A Road Traffic Accident (RTA) can be defined as, ‘An event that occurs on a way or street open to public traffic; resulting in one or more persons being injured or killed, where at least one moving vehicle is involved.
Thus RTA is a collision between vehicles; between vehicles and pedestrians; between vehicles and animals; or between vehicles and geographical or architectural obstacles.’ Road traffic accidents are a human tragedy. They involve high human suffering and socioeconomic costs in terms of premature deaths, injuries, loss of productivity, and so on.
During 2012, Road Traffic Injuries (RTI) ranked fourth among the leading causes of death in the world. Nearly 1.3 million people die every year on the world’s roads and 20 to 50 million people suffer non-fatal injuries, with many sustaining a disability as a result of their injury Road traffic injuries are the leading cause of death among young people aged 15-29 years and cost countries 1-3% of the gross domestic product (GDP).
The project aims at causing a decrease in such road accident fatalities by designing an efficient notification system which will enable us to provide immediate medical assistance to the victims of accidents.
1.2. AIMS AND OBJECTIVES
Security in travel is primary concern for everyone. This Project describes a design of effective alarm system that can monitor an automotive / vehicle / car condition in traveling. This project is designed to inform about an accident that is occurred to a vehicle to the family members of the traveling persons. This project uses a piezo-electric sensor which can detect the abrupt vibration when an accident is occurred. This sends a signal to microcontroller.
This Project presents an automatic vehicle accident detection system using GPS and GSM modems. The system can be interconnected with the car alarm system and alert the owner on his mobile phone. This detection and messaging system is composed of a GPS receiver, Microcontroller and a GSM Modem. GPS Receiver gets the location information from satellites in the form of latitude and longitude.
The Microcontroller processes this information and this processed information is sent to the user/owner using GSM modem A GSM modem is interfaced to the MCU. The GSM modem sends an SMS to the predefined mobile number and informs about this accident. This enable it to monitor the accident situations and it can immediately alerts the police/ambulance service with the location of accident.
The project is built around the AT89S52 micro controller from Atmel. This micro controller provides all the functionality of the SMS alert system. It also takes care of filtering of the signals at the inputs.
The uniqueness of this project is, not only alerting the neighbors by its siren, but also it sends a caution SMS to the predefined mobile numbers. This numbers can be changed at any time by the user using a 3X4 key pad. These numbers are stored in EEPROM.
This project uses regulated 5V, 750mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.
1.3 USEFULNESS OF PROJECT FOR USER
‘ The Accident Alert System aims to provide an efficient and cost-effective way to decrease the degradation in victim’s health post-accident.
‘ The GSM modem sends a distress message to the victim’s relative and the Trauma Centre whose numbers are already saved.
‘ The GPS System helps to track the site of accident and provide Immediate Medical Help to the victims.
‘ The Microcontroller processes this information and this processed information is sent to the user/owner using GSM modem A GSM modem is interfaced to the MCU.
‘ The GSM modem sends an SMS to the predefined mobile number and informs about this accident.
‘ This enable it to monitor the accident situations and it can immediately alerts the police/ambulance service with the location of accident.
CHAPER-2
LITERATURE REVIEW AND WORK PLAN
2.1 LITERATURE REVIEW
The first step to understand the different problems and their solution there is to find the different literature like different research papers, reference books and various patents available in the present time which helps to find out causes of the problems and their remedies. Literature review helps to find the solution and improve the current methods applied to solve the given problem.
RESEARCH PAPERS
The following is the list of patents analyzed before designing the Accident Alert System. It helped us to understand the interfacing of various components used in the project , such as GSM and GPS modems, and also the practical implementation of such projects in real life.
The analysis of these Research Papers helped to understand the current technologies prevalent in the field of accident notification system and to find better yet simpler alternatives to mordernise such notification systems.
The following table shows the list of Research Papers analysed alongwith the names of their Inventors , Applicants and Publication Number.
