Difference between revisions of "S16: Warriors"

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−	=== Grading Criteria ===	+	== Wifi based sensor system ==
−	<font color="green">	+	This is an IoT based sensor system which allows sensor data to be accessed over the internet from anywhere.
−	*  How well is Software & Hardware Design described?
−	*  How well can this report be used to reproduce this project?
−	*  Code Quality
−	*  Overall Report Quality:
−	**  Software Block Diagrams
−	**  Hardware Block Diagrams
−	**:  Schematic Quality
−	**  Quality of technical challenges and solutions adopted.
−	</font>
−	== Project Title ==	+	== Abstract ==
−	Internet of Things based GPS Tracking System	+	The most basic aspect of an IoT system is the network of devices/objects. IoT allows objects to be sensed and controlled remotely across existing network infrastructure. This project is based on the same fundamental. SJOne board senses temperature, light intensity, and GPS (SIM800) module. WiFi capability is added to SJOne board using ESP8266 serial module. SJOne(client) transmits the sensor data over the network to the server. Raspberry Pi 3 acts as a server, receives the data from the client and stores it in mysql database. A php webpage takes the most recent entry from database and displays on the webpage along with map.
−	== Abstract ==	+	== Objectives ==
−	Internet of Things based GPS & GSM tracking system with a user-friendly web page interface that enables transportation industry to keep track of their vehicle with the timestamp. This project also involves the data collection from different sensors like the temperature sensor and the light sensor that can help to provide an alert if required conditions are not matched for carrying some sensitive goods like medicine.	+	1) Set up sensor hub:
		+	* Interface GPS module with SJOne
		+	* Write drivers to access the temperature and light intensity sensors on-board SJOne
		+
		+	2) Set up TCP Client:
		+	* Interface the WiFi module with SJOne board and implement a TCP client
		+	* Write device driver to transmit data from SJOne client to the server
−	== Introduction ==	+	3) Set up TCP Server:
−	The project shows the implementation of Internet of Things based GPS tracking system with an add-on feature that is the collection of data from sensors attached to the microcontroller. The data is being stored on APACHE web server running on raspberry pi to eliminate the problem of memory storage space on the hardware. The output is being shown on the web page with a user-friendly interface that will show the latitude & longitude of the current location, temperature, and luminosity at every timestamp. The aim of this project is to make a tracking system with a user-friendly interface that can be used to track the route taken by the vehicle and ambience like temperature and light conditions so the owner need not worry about the illicit use of their vehicle.	+	* Use Raspberry Pi 3 to work as a TCP server to receive data from client
		+	* Create a database to keep a record of previously acquired data
		+
		+	4) Set up Webserver:
		+	* Start the web server and host a web page
		+
	=== Team Members & Responsibilities ===		=== Team Members & Responsibilities ===
−	*  Ankit Gandhi	+	'''Ankit Gandhi'''
−	** Rasberry Pi environment setup, Hardware support	+
−	*  Bharat Khanna	+	--> Software Architecture, Raspberry Pi setup, ESP8266 firmware development
−	**  Interface ESP8266 with ARM microcontroller, Hardware support	+
−	*  Sujeeth Emmadi	+	'''Bharat Khanna'''
−	**	+
−	* Veena Manasa Kanakamalla	+	--> Device driver development for SIM808/ESP8266 for ARM microcontroller, PCB designing
−	**	+
		+	'''Sujeeth Emmadi'''
		+
		+	--> Software Architecture, Wiki Report, PHP web server
		+
		+	'''Veena Manasa Kanakamalla'''
		+
		+	--> Wiki Report, Sensor interface, Hardware Support
	== Schedule ==		== Schedule ==
−	This section of the report provides the team schedule for the Assembly line project, indicating the milestones to be achieved during the course of the project.
	{| class="wikitable"		{| class="wikitable"
Line 49:		Line 57:
	*Parts and components identification and ordering		*Parts and components identification and ordering
	| Completed		| Completed
−	|	+	| 03/27/2016
	|-		|-
	! scope="row"| 2		! scope="row"| 2
Line 57:		Line 65:
	*Design of Software Architecture(Flow diagram)		*Design of Software Architecture(Flow diagram)
	| Completed		| Completed
−	|	+	| 04/03/2016
	|-		|-
	! scope="row"| 3		! scope="row"| 3
