I wonder if inductive power transfer could be used to eliminate the need for a battery. It would only have to power the LEDs, not the motor as that could be mounted to the base. Additionally, both coils could be placed right inside of each other, and on a ferrite core.
Tiny volumetric display
121–130 of 180 posts
Re: Tiny volumetric display
#122Are micro LED panels commercially available yet? Seems perfect for something like this.
Re: Tiny volumetric display
#123Earlier quoted context omitted.
Free time is an excuse for most people - I'm not calling you out because I don't know you but most people spend a lot of time on YouTube - Hn - Watching TV etc and they could be working on a cool project instead.
Watching TV? YouTube? Sounds like your peer group is biasing you. How about struggling to work from home for 8 hours a day with two kids with zero familial support, an endless array of bills, and every possible life obstacle coming your way 24/7?
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Re: Tiny volumetric display
#124Why waste time with a bunch of discrete LED chips mounted at very coarse pitch when there are small LED DISPLAYS?
Re: Tiny volumetric display
#125One of those brilliant ideas that seems obvious in retrospect. Given that the results are so compelling even when pulled together by hand out of relatively primitive discrete components, I’m wondering why we shouldn’t expect to see full color, high resolution versions from every random 7-letter drop shipper on Amazon next Christmas?
for a 32 inch display, you gonna get a motor that may need to spin like a mofo in an area of pi*32^2.
I’ve seen 1kW Chinese closed loop servomotors, with driver for < $500. And you don’t care about acceleration, just continuous torque.
Re: Tiny volumetric display
#126A couple ideas for improvement. If you have extra identical motors and disassemble two, you can fashion a rotating power transmission system from the brushes in two assemblies. You sacrifice two motors for each unit, but it's a perfect fit and very reliable (with a cap and rectifier), and you don't have to worry about batteries anymore. The rectifier also provides a signal that the assembly has completed a rotation,…
Another idea: why not put a tiny TFT display on the motor? You can get cheap ones at aliexpress.
Re: Tiny volumetric display
#127I wonder how much this could be improved/sized up.
Each pixel on such a setup travels along a circle. Spinning at 1200 rpm = 20/second, a 1000 Hz display would have a resolution of 50 segments along this circle. With a 10 cm diameter, this would make the outer "pixels" in the virtual 3D display around 6mm long.
The outer edge of the display would also experience a force of 80 G at that point, so bigger and/or faster spinning quickly becomes challenging (although it's only linear).
Driving monochrome OLED displays at 500+ Hz has already been done https://blog.adafruit.com/2012/02/03/adafruit-ssd1306-monoch...
Re: Tiny volumetric display
#128A couple ideas for improvement. If you have extra identical motors and disassemble two, you can fashion a rotating power transmission system from the brushes in two assemblies. You sacrifice two motors for each unit, but it's a perfect fit and very reliable (with a cap and rectifier), and you don't have to worry about batteries anymore. The rectifier also provides a signal that the assembly has completed a rotation,…
Another idea: why not put a tiny TFT display on the motor? You can get cheap ones at aliexpress.
Would be cool to see how that would look like. Or even a transparent OLED or such.
Re: Tiny volumetric display
#129Earlier quoted context omitted.
Interesting. My electronics work-bench is right next to my work/personal computer, so when I block on work stuff I can switch to doing a little on my electronics projects. It's made me much more productive.
I'm just too easily distracted. I start on a thing that I think will take five minutes, next thing I realize that it's 7 am, birds are tweeting and there is a stone cold cup of tea sitting next to me and a bunch of non-priority stuff done (but it's so much more fun...). Most dangerous times: when the administration needs to be brought up to date for the tax man. Then I really have to force myself. Fortunately I've be…
Isn't it great how you grab the soldering iron (or whatever) at 2 am for a quick thing, and five minutes later it's 7 am?
Re: Tiny volumetric display
#130A couple ideas for improvement. If you have extra identical motors and disassemble two, you can fashion a rotating power transmission system from the brushes in two assemblies. You sacrifice two motors for each unit, but it's a perfect fit and very reliable (with a cap and rectifier), and you don't have to worry about batteries anymore. The rectifier also provides a signal that the assembly has completed a rotation,…
Another idea: why not put a tiny TFT display on the motor? You can get cheap ones at aliexpress.
Standard displays are 60 Hz. You need a much higher framerate because not only do you want 60 frames a second, but you also want some number of frames per angular rotation. For 1° of angular resolution, you would need: 360°*60 Hz = 21,600 Hz display. Liquid crystals can be modulated at KHz speeds, but you're not going to find associated driving circuitry to do that. It's not easy, and there's no demand for it.
A TI DLP DMD can modulate at those high speeds, and there's readily available driving circuitry for it. However, it's a small reflective based display designed for projectors, and you would then need a light source to reflect off of it.
MicroLEDs would let you increase your pixel pitch with fast modulation frequency, but the display area is still small at the moment because of low yields. You also need a custom chip to drive the microleds at the required high framerate.