SR.NO
PATENT NAME
PUBLICATION
NUMBER
APPLICANT
INVENTORS
1 Systems and methods for localized wireless notification WO2011031961 A2 Qualcomm Incorporated
Kirk S. Taylor,
2 Emergency and traffic alert system EP2411971 A1 B&C Electronic Engineering, Inc.
Juan Gutierrez, Carl Johnson
3 CROSS TRAFFIC COLLISION ALERT SYSTEM Us 201 1/0133917 A1 GM Global Technology Operations LLC, Detroit, MI (US) ShuqingZeng, Sterling Heights, MI(U.S.)
4 HANDHELD PORTABLE AUTOMATIC EMERGENCY ALERT SYSTEM AND METHOD US 2005/0208925 A1 Texas Instruments Incorporated, Dallas’ TX (Us) Carl M. Panasik,TX(U.S.)
James F. Salzman,TX(U.S.)
5 WARNING LIGHT Rotalight Limited, Bristol, England Keith J. Pillinger; David S. Griffith,
both of Bristol, England
6 Automatic alert system for vehicles EP1054371 B1 Siemens
Aktiengesellschaft Dr.Hans-Wilhelm
R’?hl, RoekelJauke Van
7 Vehicle warning system with improved power
supply EP1763862 B1 PERSEN
TECHNOLOGIE
S INC FRANCZYK
FRANK, VANSTONE
JAMES
8 Vehicle collision detector and alert system US20040036587 A1 Derrick Howard
Jefferson Derrick Howard
Jefferson
9 Emergency vehicle alert system US7271736 B2 Michael Aaron
Siegel Michael Aaron
Siegel, Robert Yarbrough, William G.
Howell
10 Car collision global positioning system US20110291825 A1 KUWAIT
UNIVERSITY Ahmed Al-Sayegh
Table 2.1 Lists of Research Papers Analyzed
CONCLUSION FROM LITERATURE REVIEW
By analysis of above research papers and some other materials we get the idea about different components their usage, interfacing and designing. Designing should compact and can be easily connected with car components for hassle free and user friendly system.
2.2 WORK PLAN
CHAPTER 3
HARDWARE AND SOFTWARE DESCRIPTION
3.1 HARDWARE COMPONENTS
3.1.1 BLOCK DIAGRAM
Figure 3.1.1 Block Diagram of the Proposed System
3.1.2 POWER SUPPLY
The input to the circuit is applied from the regulated power supply. The a.c. input i.e., 230V from the mains supply is step down by the transformer to 12V and is fed to a rectifier. The output obtained from the rectifier is a pulsating d.c. voltage. So in order to get a pure d.c voltage, the output voltage from the rectifier is fed to a filter to remove any a.c components present even after rectification. Now, this voltage is given to a voltage regulator to obtain a pure constant dc voltage.
Figure 3.1.2 Block Diagram of the Power Supply
Transformer
Usually, DC voltages are required to operate various electronic equipment and these voltages are 5V, 9V or 12V. But these voltages cannot be obtained directly. Thus the a.c input available at the mains supply i.e., 230V is to be brought down to the required voltage level. This is done by a transformer. Thus, a step down transformer is employed to decrease the voltage to a required level.
Rectifier
The output from the transformer is fed to the rectifier. It converts A.C. into pulsating D.C. The rectifier may be a half wave or a full wave rectifier. In this project, a bridge rectifier is used because of its merits like good stability and full wave rectification.
Filter
Capacitive filter is used in this project. It removes the ripples from the output of rectifier and smoothens the D.C. Output received from this filter is constant until the mains voltage and load is maintained constant. However, if either of the two is varied, D.C. voltage received at this point changes. Therefore a regulator is applied at the output stage.
Voltage regulator
As the name itself implies, it regulates the input applied to it. A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. In this project, power supply of 5V and 12V are required. In order to obtain these voltage levels, 7805 voltage regulators are to be used. The first number 78 represents positive supply and the numbers 05, 12 represent the required output voltage levels.
3.1.3 GSM (Global System for Mobile)
Introduction
‘ Definition
‘ GSM History
‘ SIM900
‘ GSM Operation
‘ Advantages over analog system.