Line 63:		Line 71:
	| 04/10/2016		| 04/10/2016
	|		|
−	*Firmware Development for I2C(Temperature Sensor) and GPS	+	*Device deiver development for I2C(Temperature Sensor) and UART(GPS) communication protocol
	*Testing of individual module		*Testing of individual module
	| Completed		| Completed
−	|	+	| 04/10/2016
	|-		|-
	! scope="row"| 4		! scope="row"| 4
Line 72:		Line 80:
	| 04/17/2016		| 04/17/2016
	|		|
−	*Wifi firmware development on LPC	+	*Device Driver development for ESP8266(Wi-Fi module) on ARM microcontroller
	| Completed		| Completed
−	|	+	| 04/20/2016
	|-		|-
	! scope="row"| 5		! scope="row"| 5
Line 80:		Line 88:
	| 04/24/2016		| 04/24/2016
	|		|
−	*Wifi Application development on Raspberry PI	+	*Socket programming on server(Raspberry Pi) to communicate between microcontroller and server.
	| Completed		| Completed
−	|	+	| 04/24/2016
	|-		|-
	! scope="row"| 6		! scope="row"| 6
Line 90:		Line 98:
	*Webserver development on Raspberry PI		*Webserver development on Raspberry PI
	| Completed		| Completed
−	|	+	| 05/01/2016
	|-		|-
	! scope="row"| 7		! scope="row"| 7
Line 96:		Line 104:
	| 05/08/2016		| 05/08/2016
	|		|
−	*Integration of all modules, Testing and debugging of the system	+	*Integration of all modules
	| Completed		| Completed
−	|	+	| 05/08/2016
	|-		|-
	! scope="row"| 8		! scope="row"| 8
Line 104:		Line 112:
	| 05/15/2016		| 05/15/2016
	|		|
−	*Final testing and Documentation	+	*Testing and debugging
−	| In Progress	+	| Completed
−	|	+	| 05/20/2016
	|-		|-
	|-		|-
Line 113:		Line 121:
	| 05/22/2016		| 05/22/2016
	|		|
−	*Final testing and Wiki Report	+	* Report writting
−	| In Progress	+	| Completed
−	|	+	| 05/23/2016
	|-		|-
	|}		|}
Line 161:		Line 169:
	== Design & Implementation ==		== Design & Implementation ==
−	The design section can go over your hardware and software design. Organize this section using sub-sections that go over your design and implementation.	+
−	<u> ''' Block Diagram ''' </u>	+	=== System Block Diagram ===
−	[[File:Block.png|center|400px|caption]]	+	----
		+	[[File:Cmpe244 warriors blockdiagram.jpg|center|500px|border]]
		+
		+	===Components===
		+	----
		+	==== SJOne Board ====
		+	----
		+	[[File:Cmpe244_warriors_sjone_board.jpg‎|left|200px|thumb|SJOne board]]
		+
		+
		+
		+	*Powered by ARM Cortex-M3
		+	*On board Temperature Sensor and light sensor.
		+	*Many GPIOs with two SPI, Multiple UARTs, and I2C availability.
		+	*Power from USB or External Power.
		+
		+
		+	The SJOne board offers whole lot of features out of which the temperature sensor, light intensity sensor and UART interfaces are utilized for the project.
		+
		+	==== The WiFi Module - ESP8266 ====
		+	----
		+	[[File:Cmpe244 warriors esp8266.jpg ‎|right|200px|thumb|ESP8266]]
		+
		+
		+	The features of ESP8266 are:
		+
		+	*1 x Analog input (1.8V max)
		+	*9 x GPIO (3.3V logic), which can also be used for I2C or SPI
		+	*2 x UART pins
		+	*2 x 3-12V power inputs, reset, enable, LDO-disable, 3.3V output
−	Hardware design for GPS, LSM303 ans ESP8266 interface.
−	<u> ''' peripheral interface board design ''' </u>
−	[[File:peripheral interface board design.png|center|400px|caption]]
		+	We have used UART for communication in our project.
−	<u> ''' Raspberry Pi ''' </u>	+	==== SIM808 GPS Module====
−	: Raspberry Pi is powered with Broadcom BCM2837 1.2GHz 64-bit quad-core ARMv8 processor.	+	----
−	: Integrated 802.11n wireless LAN	+	[[File:Sim808.jpg ‎|left|200px|thumb|SIM808]]
−	:
−	: Raspberry Pi is used as Web Server
−	<u> ''' SIM808 GPS/GSM Module ''' </u>
−	: Raspberry Pi is powered with Broadcom BCM2837 1.2GHz 64-bit quad-core ARMv8 processor.
−	: Integrated 802.11n wireless LAN
−	:
−	: Raspberry Pi is used as Web Server
−	<u> ''' ESP8266 Wifi Module ''' </u>	+	SIM 808 MiniGSM + GPS, an all-in-one cellular phone module which provides location-tracking, voice, text, SMS and data facilities
−	: Raspberry Pi is powered with Broadcom BCM2837 1.2GHz 64-bit quad-core ARMv8 processor.	+
−	: Integrated 802.11n wireless LAN	+	*  Quad-band 850/900/1800/1900MHz
−	:	+	*  AT command interface with "auto baud" detection
−	: Raspberry Pi is used as Web Server	+	*  22 tracking / 66 acquisition channels
		+	*  Sensitivity: Tracking: -165 dBm, Cold starts : -147 dBm
		+	*  Accuracy: approx 2.5 meters
		+
		+	==== Raspberry Pi 3 ====
		+	----
		+	[[File:Raspberry pi3.jpg ‎|right|200px|thumb|Raspberry Pi]]
		+
		+
		+	* A 1.2GHz 64-bit quad-core ARMv8 CPU with 1 GB RAM
		+	* On board 802.11n Wireless LAN
		+	* 40 GPIO pins and many serial interfaces
