I made a bunch of progress this week. Most of my work was put into integrating the thermal sensor into the final design, which ended up being much more painful than anticipated. The one thermal sensor we had was broken and I unfortunately didn’t have any good way of verifying that the sensor worked until the rest of them arrived on Wednesday, so I spent a lot of time early in the week writing and running different segments of code in an attempt to debug things. Fortunately, after getting new thermal sensors, I was able to get the system running on an Arduino Uno pretty quickly, and then after a bit more work I was able to transfer everything over to the ESP system, which is now running a functional occupancy detecting algorithm using both sensors! The final hardware design can be seen below (although the design will be on a smaller breadboard for the final demo).
As a very important note to future teams looking to do something similar, we made the design decision early on to use an ESP8266 dev board with both a processor and a wi-fi chip built in as opposed to using an Arduino with an external wi-fi chip to reduce the amount of hardware, since the ESP can still compile Arduino code. Although this was a good idea in theory, it made things much harder for both myself and Jake, as the Arduino is much more user-friendly than the ESP for software development and has much more existing uses and documentation to learn from. If we were to restart this, we would definitely develop things on an Arduino instead.
After finishing all that up, I then assembled the rest of the hardware nodes to work with Jake to kick off battery testing. While we shouldn’t have definitive results until tomorrow (fingers crossed, because it means the batteries will have lasted at least a day), those results will be in on time for the final presentation. I am also planning on working with Jake tomorrow on unit power testing to further verify that our system is within our power consumption use case requirement. We will be measuring power draw out of different components while running different sections and libraries of code in a further attempt to optimize power, and preliminary results for those should also be done by the final presentation. If all ends well, I will spend the rest of next week hearing other presentations and preparing for our demo. If not, which is probably the more likely scenario, I have a risk mitigation plan which I will detail in the team status report. Currently I am pretty well on schedule to finish everything out, and I am hopeful that will stay the same for the rest of the semester!