Engineering Design and Development Project (PLTW)
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As a high school senior, I took an engineering course called EDD in which I spend the entire year on a single group project to develop a product using SCRUM and agile project management, industry standard theories of project development that governed our organization and progress. My group's project, which had to do with solving the issue of ski theft, was well-received by the judges and the audience during the final presentation. Our design satisfied the two greatest concerns of the sample of skiers that we interviewed, which were essentially convenience and durability. Skiers are a lazy bunch with numb fingers and a certain amount of impatience (I say this as an avid skier myself), and the most significant issue with current solutions is the lack of convenience of operation. Thus, our product utilized a single button to unlock the system with security authentication obtained by a Bluetooth link to a user's cell phone. If my group had had access to funding and materials, the product would have been made of low-friction Delrin plastic (from DuPont) with Nylon side plates for increased impact resistance. It attached to skis by enclosing the bindings in a ratchet-jointed C-clamp.
The system utilized a very inexpensive and precise stepper motor for actuation of the unlocking mechanism, and it could be operated by a coded series of button pushes in the absence of a phone. It had a cable to wrap around a ski rack for extra security which was secured by a channel lock similar to a door's bolt. The circuit design was completed and fabricated on a prototype board using production components (including an AVR microcontroller, an HM11 Bluetooth module, an external clock, a buzzer, an RGB LED, a motor, a driving transistor array, and many other supporting components). The PCB was designed in Altium Circuitmaker, a free cloud-based program, and fabricated by OSH Park, a cheap Oregon based community PCB manufacturing company.
The system's mechanical design was conceived in group collaboration. I refined it and created the CAD files for the device in Autodesk Inventor, making three distinct versions as the design was fleshed out and our errors were made clear in prototyping. In the final version of the prototype, several components had to be laser cut for the increased precision and integrity offered by laser-cutting as opposed to 3D printing. The device was effective as a proof of concept for a Bluetooth-based ski lock, and it functioned as intended with a fully operational mechanism and a partially operational Bluetooth/app interface.