Servo - September 2015

At first glimpse, electronic “bits” that snap together under the power of magnets might not seem suitable for enduring the rigorous candy-grabbing armies that invade a house during All Hallows’ Eve. However, with some careful planning (see Figure 1) and robust building techniques, you can assemble these three treats in one evening. They’re perfect for adding some excitement to your candy bowl.

Boo2U

It’s time to add some twitch to your tricks. In this project, we’re going to animate a simple hand puppet. The puppet will come to “life” when children come near it. This effect is a great demonstration of four very basic littleBits modules.

First of all, we need the ever-present power module (p1). This little beauty gives life to all of our littleBits creations. Just plug a 9V battery into the barrel jack found on the p1 module, and you have a sweet portable power supply — complete with an ON/OFF switch.

Once we’re juiced with the power module, we add a sound trigger (i20) module. This is an input module that is color-coded pink (or fuchsia, if you prefer). The sound trigger works by “listening” to sound levels which then transmits an ON signal to other connected modules when it “hears” something. The sensitivity of this module’s hearing is controlled by a small trimmer potentiometer (pot). When the sound trigger hears a group of children speaking nearby, it triggers our third module: timeout (i17). This is another input module. Rather than listening, this module is a “thinker.” The timeout module likes to think about turning ON and turning OFF during a specific time interval.

Another trimmer pot controls the duration of this module’s thinking period. A separate toggle switch sets whether the timeout is ON then OFF, or OFF then ON. Regardless of the switch’s state, its thinking period will determine how long our fourth — and final — module remains active.

Our hand puppet is controlled by a small DC motor

We've all learned about littleBits ( littlebits.cc) — the magnetically-attractive building modules — from past issues of SERVO Magazine (see November 2014, December 2014, February 2015, and June 2015). Now, it's time to put them to real work — for Halloween 2015!