Created July 31, 2018

Tracking the missing salmons using Sigfox IoT solution

Design and construction of a device able to transmit data packages over Sigfox-LPWAN received from an RS485 tracking unit.

Things used in this project

Hardware components

Arduino UNO

SIGFOX Breakout board BRKWS01

RS-485 Converter Module - MAX485

Story

The Swedish company IoT-Sweden is responsible for the establishment of Sigfox-LPWAN in Sweden and I was lucky to be able to collaborate with them during my bachelor thesis at Chalmers University. I wanted to connect my line of studies as electrical engineer to provide substantial solutions to environmental issues. I contacted the Counties agency of Gothenburg Sweden to discuss what possibilities Sigfox technology could provide in terms of sustainabillity. One possebility that came to mind by the consultants at the Counties agency was "The missing salmon project". The missing salmon project aim to understand and prevent the rapid decline of the Atlantic salmon in countries across Europe.

The Counties agency together with the University of Gothenburg attempt to map the movement of salmon during their movement from Göta river dams to the Atlantic ocean. In order to do this are tracking devices placed along the stream to register when and where salmon implanted with tags passes. Information is gathered by the device containing water temperature, the amount of registered fishes and their identity ID. However, the data need to be accessed manually at the location where the tracking device is placed, which is both time consuming and expensive. My objective became to develop a prototype to intergrate the tracking units to Sigfox-LPWAN and wireless provide periodic data feed concerning the fish movement.

To construct a prototype able to receive, process and transmit data research about the tracking unit and what type of communication it utilizes was gathered. The arduino needed to be programmed to ask for the tracking unit for specific information and process the data to the correct format.

The unit used to track the Atlantic salmon in the stream.

The tracking unit utilizes RS485 communication which is different to the serial communication used by the arduino. Therefore, a MAXRS485 module which works as a translator between RS485(115200 baud) and TTL UART(9600 baud) was intergrated to establish connection between the tracking unit and the arduino.

A MAXRS485 modul.

The cable between the tracking unit and MAXRS485 modul was constructed using twisted cable where connectors to fit the sockets were soldered to the cable ends.

Presents the modifies cable between the tracking unit and MAXRS485.

Connection between the tracking unit and arduino enabled information to be exchanged between the devices. The next step in the process was to integrate the Sigfox modem to enable wireless communication to the cloud.

The sigfox modem used for connecting the prototype to Sigfox-LPWAN.

The final schematic of how the wiring and its components was connected is found within "Attachments".

The original idea was to ask the tracking unit for the relevant information, process the data and transmit the data every ten minutes. The limitation of transmittin every ten minutes is due to EU regulations of the ISM-band utilized by Sigfox. In between the transmission, the prototype was supposed to enter power saving mode for optimization of the power efficiency. However, this idea was not achieved due to interference when large amount of data was transmitted from the tracking unit. I was unable to find a solution to the interference issue due to time constraints. Therefore the built in periodic data transmission on the tracking device was used to receive the relevant information.

The following flowchart was produced to easily produce the code enabling the desired functionality of the device.

Flowchart of the code implemented on the arduino.

The interference caused the IoT-prototype to achieve lower power efficiency than what was expected from the beginning. Furthermore, the prototype was able to receive, process and transmit data from a tracking unit via Sigfox-LPWAN which provided the missing salmon project with data every ten minutes regarding the Atlantic salmon in Göta river.

The people involved in the project was grateful to receive this information and by knowing the exact time the salmon starts its journey towards the sea it will be easier to put constructions along the stream on hold that might have negative consequences on salmon population and thereby decrease potential disturbances.

Me posing with the device placed in a tree along the stream.

I would finally like to thank Mikael Falkvidd for all the support during the project. The actual thesis with more detaild descriptions regarding project will be published in the next month.

