This week, I worked on connecting the receiver iPhone to the Raspberry Pi to begin transferring UWB position data to the cart’s control system. Unfortunately, I discovered that the Raspberry Pi 5 we borrowed from the ECE inventory has a broken SD card holder, which prevents it from booting or running any code. It had old solder on the pins, which likely means that others have also previously tried to fix it with no success. I immediately ordered a replacement that should arrive next week (Amazon Prime). In the meantime, I decided to make more progress with the software side. I wrote the Flask server code that will run on the Raspberry Pi to handle incoming data from the receiver iPhone. Although the code has not been tested yet due to the hardware issue, it is fully written and ready for deployment (and testing) once the new Pi arrives.
I also spent some time researching the trade-offs between using Bluetooth and HTTP as the communication method between the receiver iPhone and the Raspberry Pi. I found that HTTP over Wi-Fi has higher data throughput and stability for streaming continuous position updates, while Bluetooth has lower power consumption and a simpler pairing method, as it does not rely on a Wi-Fi connection. However, Bluetooth has limited bandwidth and higher latency, which makes it less reliable for real-time data updates. Based on this, I decided that using HTTP over Wi-Fi is ultimately the more practical choice for our project at this stage.
Overall, I remain behind compared to the Gantt chart because the broken Raspberry Pi delayed my progress. Next week, once the new Raspberry Pi arrives, I plan to set up the Flask server, test end-to-end communication between the iPhone and Raspberry Pi, and look into how we can translate those coordinates into motion controls without obstacle avoidance for a preliminary prototype. My goal is to catch up on lost time and have the full UWB-to-cart communication working for the interim demo.