		+	* Micro SD card slot
		+	* On board chip antenna for radio
		+
		+
		+
		+	The Raspberry Pi 3 is the third generation Raspberry Pi. In this project raspberry pi is used as webserver.
	=== Hardware Interface ===		=== Hardware Interface ===
−	In this section, you can describe how your hardware communicates, such as which BUSes used. You can discuss your driver implementation here, such that the '''Software Design''' section is isolated to talk about high level workings rather than inner working of your project.	+	----
		+	The hardware design includes PCB designing using cadsoft Eagle(software for PCB board designing).  The circuit design of PCB includes SIM808(GSM/GPS module) and ESP826( Wi-Fi module) which is connected to ARM cortex-M3 microcontroller. Onboard sensors of SJOne board like TEMT6000X01(light sensor) and TMP102(temperature sensor) are also used to collect data. I2C, UART and TCP/IP are the three communication protocols that are being used in the project for establishing communication of temperature/light sensor, SIM808/ESP8266 & raspberry pi with ARM microcontroller respectively.
		+
		+	==== ESP8266 interface with SJOne ====
		+	----
		+	The WiFi module(ESP8266) is interfaced with the SJOne board(ARM microcontroller) using UART3 bus. Pin number '''p4.28''' and '''p4.29''' is used as RX and TX respectively.
		+
		+	==== SIM808 GPS Module Interface with SJOne ====
		+	----
		+	The SIM808 module is interfaced with SJOne using UART protocol. The Transmit and Receive pins of the GPS module are connected to UART2 of SJOne. RX pin of GPS is connected to pin '''P2.8''' of SJOne board (TX) and TX pin of GPS is connected to pin '''P2.9''' of SJOne (RX).
−	=== Software Design ===	+	=== Software Design & Implementation  ===
−	Show your software design. For example, if you are designing an MP3 Player, show the tasks that you are using, and what they are doing at a high level. Do not show the details of the code. For example, do not show exact code, but you may show psuedocode and fragments of code.  Keep in mind that you are showing DESIGN of your software, not the inner workings of it.	+	----
		+	: System consists of two entities. A client and a server.
		+	[[File:cmpr244_warriors_flowchart.png|400pk|border|center|Flowchart]]
		+	==== Client ====
		+	----
−	=== Implementation ===	+	On the Client side, SJOne(ARM Cortex-M3) is interfaced with the sensors(temperature, light, latitude, longitude, time etc). It collects the data from sensors at regular interval and sends the received data to the server over WiFi.
−	This section includes implementation, but again, not the details, just the high level.  For example, you can list the steps it takes to communicate over a sensor, or the steps needed to write a page of memory onto SPI Flash.  You can include sub-sections for each of your component implementation.
−	== Testing & Technical Challenges ==	+	The client software is written on FreeRTOS using C/C++, including features of real-time embedded system, which is implemented using two tasks.
−	Describe the challenges of your project.	+
−	*First and very important aspect for any project is requirement gathering.	+	'''sensorTask'''
−	Make a smooth transition to testing section and described what it took to test your project.
−	Include sub-sections that list out a problem and solution, such as:	+	:This task takes sensor readings at regular intervals (3 milliseconds) (light, temperature, time, latitude, longitude, and time) and stores in a structure
		+	:And then calls the semaphoregive API which signals the higher priority WiFi task.
−	=== My Issue #1 LPC17xx UART Rx FIFO ===	+
−	:''' LPC17xx UART not able to receive more than 16 bytes'''	+	'''wifitask (Higher priority task than sensor task)'''
−	:'''Resolution ''':	+
−	:: Inside the interrupt reading as much data as available	+	:In the initialization it configures the ESP8266 for WiFi communication and connects to a predefined WiFi network and the server.
		+	:Then it waits for the semaphore from sensor task. Once signaled by sensor task, sends the data to the server.
		+
		+
		+
		+	'''Pseudo code for client'''
		+	<pre>
		+	sensorTask() {
		+	:readSensorData();
		+	:xSemaphoreGive();
		+	:delay();
		+	}</pre>
		+
		+	<pre>wifiTask() {
		+	:xSemaphoreTake();
		+	:sendData();
		+	}</pre>
		+
		+	<pre>main() {
		+	:xSemaphoreCreateBinary();
		+	:addtask(sensorTask, medium_priority);
		+	:addtask(wifiTask, high_priority);
		+	:start_scheduler();
		+	}</pre>
		+
		+	==== Server ====
		+	----