Code

Program intergrated on the arduino

//Author: Mattias Blinge
//Date: April 2018


/*-----( Import needed libraries )-----*/
#include <AltSoftSerial.h>         
// Library which enables transmission and receiving through pin 8 and 9
#include <SoftwareSerial.h>        
// Library which enables transmission and receiving through pin 10 and 11
/*-----( Declare Constants and Pin Numbers )-----*/
#define SSerialRX        10        
//Serial Receive pin TO RS485
#define SSerialTX        11        
//Serial Transmit pin TO RS485
#define SigfoxRX         8         
//Send message via Sigfox
#define SigfoxTX         9         
//Send message via Sigfox

#define SSerialTxControl 12        
//RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW
#define NORMAL_DELAY 500           
// In milliseconds
#define SEND_INTERVAL 600000       
// Defining 10 minutes in milliseconds
#define ComputerSerial Serial

AltSoftSerial altSerial;                                
// Set up the serial port connected to the Sigfox Modem


SoftwareSerial RS485Serial(SSerialRX, SSerialTX);       
// Set up the serial port connected to TBR


/*-----( Declare Global Variables )-----*/

String sendtoTBR;
int FishInt;
unsigned long lastSendTime;

/*---------------------(Initiating  Startup Code)-------------------------- */

void setup() {
  altSerial.begin(9600);                          
  // Defining baud rate from Arduino to Sigfox Modem
  ComputerSerial.begin(9600);                     
  // Defining baud rate to computer
  RS485Serial.begin(115200);
  pinMode(SSerialTxControl, OUTPUT);              
  // Defining

  digitalWrite(SSerialTxControl, RS485Receive);   
  // Initiate Transceiver
  exitTBR();                                      
  // Making sure TBR is in listening mode
  ComputerSerial.println("Booting");      
  // Testing that communication with computer is established
  delay(10000);
  altSerial.println("AT\$SF=FFFFFF");              
  // Test for coverage at start up
  lastSendTime = millis();                        
  // Reference time for While-loop
}

/*------------------(Loop process)---------------------*/

void loop() {


/*-----( Declare Local Variables )-----*/
  int numTempInt;
  String numTemp;
  String data_received;
  String SigFoxmess;
  int IDarray0;
  int IDarray1;
  int IDarray2;
  int IDarray3;

  while ((millis() - lastSendTime) < SEND_INTERVAL) {            
  // Run program inside the loop for 10 min


    if (RS485Serial.available() > 0)                             
    // If data is received from the TBR proceed with the processing of the data
    {
      data_received = RS485Serial.readStringUntil('\n');         
      // Data is placed in a string
      String SensorCheck = getValue(data_received, ',', 6);
      if (SensorCheck == "69") {                                 
      // Find out whether the data is a "Tag detection" och "Sensory data"
        numTemp = getValue(data_received, ',', 3);               
        // Place the temperature value in String
        numTempInt = numTemp.toInt();                            
        // Convert numTemp from "string" to Integer.

      }
      else {                                                     
      // If the data received is a "tag detection"
        String IDtag1 = getValue(data_received, ',', 4);
        IDarray3 = IDarray2;
        IDarray2 = IDarray1;
        IDarray1 = IDarray0;
        IDarray0 = IDtag1.toInt();                               
        // Convert IDtag1 from "string" to Integer

      }
      getNumFishes();                                            
      // Enter "getNumFishes" to fetch total number of tag detections from TBR
      rs485Read(500);
      /*--------------(For testing purposes)----------------*/

      //ComputerSerial.println(numTempInt); 
      // Display Temperature on terminal as int
      //ComputerSerial.println(IDarray[0]);
      //ComputerSerial.println(IDarray[1]);
      //ComputerSerial.println(IDarray[2]);
      //ComputerSerial.println(IDarray[3]);
      //SigFoxmess = FishInt + numTempInt + IDarray[0]+ 
      IDarray[1] + IDarray[2] + IDarray[3];
      //ComputerSerial.println(SigFoxmess);




