EMBEDDED SYSTEMS IN AUTOMOBILES

A Technical seminar report Submitted in the partial fulfillment of the requirements for

the award of the degreeof

BACHELOR OF TECHNOLOGY

INELECTRONICS AND COMMUNICATION ENGINEERING

Submitted by

G.J.S PAVANKUMAR-09MD1A0417

Under the Esteemed Guidance ofMrs.J.Padma M.Tech,

Assoc.Professor

DEPARTMENT OFELECTRONICS & COMMUNICATION ENGINEERING

RAJAMAHENDRI INSTITUTE OF ENGINEERING &

TECHNOLOGY(Affiliated to JNTU University, Kakinada)

Bhoopalapatnam-533105, EAST GODAVARI Dist. (A.P)

RAJAMAHENDRI INSTITUTE OF ENGINEERING & TECHNOLOGY

DEPARTMENT OF

ELECTRONICS & COMMUNICATION ENGINEERING

CERTIFICATE

This is to certify that the project report entitled“EMBEDDED SYSTEMS IN AUTOMOBILES”, Submitted by Mr.G.J.S

PAVANKUMAR in the partial fulfillment for the award of degree of Bachelor in Engineering for Electronics and communication Engineering, from Rajamahendri

institute of Engineering and technology, Bhoopalapatnam, affiliated to the Jawaharlal Nehru Technological University (JNTU), Kakinada, is a record of bonfide work carried out by her under my guidance and supervision. The results embodied in this project have not been submitted to any other University or Institute for the award

of degree or diploma.

CO-ORDINATOR HEAD OF THE DEPARTMENT Mrs.J.Padma, M.Tech Mr. Srinivas, M.Tech Associate Professor Associate Professor

ACKNOWLEDGEMENT

I would like to thank my technical seminar co-ordinator Mrs.J.Padma, Associate Professor, Department of ECE, for her guidance and help throughout the development of the seminar work and for chiseling the real magnitude and dimension of the seminar. I feel grateful for the dexterous attitude and zeal she has installed in us.

I would like to thank Mr.R.Srinivas, Associate professor and Head of the Department of ECE, for his assistance and constant back up because of which this technical seminar could be completed successfully.

I would like to express our gratitude to Dr.P.G.Ramanujam,Principal, Dr.K.Ramesh babu, Secretary, and the Management of RAJAMAHENDRI INSTITUTE OF ENGINEERING AND TECHNOLOGY for their support and providing a hassle-free environment without which this technical seminar would not have seen the light of the day.

Last but not the least; I would like to express our gratitude to all the teaching and non-teaching staff members of Department of ECE who have been directly or indirectly a part of this journey. An endeavor over a long period can only be successful by constant effort and encouragement. I wish to take this opportunity to express our deep sense of gratitude to all the people of RAJAMAHENDRI INSTITUTE OF ENGINEERING AND TECHNOLOGY. Who have extended their cooperation in various ways during this technical seminar. It is my pleasure to acknowledge the help of all the respected elders.

G.J.S PAVAN KUMAR (09MD1A0417).

CONTENTS

List of Figures i Abstract ii

Chapter 1.INTRODUCTION …………………………………………. 1.1Objective 1.2What are embedded systems? 1.3Applications of Embedded systems.

Chapter 2. FINE ART AUTOMATION………………………………..

2.1 Introduction 2.2 Driving unitChapter 3. EMBEDDED SYSTEMS IN CARS .......................... 3.1Automated cruise control 3.2Anti-lock break system

3.3Automative security 3.4Traction control

Chapter 4.ADVANTAGES

Chapter 5.CONCLUSION ………………………………………...

LIST OF FIGURES

1. Figure 1: Blockdiagram …………………………………….….

2. Figure 2: Block diagram of control system………………..…...

3. Figure 3: Prototype of automation……………………….……..

4. Figure 4: Driving unit…………………………………………...

5. Figure 5: High pitch sound……………………………………...

6. Figure 6: Low pitch sound………………………………………

7. Figure 7: Transmitting and receiving radio waves………………

8. Figure 8: Virtual vehicular system………………………………

9. Figure 9: Traction control………………………………………..

ABSTRACT

The technical Brilliance and Developments in

different fields has led to a drastic change especially in the

communication field. Devices with intelligence rule the world.

