Arduino “having11” Guy
Published © GPL3+

ESP8266 Fall Detector and Alerter

Get alerted if a person falls or pushes a panic button using MyDevice's Cayenne. It is very small with a rechargeable lithium ion battery.

AdvancedFull instructions provided5 hours3,176
ESP8266 Fall Detector and Alerter

Things used in this project

Hardware components

ESP8266 ESP-12E
Everything ESP ESP8266 ESP-12E
×1
Pushbutton switch 6mm
×1
3mm LED
×1
SparkFun Triple Axis Accelerometer and Gyro Breakout - MPU-6050
SparkFun Triple Axis Accelerometer and Gyro Breakout - MPU-6050
×1
Lithium Ion battery 500 mAh
×1
Lithum Ion Battery Charger
×1
SPDT Switch 3 terminal 2 position
×1

Software apps and online services

Fusion 360
Autodesk Fusion 360
Anduino Arduino IDE
Cayenne
myDevices Cayenne

Hand tools and fabrication machines

3D Printer
Soldering Iron

Story

Read more

Custom parts and enclosures

Lower Portion

3D print it.

Top Piece

Button

Schematics

Schematic

Schematic bb yyl7x9dkok

Code

Code

C/C++
// This example shows how to connect to Cayenne using an ESP8266 and send/receive sample data.
// Make sure you install the ESP8266 Board Package via the Arduino IDE Board Manager and select the correct ESP8266 board before compiling. 
#include <Wire.h>
#include <SimpleTimer.h>

const int MPU_addr=0x68;
int16_t AcX, AcY, AcZ, TmP,GyX,GyY,GyZ;
float AcX_calc, AcY_calc, AcZ_calc;
uint32_t lastTime;

//#define CAYENNE_DEBUG
#define CAYENNE_PRINT Serial
#include <CayenneMQTTESP8266.h>

// WiFi network info.
char ssid[] = "ssid";
char wifiPassword[] = "wifi pass";

// Cayenne authentication info. This should be obtained from the Cayenne Dashboard.
char username[] = "username";
char password[] = "password";
char clientID[] = "client-id";

#define LED_PIN 14
#define BUTTON_PIN 12

void check_imu(){
  readIMU();
  Serial.print("AcX: "); Serial.print(AcX); Serial.print("g | AcY: "); Serial.print(AcY); Serial.print("g | AcZ: "); Serial.print(AcZ);
  Serial.println("g");
  if(abs(AcX_calc)> 22000 || abs(AcY)> 22000|| abs(AcZ) > 27000){
    Serial.println("Fall detected");
    int button_val = 1;
    lastTime = millis();
    button_val = digitalRead(BUTTON_PIN);
    while(millis()-lastTime<5000){
      digitalWrite(LED_PIN, HIGH);
      button_val = digitalRead(BUTTON_PIN);
      delay(10); //Debounce
      Serial.println(button_val);
      if(!button_val) break;
    }
    if(!button_val){
      Serial.println("Didn't do anything, button was pressed");
      digitalWrite(LED_PIN, LOW);
      delay(200);
    }
    else{
      alarm();
    }
    delay(50);
  }
  
}

void setup() {
	Cayenne.begin(username, password, clientID, ssid, wifiPassword);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  digitalWrite(LED_PIN, LOW);
  Wire.begin(4,5);
  Wire.beginTransmission(MPU_addr);
  Wire.write(0x6B);
  Wire.write(0);
  Wire.endTransmission(true);
  Serial.begin(115200);
  Serial.println("Wrote to IMU");
  
}

void loop() {
  int button_state = digitalRead(BUTTON_PIN);
  if(!button_state){
    alarm();
    delay(500);
  }
	Cayenne.loop();
  check_imu();
  if(millis()>(pow(2,32)-5000)){
    ESP.reset();
  }
}

//Default function for processing actuator commands from the Cayenne Dashboard.
//You can also use functions for specific channels, e.g CAYENNE_IN(1) for channel 1 commands.
CAYENNE_IN_DEFAULT()
{
	CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
	//Process message here. If there is an error set an error message using getValue.setError(), e.g getValue.setError("Error message");
}

void readIMU(){
  Wire.beginTransmission(MPU_addr);
  Wire.write(0x3B);  // starting with register 0x3B (ACCEL_XOUT_H)
  Wire.endTransmission(false);
  Wire.requestFrom(MPU_addr,14,true);  // request a total of 14 registers
  AcX=Wire.read()<<8|Wire.read();  // 0x3B (ACCEL_XOUT_H) & 0x3C (ACCEL_XOUT_L)    
  AcY=Wire.read()<<8|Wire.read();  // 0x3D (ACCEL_YOUT_H) & 0x3E (ACCEL_YOUT_L)
  AcZ=Wire.read()<<8|Wire.read();  // 0x3F (ACCEL_ZOUT_H) & 0x40 (ACCEL_ZOUT_L)
  TmP=Wire.read()<<8|Wire.read();  // 0x41 (TEMP_OUT_H) & 0x42 (TEMP_OUT_L)
  GyX=Wire.read()<<8|Wire.read();  // 0x43 (GYRO_XOUT_H) & 0x44 (GYRO_XOUT_L)
  GyY=Wire.read()<<8|Wire.read();  // 0x45 (GYRO_YOUT_H) & 0x46 (GYRO_YOUT_L)
  GyZ=Wire.read()<<8|Wire.read();  // 0x47 (GYRO_ZOUT_H) & 0x48 (GYRO_ZOUT_L)
}

void blink_led(int times){
  for(int i=0;i<times;i++){
    digitalWrite(LED_PIN, HIGH);
    delay(50);
    digitalWrite(LED_PIN, LOW);
  }
}
void alarm(){
  digitalWrite(LED_PIN, HIGH);
  Serial.println("Alarm sent!");
  Cayenne.virtualWrite(1,2);
  delay(100);
  Cayenne.virtualWrite(1,0);
  digitalWrite(LED_PIN, LOW);
}

Credits

Arduino “having11” Guy

Arduino “having11” Guy

30 projects • 211 followers
IoT, Arduino, and Raspberry Pi. I can create designs, code, and build projects for only $22/hr. Just message me with your project request.

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