Ever come home in the rain to find the door locked and your keys elsewhere? No? Lucky you then! For those who have had such an experience or never wish to, this project will let you open your garage door with nay but a smartphone/tablet/laptop/WiFi-thing and your super secret password! After all, who leaves their smartphone at home nowadays. The very idea!
All it takes is a network capable Arduino, a relay, a long network cable and a few other bits 'n bobs like wire and a soldering iron.
So how does it work? I'm so glad you asked! The Arduino hosts a little web page on your local network which you can access from any other device on the network, such as your smartphone, just like a normal website. When you input your password, the Arduino triggers a relay that acts like a wired garage door remote that you often see next to the internal door. This sets the garage door opening mechanism into motion, letting you through with the a new felt sense of control over your home!
So, shall we get started then?...
Step 1: Needed Things
- A Freetronics EtherTen or other network capable Arduino board - This is the brains of the operation. It hosts the web page you connect to when you want to open the door and triggers the garage door opener (via the relay) when the correct password is entered.
- A Relay Board to activate the opener - This acts like a wall switch or button but the EtherTen 'pushes' it instead of you. In this case it will emulate the switch in the wall mounted or portable remote that you currently use to open the garage door. This can work alongside the existing buttons and remotes. Either buy one such as this one from dealextreme that I used in my case or make your own with: a relay, a transistor (any small signal one such as a 2N2222 or 2N3904 should do) to turn the relay on and off, and a flyback diode to protect the transistor and EtherTen from the voltage spike generated by the inductive load of the relay coil when it is turned off (such as a 1N4001).
- A Case - For those with access to a 3D printer or who feel like giving a 3D printing service such as Ponoko, i.materialise, Sculpteo or Shapeways a try, you can make the "EtherTen Enclosure" used in this project. This is available on this projects GitHub repository will house both the Freetronics EtherTen and dealextreme relay board nicely. Just hit the "Download ZIP" button on the bottom right to download it and other necessary project files. You will need to print off a top, a base and 4 clips. To mount things together you will need 12, M3 sized, 6 mm long (shaft length) screws and an M3 tap or 12 self-tapping screws of the similar size. Sometimes I've gotten away with using 'normal' (machine) screws instead of self -tapping but it depends on how soft the plastic is. The reason four of the screws that can be seen in the image above are plastic is so that the colour matches the case and looks nice.
- A Connector and Dual Conductor cable to go between the relay board and the opener or remote you wire it to - I used a 3.5 mm jack and plug usually used for audio equipment and some thicker than needed wire. The length of wire required depends on the distance between the opener or remote you will wire into, as informed by the next step, and the nearest convenient spot to place the box containing the relay board and EtherTen. If you are truly averse to soldering you could omit this and instead open the box up and unscrew the terminals each time you wish to disconnect it.
- Three Male to Female Jumper Wires to connect the relay board to the EtherTen with.
- Network Access - This can be a long Ethernet cable as in my case or an old wireless access point or router.
- A Power Supply to power the EtherTen. This needs to be around 6-9 V DC (7.5 V ideally) and at least 300 mA for the EtherTen to be happy. See Appendix A (Step 10) for how to check if any old wall plug packs that might be lying around will do the job. Advanced makers may be able to get some Power over Ethernet (PoE) thing to work instead but that is beyond my knowledge.
Tools that will be needed are:
- A multimeter
- Flat head and philips screw drivers
- A ruler
Tools that will be useful are:
- A pair of pliers
- A wire stripper
- A soldering iron