Imbibing intelligence to these devices is through a system called

“EMBEDDED SYSTEMS”. It is the evolution or further development of

the computing system. Its applications provide marvelous

opportunities for ingenious use of computer technology. Almost

every new system introduced is an example of Embedded System.

These systems are more intelligent and autonomous.

Embedded Systems are combinations of hardware

and software that are mounted on compact electronic circuit boards

integrated into devices. They are engineered or intended to perform

one specific function in a specific environment. An important

decision in the design of an embedded system is the selection of the

processor(s) around which the rest of the system is to be built. It is

a chip that contains a microprocessor, some memory & I/O interface

circuitry useful in embedded applications and is often called an

‘EMBEDDED PROCESSOR’ or ‘MICRO CONTROLLER’ chips as they

perform important control functions, and are based on micro

controller.

The current topic “Automation of car” that we are

going to present is one of the fine examples of Embedded System.

There are many paradigm shifts taking place due to information

explosion and the concept of autonomous vehicle is one shift. The car, which is

embedded, can simulate the human driver completely and direct the vehicle on the

road. Autonomous vehicle is the drastic change in technical brilliance and

developments in different fields with EMBEDDED SYSTEM as pioneer.

CHAPTER-1

INTRODUCTION

1.1 Objective

The term embedded system is quite a complex one. Simply it is a

combination of hardware and software that forms the component of a larger

system, this in turn is programmed to perform a range of dedicated functions

usually with a minimal operator intervention. In embedded systems the hardware

is normally unique to a given application, computer chips are embedded into the

control electronics to manage the products functionality.

Embedded systems are rapidly becoming a catalyst for change in

computing data communications, telecommunications, industrial control and

entertainment sectors. New innovative applications in these as well as other areas

such as home networking and car infotainment will roll out in the near feature

1.2 What are embedded systems?

We read in newspapers that a doctor had successfully transplanted a

cardiac pacemaker in his patient’s chest by sitting around 200kilometres away.

Also we know about driverless cars that could take us to the destiny by using its

inbuilt navigation systems. Embedded microprocessors or micro controllers are

the brain behind these.

An embedded system is any device controlled by instructions stored on a

chip. These devices are usually controlled by a micro processor that executes the

instructions stored on a read only memory(ROM) chip.

The software for the embedded system is called firmware. The firmware

will be written in assembly language for time or resource critical operations or

using higher level languages like C or embedded C. The software will be

simulated using micro code simulators for the target processor. Since they are

supposed to perform only specific tasks, these programs are stored in read only

memories(ROMs).Moreover they may need no or minimal inputs from the user,

hence the user interface like monitor, mouse and large keyboard etc,may be

absent.

Embedded systems are computer systems that monitor, respond to, or

control an external environment. This environment is connected to the computer

system through sensors, actuators, and other input-output interfaces. It may

consist of physical or biological objects of any form and structure. Often humans

are part of the connected external world, but a wide range of other natural and

artificial objects, as well as animals are also possible.

Embedded systems are also known as real time systems since they

respond to an input or event and produce the result within a guaranteed time

period. This time period can be few microseconds to days or months. The

computer system must meet various timing and other constraints that are

imposed on it by the real-time behavior of the external world to which it is

interfaced. Hence comes the name real time. Another Name for many of these

systems is reactive systems, because their primary purpose is to respond to or

react to signals from their environment. A real time computer system may be a

component of a larger system in which it is embedded; reasonably such a

computer component is called an embedded system.

Embedded systems control engine management systems in automobiles,

monitor home heating systems and regulate the quiet operation and the even

distribution of laundry in washing machines. They are the heart of toys like

Furby and Tamagotchi, of golf balls that cannot get lost and of gas pumps at

gasoline stations that advertise nearby restaurants on video. Above all, state-of-

the art communications equipment like WAP mobile telephones, MP3 players,

set-top boxes and Net devices would not be possible without these powerful

miniature brains.

1.3 Applications of embedded systems

Applications and examples of real time systems are ubiquitous and proliferating,

appearing as part of our commercial, government, military, medical, educational,

and cultural infrastructures. Included are:

Vehicle systems for automobiles, subways, aircraft, railways and ships.

