Nest ePaper Signage

Project Status

All signs are installed and fully functional as of October 2020.

Project Overview

I wanted a display of calendar events on our wall, and started this project to accomplish this. In the end it resulted in a system of 4 types of ePaper signs around the house displaying various pieces of information.

System Requirements

• Off the shelf hardware available
  • I wanted to get the system completed and in use quickly, rather than having to iterate on a hardware design before I could even start on the software side.
• Wireless data transmission
  • I didn't want to have to run new cables around the house to drive data to the signs, and we don't have Ethernet or any other data running around the house currently.
• Able to run on battery power for 1 month or more at a time
  • Some of the signs are in places where running power to them would be a problem.
  • Even for the signs that are near power, things look nicer without extra wires, and using up outlets isn't ideal.

Hardware Evaluated

The battery requirement pretty much limited my options to ePaper, as LCD displays generally required being plugged in due to the power requirements over weeks or months. I looked at several ePaper-based options before settling on one.

• Generic Aliexpress ePaper Shelf Price Displays
  • Pros
    • Inexpensive
  • Cons
    • No open protocol or API in most cases, just software to push new prices out from an Excel spreadsheet or similar.
    • Tend to only be available in very small sizes
    • Air protocol tends to be something custom, not Zigbee or WiFi or anything
• Joan meeting room displays
  • Pros
    • 3 month battery life
    • Touchscreen device
    • WiFi communications
  • Cons
    • Display starts at $549 which is more than I was looking to spend on one display.
    • Monthly plan required to display custom content, which starts at $21 per month per display.
• Advantech ePaper Display Devices
  • Pros
    • Nice looking displays in a variety of sizes
    • Buttons on several of the displays
    • 802.15.4 communications
  • Cons
    • Larger sizes of display are "Coming Soon"
    • Protocol is proprietary and requires the Advantech hub device which starts at $720
• WaveShare NFC Displays
  • Pros
    • No battery required, powered by NFC from the device performing an update
  • Cons
    • Only updates when an NFC device is held up to the unit, can't update on-demand.
• SyncSign ePaper Displays
  • Pros
    • Least expensive displays of any of the options, especially for smaller sizes ($35 for 2.9", $99 for 4.2", $299 for 7.5")
    • Hub is also inexpensive ($70) and uses Zigbee for hub to display communications
    • Open API to draw custom content on the displays
    • Battery life averaging 1 year with signs set to poll every 10 seconds and getting 7 updates a day pushed
    • 4.2" sign has 4 buttons on it
    • 2.9" and 7.5" displays are three-colour (black/white/red now and black/white/yellow coming soon)
    • Hub also supports connecting Zigbee sensors to monitor temperature, humidity, light, occupancy, etc.
  • Cons
    • Relatively unknown company, unsure if they'll be around long-term

Project Details

• Calendar - A medium square sign that displays the events coming up on the current day, or the next day if it's later in the day.
• Dog Food - A small sign in the kitchen that displays which food and medication each dog needs next.
• Alert - A small sign on the fridge that displays any alerts from the home automation system, or the current date if no alerts exist at present.
• Weather - A small sign that displays the current weather type, temperature, and humidity, and what weather is coming up in the near future.

Images

• Sign-Dogfood.jpg

  Dog Food Sign

• Sign-Calendar.jpg

  Calendar Sign

• Sign-Weather.jpg

  Weather Sign

• Sign-Alert-Normal.jpg

  Alert Sign - Normal condition

• Sign-Alert-Abnormal.jpg

  Alert Sign - Abnormal condition