Until recently, computer-aided design (CAD) software was really only used by engineering companies who could afford to pay thousands of dollars a year per license. The available software, while very powerful, had a very high learning curve and took a lot of training and experience to master. But, with the rise of hobbyist 3D printing, a number of much more simple CAD programs became available.
While these programs certainly helped makers get into 3D modeling, most had serious limitations. Only a few have been truly open-source, and even fewer have been both open-source and parametric. Parametric CAD allows you to create 3D models based on a series of parameters, such as defining a cube by its origin and dimensions. This is in contrast to sculpting style 3D modeling software, which is controlled much more visually. The benefit of parametric modeling is that parameters can be changed later, and the model can be updated on the fly. Features can also be defined mathematically, so that they change in relation to each other.
Today’s engineers are just as good as the ones that came before, but that should not be the case and there is massive room for improvement. Improvement that can be realized by looking for the best of the world to come and the one we left behind.
Survivorship bias is real. When we look at the accomplishments of the engineers that came before us we are forced to only look at the best examples. It first really occurred to me that this was real when I saw what I still consider to be the most atrocious piece of consumer oriented engineering the world has yet seen: the Campbell’s soup warmer.
This soup warmer is a poor combination of aluminum and Bakelite forged into the lowest tier of value engineering during its age. Yet it comes from the same time that put us on the moon: we still remember and celebrate Apollo. It’s possible that the soup warmer is forgotten because those who owned it perished from home fires, electrocution, or a diet of Campbell’s soup, but it’s likely that it just wasn’t worth remembering. It was bad engineering.
In fact, there’s mountains of objects. Coffee pots whose handles fell off. Switches that burned or shocked us. Cars that were ugly and barely worked. Literal mountains of pure refuse that never should have seen the light of day. Now we are here.
The world of engineering has changed. My girlfriend and I once snuck into an old factory in Louisville, Kentucky. The place was a foundry and the only building that survived the fire that ended the business. It happened to be where they stored their professional correspondence and sand casting patterns. It was moldy, dangerous, and a little frightening but I saw something amazing when we cracked open one of the file cabinets. It was folders and folders of all the communication that went into a single product. It was an old enough factory that some of it was before the widespread adoption of telephony and all documents had to be mailed from place to place.
[Tallaustin] worked at Stratasys as an intern this past summer. They let him know that he was welcome to use their fancy industrial printers as much as he’d like. Not to waste such an opportunity he promptly got to work and designed an electric longboard, printable for a mere $8,000.
[Tallaustin] is presumably tall, and confided to Reddit that he weighs in at 210 lbs. For those of us who have had the pleasure of designing for FDM 3D printing, we know that getting a skateboard one can actually skate on without it delaminating somewhere unexpected is pretty difficult if you weigh 80 lbs, 200+ is another category entirely. So it’s not surprising that his first version shattered within in moments of testing.
So, he went back to the drawing board. Since he had his pick of all of Stratasys’s most expensive and fine spools of plastic, he picked one of the expensivest and finest, Ultem 1010. Aside from adding a lot of ribbing and plastic, he also gave it a full rundown with some of SolidWorks’s simulation tools to see if there were any obvious weak points.
Six days of exceedingly expensive printing later, he had a working long board. The base holds some batteries, an ESC, and a 2.4 GHz transceiver. The back has a brushless motor that drives a pulley slotted into one of the wheels. The rest is standard skateboard hardware.
If you’d like to build it yourself he’s posted the design on Thingiverse. He was even nice enough to put together a version that’s printable on a plebeian printer, for a hundredth of the price.
[ossum] had a stack of Amazon and Shapeways credits lying around after winning a few competitions. He had this dream of building an R/C car for a while, and decided now was the time. After ordering all the needed parts from Amazon, he made an extremely nice model of the car in Fusion 360. The CAD model is a great learning resource. If you want to learn how to use reference photos, parts, and more to build a detailed and useful CAD model we recommend downloading it as a Fusion archive and scrubbing through the timeline to see how he did it.
Some of the parts were sent off for laser cutting. Others were 3D printed. The rest he made himself. Thanks to his model, they all went together well. You can see his R/C rod racing in the video after the break.
On the Starship Enterprise, an engineer can simply tell the computer what he’d like it to do, and it will do the design work. Moments later, the replicator pops out the needed part (we assume to atomic precision). The work [Raf Ramakers] is doing seems like the Model T ford of that technology. Funded by Autodesk, and as part of his work as a PhD Researcher of Human Computer Interaction at Hasselt University it is the way of the future.
The technology is really cool. Let’s say we wanted to control a toaster from our phone. The first step is to take a 3D scan of the object. After that the user tells the computer which areas of the toaster are inputs and what kind of input they are. The user does this by painting a color on the area of the rendering, we think this technique is intuitive and has lots of applications.
The computer then looks in its library of pre-engineered modules for ones that will fit the applications. It automagically generates a casing for the modules, and fits it to the scanned surface of the toaster. It is then up to the user to follow the generated assembly instructions.
Once the case and modules are installed, the work is done! The toaster can now be controlled from an app. It’s as easy as that. It’s this kind of technology that will really bring technologies like 3D printing to mass use. It’s one thing to have a machine that can produce most geometries for practically no cost. It’s another thing to have the skills to generate those geometries. Video of it in action after the break. Continue reading “RetroFab: Machine Designed Control of All the Things”→
People like music, but they are also visual creatures. Perhaps that’s why music visualization is such a common project. Usually, you think of music visualization as using LEDs or a computer screen. However, [Gieeel] did his music visualization using a 3D printer.
Sure, the visualization is a little static compared to LEDs, but it does make an interesting conversation piece. The actual process isn’t very difficult, once you have the idea. [Gieeel] captured the waveform in Audacity, did a screen capture, and then converts the image to an SVG file using Inkscape.
From there, you can use many different CAD tools to convert the image into a 3D object. [Gieeel] used Autodesk Fusion 360 and had the resulting object professionally 3D printed.
I’ve taken lots of reference photos for various projects. The first time, I remember suffering a lot and having to redo a model a few times before I got a picture that worked. Just like measuring parts badly, refining your reference photo skills will save you a lot of time and effort when trying to reproduce objects in CAD. Once you have a model of an object, it’s easy to design mating parts, to reproduce the original, or even for milling the original for precise alterations.
I’m adding some parts onto a cheap food dehydrator from the local import store. I’m not certain if my project will succeed, but it’s a good project to talk about taking reference photos. The object is white, indistinct, and awkward, which makes it a difficult object to take a good photo for reference use in a CAD program. I looked around for a decent tutorial on the subject, and only found one. Maybe my Google-fu wasn’t the best that day. Either way, It was mostly for taking good orthogonal shots, and not how to optimize the picture to get dimensions out of it later.
There are a few things to note when taking a reference photo. The first is the distortion and the setup of your equipment to combat it. The second is including reference scales and surfaces to assist in producing a final model from which geometry and dimensions can be accurately taken. The last is post-processing the picture to try to fight the distortion, and also to prepare it for use in cad and modeling software.