CAN BASED

COLLISION

AVOIDANCE SYSTEM

FOR AUTOMOBILES

BRIEF OVERVIEW :

Objective

Embedded system

What is CAS?

Existing system

Block Diagram

Power supply

ATmega16 Controller

Obstacle sensor

CAN, MCP2515 and MCP2551

LCD

DC Motor and L293D

Software Requirements

Operation

Advantages, Disadvantages

Future Scope

Conclusion

Objective of the Project :

• This project CAN BASED COLLISION AVOIDANCE

SYSTEM is intended for secure and smooth

journey.

• If the driver himself is not concentrating on

driving or any other parameters, which may cause

damage to vehicle as well a life, this intelligent

car/ vehicle warn the driver regarding the danger

ahead.

Embedded system : An Embedded System is one that has computer

hardware with software embedded in it as one of its important components.

Its software embeds in ROM (Read Only Memory). It does not need secondary memories as in a computer.

SOFTWARE PROGRAM

What is CAS ?

A collision avoidance system is that which is placed within a car to warn its driver of any dangers that may lie ahead on the road.  • how close the car is to other cars surrounding

it

• how much its speed needs to be reduced

while going around the curve

• how close the car is to going off the road

• uses visual and audio warnings to prompt the

driver

• initiates braking if the driver fails to respond

to the warnings

Existing system :

• Power train management system

• Antilock braking system (ABS)

• Acceleration skid control (ASC) system, etc,

• The functionality and wiring of these electric control

units (ECU) are getting more complicated.

• A high-level protocol CAN is adopted to interconnect

those CAN nodes with reliable communications

among sensors.

Block Diagram :

GP2D12 

ATMEGA

32

LCD

MCP 2515 MCP 2551

L293D

DC MOTOR

ATMEGA

32

LCD

MCP 2515 MCP 2551

NODE 1

NODE 2

Power Supply :

Transformer

Rectifier Filter Regulator

230V ACMains

Regulated 5V DC

ATMEGA 32 CONTROLLER :

• High-performance, Low-power AVR 8 - bit

Microcontroller

• Advanced RISC Architecture

• High Endurance Non-volatile Memory segments

• JTAG Interface

• Peripheral Features

• Special Microcontroller Features

• I/O and Packages - 40-pin

• Operating Voltages - 4.5-5.5V

• Speed Grades - 0-16 MHz

• Power Consumption - 1.1mA

Pin Diagram :

GP2D12 :

• It is an Analog distance sensor that uses

infrared to detect an object between 10 cm

and 80 cm away.

• Consists of PSD and infrared emitting diode

and signal processing circuit.

• High immunity to ambient light and colour of

object

• No external control circuitry required

GP2D12 :

CONTROL AREA NETWORK :

• CAN is a multi-master broadcast serial bus standard for

connecting electronic control units (ECUs)

• CAN is one of the best choices for embedded networking

applications.

• Each node is able to send and receive messages, but not

simultaneously.

• A message consists primarily of an ID (identifier), which

represents the priority of the message, and up to eight

data

bytes.

• The devices that are connected by a CAN network

are

typically sensors, actuators and other control

devices.

• These devices are not connected directly to the

bus, but

through a host processor and a CAN controller.

• Bit rates up to 1 Mbit/s are possible at network

lengths below

40 m.

• Each node requires a

Host processor

CAN controller

Transceiver

MCP2515 :

• It is a stand-alone Controller Area Network (CAN) controller that

implements

the CAN specification, version 2.0B

• MCP2515 has two acceptance masks and six acceptance filters that are

used to

filter out unwanted messages, thereby reducing the host MCUs

overhead.

• It is capable of transmitting and receiving both standard and extended

data and

remote frames.

• Operates from 2.7V – 5.5V

• It interfaces with microcontrollers (MCUs) via an industry standard

Serial

Peripheral Interface ( 10MHz)

• The device consists of three main blocks:

CAN Module ---- Control logic --- SPI Protocol block

MCP2551 :• The MCP2551 is a high-speed CAN, fault-tolerant device that

serves as the

interface between a CAN protocol controller and the physical

bus.

• It will operate at speeds of up to 1 Mb/s.

• It converts the digital signals generated by a CAN controller to

signals suitable

for transmission over the bus cabling.

• It also provides a buffer between the CAN controller and the

high-voltage

spikes that can be generated on the CAN bus by outside sources.

• Protection against damage due to short-circuit conditions

(positive or

negative battery voltage)

• Protection against high-voltage transients

• Automatic thermal shutdown protection

• Up to 112 nodes can be connected

• High noise immunity due to differential bus Implementation

Features :

Liquid crystal display :

Liquid crystal displays (LCDs)

have materials which combine

the properties of both liquids

and crystals.

They have a temperature range within which the molecules are almost as mobile as they would be in a liquid, but are grouped together in an ordered form similar to a crystal.

Since the LCD’s consume less power, they are compatible with low power electronic circuits and can be powered for long durations.