Definition
Global System for Mobile (GSM) is a second generation cellular standard developed to cater voice services and data delivery using digital modulation. GSM is a digital cellular communications system. It is used for transmitting mobile voice and data services. International roaming capability, Encryption capability for information security and privacy
Figure 3.1.3 GSM MODEM
GSM-History
‘ Developed by Group Special Mobile (founded 1982) which was an initiative of CEPT (Conference of European Post and Telecommunication)
‘ Aimed at replacing the incompatible analog system
‘ Presently the responsibility of GSM standardization resides with special mobile Group under ETSI (European telecommunication Standards Institute)
‘ Full set of specifications phase-I became available in 1990.
‘ Under ETSI, GSM is named as ‘Global System for Mobile communication ‘
‘ Today many providers all over the world use GSM (more than 135 countries in Asia, Africa, Europe, Australia, America) More than 1300 million subscribers in world and 45 million subscribers in India.
A GSM modem is a specialized type of modem which accepts a SIM card, and operates over a subscription to a mobile operator, just like a mobile phone. From the mobile operator perspective, a GSM modem looks just like a mobile phone. When a GSM modem is connected to a computer, this allows the computer to use the GSM modem to communicate over the mobile network. While these GSM modems are most frequently used to provide mobile internet connectivity, many of them can also be used for sending and receiving SMS and MMS messages
SIM900
Figure 3.1.3(A) SIM900
The SIM900 is a complete Quad-band GSM/GPRS solution in a SMT module which can be embedded in the customer applications. Featuring an industry-standard interface, the SIM900 delivers GSM/GPRS 850/900/1800/1900MHz performance for voice, SMS, Data, and Fax in a small form factor and with low power consumption. With a tiny configuration of 24mm x 24mm x 3 mm, SIM900 can fit almost all the space requirements in your M2M application, especially for slim and compact demand of design.
GENERAL FEATURES AND SPECIFICATIONS
‘ SIM900 is designed with a very powerful single-chip processor integrating AMR926EJ-S core
‘ Quad – band GSM/GPRS module with a size of 24mmx24mmx3mm
‘ SMT type suit for customer application
‘ An embedded Powerful TCP/IP protocol stack
‘ Based upon mature and field-proven platform, backed up by our support service, from definition to design and production
General features
‘ Quad-Band 850/ 900/ 1800/ 1900 MHz
‘ GPRS multi-slot class 10/8
‘ GPRS mobile station class B
‘ Class 4 (2 W @850/ 900 MHz)
‘ Class 1 (1 W @ 1800/1900MHz)
‘ Dimensions: 24* 24 * 3 mm
‘ Weight: 3.4g
‘ Control via AT commands
‘ SIM application toolkit
‘ Supply voltage range 3.4 -4.5 V
‘ Low power consumption
‘ Operation temperature: -30 ??C to +80 ??C
‘ GPRS class 10: max. 85.6 kbps (downlink)
GSM OPERATION
GSM Module is used for sending and receiving Short message Service (SMS). The flow chart representing the Message handling procedure is shown below.
Figure 3.1.3(B) SMS HANDLING FLOWCHART FOR GSM
Advantages of GSM over Analog system
‘ Capacity increases
‘ Reduced RF transmission power and longer battery life.
‘ International roaming capability.
‘ Better security against fraud (through terminal validation and user authentication).
‘ Encryption capability for information security and privacy.
‘ Compatibility with ISDN, leading to wider range of services
3.1.4 GPS (Global Positioning System)
The Global Positioning System (GPS) is a U.S. space-based global navigation satellite system. It provides reliable positioning, navigation, and timing services to worldwide users on a continuous basis in all weather, day and night, anywhere on or near the Earth which has an unobstructed view of four or more GPS satellites.
GPS is made up of three segments: Space, Control and User. The Space Segment is composed of 24 to 32 satellites in Medium Earth Orbit and also includes the boosters required to launch them into orbit.
The Control Segment is composed of a Master Control Station, an Alternate Master Control Station, and a host of dedicated and shared Ground Antennas and Monitor Stations. The User Segment is composed of hundreds of thousands of U.S. and allied military users of the secure GPS Precise Positioning Service and tens of millions of civil, commercial and scientific users of the Standard Positioning Service (see GPS navigation devices). GPS satellites broadcast signals from space that GPS receivers use to provide three-dimensional location (latitude, longitude, and altitude) plus precise time.