Traffic control for highways, airspace, railway tracks and shipping lanes.

Process control for power plants, chemical plants and consumer products such as soft drinks and beer.

Medical systems for radiation therapy, patient monitoring and defibrillation

Military uses such as firing weapons, tracking and command and control.

Manufacturing systems with robots.

Telephone, radio and satellite communications.

Computer games.

Multimedia systems that provide text, graphic, audio and video interfaces.

Households systems for monitoring and controlling appliances.

Building managers that controls such entities as heat, light, Doors and elevators.

CHAPTER-2 FINE ART OF AUTOMATION

2.1 Introduction

We load the code of our destination in the dashboard

computer and turn the car on, while we remain seated carefree on the

rear seats. Then its all the job of the ‘unknown’ to drive it on the roads,

bridges, thought the bazaars, past the crossings to the destination,

without getting challenged even once for traffic rule violations.

A fully computerized car capable of doing almost every thing a

car lover would want to. Almost all automobiles will interact with

computer on dashboards. From ordering pizza to booking tickets at the

nearest theatre, things would be as easy as giving orders to your servant.

As a matter of fact, vehicles all over the world are now fitted with

intelligent devices that make the vehicles to respond to various factors –

be it climate control, sudden accelerations or braking or even self-repair

of modules.

The finger print technologies have been introduced to enter and start your

car with the touch of a finger. The fingerprint, which is acting as a key,

would trigger a check of the mirrors, steering wheel, radio and

temperature to ensure that they're the way you like them. The

convenience of fingerprint recognition technology comes with heightened

security. Unlike personal identification numbers, passwords and keys,

each person's unique fingerprints can't be duplicated, lost or forgotten.

.

Description:

As stated above that a vehicle can run by itself with out the

intervention of human beings by the embedded intelligence in it. For this

purpose Global Positioning System (G.P.S) using satellites can provide

positioning information and proves to be a versatile all-time. For still

higher accuracy wide area differential GPS is used, which offers a robust

system that readily deals with selective availability errors and satellite

clock errors.

The models for GPS also include aiding sensors, e.g. dead reckoning, radar

and camera. A computer is simply required to feed destination into a

dashboard computer. Highly sensitive actuators simulate a human driver

completely and direct the vehicle on the road. The vehicle transmitter

broadcasts its position and velocity to other immediate participants for

collision-avoidance and lane changing manoeuvres. Forward and reverse

motions and u-turns are precisely achieved as per route guidance

requirements. Furthermore, an accurate steering control is obtained using

Pulse Code Modulation technique and acceleration/braking control is

successfully implemented using learning adaptive system The reliability,

efficiency and cost effectiveness of an autonomous vehicle depend mainly

on how judiciously its navigation sensors, perception unit and computer

control is incorporated.

The driver’s activity is influenced by several factors that depend on driver itself and is

environment such as traffic density, traffic status, time of travel and weather. Thus the

driving

The vehicle is required to blend its environmental perception

capabilities with its intelligent controls in order to affect optimal path-

planning strategies that not only avoid obstacles but also minimize criteria

such as time of travel, fuel consumption, exposure to pollution/danger,

etc. however basic driving functions consists of lane-keeping, safe

distance maintenance, timely lane changing and overtaking. The key to all

these driving tasks is collision avoidance.

The Master Control Station (MCS) receives the positioning

information from the satellite by employing WADGPS concept. The MCS is

linked to GPS instrumented position location systems (PLS) installed on

the autonomous vehicles through a data link sub system (DLS). The DLS

can either use VHF or UHF or L-band, incorporating time division multiple

access protocol to handle on the roads. A block forward error correction

code is employed to protect and maintain the message integrity.

The desired destination and starting position of the vehicle together with the time of travel,

manifest an optimal route on the road network. Once the vehicle commences the journey the

sensors continuously keep track of the direction and displacement of the vehicle initial

calibration is a little crucial for dead reckoning performance; how ever a feed back calibration

indicated in fig suggested to obtain distance accuracy better than 99.9 percent.

