Chathuranga Liyanage
Published © GPL3+

Avoid Injuries with Smart Backpack

Smart Backpack helps you to avoid injuries caused by backpacks by alerting you about improper uses.

IntermediateFull instructions provided3 hours6,868

Things used in this project

Hardware components

Arduino 101
Arduino 101
×1
SparkFun Force Sensitive Resistor
×3
Buzzer
Buzzer
×1

Software apps and online services

Blynk
Blynk
Arduino IDE
Arduino IDE

Story

Read more

Custom parts and enclosures

Enclosure

Schematics

Fritzing Diagram

Code

Arduino101.ino

Arduino
#define BLYNK_PRINT Serial

#include <EEPROM.h>
#include "CurieIMU.h"
#include <BlynkSimpleCurieBLE.h>
#include <CurieBLE.h>
#include <Wire.h>
#include <SPI.h>

WidgetTerminal terminal(V2);

#define center A0                  //Define Sensor pins
#define left A1
#define right A2
#define buz 2

char auth[] = "########";          //Enter your Blynk Authorization Code Here
BLEPeripheral  blePeripheral;

int cal_weight;
int body_weight;
int fc,fr,fl;
int mr,ml,mc,cr,cl,cc;
int tempr,templ,tempc;
int cal_rec=0;
int mem[10];
int val;
int x,y,z,thx,thy,thz;  
int pin1;
int mode = 0;


void get_readings(){
  for(int i=0;i<50;i++){
    fc = analogRead(center);        //Get raw readings from sensors
    fr = analogRead(right);
    fl = analogRead(left);
    thx = CurieIMU.readAccelerometer(X_AXIS);
    thy = CurieIMU.readAccelerometer(Y_AXIS);
    thz = CurieIMU.readAccelerometer(Z_AXIS);
    delay(2);
    }
    fc=fc/50;
    fr=fr/50;
    fl=fl/50;
    thx = thx/50;   //Get the average values of the readings
    thy = thy/50;
    thz = thz/50;
}

void calibrate(){
    while(mode == 1){}

    if (mode == 2){
    get_readings();

    tempr = fr;
    templ = fl;     //Save the values of FSRs
    tempc = fc;
    }

while (mode ==3){}
    
   if (mode == 5){
    get_readings();

    mr = (fr - tempr)/100;
    ml = (fl-templ)/100;
    mc = (fc-tempc)/100;       //Calculate threshold values 
    cr = 1000-(mr*tempr);
    cl = 1000-(ml*templ);
    cc = 1000-(mc*tempc);
    x = thx;
    y = thy;
    z = thz;
    
    EEPROM.write(0,mr);
    EEPROM.write(1,ml);
    EEPROM.write(2,mc);     //Write threshold values to EEProm
    EEPROM.write(3,cr);
    EEPROM.write(4,cl);
    EEPROM.write(5,cc);
    EEPROM.write(6,x);
    EEPROM.write(7,y);
    EEPROM.write(8,z);
    
    
   }
    
}

void active(){
  
  get_readings();

  fc = fc*mc + cc;//Calculate forces on FSRs using pre-saved threshold values    
  fl = fl*ml + cl;
  fr = fr*mr + cr;

  if(abs(fl-fr)>300) {
  tone(buz,300);                //Alerts if straps are unbalanced
  terminal.println("Straps are unbalanced");
  }
  if(fc> 500) {
  tone(buz,600);                       //Alerts if the backpack is overfilled
  terminal.println("Harmful force on the spine.");
  }
  if(fl+fr>cal_weight){ 
    tone(buz,1400);             //Alerts if the backpack is over-weight
    terminal.println("Too heavy");
  }
  
  if (abs(thx-x)>30 or abs(thy-y)>30 or abs(thz-z)>30){    // Alerts about improper angles
      tone(buz,2000);
      terminal.println("Harmful posture detected");
  }
  delay(500);
  digitalWrite(buz,LOW);
}



void setup(){
  pinMode(3,OUTPUT);
  pinMode(left,INPUT);
  pinMode(right,INPUT);          //Setting the sensor pin modes
  pinMode(center,INPUT);
  mr = EEPROM.read(0);
  ml = EEPROM.read(1);
  mc = EEPROM.read(2);        // Read the saved values from EEProm
  cr = EEPROM.read(3);
  cl = EEPROM.read(4);
  cc = EEPROM.read(5);
  thx = EEPROM.read(6);
  thy = EEPROM.read(7);
  thz = EEPROM.read(8); 
  Serial.begin(9600);

  blePeripheral.setLocalName("Arduino101Blynk");
  blePeripheral.setDeviceName("Arduino101Blynk");
  blePeripheral.setAppearance(384);

  Blynk.begin(auth, blePeripheral);

  blePeripheral.begin();
}


void loop(){
  Blynk.run();
  blePeripheral.poll();
  }
  
BLYNK_WRITE(V0){                    //Read the changes in the weight slider
        body_weight = param.asInt();
        cal_weight = body_weight/10;  // Calculate the safe carrying weight
}
  
BLYNK_WRITE(V1){                               // Going to calibrate mode
        pin1 = param.asInt();
        if (pin1 == 1){
          mode = mode+1;
          calibrate();
        }
        
      }
BLYNK_WRITE(V2){
    if(mode==2){
    terminal.print("Put 1kg weight and Press Enter");                                             
    mode = mode+1;
    }                   // Terminal Notifications in the calibration process
    if(mode==3){
    terminal.println("Values Saved");    
    terminal.println("Put 2kg weight and Press Enter");
    mode = mode+1;
    }
    if(mode==6){
    terminal.println("Values Saved");   
    terminal.println("Calibration Succesfull");
    mode = 0;
    active();
    }
}

BLYNK_WRITE(V3){                                          // Enter button
        int pin3 = param.asInt();
        if (pin3 == 1){
          mode = mode+1;
        }
}

BLYNK_WRITE(V4){                                // Turn On/Off the buzzer
        int pin4 = param.asInt();
        if (pin4 == 1){
          tone(buz , 1000);
        }
        if (pin4 == 0){
          digitalWrite(buz , LOW);
        }
}
BLYNK_WRITE(V5){                                  //Turning on the device
  int pinValue = param.asInt();

 if (pinValue == 1){
    while(pinValue == 1){
      int pinValue = param.asInt();

      active();
         
    }
  }
}

Credits

Chathuranga Liyanage

Chathuranga Liyanage

10 projects • 55 followers
Entrepreneur | Founder - SRQ Robotics | Roboticist

Comments

Related channels and tags
  • Arduino
  • Blynk
  • SparkFun