Figure 3.1.4 GPS MODEM
GPS has become a widely used aid to navigation worldwide, and a useful tool for map-making, land surveying, commerce, scientific uses, tracking and surveillance, and hobbies such as geocaching and way marking. Also, the precise time reference is used in many applications including the scientific study of earthquakes and as a time synchronization source for cellular network protocols.
GPS has become a mainstay of transportation systems worldwide, providing navigation for aviation, ground, and maritime operations. Disaster relief and emergency services depend upon GPS for location and timing capabilities in their life-saving missions. The accurate timing that GPS provides facilitates everyday activities such as banking, mobile phone operations, and even the control of power grids. Farmers, surveyors, geologists and countless others perform their work more efficiently, safely, economically, and accurately using the free and open GPS signals.
Basic concept of GPS
A GPS receiver calculates its position by precisely timing the signals sent by the GPS satellites high above the Earth. Each satellite continually transmits messages which include
‘ The time the message was transmitted
‘ Precise orbital information (the ephemeris)
‘ The general system health and rough orbits of all GPS satellites (the almanac).
The receiver utilizes the messages it receives to determine the transit time of each message and computes the distances to each satellite. These distances along with the satellites’ locations are used with the possible aid of trilateration to compute the position of the receiver. This position is then displayed, perhaps with a moving map display or latitude and longitude; elevation information may be included.
The GPS signal allows to repeat this calculation every 6 seconds. Many GPS units show derived information such as direction and speed, calculated from position changes.
Three satellites might seem enough to solve for position, since space has three dimensions and a position on the Earth’s surface can be assumed. However, even a very small clock error multiplied by the very large speed of light’the speed at which satellite signals propagate’results in a large positional error. Therefore receivers use four or more satellites to solve for the receiver’s location and time. The very accurately computed time is effectively hidden by most GPS applications, which use only the location. A few specialized GPS applications do however use the time; these include time transfer, traffic signal timing, and synchronization of cell phone base stations.
Figure 3.1.4(A) GPS Block II-F satellite in orbit
Figure 3.1.4(B) Civilian GPS receiver (“GPS navigation device”) in a marine application
Figure 3.1.4(C) Automotive navigation system in a taxicab
Applications
The Global Positioning System, while originally a military project is considered a dual-use technology, meaning it has significant applications for both the military and the civilian industry.
3.1.5 MICROCONTROLLER (AT89S52)
DESCRIPTION
The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the Industry standard 80C51 instruction set and pin out.
The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory pro-grammar. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.
The AT89S52 provides the following standard features: 8K bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes.
The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue functioning. The Power-down mode saves the RAM con-tents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset
FEATURES OF AT89S52
‘ Compatible with MCS??-51 Products ‘
‘ 8K Bytes of In-System Programmable (ISP) Flash Memory ‘ Endurance: 10,000 Write/Erase Cycles
‘ 4.0V to 5.5V Operating Range
‘ Fully Static Operation: 0 Hz to 33 MHz
‘ Three-level Program Memory Lock
‘ 256 x 8-bit Internal RAM
‘ 32 Programmable I/O Lines
‘ Three 16-bit Timer/Counters
‘ Eight Interrupt Sources
‘ Full Duplex UART Serial Channel
‘ Low-power Idle and Power-down Modes
‘ Interrupt Recovery from Power-down Mode
‘ Watchdog Timer
‘ Dual Data Pointer
‘ Power-off Flag
‘ Fast Programming Time
‘ Flexible ISP Programming (Byte and Page Mode)
‘ Green (Pb/Halide-free) Packaging Option
PIN DESCRIPTION
VCC
Supply voltage.
GND
Ground
Port 0
Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as high-impedance inputs.Port 0 can also be configured to be the multiplexed low-order address/data bus during accesses to external program and data memory. In this mode, P0 has internal pull-ups.Port 0 also receives the code bytes during Flash programming and outputs the code bytes during program verification. External pull-ups are required during program verification.