The new generation microprocessors promises further increase in system

capabilities while simultaneously shrinking both volume and power consumption of the

autonomous vehicle embedded system. The digital road maps, available on CD-ROM’s have

substantially increased safety of automobiles. These maps along with GPS navigation provide

a

Feasible solution to autonomous vehicle system. The expert system technologies are

integrated with digital maps along with the CCD camera images, magnetic compass, and the

GPS system, for obtaining a real time intelligent decision support navigation package. The

integration of GPS and communication suggests an efficient transportation system for

increasing the road traffic safety smooth driving without traffic jams and a comfortable

driving environment. Furthermore the autonomous vehicle relies on such intelligent system

integration that leads to complete collision free in time of real time situation.

The internal platform and rate gyro and accelerometer package keeps the vehicles central

processing unit (CPU) well informed about the incremental changes in the vehicles

parameters. The wheel odometers provide the vehicle traveling distances by multiplying the

number of electronically generated pulses by a constant, depending upon wheels perimeter

The information concerning deviation from the road center is obtained by magnetic as well

as optical sensors, and fed to the CPU. The GPS receiver updates the vehicles position and

velocity to centimeter/decimeter levels as required for the lateral or longitudinal control

actions. The autonomous vehicle embedded software mission finally yields the estimates for

throttle and heading angle increments for a safe and accident free manoeuvre. The following

figure gives an indication of all the technologies used in a car

.

2.2 In the driving seat:

There are several tasks in which real time OSs beat their desktop

counterparts hands-down. A common application of embedded systems in the

real world is in automobiles because these systems are cheap, efficient and

problem free. Almost every car that rolls off the production line these days

makes use of embedded technology in one form or the other.RTOSs are

performed in this area due to their fast response times and minimal system

requirements.

Most of the embedded systems in automobiles are rugged in nature, as

most of these systems are made up of a single chip. Other factors aiding their use

are the low costs involved, ease of development, and the fact that embedded

devices can be networked to act as sub modules in a large system. No driver

clashes or ‘system busy’ condition happen in these systems. Their compact

profiles enable them to fit easily under the cramped hood of a car.

Embedded systems can be used to implement features ranging from

adjustment of the suspension to suit road conditions and the octane content in the

fuel to anti lock braking systems (ABS) and security systems. Speaking of the

things nearer home the ‘computer chip’ that control fuel injections in a Hyundai

Santro or the one that controls the activation of air bag in a Fiat in a weekend in

nothing but an embedded system. Right from brakes to automatic traction control

to air bags and fuel/air mixture controls, there may be upto 30-50 embedded

systems within a present-day car. And this is just a beginning.

CHAPTER-3 EMBEDDED SYSTEMS IN AUTOMATION

.

AUTOMATED CRUISE CONTROL:

3.1Cruise control

Embedded systems can also make driverless vehicle control a reality. Major

automobile manufacturers are already engaged in work on these concepts. One

such technology is Adaptive Cruise Control (ACC).

ACC allows cars to keep safe distances from other vehicles on busy

highways. The driver can set the speed of his car and the distance between his

car and others. When traffic slows down, ACC alters vehicle speed using

moderate braking. This ensures that a constant distance is maintained between

cars. As soon as traffic becomes less, ACC moves up to the desired cruise speed

that has been set by the driver. The driver can over ride the system any time he

wants to be breaking.

Each car with ACC has a micro wave radar unit or laser transceiver fixed

in front of it to determine the distance and relative speed of any vehicle in the

path. The ACC computer (What else but an embedded system or a grouped

system of embedded system) constantly controls the throttle and brakes of the

car. This helps to make sure that the set cruise speed or adapted speed of traffic

at that time is not exceeded.

Working principle of Automated cruise control:

As already mentioned each car with ACC have a micro wave radar unit fixed in

front of it to determine the distance and relative speed of any vehicle in it’s

path. The principle behind the working of this type of radar is- the Doppler

Effect.

Doppler Effect:

Doppler Effect is the change in frequency of the waves when there is a

relative motion between the transmitting and receiving units. The two figures

below clearly show the Doppler Effect.

1. Higher Pitch Sound

In this case the vehicle is speeding towards the stationary listener. The

distance between the listener and the car is decreasing. Then the listener will hear

a higher pitch sound from the car, which means the frequency of sound, is

increased.

