Flik: Advancing Presentations
Background
This was my very first electronics project! I worked on it with Jayden Lee in Introduction to Electrical and Systems Engineering. Flik aimed to give users a method for “Advancing Presentations with a Flik of Your Wrist.” That is, it’s a new way to control powerpoint presentations.
The Electronics
This project contained two modules: the user module and the computer module. The user module consisted of an accelerometer, an Arduino Uno and an HC-05 Bluetooth Module. This module acted as the master and communicated with the computer module over Bluetooth. The computer module also had an HC-05 Bluetooth Module, but was built with an Arduino Leonardo as it can interface with the keyboard to “press next.”
We used the accelerometer to determine the threshold for advancing a slide. However, we had two problems: one flick was advancing multiple slides and random noise would also advance slides. A moving average filter was used to solve the second problem, ensuring only a series of values crossing the threshold would be considered a flick. After a flick was detected, the average had to settle below another threshold before another flick could be registered, solving the first problem.
The user module also had a pressure sensor by the thumb that shines a laser diode when pressed, allowing Flik to be used as a laser pointer. Using pulse width modulation, the laser varied its brightness depending on how hard the user pressed on the sensor.
Mechanical Considerations
The Arduino Uno was quite large, so the module was broken into two. The accelerometer, laser diode, and pressure sensor were soldered onto a perf board which was then sewed into a glove the user wears. Wires ran from the glove to an enclosure housing the rest of the components.
See it all in action in this short clip from demo day!