Is the Garage Door Open? 8266, IPhone/Android




About: Long time software developer having fun with hardware!

I just completed a 8266 garage Door opener ( ) After completing it I thought I really need a way to know if the door is actually opening and wouldn't it be handy to know if the door was still open. I thought of several ways in which I could do this with things like limit switches, distance sensors or even magnets. In the end what I decided to do was use a 10 turn Potentiometer (bar spins 7 times from open to close) mounted to the spring bar to measure the distance the door was open. Works great, and now I will always know how open/closed the door is.

You will need

1) an 8266 Board

2) a 10 turn Potentiometer

3) assorted wires

4) spur gear


Step 1: Add a Spur Gear to the Inside of the Spring Bar on the Garage Door.

In this step you just add a spur gear to the bar that has the spring for your garage door.

My garage door has a spring on the front of the door that is mounted on a bar with pullies on the end. All I did was take a spur gear I had from some hobby stuff I used to do and sanded it down to fit the hole in the bar. This was easy to do as I just put the gear on a drill bit and then took some sand paper to it while it was running on my drill press. Once I had it to the right size, I just glued it in to the hole in the bar and let it dry.

Step 2: Create a Mounting Bracket to Hold the Potentiometer

I took some aluminum bar that I had and just drilled an 8mm hole through it, then bent it so it would fit to another hole in the door rail. I took a bolt and nut and tightened that down.

Step 3: Put the Potentiometer in the Bracket and Screw It to the Spur Gear

Take the Potentiometer and remove the nut off the shaft. Put the Potentiometer in the bracket and then screw down the nut to hold it in place. Now, make sure the Potentiometer is turned to the completely closed position. Then spin it back about a 1/2 turn then insert the shaft in to spur gear and screw that down tight. Then finally mount that to the garage door rail to hold it in place.

Step 4: Solder the Contacts on the Potentiometer to a Piece of 3 Wire.

I used some Cat 5 I had lying around, I just stripped three wires, one for positive, negative and signal. Then I soldered the wires to the Potentiometer.

Step 5: Add the Wires to the 8266

Once you have the Potentiometer soldered to the wire, then move the other end of wire to the 8266. Hook the 3.3v to the positive wire, the ground to the ground and finally the signal wire to A0..

Step 6: Add a Gauge Control to Your Blynk and Hook to A0

Hooking this up for display is easy with Blynk, just add a new guage control to your form and hook it directly to A0. You are now done, your display should update and change when you open the door.




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    8 Discussions


    1 year ago

    Have just finished installing exactly this project and i do have to agree this really works so well. Simple solution to a home automation must.. Knowing what state the door is in from anywhere in the world is great and this just works so well..
    Thanks for this project I'm so glad i came across it. Great work.

    1 reply

    Reply 10 months ago

    Richie007 ... What type of gear did you use for the pot? ... Part number? or what the gear fits?


    1 year ago

    Have you thought about adding RFID outside the door for the kids? .. I am prepping to build this same project yet my grandson does not always carry a cell .. but can carry and RFID tag on his back back.. BTW: great project and article! ..


    1 year ago

    How did you program your 8622? Can you give a wiring diagram? Thanks


    2 years ago

    Some of the comments on here should be deleted by the moderators for rudeness and/or sheer stupidity.

    This is pure K.I.S.S. engineering at its finest. A simple and elegant solution.
    Also anyone that's ever had a house with a motorized garage door knows that knowing the door's position is valuable information as for safety reasons these doors will either stop or go back up if they encounter resistance. IE hit something like a car bumper or kid's bike not put away properly.
    IMO, knowing the position of the door is a must have for a smart home integrated door with remote control capabilities.

    Great work OP.

    1 reply

    Reply 2 years ago

    Thanks. No worries on the comments, I have been on the internet for longer than most and I am very aware of Trolls and have a pretty thick skin. If just one person finds it useful, then it was worth my time to enter it. I have more automation instructs coming soon!

    Dui ni shuo de dui

    2 years ago

    The idea is good but the instructable is not detailed enough, please explain us how you did the software part, it seems very very interesting!! :)
    I also don't understand why do you need to use a 10 turn potentiometer: Wouldn't it be the same to just use one limit switch at the bottom of the door? When the swicth is closed then you know that the door is opened end vice versa.
    Would be much cheaper I think. Sure, you wouldn't be able to know its exact position, but how actually this information would be important anyways?

    1 reply
    JeffL117Dui ni shuo de dui

    Reply 2 years ago

    Sure, a limit switch would work, and no it would not be easier to wire than the potentiometer. With Blynk, you just read the value directly right off the A0 wire, no programing required at all. Also, with a limit switch, you only know that it is closed, you don't know if it is trying to close. From a distance, if you close the door and cant see or hear it, it gives you far more feedback.

    As far as the 10 turn, you have to watch the door to understand that. The pole turns 7 times, if you use anything smaller than 7 you will destroy the potentiometer. I choose 10 turn to give it some space to either side in case something slips it wont break.

    As far as more detail, I am planning on adding more today, just wanted to get the skeleton of this up for the people who don't need a lot of detail.