Accident security Using GPS
In this project we will make project which will be fixed in Car. In case of any accident the our GSM modem will send sms on stored no. about the location via GPS reading.
GPS SYSTEM will give information about the location. We will use 89s52 for rxing data from GPS. A serial IC MAX 232 will be used to interface GPS with 89s52.
We will use 16*2 LCD to show all data reading from GPS receiver.
LCD will get data Microcntroller and will show North south coordinates and angle with respect to nearest satellite.
We will interface LCD at port 0 of 89s52. Rs , rw and en pins will be connected at port 2
Whole project divides into following parts
- Power supply- 5v and 9v power supply will be used for microcontroller and GM moidem circuit
- LCD interface- GPS rxed coordinates will be displayed on LCD
- Microcontroller- 89s51 or 89s52 will be used to get data from gps and totransfer data serially.
- GPS interface- it will work at 9600 baud rate
- GSM modem interface- we will use Toshan SM300 GSM modem working at 4800 baud rate
- Serial Interface- max 232 interface will be used.
The Global Positioning System (GPS) is a space-based global navigation satellite system that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. It is maintained by the United States government and is freely accessible by anyone with a GPS receiver.
The output is serial data of 9600 baud rate which is standard NMEA 0183 v3.0 protocol offering
industry standard data messages and a command set for easy interface to mapping software and
Features of GPS receiver
- High sensitivity -160dBm
- Searching up to 65 Channel of satellites
- LED indicating data output
- Low power consumption
- GPS L1 C/A Code
- Supports NMEA0183 V 3.01 data protocol
- Real time navigation for location based services
- Works from +5V DC signal and outputs 9600 bps serial data
- Magnetic base active antenna with 3 meter wire length for vehicle rooftop installation
|Item||Qty.||Cost in rs.||ID|
|mcU 89s51||1||60||IC 89C2051|
|IC BASE||1||10||20 PIN|
|LEDS||5||2||RED 15 MM|
|MICRO SWITCHES||2||1||PUSH TO ON|
WELCOME TO THE WORLD OF THE MICROCONTROLLERS.
Look around. Notice the smart “intelligent” systems? Be it the T.V, washing machines, video games, telephones, automobiles, aero planes, power systems, or any application having a LED or a LCD as a user interface, the control is likely to be in the hands of a micro controller!
Measure and control, that’s where the micro controller is at its best.
Micro controllers are here to stay. Going by the current trend, it is obvious that micro controllers will be playing bigger and bigger roles in the different activities of our lives.
So where does this scenario leave us? Think about it……
The world of Micro controllers
What is the primary difference between a microprocessor and a micro controller? Unlike the microprocessor, the micro controller can be considered to be a true “Computer on a chip”.
In addition to the various features like the ALU, PC, SP and registers found on a microprocessor, the micro controller also incorporates features like the ROM, RAM, Ports, timers, clock circuits, counters, reset functions etc.
While the microprocessor is more a general-purpose device, used for read, write and calculations on data, the micro controller, in addition to the above functions also controls the environment.
We have used a whole lot of technical terms already! Don’t get worried about the meanings at this point. We shall understand these terms as we proceed further
For now just be aware of the fact, that all these terms literally mean what they say.
Bits and Bytes
Before starting on the 8051, here is a quick run through on the bits and bytes. The basic unit of data for a computer is a bit. Four bits make a nibble. Eight bits or two nibbles make a byte. Sixteen bits or four nibbles or two bytes make a word.
1024 bytes make a kilobyte or 1KB, and 1024 KB make a Mega Byte or 1MB.
Thus when we talk of an 8-bit register, we mean the register is capable of holding data of 8 bits only.
The 8051 developed and launched in the early 80`s, is one of the most popular micro controller in use today. It has a reasonably large amount of built in ROM and RAM. In addition it has the ability to access external memory.
The generic term `8×51` is used to define the device. The value of x defining the kind of ROM, i.e. x=0, indicates none, x=3, indicates mask ROM, x=7, indicates EPROM and x=9 indicates EEPROM or Flash.
A note on ROM
The early 8051, namely the 8031 was designed without any ROM. This device could run only with external memory connected to it. Subsequent developments lead to the development of the PROM or the programmable ROM. This type had the disadvantage of being highly unreliable.
The next in line, was the EPROM or Erasable Programmable ROM. These devices used ultraviolet light erasable memory cells. Thus a program could be loaded, tested and erased using ultra violet rays. A new program could then be loaded again.
An improved EPROM was the EEPROM or the electrically erasable PROM. This does not require ultra violet rays, and memory can be cleared using circuits within the chip itself.
Finally there is the FLASH, which is an improvement over the EEPROM. While the terms EEPROM and flash are sometimes used interchangeably, the difference lies in the fact that flash erases the complete memory at one stroke, and not act on the individual cells. This results in reducing the time for erasure.
Understanding the basic features of the 8051 core
Let’s now move on to a practical example. We shall work on a simple practical application and using the example as a base, shall explore the various features of the 8051 microcontroller.
