This project shows how to control a washing machine in a home automation environment using MQTT.
The LEDs of the washing machine are read using photoresistors attached to digital pins of the WeMos. Using a 10kOhm resistor a voltage divider is formed. The 10kOhm pulls to ground and the photoresistor pulls to Vcc. Since the resistance in the dark is high the pull down dominates. Illuminated, the photoresistor pulls the level at the pin over the high threshold. This way the digital pin can read if the LED underneath the photoresistor is lit.
A MG90s servo motor is used to push a button. The servo signal is generated using PWM at 50Hz with a valid duty cycle between 5 to 10%.
As MQTT Broker a Raspberry Pi with Mosquitto is used. See here.
Code & 3D Models
For the firmware Mongoose OS is used. The code is Java Script run on the default esp8266 image. Models are available as blender files and stl. All files can be found here:
https://github.com/bitluni/SmartWashingMachine
Mongoose OS can be downloaded here:
https://mongoose-os.com/software.html
Apps
The MQTT apps used have been MQTT Dash and MQTT Snooper for android devices. (Sorry, have no Apple devices)
Node-RED Flow
This is the current Node-RED flow as shown in How to Node-RED!
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Parts
WeMos microcontroller:
http://s.click.aliexpress.com/e/jUfAmUF
http://ebay.to/2skrCE1
http://amzn.to/2saaoKL
Photoresistors:
http://s.click.aliexpress.com/e/IUJYVrN
Photoresistor modules:
http://s.click.aliexpress.com/e/vzrvN3j
MG 90s:
http://s.click.aliexpress.com/e/7eAAQz7
…more links to come
These links support my work at no additional cost for you. They are just a reference so you can find the right parts.