Port 1
Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups.In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX), respectively, as shown in the following .Port 1 also receives the low-order address bytes during Flash programming and verification
Port Pin Alternate Functions
P1.0 T2 (external count input to Timer/Counter 2), clock-out
P1.1 T2EX (Timer/Counter 2 capture/reload trigger and direction control)
P1.5 MOSI (used for In-System Programming)
P1.6 MISO (used for In-System Programming)
P1.7 SCK (used for In-System Programming)
Port 2
Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups.Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @ DPTR). In this application, Port 2 uses strong internal pull-ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register.Port 2 also receives the high-order address bits and some control signals during Flash programming and verification.
Port 3
Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 3 output buffers can
sink/source four TTL inputs. When 1s are written to Port 3 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pull-ups.
Port 3 receives some control signals for Flash programming and verification.
Port 3 also serves the functions of various special features of the AT89S52, as shown in the fol-
lowing .
Port Pin Alternate Functions
P3.0 RXD (serial input port)
P3.1 TXD (serial output port)
P3.2 INT0 (external interrupt 0)
P3.3 INT1 (external interrupt 1)
P3.4 T0 (timer 0 external input)
P3.5 T1 (timer 1 external input)
P3.6 WR (external data memory write strobe)
P3.7 RD (external data memory read strobe)
RST
Reset input. A high on this pin for two machine cycles while the oscillator is running resets the
device. This pin drives high for 98 oscillator periods after the Watchdog times out. The DISRTO
bit in SFR AUXR (address 8EH) can be used to disable this feature. In the default state of bit
DISRTO, the RESET HIGH out feature is enabled.
ALE/PROG
Address Latch Enable (ALE) is an output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming.
In normal operation, ALE is emitted at a constant rate of 1/6 the oscillator frequency and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external data memory.
If desired, ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode.
PSEN
Program Store Enable (PSEN) is the read strobe to external program memory.
When the AT89S52 is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.
EA/VPP
External Access Enable.EA must be strapped to GND in order to enable the device to fetch
Code from external program memory locations starting at 0000H up to FFFFH.Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset.
EA should be strapped to VCC for internal program executions.
This pin also receives the 12-volt programming enable voltage (VPP) during Flash programming.
XTAL1
Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
XTAL2
Output from the inverting oscillator amplifier.
3.1.6 RS232 CABLE
To allow compatibility among data communication equipment, an interfacing standard called RS232 is used. Since the standard was set long before the advent of the TTL logic family, its input and output voltage levels are not TTL compatible. For this reason, to connect any RS232 to a microcontroller system, voltage converters such as MAX232 are used to convert the TTL logic levels to the RS232 voltage levels and vice versa.
3.1.7 MAX232 IC
Max232 IC is a specialized circuit which makes standard voltages as required by RS232 standards. This IC provides best noise rejection and very reliable against discharges and short circuits. MAX232 IC chips are commonly referred to as line drivers. To ensure data transfer between PC and microcontroller, the baud rate and voltage levels of Microcontroller and PC should be the same. The voltage levels of microcontroller are logic1 and logic 0 i.e., logic 1 is +5V and logic 0 is 0V. But for PC, RS232 voltage levels are considered and they are: logic 1 is taken as -3V to -25V and logic 0 as +3V to +25V. So, in order to equal these voltage levels, MAX232 IC is used. Thus this IC converts RS232 voltage levels to microcontroller voltage levels and vice versa.
Figure 3.1.7 Pin diagram of MAX 232 IC
3.1.8 LIQUID CRYSTAL DISPLAY
LCD stands for Liquid Crystal Display. LCD is finding wide spread use replacing LEDs (seven segment LEDs or other multi segment LEDs) because of the following reasons:
‘ The declining prices of LCDs.
‘ The ability to display numbers, characters and graphics. This is in contrast to LEDs, which are limited to numbers and a few characters.
‘ Incorporation of a refreshing controller into the LCD, thereby relieving the CPU of the task of refreshing the LCD. In contrast, the LED must be refreshed by the CPU to keep displaying the data.
‘ Ease of programming for characters and graphics.
