***NOTE: Link to GitHub containing results is at bottom of page***
Results
After working through our process and technical methodology, we ended up with a number of outputs for our project at the end of the semester. These included both a prototype of our snake implants that had basic functionalities and a custom PCB that could serve as a miniaturized version of the prototype. However, due to a misinterpretation of our microcontroller data sheet, we were unable to program our PCB.
Trade-Offs
Battery vs. Number of GPS Acquisitions
Due to the constraint on the size of our battery, we had to make a trade off between the battery life and the frequency of GPS acquisitions each day. Due to the high power draw of the GPS, the number of acquisitions has to be 1/2 per day in order to make the battery last 8 months.
Size constraint vs. Cost
Due to the size constraint, we had to use small, 3mil traces (3 millionths of an inch), along with SMT components. This drove up the price of our project and complicated matters from a hardware perspective
Moving Forward
Future work on this project can be broken down into three main categories:
- Miniaturize board further to fit within 10x40mm size constraint. This can be done by rearranging components in EAGLE, our design software.
- Purchase an SWD programmer/debugger to program and debug the board. Since we were unable to use the embedded programmer/debugger in the SAM Xplained Pro, future groups would have to purchase a programmer/debugger, and would have to reconfigure the PCB slightly to open another line of UART communication for debugging.
- Test the GPS and LoRa communication, and compare the results to those of the prototype. Develop a front end to display the resulting data.