TripPing: a Trip Wire Alarm (Rechargeable)

1. Introduction:Here's TripPing, a simple Rechargeable Trip Wire Alarm I have designed involving no microcontroller and just a few readily available electronics. You will be notified of an intruder by the sound of the buzzer on the device.

With a few electronics and a simple circuit, you can make your own TripWire Alarm, recharge it and Use it where ever u want.

So apart from the materials listed,here's the most important part:

2. For the string of the trip wire alarm, I have used Dental flossOral B sells standard dental floss or you could use anything else but make sure to choose something that is more the length of the room door that you are planning to use it on.

Make the connection with the electronics as shown in the circuit diagram.

NOTE: Make sure to connect the two ends of the limit switch and not the middle one.

Concept:

When the extreme terminals of the limit switch are connected, the switch acts as a closed circuit. Therefore, when the limit switch is pushed, the circuit is open.

So temporarily before assembling everything, the buzzer will keep buzzing loudly.

Use a zip tie to temporarily push the switch. Refer to the below image in this step.

3. Finally Assemble the circuit onto the CAD parts:

Use the holder.stl part.

I used 3M double tape for TP4056 and Lipo battery.

• I used Hot Glue for the Limit Switch
• NOTE: For the buzzer, I have used mine which is exactly fitting in the design. Make sure your buzzer is 25mm or less than that.
• In the case of a smaller buzzer, just Hot Glue it to the side of the cylindrical shape.

Refer to the video for a better view.

4. Setup the Trip Wire:

Dental floss is perfect for this application as its strong and also easily available.

You will need the following 3D PRINTED PARTS:

• string_tightener_base.stl
• string_tightener_nut.stl

Pull required amount of string/dental floss. Make sure it is a bit longer than your door length or walkway length.

• Insert the string into the hole of the string_tightener_base.stl part.
• Next, screw the string_tightener_nut.stl onto the string_tightener_base.stl part.
• This ensures the string is tight and wont come off.

This step is the same as the previous step:

• Insert the other end of the string into the hole of the trigger.stl part.
• Next, screw it using the string_tightener_nut.stl part.

Observe the little rectangular slab above the limit switch.

• We will place our trigger part between the slab and the switch to keep the buzzer off.
• Notice the second image, and insert it the same away.
• Now the Whole system is set.

5. Cover the electronics:

Lastly to cover all the electronics, I have used the parts:

• top_plate.stl
• tripPing_letters.stl

Simply insert the letters into the corresponding gaps.

Finally stick the top plate onto the main system using double tap on the battery or you can hot glue it too.

6. Setup Your Alarm!:

Best preferred to set it up in the entrance of a room.

So, I then used 3M double sided tape on the back of the string_tightener_base.stl part as shown in the image.

Now stick them on the doorway borders.

NOTE: you can adjust the tightness of the string by unscrewing pulling how much ever you want and screwing it back.

7. WORKING:

Every time someone enters, the trigger slips out of place. The limit switch is no longer pushed. Therefore the circuit becomes closed and you hear a loud buzz.

Reset it by inserting the trigger back into place.

Well that's it!

Checkout the video too!

8. Charge the device:

You can recharge the battery using the c port(as shown in the image) and reuse it where ever you want.

Do leave a like if this amused you!