Week 2 (Outside Lab) - Purchase Planning

This group meeting was spent planning for a shopping trip tomorrow, since attempting to buy materials online has proven rather too confusing. The team wrote down a more concrete list of required materials (this has changed slightly since the first submission of the design proposal), and also made the decision to use an old gallon-size plastic jar as the prototype water-reservoir.
The shopping list for tomorrow is found below.

• 110-120V AC aquarium pump, submersible
• 20-25 feet of plastic tubing
• household AC outlet, box, & cover
• relay (for using the 5V DC output to power the custom 110V AC outlet; we plan to ask employees for recommendations)
• battery adapter for powering the Arduino (most likely a 9V-to-barrel-plug mechanism)

The team is also looking into several different possibilities for creating the custom 110V outlet, one of which appears to involve powering the outlet directly through a wall wart, while still allowing the Arduino to operate as a control system.

A breadboard starter kit has been ordered and will arrive on Friday. In the meantime, Parm and Davina are currently learning how basic circuits work using breadboard simulators on the Internet. These simulators also provide the capability of programming a virtual Arduino with the virtual breadboard, which promises to prove very helpful.

Figure 1. A simple circuit on a virtual breadboard.

Figure 2. A virtual Arduino running through a simulation of code.

Week 2 (Outside Lab) - Refining Design Concept (pt. 2)

Figure 1. Snippet of collaborative research organization.

Two important changes to the project were made in this meeting after more research as a group. They are listed as follows:

1. The goal is no longer to have a cross-platform control application that connects wirelessly to the PlantParent. This turned out to require another expensive piece of hardware and an incredibly steep learning curve in several areas that is beyond the 10-week scope of this project. Instead, the final prototype of PlantParent will be controlled with a computer-only GUI (still created with Qt), which will remain connected directly to the Arduino.
2. Rather than switching from 5V to 12V, the intended design is now to relay 5V DC to 120V AC. This change was made because most water pumps with the power and mechanical adaptability that we need require 110-120V AC to work (those powered by 12V DC tend to be very small and struggle to pump water twenty inches through one output, much less supply three separate outputs at distances up to three feet). 

The team hopes to make a trip out to purchase these parts of the hardware very soon, so that we can really get started on prototyping.

Week 2 (In Lab) - Refining Design Concept

This team meeting was spent getting feedback from our advisors on our design proposal and doing more necessary research as we continue to build our knowledge and skills. The following areas were pointed out and are in the process of being addressed:

• the need for more details in describing technical activities, including things like size, volume, flow rate, voltage, etc. This helped the team begin to create a more precise concept of the intended final product.
• the need for in-text citation and references. This is tied to the former point; as more specific details and numbers are added to the proposal, the more sources we will use to arrive at these decisions.

By the end of lab, the team had begun to operate in subunits of mechanical (Michelle and Le) and electrical/software (Davina and Parmpuneet). Michelle and Le looked up specific aquarium water pumps to consider using, while simultaneously assessing what kind of breadboard starter kit to order, since that will be our base for building the control system.
Davina researched about graphical user interfaces and specific methods of controlling Arduino through Qt, and Parmpuneet started familiarizing herself with the Arduino Uno rev3. Parm was able to draw up a simple schematic of a possible relay we may build, using a transistor to switch a 5V DC output to a 12V one, which can be seen in Figure 1.

Figure 1. Initial schematic for relay switch circuit including transistor.