Weekly Status Reports

This week, I spent most of my time finishing up the project overall. Dina, Sam, and I worked together to connect the Arduino from Sam’s circuit to the RPi. I wrote the code on the RPi to read the ID card number from the serial monitor on the Arduino and then send the request with the ID number and the time to our web app server. We were able to successfully scan several different IDs on the RFID circuit and keep track of the entry and exit times on the web server backend. I also set up the backend to send both the live and predicted wait times to the frontend to be displayed on the web page.

My progress is currently on schedule. Next week, I hope to wrap everything up by finishing up the poster, preparing for the final demo, and writing the final report. I will also make any necessary final changes to the project overall.

This week, I spent a lot of time working on our final presentation as well as adding some minor changes to the web application backend. For our presentation, I help set up the initial outline, worked on the complete solution slides, added to the design trade-offs slide, and added tests related to my portion of the project to the testing, verification, and validation slides. Additionally, I performed some tests on our RPi to web server connection by timing how long it took for a scan and its data to be sent to the web server backend. This time was always under 2 seconds (which was our goal), and the average time was 0.96 seconds. In addition to the presentation, I was also able to set up our web application to be encrypted with SSL. This required getting a domain name and obtaining the certificate so that our traffic could always be rerouted to https. By visiting https://waitr.link, you can view our web app running encrypted through our EC2 instance! I also added some logic to have both the live wait time to be viewed alongside the predicted wait time on the web app frontend.

My progress is currently on schedule. Next week, I hope to help out with our final poster as well as finish getting the Arduino and RPi connected so that our project solution can finally be complete. I also want to make sure that there is nothing else needed on the web app backend before the final demo.

This week, Dina and I were able to successfully set up the second RPi for our system. We need two since we will have two scanners, so we need one RPi each in order to connect back to our web application. After the long setup process (since our RPi Zero W is pretty slow), I was able to add in logic in our software backend that handles a second scan of the same ID number. Now, when someone scans their ID on either of the scanners (since our web app can’t tell the difference), our backend checks if the ID number is a part of the Entry model table. If it is, then the entry time and exit time are added to the WaitTime model table and the old Entry object is deleted. If not, then the ID number and entry time are added to the Entry model table. In addition, I migrated our database backend to SQL instead of SQLite because this will better handle our data as well as concurrency issues of multiple people using the web app at once. Finally, I also added logic to use a live wait time at the top of the website if it is available within two minutes of the current time. Otherwise, the predicted value from the ML neural network will be used. A code snippet of this logic is shown below.

# use live wait time, otherwise use prediction
if (WaitTime.objects.filter(id=1).exists() and (datetime.now(utc) - WaitTime.objects.latest('exit').exit) <= timedelta(minutes=2)):
wait = WaitTime.objects.latest('exit')
wait_time = int((wait.exit - wait.entry) / timedelta(minutes=1))
else:
wait_time = ml.predict([datetime.now(eastern)]).pop(0)

My progress is currently on schedule. Next week, I hope to get our web application encrypted with SSL so it is more secure. I also hope to finalize getting Sam’s circuit connected to the rest of our system so we can have a final working product with all of the components connected!