Seems like about ever 3 - 4 months, my daughter or wife call saying they left the house for a walk and forgot their keys and the keypad on the garage door won't work. It's either user error, which the pad isn't very intuitive, or the battery is dead on it. And it usually occurs when I'm out of town or at work.
So I've been playing around with some new devices that utilize the very affordable ESP8266 Wifi chip, the Nodemcu (http://www.amazon.com/Wireless-devel.../dp/B01ACJIAPU). The device can be programmed using it's native language, Lua (http://nodemcu.com/index_en.html), or using the Arduino IDE (http://www.seeedstudio.com/recipe/11...duino-ide.html).
These are becoming pretty popular for home automation and monitoring systems as they are easy to program and sensors/modules are readily available for just about any type of application.
Anyway, I've programmed this one to host a web page, which the user must enter a code to open the garage door. They also have to have a device that is on my secured home wifi. So any of my family members that have their phone connected to my wifi can open the door.
This is the proto type, simply just the nodemcu (3.3v at pins), a logic level converter for 3.3v to 5v connections, and the relay (5v). It has 3 other pins for door sensors to show if the door is opened or closed.
I tapped it into my opener button to test it out, the door sensors aren't connected yet in this video, and I bypassed the door code for testing.
With this, any family member can open the door and I can do it for them remotely if need be. I also plan to send some messages to my email when the door is opened and closed.