2. Lower pitch sound

In this case the vehicle is moving away from the listener. The distance

between and the car is increasing. Then the listener will hear a lower pitch sound

from the car, which means the frequency of sound, is decreased. So that is the

Doppler Effect in case of sound waves.

Similarly the radar unit in ACC will be continuously transmitting radio

waves. They will be reflected and echo singles (reflected waves) will be having

the same frequency or different frequency depending on speed/position of the

object due to which the echo singles originate. If the echoes singles have the

same frequency it is clear that there is no relative motion between the

transmitting and receiving ends. If the frequency is increased it is clear that the

distance between the two is decreasing and if the frequency is decreased it means

that the distance is increasing.

The figure below shows a car having ACC transmitting and receiving

radio waves.

In the above case, the gun transmits the waves at a given frequency

toward an oncoming car. Reflecting waves return to the gun at a different

frequency, depending on how fast the car being tracked is moving. A device in

the gun compares the transmission frequency to the received frequency to

determine the speed of the car. Here, the high frequency or the reflected waves

indicate the motorist in the left car is speeding.

The embedded system is connected to the radar unit and its output will be

sent to breaking and accelerating unit as early mentioned the embedded system is

a device controlled by instructions stored in a chip. So we can design the chip or

ACC having an algorithm such that it will give output only when the input

signals are less than the corresponding safe distance value. So only when the

between the car and the object in front of it is less then the same distance value

the embedded system will give output to the breaking and the accelerating units.

Thus the safe distance will be kept always. That’s how the ACC works.

ABOUT THE BEAUTY OF ACC:

As the driver in the next lane swerves in front of you, you feel that gas

back off and the brakes grab in the car you’ re driving- a Mercedes Benz S-

class luxury vehicle, the first passenger car equipped with a technology called

adaptive cruise control. The technology makes these adjustments even though

you haven’t touched the brake or gas pedal.

At a safe distance behind, your Mercedes settles to a speed matching that

of the driver in front of you. That’s too slow, so after a look in your rear view

mirror you pull into the empty outside lane and feel the acceleration as your car

speeds up to the preset cruising speed. You still haven’t press the accelerator

pedal. That’s the beauty of this racing star of the auto industry, a millimeter-

wave radar technology that promises not only to make driving easier, but to

ignite a market for gallium arsenide and other compound semi conductor

components.

Although grey hound buses and some heavy- goods vehicles have been

fitted with automotive radar systems, the Mercedes is reckoned to be the first

passenger automobile to sport this advanced use of electronics, and observers say

it is likely to lead a proliferation of the technology. The Mercedes Benz system

uses a 77-GHz Doppler radar linked into the electronic control and braking

system to maintain a safe distance between a car with the system and the vehicle

in front of it. Daimler Benz Aero space has completed the design of a hybrid 77-

GHz radar, called Tempo mat, which is being considered for deployment.

Holger Meinel, senior researcher at Daimler Benz Aerospace AG (Ulm,

Germany), was quick to make a point stressed by all the companies working in

this field. “This is not anti- collision radar” he said. “It’s not a safety feature, it’s

a comfort feature”.

The source of this distinction is concerned that if adaptive cruise control

is marketed as a safety feature, the first accident that occurs involving a vehicle

equipped with millimeter- wave radar will bring a damaging liability suit. That’s

why companies are at great pains to point out that the driver retains control and

responsibility.

3.2Antilock Break system

Vehicle safety continues to be a critical issue at all levels of the automotive

supply chain. And, as consumers spend more and more time on the road they are

constantly looking fo

safety improvements. There are two types of safety system existing. Active safety

aims at preventing accidents happening in the first place. Cars are equipped with a

number of systems to help the driver control the car before an accident might occur.

Passive safety describes the safety systems which are built into cars to protect the

driver, the occupants and other vulnerable road users after the accident has happened.

Developments in active safety offer real life saving advantages to drivers,

particular in the wet, winter months. With the facts before them, it is believed that

drivers would unhesitatingly demand these systems in their cars as they offer

substantial benefits in reducing accidents on our roads.