		+	Raspberry pi is used as TCP and web server. TCP server listens for client connection request, once connected, the server reads the data and stores it into MySQL database. Then web server reads the latest sensor values from the database and displays on the web page and plots the latitude and longitude using google maps.
		+
		+	Environmet setup requires installation of '''apache''', '''mysql''' and '''php''' on the board.
		+
		+	These commands can be used for installation
		+
		+	<pre>
		+	:sudo apt-get install apache2 -y
		+	:sudo apt-get install php5 libapache2-mod-php5 -y
		+	:sudo apt-get install php5-mysql
		+	</pre>
		+
		+	For Wifi network setup
		+
		+	pi@raspberrypi: sudo vim /etc/wpa_supplicant/wpa_supplicant.conf
		+
		+	And then put your ssid and password as follows
		+
		+	<pre>network={
		+	:ssid="your_ssid"
		+	:psk="password"
		+	}</pre>
		+
		+
		+	''' There are two modules on server side '''
		+
		+	''' TCP server'''
		+
		+	: TCP server connects to TCP client, receives the data and stores into the database.
		+	: It is written in C. It uses TCP socket to accept client requests and receive the sensor data.
		+
		+	''' Web server'''
		+	: Web server reads data from database and display on the web page. It is written in PHP.
		+	: Google maps APIs are used latitude,longitude plotting.
		+
		+	'''Pseudo code for TCP server'''
		+
		+	<pre>main() {
		+	:createsocket(socket);
		+	:bind(socket);
		+	:listen(socket);
		+	:accept(socket);
		+	:readData(socket);
		+	:insertDataMysqlDatabase();
		+	}</pre>
		+
		+	== Testing & Technical Challenges ==
		+	* First and very important step in any project is requirement gathering.
		+	* A good amount of time should be spent on Software and Hardware design. Once the on paper design is ready it makes the development phase very smooth.
		+	* Once the development is done testing (individual and as a whole system ) also very important.
		+	* Wifi client module can be tested usb to serial cable with PC. From PC terminal we can give the AT commands and check the responses. Further testing requires a TCP server, which can respond to the requests. This can be implemented using Hercules utility.
		+	* GPS module can also be tested in the same manner using  usb to serial cable with PC. From PC terminal we can give the AT commands and check the responses.
		+	* From client side GET/POST query can be used which will eliminate the requirement of TCP server.
		+
		+	===  '''Issues'''    ===
		+
		+	# '''LPC17xx UART Rx FIFO '''
		+	: LPC17xx UART not able to receive more than 16 bytes
		+	:Resolution :
		+	:: Used interrupt to solve this problem.
	== Conclusion ==		== Conclusion ==
−	Conclude your project here. You can recap your testing and problems.  You should address the "so what" part here to indicate what you ultimately learnt from this project. How has this project increased your knowledge?	+	Facing issues such as UART FIFO size and power requirements, allowed us to understand that our knowledge over several aspects, when it came to depth, was lacking. Solving these problems, helped us understand those concepts better but, more importantly, we gained experience on how to approach situations where the project gets stuck.
		+
		+	The concepts that we have worked on, and now understand better, in this project are:
		+	* Setting up TCP server-clients
		+	* Interfacing sensors using UART
		+	* Configuration of Interrupts
		+	* Understanding WiFi technology
		+	* Making use of AT commands
		+	* Socket Programming
	=== Project Video ===		=== Project Video ===
−	Upload a video of your project and post the link here.	+	[https://www.youtube.com/watch?v=ILiFeN9xiJ8| Project video]
	=== Project Source Code ===		=== Project Source Code ===
−	*  [https://sourceforge.net/projects/sjsu/files/CmpE_S2016/ Sourceforge Source Code Link]	+	Visit this link [https://sourceforge.net/projects/wifi-sensor-system/files/?source=navbar Sourceforge]
	== References ==		== References ==
−	=== Acknowledgement ===
−	Any acknowledgement that you may wish to provide can be included here.
−
−	=== References Used ===
−	List any references used in project.
−	=== Appendix ===	+	* [https://cdn-shop.adafruit.com/datasheets/SIM808_Hardware+Design_V1.00.pdf Adafruit-SIM808]
−	You can list the references you used.	+	* [https://cdn-learn.adafruit.com/downloads/pdf/adafruit-huzzah-esp8266-breakout.pdf Adafruit-ESP8266]
		+	* [https://github.com/adafruit/Adafruit_ESP8266 Adafruit_ESP8266_Github]
		+	* [https://github.com/adafruit/Adafruit_FONA Adafruit_SIM808_Github]

