4 ms·

Mechanical Laser Show (2017) [video]

126 points by hammerbrostime 9y ago

iaw 9y ago
That is beautiful work. It may even be possible to set it up so that the movement has a more constant velocity along the path.
- darkstar999 9y ago
  Maybe a mechanical governor. https://www.youtube.com/watch?v=u3lEnbrp9pI https://www.youtube.com/watch?v=u3lEnbrp9pI
- gene-h 9y ago
  Well if you want the laser to produce better images then one needs to use the dark art of cam design. As it turns out, simply determining cam geometry necessary to go through all those points is not enough, one must also take into account the velocity, acceleration, and even jerk profiles(the derivative of acceleration). If one does not take these into account the follower being driven can't spring back fast enough and the follower does not follow the intended profile. Most automobile cams must be produced to very high tolerances in order to achieve low vibration. The fact that CNC machine tools move in discretized distances can cause problems in some cases.
  - bitwise-evan 9y ago
    Yes- just like you are saying, the intention with the Mechancial Laser Show was not to maintain a constant laser speed, but accelerate and decelerate the laser gently. You can see the mechanism by which that is done by pausing the video at https://www.youtube.com/watch?v=_dtBUiaAqRE https://www.youtube.com/watch?v=_dtBUiaAqRE Since the time taken to travel to each next point is constant, closer points together mean slower speed and spread out points mean high speed. You can see that the laser will slow down for taking the corners and speed up for the straights. There was no math behind this- I just eyeballed it but you could write software/math to help you determine the perfect spacing/acceleration.
21 9y ago
At the other end of the complexity scale: https://www.youtube.com/watch?v=n2bf8L7G6WE https://www.youtube.com/watch?v=n2bf8L7G6WE
- jacquesm 9y ago
  Nice trick to sync the movement of the balls with the lasers.
- ben174 9y ago
  Mind blown. Any idea where I can see something like this in person?
aphextron 9y ago
Aren't all laser light shows technically "mechanical"? As far as I know solid state optical beam steering is not a thing yet.
- cr0sh 9y ago
  If you google "non-mechanical laser beam steering" you can find some interesting work being researched (I don't think anything is commercially available, though).
  - ASalazarMX 9y ago
    > An alternative to an acoustic-optic modulator is the electroptic deflector. There are a few types but the readily available type uses a quadrupole electric field on a lithium niobate crystal. This generates a linear refractive index gradient in one plane that can be adjusted on a ultra fast time scale. This gives the ability to change the deflection angle of a suitably polarised beam propagating down the quadrupole axis. With fast pulse generators the deflection speed can be good enough to achieve deflection by several diffraction angles in perhaps 10 ps. This sounds like something Geordi LaForge would say.
    - aphextron 9y ago
      >This sounds like something Geordi LaForge would say. Precisely why optics is the coolest shit ever
  - dreamcompiler 9y ago
    You can do it nonmechanically by bending the spacetime geodesic of the light path with an electromagnetically controlled nano black hole. Pretty sure they're not yet available on Aliexpress, but probably soon.
- darkstar999 9y ago
  Non-electronically controlled.
JKCalhoun 9y ago
Wow, that is clever. I love when the parts have been around for a decade or so and then suddenly.... I tell my daughters, "Nothing new under the sun," all the time. I could be wrong from time to time.
- simooooo 9y ago
  Nah, just new to you :)
- kevhito 9y ago
  You should say something else. There is lots left to discover and invent.
eigenvalue 9y ago
Great explanation of the math, made it very easy to follow. And the joke at the end was a nice touch, I was totally waiting to hear about his SAAS startup...
slackpad 9y ago
Recently came across this DIY laser projector vid - https://www.youtube.com/watch?v=xszp5UQLB2g https://www.youtube.com/watch?v=xszp5UQLB2g. It's all mirrors and motors in there with some manual controls.
debt 9y ago
This is so damn cool my question is, why is this type of shit so damn rare? Like why don’t we see more instances of cool, low cost, big value hackery? Is it just too creatively difficult to summon these types of ideas idk
- bitwise-evan 9y ago
  Thank you so much for the kind words. I am the creator and love these kinds of projects. Check out another project I created along the same lines: TheArtBot.com If you are asking why not many people do these types of projects- you sounds like an excellent candidate to do one yourself! I have list of project ideas on my phone that I will add to at random times. Next time you think of a cool idea write it down and make it a reality!
akavel 9y ago
See also a recent submission: https://news.ycombinator.com/item?id=16273170 https://news.ycombinator.com/item?id=16273170 I wonder what's the story behind it, is it real or fake, and is there an original (non-gif) video.
- runlevel1 9y ago
  There is indeed: https://www.youtube.com/watch?v=mgIZrSlPuko https://www.youtube.com/watch?v=mgIZrSlPuko It was a show called LaserMan -- part of ElecTRONica, a nighttime event at Disney California Adventure promoting the release of TRON: LEGACY. Creator's site: http://www.theodari.com http://www.theodari.com
bitwise-evan 9y ago
Hi. This is Evan, the creator of Mechanical Laser Show. I am planning to present it at the upcoming Maker Faire in SF for a day so feel free to come by and check it out. If you have any questions, feel free to ask here.