DC Motor :

• A DC motor is electromechanical device that

coverts electrical

energy into mechanical energy

• Motor gives power to the MCU

• Power to do physical works - to move robot

• It can be controlled easily with microcontrollers

• But the MCUs port are not powerful enough to drive

DC

motors directly , we need some kind of drivers.

• Very easy and safe is to use L293D chips

L293D :

L293D is a motor driver integrated circuit (IC).

Motor drivers act as current amplifiers since they

take a low-

current control signal and provide a higher-current

signal. This

higher current signal is used to drive the motors.

This chip is designed to control 2 DC motors  

L293D has output current of 600mA

The output supply has a wide range from 4.5V to

36V

Input logic 00 or 11

will

stop the

corresponding

motor.

Logic 01 and 10 will

rotate it in clockwise

and anticlockwise

directions.

Enable pins 1 and 9

must be high for

motors to start

operating.

Software Requirement

PROGRAMMING IN EMBEDDED CCODEVISION AVR C COMPILERKEIL SOFTWARE

Embedded C : Embedded C is a set of language extensions for the C Programming

language by the C Standards committee to address commonality

issues that exist between C extensions for different embedded

systems.

Historically, embedded C programming requires nonstandard

extensions to the C language in order to support exotic features such

as fixed-point arithmetic, multiple distinct memory banks, and basic

I/O operations.

In 2008, the C Standards Committee extended the C language to

includes a number of features not available in normal C, such as,

fixed-point arithmetic, named address spaces, and basic I/O hardware

addressing.

Embedded C use most of the syntax and semantics of standard C,

e.g., main() function, variable definition, data type declaration,

conditional statements (if, switch. case), loops (while, for), functions,

arrays and strings, structures and union, bit operations, macros, etc.

Codevision AVR :

• CodeVisionAVR is a complete set of tools designed for rapid

and efficient

software development for the Atmel AVR microcontrollers. Keil C cross compiler :

• Keil Software provides software development tools for the

family of

microcontrollers, they are

• IDE (Integrated Development environment)

• Project Manager

• Simulator

• Debugger

• C Cross Compiler , Cross Assembler, Locator/Linker

Compilers are programs used to convert a High Level

Language to

object code i.e source code into object code.

A cross compiler is similar to the compilers but we write

a program

for the target processor (like 8051 and its derivatives)

on the host

processors (like computer)

It means being in one environment you are writing a

code for another

environment is called cross development. 

OPERATION :

• Here   we    are    having     two    nodes    each  

node   Contain

ATMEGA 16 (AVR CONTROLLER), MCP2515 (CAN CONTROLLER),

MCP2551 (CAN TRANSRECEVER).

• In first node we are interfacing GP2D12 to find the

object, second

node contains DC motor.

• Initially motor is rotating with maximum speed. If any

object is

found in front of GP2D12 in node1 motor will stop in

node2 by

using CAN protocol.

• For this we have to develop two different application

programs

in embedded C.

Advantages

Collision Mitigation by BrakingCrash avoidanceRoad SafetyInjury and Accident PreventionCommercially marketable technical systemsLow costProduct Excellence due to Minimum

RequirementsHigh Alert system

DISADVANTAGES

The technical challenges for current collision avoidance systems lie in achieving high detection rates given an acceptable false alarm rate, under real-life driving situations.

The problem with curved roads is that sensors might mistake a car running in the opposite direction for a hazard on the lane where the CAS equipped vehicle is driving.

Cars Equipped with sensors running inthe opposite direction.

Applications :

• Used as a Warning System to avoid Collision in National Highways.

• Used by Police to Track the speed of the approaching vehicles.

• Used to detect an object in Extreme conditions like Fog and misty areas.

• Can be implemented in Robotic Applications.

• Can be used in large vehicles like Trucks and buses.

• Can be implemented in Aircraft and aerospace electronics.

• Can be used in Passenger and cargo trains.

• Can be implemented in Maritime electronics.

Real Time View :

• Future car collision-avoidance systems may be smart phone-based

• You could stick your cell phone on the dashboard, and it would use [its onboard sensors] to provide the feedback needed by the system

FUTURE SCOPE :

CONCLUSION

This briefly reviewed the automobile collision avoidance

problem in order to achieve safer transportation on highways.

Once achieved, this will not only save lives, but result in a

considerable amount of financial gains as well.

In order to develop the so-called smart highways and smart

cars, it is stated that the most importance difference from the

old practice is the fact that new design approach attempts to

completely avoid collision instead of minimizing the damage

by over-designing cars.

BIBLIOGRAPHY :Text Books :

[1] Steven F Barrett, ‘‘Embedded Systems Design With The Atmel AVR

Microcontroller’’, Morgan and Claypool Publishers,2008 .

[2] Jesse Russell, Ronald Cohn, ‘‘Controller Area Network’’, Bookvika

Publishing,2012 .

Web Portal :

[1] www.wikipedia.org

[2] www.atmel.com

[3] www.µvisionkeil.com

[4] www.authorstream.com

[5] www.electronics.howstuffworks.com

[6] www.allaboutcircuits.com