      //-----------(Making Sure StringFish is 16 bit)-------------
      String StringFish =  String(FishInt,  HEX);        
      // Convert value to Hexadecimal

      while (StringFish.length() < 4) {                  
      // Add "0"s from the left until length equal to 4.
        StringFish = 0 + StringFish;
      }

      //-----------(Making Sure StringTemp is 16 bit)-------------

      String StringTemp = String(numTempInt, HEX);      
      // Convert value to Hexadecimal

      while (StringTemp.length() < 4) {                 
      // Add "0"s from the left until length equal to 4.
        StringTemp = 0 + StringTemp;
      }

      //-----------(Making Sure StringIDtag0 is 16 bit)-------------

      String StringIDtag0 = String(IDarray0, HEX);      
      // Convert value to Hexadecimal

      while (StringIDtag0.length() < 4) {               
      // Add "0"s from the left until length equal to 4.
        StringIDtag0 = 0 + StringIDtag0;
      }

      //-----------(Making Sure StringIStag1 is 16 bit)-------------

      String StringIDtag1 = String(IDarray1, HEX);      
      // Convert value to Hexadecimal

      while (StringIDtag1.length() < 4) {               
      // Add "0"s from the left until length equal to 4.
        StringIDtag1 = 0 + StringIDtag1;
      }

      //-----------(Making Sure StringIStag2 is 16 bit)-------------

      String StringIDtag2 = String(IDarray2, HEX);      
      // Convert value to Hexadecimal

      while (StringIDtag2.length() < 4) {               
      // Add "0"s from the left until length equal to 4.
        StringIDtag2 = 0 + StringIDtag2;
      }

      //-----------(Making Sure StringIStag3 is 16 bit)-------------

      String StringIDtag3 = String(IDarray3, HEX);      
      // Convert value to Hexadecimal

      while (StringIDtag3.length() < 4) {               
      // Add "0"s from the left until length equal to 4.
        StringIDtag3 = 0 + StringIDtag3;
      }

      //-----------(Concatinating the Sigfox message)-----------

      SigFoxmess = String("AT\$SF=" + StringFish + StringTemp + StringIDtag0 + 
      StringIDtag1 +  StringIDtag2 + StringIDtag3);

      /*----------(For Testing Purposes)---------------*/
      //ComputerSerial.println(StringFish);   
      //Print Hex value of number of Fish passed
      //ComputerSerial.println(StringTemp);   
      //Print Hex value of last temperature read
      //ComputerSerial.println(StringIDtag0); 
      //Print Hex value of last Fish tag scanned
      //ComputerSerial.println(StringIDtag1); 
      //Print Hex value of 2:nd last Fish tag scanned
      //ComputerSerial.println(StringIDtag2); 
      //Print Hex value of 3:rd last Fish tag scanned
      //ComputerSerial.println(StringIDtag3); 
      //Print Hex value of 4:th last Fish tag scanned
      //ComputerSerial.println(SigFoxmess);   
      // Print whole message


    }
  }
  altSerial.println(SigFoxmess); 
  // Send message from Arduino to Sigfox modem.
  lastSendTime = millis();
}


//---------------FÅ FISKSTRÄNG-------------------
String getNumFishes() {                           
// Fetches the amount of tag detections made by the TBR
  sendTBR();                                      
  // Place TBR in listening mode
  rs485Send("TD?");                               
  // Send "TD?" to TBR
  String response = rs485Read(500);               
  // Read the from TBR for 500ms
  exitTBR();                                      
  // Exit TBR listening mode
  String numFishes = getValue(response, '=', 1);  
  // Process data received in "getValue" to fetch number of tag detections.
  FishInt = numFishes.toInt();                    
  // Convert numFishes from "string" to Integer.
  //ComputerSerial.println(FishInt);              
  // Prints amount of tag detections made on computer monitor
  return numFishes;