The positive side (+ve) of the battery is connected to one side of a switch. The other side of the switch is connected to a bulb or LED (Light Emitting Diode). The bulb is then connected to a resistor, and the other end of the resistor is connected to the negative (-ve) side of the battery.
When the switch is closed or ‘switched on’ the bulb glows. When the switch is open or ‘switched off’ the bulb goes off
If you are instructed to put the switch on and off every 30 seconds, how would you do it? Obviously you would keep looking at your watch and every time the second hand crosses 30 seconds you would keep turning the switch on and off.
Imagine if you had to do this action consistently for a full day. Do you think you would be able to do it? Now if you had to do this for a month, a year??
No way, you would say!
The next step would be, then to make it automatic. This is where we use the Microcontroller.
But if the action has to take place every 30 seconds, how will the microcontroller keep track of time?
Look at the following instruction,
These are the motors that are commonly found in the toys and the tape recorders. These motors change the direction of rotation by changing the polarity. Most chips can’t pass enough current or voltage to spin a motor. Also, motors tend to be electrically noisy (spikes) and can slam power back into the control lines when the motor direction or speed is changed.
Specialized circuits (motor drivers) have been developed to supply motors with power and to isolate the other ICs from electrical problems. These circuits can be designed such that they can be completely separate boards, reusable from project to project.
A very popular circuit for driving DC motors (ordinary or gearhead) is called an H-bridge. It’s called that because it looks like the capital letter ‘H’ on classic schematics. The great ability of an H-bridge circuit is that the motor can be driven forward or backward at any speed, optionally using a completely independent power source.
The H-Bridge Circuit
This circuit known as the H-bridge (named for its topological similarity to the letter “H”) is commonly used to drive motors. In this circuit two of four transistors are selectively enabled to control current flow through a motor.
opposite pair of transistors (Transistor One and Transistor Three) is enabled, allowing current to flow through the motor. The other pair is disabled, and can be thought of as out of the circuit.
By determining which pair of transistors is enabled, current can be made to flow in either of the two directions through the motor. Because permanent-magnet motors reverse their direction of turn when the current flow is reversed, this circuit allows bidirectional control of the motor.
The H-Bridge with Enable Circuitry
It should be clear that one would never want to enable Transistors One and Two or Transistors Three and Four simultaneously. This would cause current to flow from Power + to Power – through the transistors, and not the motors, at the maximum current-handling capacity of either the power supply or the transistors. This usually results in failure of the H-Bridge. To prevent the possibility of this failure, enable circuitry as depicted in Figure is typically used.
In this circuit, the internal inverters ensure that the vertical pairs of transistors are never enabled simultaneously. The Enable input determines whether or not the whole circuit is operational. If this input is false, then none of the transistors are enabled, and the motor is free to coast to a stop.
By turning on the Enable input and controlling the two Direction inputs, the motor can be made to turn in either direction.
Note that if both direction inputs are the same state (either true or false) and the circuit is enabled, both terminals will be brought to the same voltage (Power + or Power – , respectively). This operation will actively brake the motor, due to a property of motors known as back emf, in which a motor that is turning generates a voltage counter to its rotation. When both terminals of the motor are brought to the same electrical potential, the back emf causes resistance to the motor’s rotation.
Stepper motors are special kind of heavy duty motors having 2 or 4 coils. The motors will be stepping each time when it get the pulse. As there are many coils in the motors we need to energize the coils in a specific sequence for the rotation of the motor. These motors are mostly used in heavy machines. The figure shown below consists of a 4 coil stepper motor and the arrow mark will rotate when the coils are energized in the sequence.
Unlike DC motors stepper motors can be turned accurately for the given degrees.
Servo motors unlike the stepper motor it has to be controlled by the timing signal. This motor has only one coil. It is mostly used in robots for its lightweight and low power consumption. The servo motors can also be accurately rotated by the making the control signal of the servo motor high for a specific time period. Actually the servo motor will be having 3 wires where 2 are for power supply and another one is for the control signal. Driving the servomotors is so simple that you need to make the control signal high for the specific amount of time. The width of the pulse determines the output position of the shaft
|CIRCUIT AND THEORY ARRANGEMENT|
|CHECKING AVAILABILITY OF COMPONENTS|
|COMPONENT INSERTION AND SOLDERING|
|REWORK OR TROOUBLE SHOOTING|
Crystal 11.592 MHz- 1 nos.
On/off Switch- 1 nos.
Diodes IN 4001- 10 nos.
Optocoupler 817- 2nos.
Cap 10µf,0.1 µf,330µf
Transistors -547or 548
Resistances 330 Ω,8.2kΩ,30pf
IC7805 voltage Regulator
Infrared sensors set
Copper Clad board
GPS Working Details
GPS – NMEA sentence information
AVR Library for parsing GPS Data
Interface to GPS – Article
- Car Navigation and Marine Navigation, Fleet Management
- Automotive Navigator Tracking, Vehicle Tracking
- AVL and Location-Based Services
- Auto Pilot, Personal Navigation or touring devices
- Tracking devices/systems and Mapping devices application Emergency Locator
- Geographic Surveying
- Personal Positioning
- Sporting and Recreation
- Embedded applications which needs to be aware of its location on earth