intro

Hi, in this project we are going to make a motion detection alarm with IMU 6050, it is a 3-Axis Accelerometer and Gyro Sensor module. By using this, if small movement is detected by the IMU , it will trigger a sound in the buzzer . Basically it will alert you if an object moves even if it is supposed to be stationary , like a door , home appliance ,or drawer. You can attach this device to any surface with a double tape . It is also useful for monitoring children and elderly people.

How to use it

Activation sequence 

After powering on the alarm will not be activated.For activating this alarm you need to press down the push button then you will hear one beep sound which indicates the activation sequence is successful.

Stand by sequence 

After pressing the button we will have 4 seconds to place this alarm , any movement happening during this 4 seconds will be ignored . 

Detection sequence

After the stand by sequence you will hear two beep sounds which  indicate the Detection sequence is started . From here the alarm is fully armed. Any small movements happening in 3 axis of the device will be detected and trigger this alarm  continually for 10 seconds . After this alarm will be offline we need to reboot the alarm with the power switch and again go through the activation sequences.

We can customize the stand by time , alarm duration, and movement threshold (sensitivity) from the code.so let's get into it 

[ product type image with info graphics]

Supplies

Parts 

Tools

Glue gun

Soldering iron

3d printer 

Step 1 Modeling in Autodesk Fusion 360 and 3d printing 

[ wire frame photo of the model ]

Used Fusion 360 to plan and design my project. The main body is designed to hold the battery and electronics without needing screws—it just snaps into place. To make sure everything stays secure, I used some hot glue. I found some accurate models of the modules online. that made the design process much easier, all design files are given below

I'm not going in depth into the design process but i will show you how i achieved this design on the front side of the 3d print 

[ Details of modeling the front pattern ]

After the design i 3d printed all the parts

Step 2 Uploading Code to XIAO

I always like to upload the code to the microcontroller before assembly. Here we are using a tiny Xiao ESP32C3 from the Seeedstudio.i choose this because i have to make this device small as possible , xiao is very small version of ESP32C3 , also it has battery protection chip built-in so be we dont need external BMS on it, so we can save space in it 

I am using Arduino IDE for flashing the code. Follow these tutorials for setting up IDE for XIAO ESP32C3 and learn more about this board. Make sure to install Adafruit_MPU6050.h library before compiling .

https://www.youtube.com/watch?v=qNzlytUdB_Q&t=944s

 Code

#include <Wire.h>

#include <Wire.h>

#include <Adafruit_MPU6050.h>

Adafruit_MPU6050 mpu;  // Create the sensor object

const int buttonPin = 2;

const int buzzerpin = 11;

const int standbyDelay = 4000;

const int alarmDuration = 10000;

const int movementThreshold = 12;

unsigned long buttonPressTime = 0;

unsigned long activationStartTime = 0;

bool alarmActive = false;

bool inStandby = false;

void setup() {

  Serial.begin(9600);

  while (!Serial) {

    delay(10);

  }

  Serial.println("Motion detection alarm system starting...");

  pinMode(buttonPin, INPUT_PULLUP);

  pinMode(buzzerpin, OUTPUT);

}

void loop() {

  // Button press handling and activation sequence

  if (!digitalRead(buttonPin)) {

    buttonPressTime = millis();
...
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