These components are ‘specialized’ for being used with the microcontrollers, which means that they cannot be activated by standard IC circuits. They are used for writing different messages on a miniature LCD.
Figure 3.1.8 LCD Display
We are using 20X4 LCD Display (4 lines, 20 characters). It has 16 pins(2 optional). It uses 8lines for parallel data plus 3 control signals, 2 connections to power, one more for contrast adjustment and two connections for LED back light. The reason for selection 20×4 lcd display is proper display of information and its status.
Table 3.1.8 Pin functions of LCD
3.1.9 LCD INTERFACING WITH MICROCONTROLLER
Figure 3.1.9 LCD INTERFACING WITH MICROCONTROLLER:
3.1.10 CERAMIC BUZZER
Figure 3.1.10 Ceramic Buzzer
A buzzer or beeper is an signaling device, which may be mechanical, electromechanical, or piezoelectric. Typical uses of buzzers and beepers include alarm devices, timers and confirmation of user input such as a mouse click or keystroke.
Piezoelectric buzzers generate sound through the bending vibrations of a thin metal plate adhered to a piezoelectric element. These buzzers feature a low power consumption, a safe, spark-free and non-contact structure, and a small size and light weight for an easy mounting to printed circuit boards. As a result, an increasing number of piezoelectric buzzers are now used to generate an artificial voice in combination with voice synthesizing ICs.
Key Specification
‘ Dimension: 12.0 x 7.5mm
‘ Rated voltage: 5.0V
‘ Frequency: 2,300Hz
3.1.11 VIBRATION DETECTOR
Figure 3.1.11 Vibration Sensor used in the project
Vibration sensor is a device which is used to sense the collision or impact. Vibration sensor converts the mechanical energy generated due to collision into electrical impulse. This electrical impulse activates the microcontroller and the concerned program starts to execute. Vibration sensor is a device which is used to sense the collision or impact. Vibration sensor converts the mechanical energy generated due to collision into electrical impulse. This electrical impulse activates the microcontroller and the concerned program starts to execute.
Vibration sensor consists of a magnet resting on as spring and copper coil wound all around it. In case of a collision the magnet starts moving due to spring action which generates a small emf according to Faraday’s Law. If this signal is greater than the threshold signal , the signal is passed on to other connected devices, else it is ignored. The sensitivity of the vibration sensor can be changed using a variable resistor.
By adding a sophisticated audio know-how to this manufacturing expertise, it offers a large array of electronic tone generating products, such as piezoceramic diaphragms, sounders and buzzers, to meet loud sound outputs, wide frequency ranges, and many other requirements.
We will be placing it at the bumper so that the magnitude of collision can be detected properly. The arrangement of this sensor in our project is as shown in the figure above which is sensed by the microcontroller. After sensing the signal the corresponding action is done by the microcontroller which is preprogrammed.
3.2 SOFTWARE DESCRIPTION
3.2.1 KEIL COMPILER
The Keil C51 C compiler for the microcontroller is used to solve the complex problems facing embedded software developers. It provides more features than any other 8051 C compiler available today. The microcontroller applications that are written in C and once complied using the C51 compiler have the efficiency and speed of the assembly language. While starting a new project, first we have to select the microcontroller, that we are going to use for our project from the device database and the ??Vision IDE sets all compiler, assembler, linker, and memory options.
The on-chip peripherals of the microcontroller are accurately simulated by the Keil ?? Vision debugger. The hardware configurations can be easily understand by the simulation and also avoids time wasting in setting up of problems. And also we can write and test the applications before the availability of the hardware
In-System debugger or USB-JTAG adapter can be used to download and test the program code on the target system. The C51compiler translates the C source files into re-locatable object modules which contains full symbolic information for debugging with micro vision debugger or an in-circuit emulator. This Keil C51 compiler generates fast compact codes for the 8051and its derivatives. It supports a number of C language extensions that have been added to support the microcontroller architecture like data types, pointers, memory types, Interrupts.
3.2.2 EMBEDDED C
Embedded C is not a part of the C language as such. Rather, it is a C language that is the subject of a technical report by the ISO working group named ‘Extensions for the Programming Language C to support Embedded Processors’.
