Introduction: Smartphone Controlled Door Locking System

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Don’t lie when we say that all of us at some point in time feel way too tired or lazy to get up and go from room to another just to open the door. Y’all have been there. For sure. Some of you may also have been the victim of a sibling rivalry where one locks the other inside or outisde the room. But guess what! None of this happens anymore, mate! Here’s something that is going to turn the tables in your favour! Presenting you the *drum roll* Dabble Controlled Door Lock - a smart lock that can be controlled using Dabble, our ingeniously developed project-making application. Some jumper cables, a servo, your buddy-in-need evive, and a dash DIYing skills is what you need to make this project and soon control shall be in your hands! *wicked laugh*

So, what are you waiting for?! Get on board!

Step 1: Things You'll Need


  • evive
  • Bluetooth Module HC05
  • Metal Servo
  • Glue Gun


Step 2: Making of the Lock

All the components that we need to make a locking system are made up using 3D Printing Technology.

Take the latch and the latch holder.

Insert the latch into the latch into the holder.

Step 3: The Opening and the Closing Mechanism

We are using the Metal Servo for the same purpose.

Take the servo and insert it into the space given in the latch holder and fix it using Hot Glue.

You will notice the free servo head. Upon this, we will be fixing our Gear.

Make sure the teeth of the gear matches the ones on the latch.

Step 4: Connection

Connect the Metal Servo to the Servo Channel 1 i.e. S1 of evive.

Connect the Bluetooth Module as shown in the figure.

Step 5: The Working

Normally break-in occurs because the intruder breaks the lock which is on the front door. If the lock would be on the back of the door, possibilities of break-in reduce.

Now, if the door is locked from inside, how are we going to open. Guess what? You have your Smartphone which will be able to do it.

The Dabble app helps us to do that.

Open the app and connect your Bluetooth Module. Choose the option of Terminal.

Here you can either give commands by typing it or voice command.

Once you send 'open the door', evive asks for the password.

The password should already be set by you in the code.

If the password entered by you is Correct, the door opens. But for a short duration of time.

If the password entered is wrong, the door will remain closed.

Step 6: Code

The following Arduino Code should be uploaded to perform the required action.

Step 7: Conclusion

With this, you once an ordinary door is now going to be a smart one! Psst! We have something really exciting to tell you before you leave. We’re going to launch an amazing STEM product this month that is going to make electronics, programming, and robotics child’s play! Head over here to know more about it and perhaps even reserve one for yourself as well to get some super special perks!

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