book collections email follower instructable user

Harness the colors of the rainbow with the Skittle Pixel8r. Learn how to construct a machine that will create any image using Skittles as pixels. The machine is capable of creating a Skittle pixel image that is up to 785x610mm (31x24in) using eight Skittle colors (hence the name Pixel-"8"-r).

Eight Skittle dispensers (one for each color of Skittle) are placed at the top of the machine. The Arduino commands the dispenser containing the desired color to dispense one Skittle. Once dispensed the Arduino commands the linear axis to move the funnel to the correct bin. While the linear axis is moving, the Skittle falls through the funnel system. After the linear axis stops moving, the Skittle falls into the bin. This process repeats 2760 times until the image is complete.

It was supposed to be a weekend project but ended up taking a month to design and build. Skittles are surprising challenging to work with: they can roll on all sides but are not spheres, when dropped they naturally settle with the larger diameter in the horizontal plane, and the raspberry ones are irresistibly tasty.

I have uploaded a .step solid model file of the machine (see attached file). When I don't provide good descriptions of dimensions and assembly, open this .step file in your favorite 3D CAD program to find the information you need.

Tools:

  • Table saw (1/8" wide blade)
  • Jig saw
  • Miter saw
  • Hack saw
  • Laser cutter with at least 400x300mm (16x12in) bed size
  • Electric drill
  • Drill bit set
  • Wire cutter
  • Wire stripper
  • Small Phillips screw driver
  • Soldering iron
  • Utility knife
  • Tape measure

Electronic components:

  • Qty 1 – Arduino Mega 2560
  • Qty 1 – 5V power supply
  • Qty 1 – 12V power supply (to power stepper motor and Arduino Mega 2560)
  • Qty 9 – microswitches
  • Qty 8 – 180 degree, metal gear, 5VDC servo motors
  • Qty 1 – Nema 17 stepper motor (64 oz-in or greater)
  • Qty 1 – microstep stepper motor driver
  • Qty 1 – 85x54x9mm bread board
  • Qty 1 – Dupont wire 2.54mm pitch connector kit (male crimp pins, 1x1 pin female housing, 1x2 pin female housing, etc.)
  • Qty 1 – USB type B to USB type A cable (to connect Arduino Mega 2560 to computer)
  • Qty 1 – 22 AWG, 4 conductor, ribbon cable, 20m

Fasteners:

  • Qty 200 – 4” cable tie
  • Qty 1 – 4oz. bottle of wood glue
  • Qty 8 – ¼-20 hex head bolt, 0.75in long
  • Qty 8 – ¼-20 hex nut
  • Qty 8 – lock washer for ¼-20 bolt
  • Qty 10 – 1.5in long wood screw
  • Qty 20 – 2.5in long wood screw
  • Qty 2 – M5x30mm bolt
  • Qty 6 – M5 hex nut
  • Qty 6 – M5 lock washer
  • Qty 2 – M5 threaded rod, 100mm long
  • Qty 4 – M4x18mm bolt
  • Qty 8 – M4 hex nut
  • Qty 4 – M4 lock washer
  • Qty 4 – M3x8mm bolt
  • Qty 1 – M3x16mm bolt
  • Qty 1 – M3 hex nut
  • Qty 5 – M3 lock washer

Materials:

  • Qty 8 – 16x12x0.175in Baltic birch plywood
  • Qty 47–0.75x24x0.175in Baltic birch plywood
  • Qty 1 – 15x39x0.75in plywood
  • Qty 1 – 24x36x0.75in plywood
  • Qty 3 – 2x4in lumber, 96in long
  • Qty 1 – 24x36x0.175in glass sheet
  • Qty 1 – 1.5x48x0.175 aluminum plate
  • Qty 1 – large equipment funnel
  • Qty 1 – medium automotive funnel
  • Qty 2 – small automotive funnel
  • Qty 1 – 0.75in OD, 0.625 ID, vinyl tubing, 3ft long
  • Qty 4 – 4x13x6mm v-bearing, 4mm ID
  • Qty 1 – 3m of GT2 timing belt, 6mm width
  • Qty 1 – 20 tooth, GT2 timing belt pulley, 5mm bore
  • Qty 1 – 20 tooth, GT2 timing belt idler pullley, 3mm bore
  • Qty 2 – grey spray paint, 12oz can
  • Qty 8 – medium size sealable containers (one for each skittle color)
  • Qty 2760 – Skittles (estimate 25 skittles and equal number of colors per ounce)
  • Qty 1 pkg – 1/8" heat shrink
  • Qty 1 pkg – solder for electronics

Step 1: Construct the Skittle Dispensers

The most difficult challenge of this project was designing a cheap device that can dispense Skittles one-by-one from a pile of Skittles. After a couple of iterations I settled on the following design that can be laser cut from 1/8” Baltic birch plywood and operated using a 180 degree, metal gear servo and limit switch. It is important that a metal gear servo be used; the gears of a plastic gear servo are likely to strip for this application. One dispenser is required for each Skittle color. Laser cut the .dxf file (formatted in millimeters) out of a 16x12x0.175in sheet of Baltic birch plywood. Quantity of 8 are needed. Twelve zip ties are required to assemble each dispenser. Use the screws supplied with the servo to fasten the circular plates to the servo horn. Solder 900mm of 2 conductor, 22 AWG wire to the Common and NO (normally open) terminals of the micro-switch. Terminate the other end of the 22 AWG wires with 1x1 pin male Dupont connectors. Use the attached "servo_zero.ino" arduino script to orient the horn/hole plate on the servo at the correct position (see images for details). The .gif shows the correct disk travel when the servo sweeps from position 0 to position 180.

Follow the assembly sequence shown in the pictures.

Rehaan336 hours ago
Might be interesting to include a skittle colour sorting machine which would greatly improve the efficiency of sorting the skittles with little human intervention. Would definitely be a time saver.
Now you just need to make a candy sorting machine :)
Well, but there are a few problems. His explanations are May
This is insane! Awesome! Shouldn't you be working on the mission to Mars or world peace? I have no more words......
Dannlh2 days ago
Very cool! Needs a de-skittl8r at the bottom to erase and redraw automatically. Hmmm video at 5 minutes per frame?
offseidjr2 days ago
Looks complicated but well worth the time!
I'm thinking 'Skittles abacus', except the wear might affect results.
Also, are the brown ones chocolate? ..
JohnO3 (author)  paxallen10672 days ago
Writing the code to make it into an abacus would be fun. Incidentally, purple (i.e. grape) Skittles actually look more brown than purple in some light conditions.
FilipW2 days ago
One neat improvement would be to integrate the color sorting into the machine. Then only one hopper would be needed, and the software puts the Skittle in an appropriate tube depending on its color. Skittles with a color that isn't needed anywhere at the moment can be put in a tube or bucket at the end of the rig so they can be manually recycled in the hopper.
This is fantastic! Really cool design and I absolutely love the ingenuity. Made me think of Wintergatan's marble machine - https://www.youtube.com/watch?v=IvUU8joBb1Q
Good luck with the contest and once again excellent work.
zakbobdop7 days ago
This made me say "wow", great job :D
FernMakes8 days ago
Wow, this is awesome!
Alex in NZ8 days ago
This is amazing! Thank you for showing it and good luck for the competition :-)