Blinkdom: Electronics, Signage, TouchOSC, Locks and Windows

Meet Blinkdom in 3D

San Antonio Mini Maker Faire, Mar 26, 2016 11am-4pm at the SA Public Library. Please come say hello and help remind us to keep going.

Sanantonio mmf2016

Getting Ready for SA Maker Faire

The clock is ticking down but we are still making progress for showtime this weekend. Here what’s happening behind the scenes.

Bottle Locks

With the LEDs functioning, it is time to button up the third panel. One task is to cut the PVC “bottle locks”. Using a setup block from WoodPecker’s, we set the bandsaw blade to cut pieces 0.625in wide.

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The pieces are then cut into a “C” shape to clamp around the neck of the bottle.

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These PVC locks hold the bottle in place by wedging between the face of the grid panel and the ring on the neck of the bottle. We need 200 per panel.

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Adafruit Trick

We buy LED strips from Adafruit, recently to replace one in a PixelStripInvader. While installing the new strip we checked out their LED-related pages.

After running Blinkdom for a few hours at full power, we noticed some erratic pixels in the last strand. Based on what were learned about LED strips from Adafruit, we tried one of their tricks on a 12mm RGBLED. A known issue is the controller chip doesn’t seat correctly in the LED. We went to the first pixel misbehaving in the strand and gently squeezed the chip with pliers. Problem solved! It and the six or seven downstream now work.

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More Pi Please

With all the pixels locked in place and working, it was time for another upgrade. The Raspberry Pi 3 Model B was released which we ordered as fast as we could. One of the vendors warehouses in Fort Worth so we hoped we could get one shipped before the Maker Faire. After a few days without a shipping notice, we broke down can contacted the vendor. They expected to ship by March 26. Sadly, we moved on to other tasks on the list.

Then unexpectedly a box arrived with three Pi 3s!

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After some quick ‘dd’ magic, we cloned the original Pi v2, upgraded it to Raspbian Jessie and Blinkdom’s rendering speed is improved. We were also able to install the USB sound card so we’re sound-active too.

TouchOSC Updates

Blinkdom (through PixelController) can respond to OSC commands to set brightness, load presets, change colorsets, etc. Using TouchOSC, we created custom interfaces to control Blinkdom on an iPad. This time around we added a page to play any of the 144 presets. The ones with green buttons are our favorites. We’ll have an iPad on a stand to change Blinkdom during the Faire using this screen. We made another interface using PureData in PdParty that runs natively on iOS.

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Power Terminals

Having raw wires stripped and wrapped around the screw terminals on the power supply just don’t look finished. To clean that up we got some Ring Terminal #8 with a heat shrink sleeve. These were used to group three positive and negative wires for injecting power in the LED strands.

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The screw goes through the Ring Terminals into the power supply terminals for a secure fit.

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Continuing clean up, we needed a way to display the Blinkdom electronics nicely. Normally all the cabling and devices are tucked into the footer boxes, out of sight. For a Maker Faire, we want to show how everything is done. After some quick sketches on index cards, we created a simple solution. To expose the components, we want to mount them on a vertical panel off the floor. We can cut a sign into the opposite face that we can place behind Blinkdom to prevent people from walking behind it.

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We have the robot cut two of them so we have a sign to put at the front of the booth too.

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On the back of the sign we have plenty of room to mount (from top to bottom) the wireless access point, network switch, Raspberry Pi, PixelPusher, and the power supply. Worst case, somebody steps up and yanks all the cables out.

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Footer Box Window
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