testing

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Basics of Odometer You Must Understand-Manu

Introduction
 

Planning to purchase a new 4-wheeler for your family? Indeed, a great step, but hold on; are you familiar with the nitty-gritty of automobile? Do you possess knowledge of the basic terms associated with a 4-wheeler? Follow the link to make yourself acquainted with the basic terminology and then travel along the article to understand – what is Odometer? And how does it function beneath the hood?

Definition

Even if you are an automobile fanatic, the possibilities of you being unaware of the literal meaning of the term Odometer cannot be ruled out. A combination of the gear assembly and several rings, Odometer in the simplest way can be defined as a device which showcases the total distance traveled by a 4-wheeler by sensing the rotations of a wheel.

Basic Structure

Other than gear assembly and rings, driver cable is another important part of the Odometer device as it connects the wheel to the gear assembly. With every wheel rotation, driver cable spins along with it transferring the motion of wheels to the gear assembly and bringing the gears in set motion.

Image – 1 titled: “gear-position”

The odometer is surrounded by the gears each located at a specific position(as shown in the image above). If you are interested in seeing how Odometer looks like, remove the gears with utmost caution and you would get to see how Odometer looks (shown below)

Image – 2 titled: odometer-look

As you just noticed, the primary ring of the device connects to gear-4 setting it in motion. Understanding how the rings function, let us take a clear look at the design again.

Image – 3 titled: “image-showing-white-gear”

The odometer assembly comprises 6 different rings connected to each other in a similar fashion. Take a look again to notice a distinct white structure present beneath the rings. This white structure covered with plastic plate shows some teeth through a small cut in the plastic plate.

To figure out the exact location of both the white structure and the plastic plate, take a closer look at the image below.

Image – 4 titled: exact-position-of-white-structure-and-plastic-plate

If you focus on the second ring, you would again notice a white structure under a plastic plate. However, to facilitate the connection between the white gear in the ring and white ring, a small semicircular cut is made onto the plate.

Image – 5: Please join images titled 1.png and 2.png together and insert it here

The plastic plate in discussion here also comes with a shaft whose main role is to pass through the gear and allow smooth movement of the gear within the ring. Flip the image and you can clearly see the internal structure of the white ring in a way that two teeth carved out in the structure are also clearly visible to naked eyes.

If you wish to see a more clear picture of the structure without the ring, (checkout the image below) which shows the back and front view of the ring. All the rings are designed the same way wherein one side showcases teeth running along the entire circumference, while the alternative side shows only two teeth.

Image – 6: Please merge images titled 3.png and 4.png and insert the combined image here

The next image (shown below) shows all the subsequent units merged into one and the placement of rings inside the odometer

Image – 7 titled: entire-arrangement-of-rings

Rotation Principle of Rings

I hope you do remember the role of Driver cable? In case, you can’t recall, let me remind you through these steps while also explaining to you the process of how the rings rotate:

• The driver cable sets up the gear assembly into motion
• The blue gear of the assembly connected to the white ring sets it in motion
• With every movement of the white ring, the outer teeth start their rotation on the outer track. It considerably smoothens the motion of the white ring
• As soon as the white ring completes round-1 (0-9), teeth on the white ring and gear present on the black ring connect
• The connection gives a push to the teeth of small white gear which simultaneously sets the black ring into motion

Note: The connection established between the teeth of small white gear and the black ring ensures a certain amount of force being applied on the latter.

For every movement of white gear, the black ring rotates by one point. Once black ring finishes its first round, ring 1 gets released and the same process is followed by ring 2, ring 3 and all the rest rings present in the odometer.

As clearly depicted in the image below, the black colored tooth is deeper than the red one. Please note one important fact here that the alternate tooth on the gear is specifically carved out with varied depth. Do you know why this happens?

It’s because post-round-1, the tooth of the white ring connects with the gear. What happens is this:

• The first tooth of the white ring pushes the black tooth of the white gear
• The red tooth passes by without any contact with the red tooth of the white gear

This bifurcation of internal movement ensures that the black ring moves only by one point. The second tooth acts as a replacement in case the first one gets damaged due to wear and tear.

However, even after the damage, Odometer assembly works perfectly fine because the teeth on the small white gear is developed in a way that the second tooth of the ring passes seamlessly without coming in contact.

_________________________________________________________________________________

Basics of Odometer You Must Understand-Manu

Introduction
 

Planning to purchase a new 4-wheeler for your family? Indeed, a great step, but hold on; are you familiar with the nitty-gritty of automobile? Do you possess knowledge of the basic terms associated with a 4-wheeler? Follow the link to make yourself acquainted with the basic terminology and then travel along the article to understand – what is Odometer? And how does it function beneath the hood?

Definition

Even if you are an automobile fanatic, the possibilities of you being unaware of the literal meaning of the term Odometer cannot be ruled out. A combination of the gear assembly and several rings, Odometer in the simplest way can be defined as a device which showcases the total distance traveled by a 4-wheeler by sensing the rotations of a wheel.

