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The Beckoning Promise of Personal Fabrication

posys noted an interesting talk from Neil Gershenfeld's called "The beckoning promise of personal fabrication". It's a TED talk which I've found greatly enjoyable in the past, and is worth your time, assuming you have 20 minutes to see something really neat. If you are interested, you can also return to the original TED page.

9 of 131 comments (clear)

  1. Re:The overrated promise of personal fabrication by spleen_blender · · Score: 3, Interesting

    You're not looking forward far enough. The future of personal fabrication machines lies with nanotechnology. Imagine downloading the schematic for a new video card, feeding in the raw material components, and watching the nanotech gobble it up and crap out a piece of engineering developed with precision at the molecular level.

  2. Re:The overrated promise of personal fabrication by Zackbass · · Score: 4, Interesting

    I agree with you completely. I'm a mechanical engineer and do a lot of prototyping and in my experience stereolithography is a very niche tool. We've got one in my lab and it's used a fair bit, it's pretty good for small plastic parts that must be made in 3D, but that turns out to be a surprisingly small section of useful parts. We've got a 120W laser cutter too, and it rocks. Material is cheap, the machine is extremely fast, and with a good designer almost anything can be made. This last month I made a small roomba style robot for a competition: 3 days in CAD, 2 hours on the laser cutter and 2 hours in the machine shop and I had a great machine, and I could make another in 4 more hours, and another ad nauseum.

    A part from any of these rapid prototyping machine is almost always useless by itself. You need hardware, motors, metal shafts, electronics, different materials, and some skill in putting it all together to make much of anything interesting. There might be a revolution, but it's for the people that have been fabricating for years anyway who are finding new and better ways to do the same jobs. I took a manufacturing class with one of the pioneers in applications for stereolithography, it's a useful process with some niche applications, but no revolution. It's no personal computer, life is a little harder when you're pushing around real matter instead of information.

    --
    You gotta find first gear in your giant robot car
  3. My biggest issue with these things.... by mark-t · · Score: 2, Interesting

    ... is lack of resolution. Until they can bring the accuracy of part making down to the order of a few microns, it's not going to really be that practical.... for crying out loud, even the human eye can resolve measurements of only 35 microns. They need resolutions at better than half that before I'd ever look at getting one.

    1. Re:My biggest issue with these things.... by TheDrop · · Score: 2, Interesting

      Tolerance and feature size are completely separate things. Tolerance refers to the accuracy of a part, where feature size refers to actual dimensions of a feature. Basically, this particular machine cannot produce parts/features below .01 inch but anything above that will be accurate to within .001 inch which is the claim you asked me to find a link for. Secondly, it is exactly an example of something suitable for on-demand fabrication that could be done in anybody's home. There are different technologies in rapid prototyping like fused deposition modeling (FDM), Stereo Lithography Apparatus (SLA), and Selective Laser Sintering (SLS) which are all likely candidates for personal fabrication. I linked to to the Solidscape machines because they are some of the smallest machines available and are used in dental offices for on-demand fabrication. They're a computer peripheral no larger than a printer (in some cases) that run off electricity. So why couldn't this be used in anybody's home? And your original comment simply said you don't believe the resolution is great enough for your purposes. You haven't said what your making, but if it's anything similar to an injection molded part the technology is readily available in resolutions at least as good as many mass produced parts, and is getting cheaper and better by the day. (Sorry about the long post, but I just want to relate a personal example. In college I owned a 98 VW Jetta which was known for a particular failure in a small plastic clip in window regulator assemblies. Basically, the plastic used in the clip did not respond well to temperature changes. When it eventually failed, the window would drop into the door panel and could not be operated. I took the vehicle in for service and could not purchase the plastic piece alone. Instead I was told I would have to buy the whole regulator assembly which I think was around $450. I couldn't afford it at the time, but had access to a rapid prototyping facility. I modeled the part up in solidworks in less than an hour, had it built in less than an hour out of ABS, and installed again in less than an hour. Part cost - $12. The part never failed and 3 years later I sold it like that to a friend who has never had a problem. There are numerous other examples - I've been asked on several occasions to model up fixes for Roomba vacuums and the problem is always solved cheaper and faster than traditional routes. My point is that most of what people may need to personally manufacture can easily be done today.)

