YNC_Laundry

Table of Contents

Project Overview
SOFTWARE
Frontend
Backend
Flask_App
HARDWARE

Project Overview

Hello! Welcome to the Yale-NUS College Laundry Codebase. This readme should be read alongside the writeup over at: https://chuayunda.com/2020/02/25/yale-nus-smart-laundry/

The folders: Deployed and Website are both live on the systems at Cendana.

Original Repository by Shardul Saptoka Yale-NUS College '20, and heavily edited by Yun Da, Yale-NUS College '22

Software

Frontend

If you're interested in frontend

1. For what's being displayed on the webpage using the HTML: You'll want to head over to ~/website/app/templates In there, you'll find the 3 html files which will be loaded when you head over to the webpage at laundry.chuayunda.com
2. For the HTML code to get the status data from the flask web app: edit the HTML's javascript, and /website/app/routes.py. The flask app's home folder is in ~/website/app

Backend

If you're interested in how data gets sent from the laundry room to the web server:

1. The raspberry pi code can be accessed at: ~/Deployed/pi_central.py
2. Arduino code is found at: ~/Deployed/10_Feb_2020.ino

Flask Python web app (Which interfaces with Gunicorn and NGINX for load balancer)

1. We used to use SQLalchemy but I found it too clunky with flask. We're now using a json to store the status data, and send them around the app. ~/website/app/status_db.json
2. With regard to the weekly forecasting features, the script doing that can be accessed at: ~/website/app/upload_gsheets.py. I intend to run it with a cron job and just read from the ~/website/app/status_db.json file and update a gsheet automatically to keep a proper log of all the events that happened, where it can be exported to R or some other program for further processing.

Hardware

Arduino pro mini 8MHz https://www.aliexpress.com/item/32672852945.html?spm=a2g0s.9042311.0.0.5a504c4dVc4d6i AT-09 BLE module https://www.aliexpress.com/item/32820135156.html?spm=a2g0s.9042311.0.0.5a504c4dVc4d6i Raspberry pi 4 2GB

Instructions:

1. Upon receiving BLE chip, download Arduino IDE, plug in using USB to TTL https://www.aliexpress.com/item/32831329095.html?spm=a2g0s.9042311.0.0.5a504c4dVc4d6i from Mac directly to the BLE chip and do the following through the serial monitor of the Arduino IDE (Magnifying glass with a + symbol on the top right hand corner of the IDE):

AT Commands to run on the AT+09 Change transmission power (0 [-23] is lowest, 3 [+6dB] is highest): AT+POWE3 Change name: AT+NAMEYNC_Laundry_3-6 Check MAC Addr (This address will be used on the python script to check for its sensor readings): AT+LADDR Check Peripheral (0 is peripheral): AT+ROLE

Light levels for arduino: 735 for washer 6 and 5, not sure yet for washer 3

Problems:

1. Cannot send numerical lightVal over BLE to Raspberry Pi using UTF-8
2. The Bluepy python module runnin gon the Raspberry Pi 4 gets into a bad state quite quickly, so I used crontab to restart the script every 10 minutes.
3. Washer 3 gives out error instead of AVAILABLE/UNAVAILABLE often enough.