This rocks, and congrats!
3D printed mirror array
101–110 of 152 posts
Re: 3D printed mirror array
#102Has anyone seen the mirror array that was built with ~2"X2"stainless steel mirrors that are attached to a sheet of blue spring steel that was laser cut as a compliant mechanism for each mirror so when an offset wheel on a threaded bolt behind the mirror is turned it progressively tilts the mirror from a minimal angle to a maximum angle? Each bolt was then driven using a single stepper motor(one mirror adjustment motor for the whole array, kind of a budget build, instead of one motor per mirror)on a belt driven x-y frame. The mirror array was positioned horizontally 2' off the floor of a museum with works of art, a camera is then pointed at an angle near eyelevel probably 20' away from the array. Then you choose an art work and the mirrors are rotated through their angles and when that pixel(mirror) reflects the color back to the camera that matches the art work you chose it stops moves to the next mirror and then repeats until there is a full image made of reflected light. Obviously the final image is pixelated but roughly resembles the original work. I saw this years ago and can no longer find any of it online. I've tried every search combination I could think of. Some of these details might be wrong but I'm just going off memory here. Pls help
Re: 3D printed mirror array
#103Has anyone seen the mirror array that was built with ~2"X2"stainless steel mirrors that are attached to a sheet of blue spring steel that was laser cut as a compliant mechanism for each mirror so when an offset wheel on a threaded bolt behind the mirror is turned it progressively tilts the mirror from a minimal angle to a maximum angle? Each bolt was then driven using a single stepper motor(one mirror adjustment moto…
It sounds like a Danny Rozin piece
https://en.wikipedia.org/wiki/Danny_Rozin
Edit; I'm sure it could be https://www.smoothware.com/danny/mirrorsmirror.html
Re: 3D printed mirror array
#104Has anyone seen the mirror array that was built with ~2"X2"stainless steel mirrors that are attached to a sheet of blue spring steel that was laser cut as a compliant mechanism for each mirror so when an offset wheel on a threaded bolt behind the mirror is turned it progressively tilts the mirror from a minimal angle to a maximum angle? Each bolt was then driven using a single stepper motor(one mirror adjustment moto…
It sounds like a Danny Rozin piece https://en.wikipedia.org/wiki/Danny_Rozin Edit; I'm sure it could be https://www.smoothware.com/danny/mirrorsmirror.html
These are close but it was definitely horizontal these are vertical. Thank you for the links!!
Re: 3D printed mirror array
#105Now how could we achieve the same thing with just origami?
https://jwst.nasa.gov/content/features/origami.html
Re: 3D printed mirror array
#106What happens if you point all the mirrors at the same spot? Fire?
Re: 3D printed mirror array
#107What happens if you point all the mirrors at the same spot? Fire?
Archimedes famously used mirrors to burn a fleet invading Syracuse: https://en.wikipedia.org/wiki/Burning_glass
Re: 3D printed mirror array
#108Earlier quoted context omitted.
An application close to this idea: IKEA arrow signs projected on the floor. They need no painting, floor needs no protection or treatment and they won’t disappear until the light is off.
You can do that just with a mirror in the shape of an arrow. Or a mirror with a negative arrow painted on it :)
Yes. It's pretty interesting they went the "projector" way.
I guess there is an issue of the arrow not being lit enough to stand out if the mirror flatly reflects ambient light, it would need to focus a lot more light, which would also make it much bigger.
It might also be that the additional light from the arrow is just beneficial in that specific case.
Re: 3D printed mirror array
#109Earlier quoted context omitted.
Aluminizing it would be way cheaper than silver. For that matter, you could probably glue down pieces of aluminized mylar rather than using mirrors, since you all you need is a spot of light, not a full-blown mirror image. Aluminized mylar is pretty cheap!
Bare aluminum would oxidize in a very short time to something dull. It would still reflect light but not quite as good. Aluminized Mylar would definitely work, but that's not bare aluminum but aluminum with a shiny layer over it to keep it clean. Very useful stuff, I built huge solar concentrators with it. 1000 suns on an area the size of a poststamp. You can do some pretty crazy stuff with that kind of energy densit…
You might need a micron of thickness of aluminum or silver. This piece looks like it's about 300 mm x 300 mm, which would work out to 90 mm³ of silver (or aluminum), which at 10.5 g/cc would work out to 950 mg of silver. Silver currently costs US$25.25 per troy ounce, so this would be 0.12¢ (US$0.0012) of silver, or somewhat less of aluminum.
Both silver and aluminum will tarnish if exposed to the air, silver more slowly but much more completely.
The process for silvering things is a lot easier to do at small scales than the process for aluminizing them. Aluminizing things normally requires a fairly good vacuum, and, moreover, a vacuum chamber large enough to fit whatever you're aluminizing. Perhaps someone will come up with some kind of convenient wet process for doing it but I'm not hoding my breath.
By contrast, you can silver glass with Tollens' test, using distilled water, silver nitrate, concentrated aqueous ammonia, hydroxide of potassium or sodium, and a reducing sugar (almost any sugar that isn't sucrose, for which you can substitute numerous other chemicals, such as formaldehyde, formate, isopropanol, or tartrate). This is commonly done as a classroom demonstration in chemistry labs nowadays, and it was done on a large scale almost 150 years ago for telescope mirrors. Nitric acid is beneficial but, unless you have to make the silver nitrate, not essential.
This is why it's much more common for amateur telescope makers to silver their mirrors rather than aluminizing them.
Re: 3D printed mirror array
#110Earlier quoted context omitted.
Word of warning: https://en.wikipedia.org/wiki/Aqua_Teen_Hunger_Force#2007_Bo...
That piece was done by my (then) neighbor. It was a little unnerving to come home to a dozen black Suburban SUVs parked in front of my house.
What have you been up to that would lead to such an unnerving response? ;-)