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Stranger Things Halloween

October, 2016

We binge watched all of Stranger Things when it came out and I jokingly suggested that we should do a Stranger Things theme for Halloween. Suprisingly, Beth agreed! I spent about a month working in the evenings to recreate the inital Demogrogon living room sequence, using synchronized lights, sounds and video projection. With the help from a friend, we also recreated the scene with Barb sitting on the diving board over the pool.

I learned a lot, including the importance of testing hardware on location.

Overall Design

A Python based scene coordinator ran on a Raspberry Pi that controlled various peripherals with support for Philips Hue, Samsung Smarthub, custom GPIO attached Neopixels and network attached applications. Effects were programmed for each type of device and the scene coordinator dispatched queues for each effect over time. A Mac Mini registered as a network attached application and received queues to drive the projected animation.

The Demogorgon

The Demogorgon was built in Unity with a model that was close enough from the Unity Asset Store. I animated it to push and tear through a simulated piece of cloth to create the effect of it rippling through the front of the house. After seeing how the previous year's Halloween Spiders clearly showed the extents of the projected images, I also animated a flashlight beam shining onto the wall to illuminate the monster. This prevented the projector from illuminating the entire wall and just revealed the parts I wanted to show. Since this is a realtively quick project, I didn't know exactly where the projector would be placed. I continued my use of a PlayStation controller connected to the virtual camera which allowed me to zoom, rotate and pan the image to correct for projection distortion based on the final projector position once I had it in place.

Barb At The Pool

Barb sat on a diving board over the pool and trick-or-treaters passed by her on the way to the door. To capture the look of a steaming, warm pool on a cold night the pool was actually a fog machine lit by a animated Philips Hue Lightstrip. I worked to get a color sequence that looked like an illuminated pool.

Alphabet Wall

The alphabet wall used 26 neopixels programmed to run various effects, including spelling out messages and randomly flickering when the Demogorgon attacked. My friend recreated the wallpaper from the show and we mounted it on two sheets of plywood covering the garage door.

Unfortunately I realized only the day before Halloween that the pixel spacing was too close to match the letters. To make everything line up, I needed 13 inches between each pixel. I also knew that the signal line was sensitive to voltage drops between the pixels and the introduction of splices and extra wire could cause problems. I had a spare, untouched set of neopixels so i decided to risk spacing out the pixels. This required splicing the signal line and the power lines between each bulb.

Once done, I reconnected them to the Raspberry Pi and found that they all worked perfectly! It was time to move them out to the wall. Unfortunately some of the splices did not hold and once installed, the pixels stopped working. At this point it was the late afternoon on Halloween. I improvised and got it partially working, but sadly the wall never fully worked for Halloween. The rest of the effects worked as designed and overall it was still a success, but next year I need to plan on doing installation before Halloween day.