---

Latest revision as of 23:25, 24 May 2016

Wifi based sensor system

This is an IoT based sensor system which allows sensor data to be accessed over the internet from anywhere.

Abstract

The most basic aspect of an IoT system is the network of devices/objects. IoT allows objects to be sensed and controlled remotely across existing network infrastructure. This project is based on the same fundamental. SJOne board senses temperature, light intensity, and GPS (SIM800) module. WiFi capability is added to SJOne board using ESP8266 serial module. SJOne(client) transmits the sensor data over the network to the server. Raspberry Pi 3 acts as a server, receives the data from the client and stores it in mysql database. A php webpage takes the most recent entry from database and displays on the webpage along with map.

Objectives

1) Set up sensor hub:

• Interface GPS module with SJOne
• Write drivers to access the temperature and light intensity sensors on-board SJOne

2) Set up TCP Client:

• Interface the WiFi module with SJOne board and implement a TCP client
• Write device driver to transmit data from SJOne client to the server

3) Set up TCP Server:

• Use Raspberry Pi 3 to work as a TCP server to receive data from client
• Create a database to keep a record of previously acquired data

4) Set up Webserver:

• Start the web server and host a web page

Team Members & Responsibilities

Ankit Gandhi

--> Software Architecture, Raspberry Pi setup, ESP8266 firmware development

Bharat Khanna

--> Device driver development for SIM808/ESP8266 for ARM microcontroller, PCB designing