Anti-lock brake system (ABS) is one of the most important equipments in the

active safety system. It is a system on motor vehicles which prevents the wheels

from locking while braking. The purpose of this is twofold: to allow the driver to

maintain steering control and to shorten braking distances by allowing the driver to

fully hit the brake without the fear for skidding or the loss of control.

On high-traction surfaces such as bitumen, whether wet or dry, most ABS-

equipped cars are able to attain braking distances better (i.e. shorter) than those that

would be easily possible without the benefit of ABS. For a majority of drivers, in

most conditions, in typical states of alertness, ABS will reduce their chances of

crashing, and/or the severity of impact. In such situations, ABS will significantly

reduce the chances of a skid and subsequent loss of control. In gravel and snow,

ABS tends to increase braking distances. On these surfaces, locked wheels dig in

and stop the vehicle more quickly. ABS prevents this from occurring. Some ABS

calibrations reduce this problem by slowing the cycling time, thus letting the wheels

repeatedly briefly lock and unlock. The primary benefit of ABS on such surfaces is

to increase the ability of the driver to maintain control of the car rather than go into a

skid— though loss of control remains more likely on soft surfaces like gravel or

slippery surfaces like snow or ice.

A typical ABS is composed of a central electronic unit, four speed sensors for

four wheels respectively, and two or more hydraulic valves on the brake circuits. It

is a complicate system integrating mechanics, electronics and control devices, and

the development procedure has also change greatly against the old methods. This

process can be divided into 5 basic stages:

1. The first stage consists of system definition where design engineers specify

and define the requirements for the embedded control system. This is often

done with text based files created on a desktop PC. In some instances real-

world empirical data is acquired as part of the specifications.

2. In the second stage, rapid prototyping, the design engineer develops the

control strategy in a simulated environment on the desktop PC or workstation

and then creates an initial prototype of the system with real-time hardware.

3. In the third stage, the code generation phase, production code is generated

and manually tweaked for the target hardware. At this point the production

code is running on the target hardware and not on the prototype hardware

anymore

4. During the fourth stage, the design engineer will test out the target

hardware against a simulated environment. Real-Time hardware is used to

simulate the real-world environment that the control system interfaces with.

5. Finally, the target hardware is deployed and integrated into the system and

final testing is done to ensure that design specifications were met.

Within all five stages, computer simulation plays a vital role. Computer

simulation for vehicle components design is progressing greatly in recent years.

During computer simulation, computer models are used to recreate or simulate the

vehicle environment, and the ECU is then interfaced to the simulated environment.

It is only in recent years that the virtual simulation of full vehicle systems has

become a serious effort for the automotive industry. Most of the large companies

have developed their own facilities to simulate vehicles in virtual realistic

environments, each of which is in a different setting with different research

objectives.

A general virtual vehicle system is developed and made specified modification

for ABS controller design, furthermore the ABS control prototype is built based on

this system. This system consists of two connected parts: pure software simulation

and hardware in loop (HIL) simulation. In the first part all the components are

modeled in software, developed in the platform of MATLAB/SIMULINK. ABS

control logic is developed and tested in conjunction with the vehicle models to study

the behavior of the overall system and to optimize the algorithm used in it before

building prototypes.

In the second part HIL platform is constructed including the computer cluster, the

hardware-vehicle interaction (sampling, time lags, etc.), actual vehicle components,

ABS controller and actuator. All the components are connected together by controller

area network (CAN) (SAE, 2056/1, and 2056/2, 1994), including engine, ABS

controller, sensors and vehicle model. Rather than testing these components in

complete actual system setups, virtual system allows the testing of new components

and prototypes by communicating with software models on the main computer by

CAN interface. Furthermore this technology is flexible enough to allow expansion and

reconfiguration, in accordance with the development of modern automotives. For the

requirement of real time system, one computer is used to run the vehicle model

exclusively and use another one for data and graphic processing; they are connected

through Ethernet based on TCP/IP. In the procedure of HIL simulation, a novel

simulation algorithm is proposed to deal with the abrupt changes of hydraulic

pressure and make the entire system robust and stable. The structure of entire

hardware and software system is shown in figure.

Figure : Entire structure of virtual vehicle system.

