Build the Circus

This project was built as quick demonstration of Bluetooth LE support in CircuitPython in about 90 minutes. So I cut a lot of corners on the construction, using tape liberally.

Make the Front Panel

I used Microsoft PowerPoint for placing and scaling clip art and Adafruit graphics. After printing it on cardstock, I cut a hole just large enough for the NeoPixel ring by tracing around it and then using a hobby knife. Here is the PowerPoint file, and also PDF, and PNG versions, but you can be creative and make your own!

Wire the NeoPixel Ring

Next, wire alligator clips to the NeoPixel ring. Cut a red, a black, and some other color alligator clip lead in half. Strip a small amount of insulation off the ends, enough to stick through the connection holes on the NeoPixel ring. Twist the stranded ends. Put the black wire in a GND hole, the red wire in a PWR +5V hole, and the other color in the DATA INPUT hole. Bend the wires over, solder, and trim.

 

The NeoPixel ring pictured has the wires coming out the front of the ring. This was what I had on hand, but for this project, coming out the back is better.

 

Alternatively, you can solder single pin headers to the holes on the ring. Pictured is a smaller ring using this technique.

Mount the Parts

Tape the front panel to the bottom of the board, using one piece of tape on the front wrapped around to the bottom fo the board, and one on the back attaching the panel to the top of the board.

Put the NeoPixel ring into the front panel hole from the back, and tape it there.

Fasten the servo to a scrap piece of wood by putting a couple of wood screws throw its ears on one side. Then tape the scrap to the base with packing tape.

Fasten the CRICKIT to the base with hook-and-loop tape, screws, or double-sided sponge tape. I used hook-and-loop for easy removal.

Plug the servo into Servo Port 1 on the CRICKIT, with the yellow wire pointing to the outside. Attach three jumper wires to the NeoPixel screw terminals on the CRICKIT. Connect a red one to +5V, a black one to GND, and some other color to the signal pin (the arrow). Connect the alligator clips to their appropriate colors

Dress the wiring with tape for neatness.

Attach the Servo Arm

Before you attach the servo arm, you need to set the servo to 0 degrees. Your servo should have come with a variety of plastic "horns", with mounting screws and possibly small metal sleeves for the screws. Slip a horn onto the servo shaft without a screw and turn the shaft clockwise until it stops. Don't force it. There will be a little resistance, but if you're not sure, try going back and forth to feel how it moves.

Then take the rod mentioned in the parts list and tape it to the horn, so that it points through the front panel hole. Reposition the horn if necessary, and then screw it on. Adjust the length of the rod so it will clear the top of the hole when it moves up.

Now cut out a Blinka picture and attach it to the end of the rod with tape. The PowerPoint file below has several Blinka pictures in various sizes (you can adjust the sizes), or find one on the Adafruit website.

OK, you're ready to try out the program now!

This guide was first published on Jan 30, 2019. It was last updated on Jan 30, 2019. This page (Build the Circus) was last updated on Apr 14, 2019.