Twitchboard — Prop Controller with Triggered and Background Activation

 Sometimes you just need a -little- chaos. 

So you’ve built or bought this amazing prop. You don’t want it on continuously, because that gets boring. You want it occasionally and unexpectedly going off in the background, and then you want it to really go off when triggered by an unsuspecting victim…errr, guest. You need a Twitchboard.

The new Twitchboard is the little sibling to the Twitch-n-howl board. Coming in at half the size, half the price, the Twitchboard is a trigger-able 12V prop controller that also provides an adjustable random background rate of activation.

Triggers

Just like the Twitch-n-Howl board, the Twitch board can be triggered by a wide variety of sensors and buttons. Anything that runs on 5V and returns a "HIGH" signal put the board in "ON" mode where it gives more frequent activation. PIR sensors work great, but even simple buttons can add some fun interaction.

Random Background Rate

The (pseudo)random background event rate for the Twitchboard is based on a Poisson process. If you’re interested in traveling down that particular rabbit hole, click here to read my blog post on the topic. Otherwise, it’s sufficient to know that this results in a background frequency of events that feels less predictable. Events occur both earlier and later than your brain expects. The average frequency of these events is adjusted by the potentiometer and ranges from every 10 seconds to every 2 minutes. If you need something different, just let us know, and we'll adjust the code before we send it to you. 

Output

The Twitchboard gives a 12V output signal. This can be used to activate lights, motors, and relays. The default duration is 200msec which works well for flashes of light and brief motor signals like door lock actuators or vibration motors. If you need a longer (or shorter) duration of signal for a motor driven prop such as a leering skeleton or cauldron creep, just let us know, and it can be set for whatever you like. If you want to run a smaller motor (6V for example) or a 12v motor more slowly, the PWM signal can be adjusted when we program the chip. Unfortunately, the Twitchboard does not have an output for sound. If you need audio, check out the Twitch-n-Howl board.

Open Source

The Twitchboard is open source (code and schematics) and fully end user modifiable. The code for the board runs on an ATTINY85. Jekyll-Labs loads the initial code, but this chip can be further programmed using most standard Arduino commands in the Arduino IDE. Sparkfun has a great tutorial on the subject. Take what we've created and make it your own.