  4. Re:do they apply? by jockeys · · Score: 2, Interesting

    Ummm, you can already make a reasonably complicated firearm on a home CNC mill, or if you are a skilled craftsman, an unguided mill. It just takes a long time and won't be as good as one made in a factory. As long as there are factories stamping Kalashnikov receivers out of sheet metal for a couple bucks a pop, there won't be a lot of competition in the weapon market from expensive, one-off fabs.

    --

    In Soviet Russia jokes are formulaic and decidedly non-humorous.
  5. Re:do they apply? by Unending · · Score: 2, Interesting

    As CNC mills get cheaper it's possible that AKs will become incredibly cheap to home produce. People already fold their own AKs from parts kits at prices that are cheaper than retail (time not included).

  6. Why so dismissive? by Phoenix666 · · Score: 2, Interesting

    3D printers that build structures with plastic beads exist. We also already know that it's possible to arrange molecules with a scanning-tunneling microscope. Why is it such a leap to imagine that process for complex structures could be automated?

    Yes, there are significant hurdles to overcome, but comparing the concept of 3D molecular deposition to a belief in magic dragons is off-base.

    It's important to strike a balance between luddism and vaporware, to be sure, but you're refusing to extrapolate logical successors to existing technologies because they exceed your personal sense of the possible. But others do believe it's possible, and they will keep trying to achieve it until one day they succeed.

    And you will work for them.

    --
    Do what you can, with what you have, where you are.
    1. Re:Why so dismissive? by Reality+Master+101 · · Score: 2, Interesting

      We also already know that it's possible to arrange molecules with a scanning-tunneling microscope.

      One single molecule.

      Why is it such a leap to imagine that process for complex structures could be automated?

      Now figure out how many molecules make up, say, a 10 cm cube of your favorite material. Sure, you could do it if you want to wait a million years.

      The only way things like this are even remotely possible would be with self-replicating robots, to do parallel assembly. But then you have the problem of a) self-replication, b) communication between trillions, if not quadrillions of robots, c) a power source, d) a precision way to move, e) the "sticky finger" problem, f) a useable machine at the scale of a single molecule that has to be MADE of molecules, eh, I'm sure I could keep going, but this is just off the cuff.

      Nanotech robots are actually less practical that Star Trek teleportation. At least with teleportation, you can wave your hand at an as-yet-undiscovered physics principal, but nanobots are just physically ridiculous. I suppose you could wave your hand and speculate about robots made of subatomic particles.

      Really, when you talk about nanobots and molecular-level assembly, you're talking about magic dragons.

      --
      Sometimes it's best to just let stupid people be stupid.
  7. OK, gear change abstraction by Animats · · Score: 4, Interesting

    The interesting question to me is what layer of abstraction did you have your gear change fix at?

    Somewhat off topic, but anyway... Gear changing was abstracted to "change to desired gear" at the Galil motor controller, which is a programmable device interpreting a simple little programming language of its very own. The higher level computers would send it a UDP packet with the desired gear number, and every 50ms, read back the status. During gear changing, it would report "busy", and once gear change was complete, the new gear number would be reported.

    We had a GUI for debug, showing various buttons and meters. The transmission was represented with "D", "L", R", and "N" buttons. The current gear showed in green. During a gear change the button turned yellow, then green once gear change was complete.

    At the next level up, the "speed server", running on a QNX machine, was responsible for throttle, brakes, and transmission. It handled the interlock conditions for gear changing (vehicle speed zero, brakes locked, RPM at idle). The speed server was basically doing a "cruise control" job. It also handled the "rollback" problem.

    The level above that, the "move server", took requests like "advance forward 20m at 3 m/sec with turning radius 30m", and issued commands to the speed server and steering system. The move server understood stopping distance, including hills, and had an input from the simple anti-collision radar to stop if a big obstacle was in range. Move requests were replaced with new ones every 100ms by the map system.

    At the level above that, the map server/planner, operating at "back seat driver" level, was in charge of deciding where to drive. It didn't have to worry about vehicle dynamics. It just decided when backing up was necessary, and issued a backwards move. This would result in everything winding down to the vehicle stopped/brakes locked/engine idle condition, a gear change, a brake release, and acceleration.

    We lost the Grand Challenge, but the vehicle drove itself and never hit anything. We had about +- 2 degrees of compass noise, and that was enough to get the LIDAR-built map out of sync. The vehicle would stop, rescan, rebuild the map, and recover, but that was too slow. We tried to get by without a $40,000 FOG gyro, heading from dual GPS phase, or SLAM, and that wasn't good enough.