Sujeeth Emmadi

--> Software Architecture, Wiki Report, PHP web server

Veena Manasa Kanakamalla

--> Wiki Report, Sensor interface, Hardware Support

Schedule

SI No.	Start Date	End Date	Task	Status	Actual Completion Date
1	03/21/2016	03/27/2016	System design and High level Block diagram Parts and components identification and ordering	Completed	03/27/2016
2	03/28/2016	04/03/2016	Design of Software Architecture(Flow diagram)	Completed	04/03/2016
3	04/04/2016	04/10/2016	Device deiver development for I2C(Temperature Sensor) and UART(GPS) communication protocol Testing of individual module	Completed	04/10/2016
4	04/11/2016	04/17/2016	Device Driver development for ESP8266(Wi-Fi module) on ARM microcontroller	Completed	04/20/2016
5	04/18/2016	04/24/2016	Socket programming on server(Raspberry Pi) to communicate between microcontroller and server.	Completed	04/24/2016
6	04/25/2016	05/01/2016	Webserver development on Raspberry PI	Completed	05/01/2016
7	05/02/2016	05/08/2016	Integration of all modules	Completed	05/08/2016
8	05/09/2016	05/15/2016	Testing and debugging	Completed	05/20/2016
8	05/16/2016	05/22/2016	Report writting	Completed	05/23/2016

Parts List & Cost

Item#	Part Description	Vendor	Qty	Cost
1	Raspberry Pi	Adafruit	1	$39.95
2	ESP8266-Wifi Module	Adafruit	1	$9.95
3	SIM808 GPS/GSM Module	Adafruit	1	$49.95
4	Passive GPS Antenna uFL	Adafruit	1	$3.95
5	USB to TTL Serial Cable	Adafruit	1	$9.95

Design & Implementation

System Block Diagram

---

Components

---

SJOne Board

---

• Powered by ARM Cortex-M3
• On board Temperature Sensor and light sensor.
• Many GPIOs with two SPI, Multiple UARTs, and I2C availability.
• Power from USB or External Power.

The SJOne board offers whole lot of features out of which the temperature sensor, light intensity sensor and UART interfaces are utilized for the project.

The WiFi Module - ESP8266

---

The features of ESP8266 are:

• 1 x Analog input (1.8V max)
• 9 x GPIO (3.3V logic), which can also be used for I2C or SPI
• 2 x UART pins
• 2 x 3-12V power inputs, reset, enable, LDO-disable, 3.3V output

We have used UART for communication in our project.

SIM808 GPS Module

---

SIM 808 MiniGSM + GPS, an all-in-one cellular phone module which provides location-tracking, voice, text, SMS and data facilities

• Quad-band 850/900/1800/1900MHz
• AT command interface with "auto baud" detection
• 22 tracking / 66 acquisition channels
• Sensitivity: Tracking: -165 dBm, Cold starts : -147 dBm
• Accuracy: approx 2.5 meters

Raspberry Pi 3

---

• A 1.2GHz 64-bit quad-core ARMv8 CPU with 1 GB RAM
• On board 802.11n Wireless LAN
• 40 GPIO pins and many serial interfaces
• Micro SD card slot
• On board chip antenna for radio

The Raspberry Pi 3 is the third generation Raspberry Pi. In this project raspberry pi is used as webserver.

Hardware Interface

---

The hardware design includes PCB designing using cadsoft Eagle(software for PCB board designing). The circuit design of PCB includes SIM808(GSM/GPS module) and ESP826( Wi-Fi module) which is connected to ARM cortex-M3 microcontroller. Onboard sensors of SJOne board like TEMT6000X01(light sensor) and TMP102(temperature sensor) are also used to collect data. I2C, UART and TCP/IP are the three communication protocols that are being used in the project for establishing communication of temperature/light sensor, SIM808/ESP8266 & raspberry pi with ARM microcontroller respectively.

ESP8266 interface with SJOne

---

The WiFi module(ESP8266) is interfaced with the SJOne board(ARM microcontroller) using UART3 bus. Pin number p4.28 and p4.29 is used as RX and TX respectively.