Basic Structure

Other than gear assembly and rings, driver cable is another important part of the Odometer device as it connects the wheel to the gear assembly. With every wheel rotation, driver cable spins along with it transferring the motion of wheels to the gear assembly and bringing the gears in set motion.

Image – 1 titled: “gear-position”

The odometer is surrounded by the gears each located at a specific position(as shown in the image above). If you are interested in seeing how Odometer looks like, remove the gears with utmost caution and you would get to see how Odometer looks (shown below)

Image – 2 titled: odometer-look

As you just noticed, the primary ring of the device connects to gear-4 setting it in motion. Understanding how the rings function, let us take a clear look at the design again.

Image – 3 titled: “image-showing-white-gear”

The odometer assembly comprises 6 different rings connected to each other in a similar fashion. Take a look again to notice a distinct white structure present beneath the rings. This white structure covered with plastic plate shows some teeth through a small cut in the plastic plate.

To figure out the exact location of both the white structure and the plastic plate, take a closer look at the image below.

Image – 4 titled: exact-position-of-white-structure-and-plastic-plate

If you focus on the second ring, you would again notice a white structure under a plastic plate. However, to facilitate the connection between the white gear in the ring and white ring, a small semicircular cut is made onto the plate.

Image – 5: Please join images titled 1.png and 2.png together and insert it here

The plastic plate in discussion here also comes with a shaft whose main role is to pass through the gear and allow smooth movement of the gear within the ring. Flip the image and you can clearly see the internal structure of the white ring in a way that two teeth carved out in the structure are also clearly visible to naked eyes.

If you wish to see a more clear picture of the structure without the ring, (checkout the image below) which shows the back and front view of the ring. All the rings are designed the same way wherein one side showcases teeth running along the entire circumference, while the alternative side shows only two teeth.

Image – 6: Please merge images titled 3.png and 4.png and insert the combined image here

The next image (shown below) shows all the subsequent units merged into one and the placement of rings inside the odometer

Image – 7 titled: entire-arrangement-of-rings

Rotation Principle of Rings

I hope you do remember the role of Driver cable? In case, you can’t recall, let me remind you through these steps while also explaining to you the process of how the rings rotate:

• The driver cable sets up the gear assembly into motion
• The blue gear of the assembly connected to the white ring sets it in motion
• With every movement of the white ring, the outer teeth start their rotation on the outer track. It considerably smoothens the motion of the white ring
• As soon as the white ring completes round-1 (0-9), teeth on the white ring and gear present on the black ring connect
• The connection gives a push to the teeth of small white gear which simultaneously sets the black ring into motion

Note: The connection established between the teeth of small white gear and the black ring ensures a certain amount of force being applied on the latter.

For every movement of white gear, the black ring rotates by one point. Once black ring finishes its first round, ring 1 gets released and the same process is followed by ring 2, ring 3 and all the rest rings present in the odometer.

As clearly depicted in the image below, the black colored tooth is deeper than the red one. Please note one important fact here that the alternate tooth on the gear is specifically carved out with varied depth. Do you know why this happens?

It’s because post-round-1, the tooth of the white ring connects with the gear. What happens is this:

• The first tooth of the white ring pushes the black tooth of the white gear
• The red tooth passes by without any contact with the red tooth of the white gear

This bifurcation of internal movement ensures that the black ring moves only by one point. The second tooth acts as a replacement in case the first one gets damaged due to wear and tear.

However, even after the damage, Odometer assembly works perfectly fine because the teeth on the small white gear is developed in a way that the second tooth of the ring passes seamlessly without coming in contact.

_________________________________________________________________________________

Project Source Code

Project Source Code

###



//Program to 


/*

  @Project: SIM800_communication_over_MQTT_protocol

  

  @Hardware used:

     SIM800 Module

     Arduino Mega 2560

     LED & 220E resistor

     External Power supply to provide 3.7V to SIM800 module

  

  @Connection:

       SIM800 VCC- External power supply 3.7V

       SIM800 GND- External power supply GND

       SIM800 TX- Arduino Serial1 RX

       SIM800 RX- Arduino Serial1 TX

       SIM800 GND- Arduino GND

       LED cathode- Arduino 2nd pin with 220E resistor in Series   

       LED anode-  Arduino GND 

       External power supply GND- Arduino GND

       

  @Brief Introduction: 

       In this application, We have used SIM800 as our first MQTT client and PC(MQTTlens) as our second MQTT client.

       We are using hiveMQ as our MQTT broker. We are using Arduino Mega to provide serial communication to SIM800 client. 

