The encryption portion of the hardware.
The inspiration behind our novelty hack was to eliminate the chip for good. Our prototype device receives transmitted credit card data through flashes of light that represent binary, and stores the data string via photoresistor. From there, it interprets high and low voltages as 1's and 0's and seamlessly saves all of your credit cards in a single device. You can now ditch your wallet, and actually broadcast the encrypted data via an electromagnetic field that we generate through several motor drivers, so you can make purchases at any Point-of-Sales terminal. On top of that, we create an air-tight means of data transmission! The inspiration behind this invention was technology such as Swipe or Square. They encrypt magstripe data into an audio file, but there have been known ways to break this. We thought outside-the-box, and created a way to transmit this sensitive data via LIGHT instead, which is virtually unhackable because there are no scenarios where there can be interceptable packets.
How we built it
Claire Li wrote the Android application that communicates the binary light signals, and created the hardware portion of the hack that recieves the magstripe data into the device. We send the photoresistor signals into an analog input pin in an Arduino Uno, then route it to a Raspberry Pi that interprets the information. Ben Roytenberg created the hardware portion of the hack that broadcasts the data to POS-terminals for real purchases, and interpreted the stored magstripe data. He generates the electromagnetic field with this information via stepper motor driver.
Challenges we ran into
This was a very complex hack, and we ran into obstacles across every form of technology we worked with. From the first night, we realized we had to SSH headless into a Raspberry Pi and got stalled with running even the most basic scripts or checking that the photoresistor circuit was even working (it definitely wasn't, and had to be redone three or four times with help). Claire ran into issues with multi-threading and controlling the flash on an Android device to communicate the light data, and getting the photoresistor circuit to work. She had to also find a way to package the information and pass it to Ben's portion of the hardware. Ben ran into issues such as researching Track 1, and Track 2 data for credit card magstripes, and coming up with the technology to generate the electromagnetic field, and doing a lot of prototyping and testing to ensure the data is being emitted correctly.
Accomplishments that we're proud of
Throwing together the entire hack as a two-man team, and working across software and hardware, and creating a device that challenged us not only as software engineers, but also as taught us a lot about embedded systems and financial security technology.
What we learned
Where there is a will, there is a way!
What's next for LightSwipe
Adding multi-colored LED's that show live progress of transmission, and setting up a web UI that also shows transactions.