An integrated user-friendly interface including vehicle parameters database

editors, configurations and visualization tools are also used to interact with the core

components. MATLAB, database and EXCEL are integrated into this system

through Visual C++ programming platform on assistant computer. Microsoft

ACCESS is chosen as the data storage database and ADO is used for data

operation. The experiment data is stored into database through Ethernet. The

necessary data can be taken out from database and processed in MATLAB after

being converted to the proper data format. Furthermore the desirable data and

figures can be imported into EXCEL, which convenience the data analysis and

exportation for ABS designers.

Conventional ABS control algorithms must account for non-linearity in brake

torque due to temperature variation and dynamics of brake fluid viscosity.

Although fuzzy logic is rigorously structured in mathematics, one advantage is the

ability to describe systems linguistically through rule statements. The superior

characteristics through the use of fuzzy logic based control are realized rather than

traditional control algorithms to ABS controller. Due to the nature of fuzzy logic,

influential dynamic factors are accounted for in a rule based description of ABS.

This type of intelligent algorithm allows for improvement and optimization of

control result. This algorithm is tested on the HIL platform and the desirable results

are achieved.

3.3Embedded system design for automated security:

With increasingly sophisticated security devices reaching the

automotive market, onewould think auto security has come to be in business. The

events of disasters for vehicles and drivers happen frequently so that more and

more devices for a vehicle security effectively appear. On one hand, the car

security trade is alive and well. On the other hand, for the automotive electronics

designers, the automotive industry’s primary goals of safety, cost, and reliability

have to be concentrated on. Therefore, embedded technology are more and

more used to design automotive systems so that many embedded products for

security come into the market. The devices include digital devices, password

devices, communication devices, video system and so on. Among the

digital devices for automotive safe, digital key with the embedded small

wireless radio sender, the corresponding receiver is installed inside the car.

When the key is inserted, the wireless signal with twenty digital codes is sent, if

they are ensured, the car will run. There is also a password lock. This lock is

based on the principle of radar radio. There is a chip inside the key hole. When

the key turns, the chip will check the password sequence. The communication

system for a car safe is also popular. For example, a telephone control system

controls cars by calling such as closing door and windows, controlling fuel

supply and closing other electronic devices. A GPS vehicle satellite navigation

system tracks cars by consulting the geography system and avoiding electric

wave interference. Moreover, recently video systems for car safe have come to

be developed. A micro-spy camera is one of them. Its size is so small that it can

be located at any place of cars. The camera can also work under the weak light

and be connected to the phone networks. The shot images will be transferred to

the control center to be recognized.

Those devices and systems are helpful to vehicle safety, but they also have

some defects. The digital device only focuses on the key. If the key is lost, the

device has no use. Although the communication system can track the objects, this

kind of monitor costs too much and is very expensive. The camera is useful to

monitor but only depending on the camera is too simple because the persons’

behaviors have to be judged.

Among security systems in the field of automotive and others, tracking, recognizing

and detecting objects using a video sequence are topics of significant interest. Cai and

Agganval (Aggarwal and Cai, 1999) reported a variety of methods for analyzing

human motion. In (Harwood and Davis, 1998; Haritaoglu and Davis, 1999),

Haritaoglu, Harwood and Davis tracked both single and multiple humans in outdoor

image sequences using a PC. In (Oliver et al., 1999), Nuria, Rosario and Pentland

recognized two-person interactions from perspective-view image sequences. They

tracked persons and recognized their interaction using trajectory patterns. Meanwhile,

some researchers developed applications include one or more embedded systems.

Especially recently, more and more appropriately without detailed instructions from

humans. In (Mahonen, 1999), Mahonen proposed a wireless intelligent surveillance

camera system that consists of a digital camera, a general-purpose processor or DSP

for image processing and a wireless radio modem. In (Shirai et al., 1999), Shirai

introduced a real-time surveillance system with parallel DSP processors (TI

TMS32OC40). Their system consists of several boards connected in series. It can

compute optical flow computation in floating point faster than 30 frames per second.

In this system, a DSP is located between the two memories. The DSP computes and

transfers the image data from the video memory to the other memory, which is

connected to the next processing stage.