iaw 9y ago

That is beautiful work. It may even be possible to set it up so that the movement has a more constant velocity along the path.

darkstar999 9y ago
Maybe a mechanical governor. https://www.youtube.com/watch?v=u3lEnbrp9pI https://www.youtube.com/watch?v=u3lEnbrp9pI
gene-h 9y ago
Well if you want the laser to produce better images then one needs to use the dark art of cam design. As it turns out, simply determining cam geometry necessary to go through all those points is not enough, one must also take into account the velocity, acceleration, and even jerk profiles(the derivative of acceleration). If one does not take these into account the follower being driven can't spring back fast enough and the follower does not follow the intended profile. Most automobile cams must be produced to very high tolerances in order to achieve low vibration. The fact that CNC machine tools move in discretized distances can cause problems in some cases.
- bitwise-evan 9y ago
  Yes- just like you are saying, the intention with the Mechancial Laser Show was not to maintain a constant laser speed, but accelerate and decelerate the laser gently. You can see the mechanism by which that is done by pausing the video at https://www.youtube.com/watch?v=_dtBUiaAqRE https://www.youtube.com/watch?v=_dtBUiaAqRE Since the time taken to travel to each next point is constant, closer points together mean slower speed and spread out points mean high speed. You can see that the laser will slow down for taking the corners and speed up for the straights. There was no math behind this- I just eyeballed it but you could write software/math to help you determine the perfect spacing/acceleration.

21 9y ago

At the other end of the complexity scale: https://www.youtube.com/watch?v=n2bf8L7G6WE https://www.youtube.com/watch?v=n2bf8L7G6WE

jacquesm 9y ago
Nice trick to sync the movement of the balls with the lasers.
ben174 9y ago
Mind blown. Any idea where I can see something like this in person?

aphextron 9y ago

Aren't all laser light shows technically "mechanical"? As far as I know solid state optical beam steering is not a thing yet.

cr0sh 9y ago
If you google "non-mechanical laser beam steering" you can find some interesting work being researched (I don't think anything is commercially available, though).
- ASalazarMX 9y ago
  > An alternative to an acoustic-optic modulator is the electroptic deflector. There are a few types but the readily available type uses a quadrupole electric field on a lithium niobate crystal. This generates a linear refractive index gradient in one plane that can be adjusted on a ultra fast time scale. This gives the ability to change the deflection angle of a suitably polarised beam propagating down the quadrupole axis. With fast pulse generators the deflection speed can be good enough to achieve deflection by several diffraction angles in perhaps 10 ps. This sounds like something Geordi LaForge would say.
  - aphextron 9y ago
    >This sounds like something Geordi LaForge would say. Precisely why optics is the coolest shit ever
- dreamcompiler 9y ago
  You can do it nonmechanically by bending the spacetime geodesic of the light path with an electromagnetically controlled nano black hole. Pretty sure they're not yet available on Aliexpress, but probably soon.
darkstar999 9y ago
Non-electronically controlled.

JKCalhoun 9y ago

Wow, that is clever. I love when the parts have been around for a decade or so and then suddenly.... I tell my daughters, "Nothing new under the sun," all the time. I could be wrong from time to time.

simooooo 9y ago
Nah, just new to you :)
kevhito 9y ago
You should say something else. There is lots left to discover and invent.

eigenvalue 9y ago

Great explanation of the math, made it very easy to follow. And the joke at the end was a nice touch, I was totally waiting to hear about his SAAS startup...

slackpad 9y ago

Recently came across this DIY laser projector vid - https://www.youtube.com/watch?v=xszp5UQLB2g https://www.youtube.com/watch?v=xszp5UQLB2g. It's all mirrors and motors in there with some manual controls.

debt 9y ago

This is so damn cool my question is, why is this type of shit so damn rare? Like why don’t we see more instances of cool, low cost, big value hackery? Is it just too creatively difficult to summon these types of ideas idk

bitwise-evan 9y ago
Thank you so much for the kind words. I am the creator and love these kinds of projects. Check out another project I created along the same lines: TheArtBot.com If you are asking why not many people do these types of projects- you sounds like an excellent candidate to do one yourself! I have list of project ideas on my phone that I will add to at random times. Next time you think of a cool idea write it down and make it a reality!

akavel 9y ago

See also a recent submission: https://news.ycombinator.com/item?id=16273170 https://news.ycombinator.com/item?id=16273170 I wonder what's the story behind it, is it real or fake, and is there an original (non-gif) video.

runlevel1 9y ago
There is indeed: https://www.youtube.com/watch?v=mgIZrSlPuko https://www.youtube.com/watch?v=mgIZrSlPuko It was a show called LaserMan -- part of ElecTRONica, a nighttime event at Disney California Adventure promoting the release of TRON: LEGACY. Creator's site: http://www.theodari.com http://www.theodari.com

bitwise-evan 9y ago

Hi. This is Evan, the creator of Mechanical Laser Show. I am planning to present it at the upcoming Maker Faire in SF for a day so feel free to come by and check it out. If you have any questions, feel free to ask here.