Desktop SpokePOV

by laxap in Circuits > LEDs

15274 Views, 24 Favorites, 0 Comments

Desktop SpokePOV

pov-summary.jpg
Have fun with a SpokePOV, also without a bike, and on your desktop!

What is a SpokePOV? See http://www.ladyada.net/make/spokepov/ .

Instead of mounting it on a bike, we'll use an aluminium bar and a motor.

And because it's soon Xmas time, show some nice season images.

(And to justify my entering into the "Light Up the Night! Contest": while I admit that this can be cumbersome to carry with you, I must say that desks too have a right to be more visible at night)

Get and Build a Spoke POV

spokepov.jpg
Get SpokePOV parts:
If you opt for a Ladyada one, get the parts there: www.adafruit.com/index.php :

- 2 x SpokePOV Kit
- 1 x magnet
- 1 x dongle kit
- or -
- 1 x  Triple SpokePOV Kit (including 3 PCBs, all components, 1 dongle, 2 Magnets)
 
You will also need:
- 1 Lego motor
- Lego gears, a couple of Lego bricks
- 1 aluminium bar
- 1 piece of (scrap) wood
- some screws and bolts, small metal plates, zip ties or tape
- either a Lego battery pack, or a lab power supply, wire and plugs
 
Build the SpokePOV (two PCBs needed):
Follow Adafruit's instructions to Build two PCBs. DO NOT SOLDER YET the Hall effect sensors!

Mount PCBS on Aluminium Bar, and Position the Hall Effect Sensor

IMG_1653.JPG
IMG_1653b.JPG
IMG_1654.JPG
Cut the aluminium bar to size, drill it, and mount the two PCBs as shown.

Check for shorts, if needed insulate the aluminium bar with tape.

Mount the central gear. The gear diameter does not matter: it will serve as hub.

Position the Hall effect sensors near to the center. To determine the exact distance see step 5.


Gear and Motor

IMG_1656.JPG
IMG_1658.JPG
IMG_1657.JPG
IMG_1655.JPG
Mount the gear on the Lego motor.

Mount the motor on the bricks, and tighten to the wood using screws, bolts and metal plates.

The L-shaped plate is here to hold the magnet.

Finally you should tighten the motor's body to the wood, using zip ties or tape.

Add a Power Supply

IMG_1658b.JPG
IMG_1698.JPG
Tighten the Lego battery pack to the wood, and connect it to the motor.

Alternatively, if you have a lab voltage supply, it will allow you to get a progressive acceleration.

Tighten the wood to your desk.

Design and Flash Some Images

Screenshot.png
Now this is standard SpokePOV setup and operations.
  • Design some monochrome images, process and convert them (to BMP format) using your favourite image editor, as told on www.ladyada.net/make/spokepov/software.html.
  • Setup your SpokePOV and flash the wanted bitmaps using the SpokePOV software.

Align Magnet and Hall Effect Sensor

20-sma.jpg
Now mount the aluminium bar on the axis.

The magnet and Hall effect sensors should come close to each other at each half rotation, but not touch. Nearest distance approx 5mm.

Ready to Go

IMG_1698.JPG

Try It!

IMG_1701.JPG
IMG_1699.JPG
IMG_1700.JPG
IMG_1703.JPG
IMG_1855.JPG
IMG_1858.JPG
Now have fun.

You can take photos (using a tripod) and make greeting cards (one instructable on this later).

Note: the front LEDs row is not exactly on the radius, and is hence causing some image distortion near the center. To avoid this, find a way (in step 2) to align the front LEDs to the middle of the aluminium bar.