SIM808 GPS Module Interface with SJOne

---

The SIM808 module is interfaced with SJOne using UART protocol. The Transmit and Receive pins of the GPS module are connected to UART2 of SJOne. RX pin of GPS is connected to pin P2.8 of SJOne board (TX) and TX pin of GPS is connected to pin P2.9 of SJOne (RX).

Software Design & Implementation

---

System consists of two entities. A client and a server.

Client

---

On the Client side, SJOne(ARM Cortex-M3) is interfaced with the sensors(temperature, light, latitude, longitude, time etc). It collects the data from sensors at regular interval and sends the received data to the server over WiFi.

The client software is written on FreeRTOS using C/C++, including features of real-time embedded system, which is implemented using two tasks.

sensorTask

This task takes sensor readings at regular intervals (3 milliseconds) (light, temperature, time, latitude, longitude, and time) and stores in a structure

And then calls the semaphoregive API which signals the higher priority WiFi task.

wifitask (Higher priority task than sensor task)

In the initialization it configures the ESP8266 for WiFi communication and connects to a predefined WiFi network and the server.

Then it waits for the semaphore from sensor task. Once signaled by sensor task, sends the data to the server.

Pseudo code for client

sensorTask() {
:readSensorData();
:xSemaphoreGive();
:delay(); 
}

wifiTask() {
:xSemaphoreTake();
:sendData();
}

main() {
:xSemaphoreCreateBinary();
:addtask(sensorTask, medium_priority);
:addtask(wifiTask, high_priority);
:start_scheduler();
}

Server

---

Raspberry pi is used as TCP and web server. TCP server listens for client connection request, once connected, the server reads the data and stores it into MySQL database. Then web server reads the latest sensor values from the database and displays on the web page and plots the latitude and longitude using google maps.

Environmet setup requires installation of apache, mysql and php on the board.

These commands can be used for installation

:sudo apt-get install apache2 -y
:sudo apt-get install php5 libapache2-mod-php5 -y
:sudo apt-get install php5-mysql

For Wifi network setup

pi@raspberrypi: sudo vim /etc/wpa_supplicant/wpa_supplicant.conf

And then put your ssid and password as follows

network={
:ssid="your_ssid"
:psk="password" 
}

There are two modules on server side

TCP server

TCP server connects to TCP client, receives the data and stores into the database.

It is written in C. It uses TCP socket to accept client requests and receive the sensor data.

Web server

Web server reads data from database and display on the web page. It is written in PHP.

Google maps APIs are used latitude,longitude plotting.

Pseudo code for TCP server

main() {
:createsocket(socket);
:bind(socket);
:listen(socket);
:accept(socket);
:readData(socket);
:insertDataMysqlDatabase();
}

Testing & Technical Challenges

• First and very important step in any project is requirement gathering.
• A good amount of time should be spent on Software and Hardware design. Once the on paper design is ready it makes the development phase very smooth.
• Once the development is done testing (individual and as a whole system ) also very important.
• Wifi client module can be tested usb to serial cable with PC. From PC terminal we can give the AT commands and check the responses. Further testing requires a TCP server, which can respond to the requests. This can be implemented using Hercules utility.
• GPS module can also be tested in the same manner using usb to serial cable with PC. From PC terminal we can give the AT commands and check the responses.
• From client side GET/POST query can be used which will eliminate the requirement of TCP server.

Issues

1. LPC17xx UART Rx FIFO

LPC17xx UART not able to receive more than 16 bytes

Resolution :

Used interrupt to solve this problem.

Conclusion

Facing issues such as UART FIFO size and power requirements, allowed us to understand that our knowledge over several aspects, when it came to depth, was lacking. Solving these problems, helped us understand those concepts better but, more importantly, we gained experience on how to approach situations where the project gets stuck.

The concepts that we have worked on, and now understand better, in this project are:

• Setting up TCP server-clients
• Interfacing sensors using UART
• Configuration of Interrupts
• Understanding WiFi technology
• Making use of AT commands
• Socket Programming

Project Video

Project video

Project Source Code

Visit this link Sourceforge

References

• Adafruit-SIM808
• Adafruit-ESP8266
• Adafruit_ESP8266_Github
• Adafruit_SIM808_Github