An Electrical Bridge
Things were coming together. The physical component of the desk was prototyped. I had network access. Now I needed to bridge the two.
In order to get enough power to run, Bertha, the vibration motor, needs 24v. The Arduino runs 5v. In this case, the Arduino acts as a gate keeper–when it gets a specific input (an SMS) it sends a little current to a transistor circuit which is the gate. The transistor does the job of electrically connecting the motor and its 24v power supply.
This little circuit board was designed to fit right onto the GSM shield. This would help keep the various network-related components in a relatively contained package–something that would be easier to mount to the desk.