       PC client is controlling the LED of SIM800 client & SIm800 client is publishing the message "Welcome to GPRS NETWORK!" on topic "GPRS_pub"

*/



//Initialize the SIM to connect to the Network

#define SIM_APN        "Airtelgprs.com"           //APN Name, We are using Airtel network

#define SIM_USER       ""                         //APN USER, We haven't set any username so leave it blank

#define SIM_PASSWORD    ""                        //APN PASSWORD, We haven't set any password so leave it blank


//Include Libraries

#include <Time.h>

#include <sim800Client.h>                        //Include library to initialize SIM800 client

#include <PubSubClient_test.h>                   //Include library to initlize MQTT protocol

#include <TimeAlarms.h>


//Create the instance for SIM800

sim800Client s800;

char imeicode[16];                              //Array initialization for IMEI code so as to find out the device is valid or not.


/*

 MQTT broker on which our device is going to be connected! 

 We are using hiveMQ public broker with unencrypted channel

 We can change the broker according to our requirement

*/

char server[] = "broker.mqttdashboard.com";  


/*

 @fn: void callback(char* topic, byte* payload, unsigned int length)

 @Param: topic, payload, payload length

          Topic: the subsription topic, SIM800 client has subscribed

          payload: the message we receive from MQTT broker on the subcribed topic

          length: the message length

  @return: None

 @brief: This callback function will be called whenever SIM800 client receives the message on topic GPRS_sub/LED_control

*/

void receive_message(char* topic, byte* payload, unsigned int length) 

{

  //handle message arrived

  char mypl[48];

  Serial.println(length);

  memcpy(mypl,payload,length);

  mypl[length]=char(0);

  Serial.print("receive: ");

  Serial.print(topic);

  Serial.print("->");

  Serial.println(mypl);

  

  /*

   When the client receives message 1, LED will be in ON state

   When the client receives message 0, LED will be in OFF state

  */

  if ((char)payload[0]== '1')

  digitalWrite(2, HIGH);

  else if ((char)payload[0]== '0')

   digitalWrite(2, LOW);

}


/*

  @Create the instace for pubsub client

  @Param: server- MQTT server which we have initialized above

          1883- The port on which MQTT broker is listening

          callback- The function for subscription which we have initialized above

          s800- SIM800 client which we have created above

*/

PubSubClient client(server, 1883, receive_message, s800);


/*

  @fn void pub()

  @Param: None

  @Brief: Created a function through which S800 client will publish the message with topic to the MQTT broker

          Whenever we want to change the publish topic and message, we can change from here.

  @return: None

*/

void publish_message()

{

  Serial.print("publish: ");

  Serial.print("message on topic GPRS_pub");

  Serial.print("-> ");

  Serial.println("Welcome to GPRS NETWORK!");

  

  /*

   @fn client.publish(Topic, message);

   @Param: Topic, message

            Topic- The topic on which our message is going to be published

            Message- Any message on the respective topic

   @brief: Call this function to publish the message on MQTT broker

  */

  client.publish("GPRS_pub","Welcome to GPRS NETWORK!");

}


void setup()

{

  

  pinMode(2, OUTPUT);                                       //Initialize LED as OUTPUT so that other client can control this LED

  Serial.begin(9600);                                       //Start the serial communication to debug the communication

  Serial.println("SIM800 MQTT TESTING");

  

  for (int i=0; i<10; i++)

  {

    delay(5000);

    Serial.println("Initialize SIM800!");


   #ifdef HARDWARESERIAL

      if (s800.init( 7, 6)) break; 

   #else

       if (s800.init(&Serial1 , 7, 6)) break;                 //Initialize the serial communication for SIM800 

   #endif

  }


  Serial.println("SETUP SIM800!");

  s800.setup();                                               //Initialize setup for SIM800 client

  s800.stop();                                                //stop any previous network connection of the SIM800 client 

  s800.TCPstop();                                             //Stop any previous TCP connection of SIM800 client

  s800.getIMEI(imeicode);                                     //Get the IMEI code of he SIM800 client                                

  Serial.print("IMEI: ");

  Serial.println(imeicode);


  //From this loop, Start the continuous TCP connection with APN, USERNAME and PASSWORD

  while (!s800.TCPstart(SIM_APN,SIM_USER,SIM_PASSWORD)) 

  { 

    Serial.println("TCPstart failed");

    s800.TCPstop();

    delay(1000);

  }

  Serial.println("TCPstart started");

  

  //From this loop,the client will be connected to the Network

  while (!client.connect(imeicode)) {

    Serial.println("connect failed");

    delay(1000);

  }


  Serial.println("connected");

    /*

   @fn client.subscribe(Topic);

   @Param: Topic

            Topic- The topic on which we receive the message

   @brief: Call this function to subsribe the topic from MQTT broker

  */

  client.subscribe("GPRS_sub/LED_control"); 


  //From this function, the message will be published in a repetitive period of 5 sec to the MQTT broker

  Alarm.timerRepeat(5, publish_message);           

}


void loop()

{

    client.loop();

    Alarm.delay(100); 


}


###
 

Circuit Diagrams

4
MQTT-SN-Architecture-