deCart is an attachment to a shopping cart that uses social pressure to make the shopping a more productive, connected experience for society as a whole.
List of Materials
Although the entire premise of the project is simple, the implementation, however, is not and requires a lot of patience and system building.
- LCD Display. For us, we used Sparkfun’s Basic 16×2 Character LCD – White on Black 5V. See https://www.sparkfun.com/products/709.
- 11 x LED lights. One to indicate selfishness (we used red), the other ten to indicate progress bar (we used yellow; colors are up to your discretion).
- Speaker circuitry and any 8-ohm speaker. Specifically, this breakout board https://www.sparkfun.com/products/11125 and amplifierhttps://www.sparkfun.com/products/11125.
- Bluetooth Modem – BlueSMIRF module from Sparkfun – https://www.sparkfun.com/products/12582.
- Materials needed to construct the box. In our case, we used simple wood.
- Arduino Mega 2560.
- 1x Piezo drum sensor.
Step by Step of our Build Process (Hardware)
Step 1: Familiarize yourself with the Circuitry!
Test each individual circuit and get a handle of the connections. For example, try turning on the LCD display, controlling the progress bar, flashing the selfish light, etc.
Step 2: Construct the Design!
See the roughDesign.DXF file. For us, we made our product by laser cutting wood.
Step 3: The Interface Components
Hot glue all the components that have slits for them! Example: the LCD display, speaker, and the LED lights. Make sure that they fit snugly in and they don’t protrude outwards.
Step 4: Wire them!
Each LED light needs to be connected in series to a 200 ohm resistor and not to mention that all their grounds need to be shared. For the LCD display and speaker, I would recommend using a protoboard. For me, I created a makeshift shield for the Arduino Mega, soldered on the speaker circuitry, and had all wires eventually lead into this board.
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