Week 3 (Outside Lab) - Experimentation & Further Study

During this meeting, the team members continued to familiarize themselves with the purchased materials, including the AC receptacle and electrical box. Parm and Le attempted to figure out how to create a custom AC outlet that is controlled by the Arduino, but generally found Internet resources confusing on the topic. The team is at present unsure of whether the custom outlet would have to connect directly to a wall outlet, and whether the Arduino can be powered by the same power supply or if it needs a wall wart of its own. This raised questions of whether the necessity for so many cords and wires would compromise our goal of a simple, clean aesthetic design.

In the meantime, Michelle figured out what modifications the aquarium pump required for the project's purposes, and Davina began to learn about controlling the Arduino through serial ports (USB) and coding a very basic GUI in Qt. A screenshot of the in-progress code and GUI—which controls the brightness of an LED—can be seen in Figure 1.

Figure 1. In-progress Qt code and GUI.

Week 3 (In Lab) - Circuitry Lessons

Figure 1. A blinking LED circuit.

The team members spent this lab familiarizing themselves with the purchased materials, primarily the breadboard starter kit. The kit includes a small breadboard, wires, various resistors, an instructive booklet, a disc with pre-written code, and other useful implements such as transistors and relays.
While Michelle experimented with the aquarium pump and other mechanical parts, Parm and Le followed some lessons from the instructive booklet, which (in order attempted) were:

1. A very simple circuit that lights up an LED when a button is pressed. 
2. An expansion of the LED circuit, with 6 LEDs that fade on and off from right to left, as pictured in Figure 1. 
3. A circuit involving the relay, which was much more complicated and only half-successful in implementation, as the lab's time was coming to an end.

The breadboard was powered by our Arduino Uno, which was connected to a computer and running the pre-written code from the disc. Davina took this time to read through that code and learn how the Arduino syntax relates to physical results. 

Week 3 (Outside Lab) - Purchasing Materials

Figure 1. Gathered project materials after shopping.

The team took a trip to Wal-Mart and Home Depot to buy the materials listed from yesterday, and was able to acquire most of what was needed. The purchased items are described below:

• AquaTech Power Head submersible aquarium pump, 170 gph, $21.52. This pump has a suction cup that allows it to stick to the side of a container, which could potentially be very convenient for the water reservoir. It has a few more features than strictly necessary for this project, but was the only pump with both an input and an output.
• Grounded electric receptacle (AC outlet), $1.57. 
• PVC electric box for wiring the outlet, $1.47.
• 20' vinyl tubing, 1/4" outer diameter, $3.11.
• 3/8" inner diameter barbed nylon tee (for splitting water flow from one input to two outputs), $2.41.

A starter breadboard kit also arrived in the mail, so the team is in a good position to get a lot of work done in lab tomorrow. Still needed are a wall wart for supplying power in the long term (the Arduino should work using a USB connection for now), and a water reservoir.