Inspiration: We were thinking about ways to nurture long distance relationships with family, friends and partners by letting them know you are thinking about them which eventually would encourage you to contact them and stay connected.
What it does: There are two sister picture frames in two different locations and once you touch one frame, the other picture will instantaneously light up and your loved ones will know that you are thinking about them. This works in the other way as well.
How we built it: We placed one Arduino in each etched frame, and configured the HC-05 Arduino Wireless Bluetooth Receiver RF Transceiver Module for each Arduino between two frames, such that they can communicate wirelessly. This can easily be replaced with Wifi communication, so that frames can be placed longer distances apart. The aluminum frame acts a capacitor in a RC circuit, and once a person touches the frame, their capacitance adds in parallel and increasing the overall capacitance. Therefore, the RC time constant of the circuit changes thus enabling us to detect changes in frequency of a wave. It works such that the master Arduino sends data to a slave Arduino and vice versa. The Arduino is therefore capable of sending and receiving signals, so when one frame is touched, its "sister" frame is lit up.
Challenges we ran into: Bluetooth communication between the Arduinos
Accomplishments that we're proud of: Bluetooth communication between Arduinos, capacitive touch sensing, reverse engineering Adafruit's ELwire by passing an inbuilt switch to override initial functions
What we learned: Bluetooth communication
What's next for Keep In Touch: Replacing Bluetooth communication with Wifi, individually personalized etchings, frame that plays music additionally