It aims to provide portability and access to common performance-increasing features of processors used in domain of the DSP and embedded processing. The embedded C specification for fixed-point, named address spaces and name register gives the programmers direct access to the features in the target processor there by significantly improving the performance of the applications.
The hardware I/O extension is a portability feature of Embedded C. Its goal is to allow easy porting of device-driver code between systems. Embedded C is designed to bridge the performance mismatch between the Standard C and the embedded hardware and application architecture. It extends the C language with the primitives that are needed by signal processing applications and that are commonly provided by the DSP processors.
Embedded C makes life easier for application programmers. The primitives provided are the primitives that fit the conceptual model of the application which brings back the roots of C to the embedded systems as primarily a high-level language means of accessing the processor.
CHAPTER 4
RESULTS
4.1 EXPECTED OUTCOME
The Accident Alert System is aims at providing an excellent notification system in case of accidents and emergencies. The project targets to bring a fall in the number of accident fatalities around the world. A large number of fatalities occur in such cases due to late access to medical help and first aid. This scenario can be changed by the use of an efficient notification system.
In case of occurrence of an accident, the vibration sensor will detect the collision and send the signal to the microcontroller. The microcontroller acknowledges the signal and starts the execution of the delay program. If the accident isn’t bad enough, then the driver can press a button and stop further activities of the circuit.
If the button is not pressed within the next 2 minutes then a signal will be sent to the GSM modem from the microcontroller via MAX-232 IC. The GSM modem will send an accident notification message will be sent to the predefined numbers in the system along with the information about location of the accident.
As one of the numbers will be of the medical emergency number, like 108 in certain states of India, the medical help can easily be provided quickly to the victims and hence there will be a decrease in number of deaths as timely medical assistance can be provided. Also if the other number/s is of the relatives then even they will get notified about the accident and reach the victims.
4.2 IMAGES OF PROJECTS
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CHAPTER 5
CONCLUSION AND FUTURE WORK
5.1 DISCUSSION
Advantages
‘ Sophisticated security
‘ Monitors all hazards and threats
‘ Alert message to mobile phone for remote information
Applications
‘ Automotives and transport vehicles
‘ Security, Remote monitoring, Transportation and logistics
‘ This system is also can be interfaced with Vehicle airbag system.
5.2 FUTURE ADVANCEMENTS
‘ The Accident Alert System is a versatile system which can be modified to work with many other embedded circuits in vehicles to provide a number of applications.
‘ The Accident Alert System can be interfaced with the Air Bag system, which provides security to the driver in case of an accident.
‘ The circuit can be used for parking assistance in vehicles with slight modifications.
‘ A Proximity sensor can be added to the circuit, which would alert the driver by beeping a buzzer if the driver is about to collide with the vehicle in front.
‘ The presence of GSM modem makes it possible to track the vehicle in case of theft.
‘ The GPS modem makes it possible to make route navigation possible.
‘ A warning light or a loud horn can be interfaced with the circuit which is turned on in case of an accident, which draws the attention of the people nearby to the site of the accident.
5.3 CONCLUSION
In this project work, we have studied and implemented a complete working model using a Microcontroller. The programming and interfacing of microcontroller has been mastered during the implementation. This work includes the study of GSM and GPS modems using sensors.
The biggest advantage of using this project is, whenever the sensor is activated we will be getting the acknowledgement from GSM modem to our mobile numbers which are stored in EEPROM and GSM network operators have roaming facilities, and finding the location and sending information to user so that they can often continue to use there mobile phones when they travel to other countries etc..
REFERENCES
Website
‘ www.howstuffworks.com
‘ www.discovercircuits.com
‘ www.answers.com
‘ www.radiotronix.com
‘ www.wikepedia.com
Magazines
‘ Electronics for you
‘ Electrikindia
‘ Let us Go Wireless
Text Books
‘ Working with GSM Network By Cruis Leanardo
‘ Electrical Applications with GSM By Morris Hamington
‘ The 8051 microcontroller by Mazidi and Mazidi.
‘ 8051 micro-controller architecture, introduction to assembly programming by Parl vallal kannan