestions.

Create basic CAD model with basic rendering and suggestions. All good.

Finalize detailed model, this can be painfully time consuming but once you build / buy a nice library of components it will no longer be a chore.

Create photo-realistic rendering with full image based lighting, ambient shadows, custom environment etc in about 1 hour. Airbrush added effects. Looks almost too real. Send image to customer, very happy.

Could send the model off for analysis (computational fluid dynamics or whatever) if you felt necessary.

Send the cad data for rapid prototyping of a scale model. Now you know it floats.

Once you have blown away everybody involved with financial approval with your life like images displayed at 50,000 X 50,000 pixels and shown them something they can touch it's time to start building.

I would build a composite boat, so that's where the 5 axis mill replicates the model to the mm. Everything fits because every detail was digitally prototyped.

4: So before you say "he's dreaming", all of these tools exist. Just not in the one affordable package. When that does happen, and it will, the limit for me buying such a system would be 20k in today's dollars. Bargain. Look, most people would be completely bamboozled by such tools and they do take time to learn. But all of the features allow you to create exactly what you want with no limitations. Sure if I was using AutoCAD I would agree that only certain shapes can be created with that junk, but with NURBS that is not the case. Any curves and surfaces app with decent hardware shading ability is the perfect design tool IMHO.

Of course having a few CAD monkeys around helps. I hate spending too much time sitting at a computer.

Cheers

 

Something like this, maybe?



I really enjoyed the designing/making interfaces in 'Iron Man' too... I guess we have a little way to go yet.

 

wait till we get to warpable boat hulls that change shape to adjust to present conditions like the wing warping on fighter jet airplanes that eliminates ailerons and wing flaps.

 

I want to learn parametric, feature-based CAD, but suspect that I will most likely just hire someone out of school to do it for me. I will be the old guy pointing at the screen screaming "LIKE THIS" smudging my fingerprints all over everything.

 

Interesting experiences you have had, thank you for sharing.

 

AK, the retinas are the projection screens at the back of the eyeballs. The pupils will diminish in size as the irises contract around them. But I know what you meant to say.