}

/*
  //---------------Get TEMPERATUR-----(Not used)------------
  String getNumTemp() {
  sendTBR();
  rs485Send("PS?0001101");
  String response = rs485Read(1000);
  exitTBR();
  String numTemp = getValue(response, ',', 6);
  //ComputerSerial.println(numTemp);
  ComputerSerial.println(response);
  return numTemp;

  }
*/
//----------------------STRING SEPARATION------------------------

String getValue(String data, char separator, int index)                   
// Splitting a string into pieces based on separation character 
// and returns the item inbetween.
{
  int found = 0;
  int strIndex[] = { 0, -1 };                                             
  // Contains the location of the beginning and end of the desired string
  int maxIndex = data.length() - 1;                                       
  // Define the length of the string

  for (int i = 0; i <= maxIndex && found <= index; i++) {                 
  // If the end of the data string is not reached and the
  // index separator is not found, proceed
    if (data.charAt(i) == separator || i == maxIndex) {                   
    // If the character at position i is equal to separator character
      found++;                                                            
      // Increment "found"
      strIndex[0] = strIndex[1] + 1;
      strIndex[1] = (i == maxIndex) ? i + 1 : i;
    }
  }
  return found > index ? data.substring(strIndex[0], strIndex[1]) : "";   
  // Returns the data between strIndex[0] and strIndex[1]
}

//---------------TBR COMMANDS-------------------------

void exitTBR() {
  rs485Send("EX!");                               
  // Command to exit Listening mode of the TBR
  rs485Read(500);                                 
  // Flush the "EX!" response
}

void sendTBR() {                                  
// Placing TBR in listening mode
  digitalWrite(SSerialTxControl, HIGH);           
  // Setting TX pin to "1"
  delay(10);
  RS485Serial.print("T");
  delay(2);                                       
  // Transmitting the sequence "TBR" to the TBR places it in listening mode
  RS485Serial.print("B");                         
  // For the TBR to interpret the sequence delays
  delay(2);                                       
  // must be placed between the letters.
  RS485Serial.print("R");
  RS485Serial.flush();
  digitalWrite(SSerialTxControl, LOW);
}


void rs485Send(String sendtoTBR) {                
// Sub function of which writes transmitted data to the TBR
  digitalWrite(SSerialTxControl, RS485Transmit);  
  // Place MAXRS485 in transmit mode
  delay(10);
  RS485Serial.print(sendtoTBR);                   
  // Transmit "s" to TBR
  RS485Serial.flush();                            
  // Wait until the all has been printed before proceeding
  digitalWrite(SSerialTxControl, RS485Receive);   
  // Place MAXRS485 in receiving mode
}

//------------------READ FROM SERALPORT---------------------------------------


String rs485Read(unsigned long timeOutMS) {
  RS485Serial.setTimeout(timeOutMS);                        
  // Wait before proceeding
  digitalWrite(SSerialTxControl, RS485Receive);             
  // Enableing receiving mode from TBR
  String readTBR = RS485Serial.readStringUntil('\n');       
  // Place data form TBR in "s"
  sendtoTBR.trim();                                         
  // Deletes white-spaces from the beginning and end of the string
  if (sendtoTBR.length() == 0) return "";                   
  // If nothing is read, return nothing.
  return readTBR;
}

//  --------------------------------------------------------------

Credits

Mattias Blinge

1 project • 1 follower

Tracking the missing salmons using Sigfox IoT solution

Things used in this project

Hardware components

Story

Schematics

Fritzing schematic of the circuit

Code

Program intergrated on the arduino

Credits

Mattias Blinge

Comments

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Tracking the missing salmons using Sigfox IoT solution

Tracking the missing salmons using Sigfox IoT solution

Things used in this project

Hardware components

Story

Schematics

Fritzing schematic of the circuit

Code

Program intergrated on the arduino

Credits

Mattias Blinge

Comments