A security system is built based on Independent Component Analysis (ICA) for

automotive security. The goal of ICA is to recover independent sources given only

sensor observations that are unknown linear mixtures of the unobserved independent

source signals. In contrast to correlation-based transformations such as Principal

Component Analysis (PCA), ICA not only de-correlates the signals (2nd-order

statistics) but also reduces higher-order statistical dependencies, attempting to make

the signals as independent as possible. This character is well used in the field of

image recognition.

Unlike other methods, the proposed method is to detect the abnormal motion

from activities of a person himself based on ICA. In the first step almost images are

defined. These images are about abnormal motions of people around the door of

automotive according to the opinions of observers. These motions are stored in

image database, which is used for motion recognition through matching the real time

image caught by a micro camera. Before ICA processing, the image sizes are

normalized, both the shot images and the images in the database. In order to adapt

to different type of camera and color content, each pixel (RGB-triple) is projected

onto a plane by average RGB values. The feature vectors of images are extracted

using ICA and organized into categories in order to improve the precision and

decrease time consumption using cluster algorithm. In the procedure of abnormal

pattern recognition, the basic cluster is specified in advance and make the program

identify the remained images into basic cluster automatically. A novel similarity

calculation method is developed to recognize the most similar image from the

certain cluster according to the extracted feature vectors. The array of feature

vectors and the pattern matrix of images in the database extracted using ICA are

stored in RAM on the FPGA board and therefore the image database is seamlessly

integrated to the real time system.

In the second step, the micro digital camera is embedded into a terminal board

and fixed in the rearview mirror of car. It is used to catch the movements of people

who present around the door kept under surveillance and do some preprocessing.

The image data is transferred from the sending module of Ni3, which is a wireless

communication device to the receiving module, connected

In the second step, the micro digital camera is embedded into a terminal board

and fixed in the rearview mirror of car. It is used to catch the movements of people

who present around the door kept under surveillance and do some preprocessing.

The image data is transferred from the sending module of Ni3, which is a wireless

communication device to the receiving module, connected to the FPGA board for

receiving data.

In designing the security system, it is considered to take full advantage the

unique characteristics feature vectors of shot images are extracted using pattern

matrix. From comparing the feature vectors of shot image and the cluster

centroid, it is possible to get which cluster the shot images belong to respectively.

After that the most similar image can be achieved from the corresponding cluster.

The security level of a person can be calculated and any appearance of a person

deemed threatening can be set to trigger an alarm. Furthermore this system can be

connected to engine management system to control the start of engine. Therefore if

a person is regarded as insecurity, he can not run the can even if he enters into the

cabof the embedded system. For example, image processing such as feature

extraction and cluster is more effectively performed on an embedded processor.

The computational complexity of each operation and the transfer rate and overall

suitability of each processor were evaluated. In the discussion below, the

algorithms, calculating stages and simulation results are described. Figure 2.2

presents an overview of the

system.

A security system is built based on Independent Component Analysis (ICA) for

automotive security. The goal of ICA is to recover independent sources given only

sensor observations that are unknown linear mixtures of the unobserved independent

source signals. In contrast to correlation-based transformations such as Principal

Component Analysis (PCA), ICA not only de-correlates the signals (2nd-order

statistics) but also reduces higher-order statistical dependencies, attempting to make

the signals as independent as possible. This character is well used in the field of

image recognition.

Unlike other methods, the proposed method is to detect the abnormal motion

from activities of a person himself based on ICA. In the first step almost images are

defined. These images are about abnormal motions of people around the door of

automotive according to the opinions of observers. These motions are stored in

image database, which is used for motion recognition through matching the real time

image caught by a micro camera. Before ICA processing, the image sizes are

normalized, both the shot images and the images in the database. In order to adapt

to different type of camera and color content, each pixel (RGB-triple) is projected

onto a plane by average RGB values. The feature vectors of images are extracted

using ICA and organized into categories in order to improve the precision and

decrease time consumption using cluster algorithm. In the procedure of abnormal

pattern recognition, the basic cluster is specified in advance and make the program

identify the remained images into basic cluster automatically. A novel similarity

calculation method is developed to recognize the most similar image from the

certain cluster according to the extracted feature vectors. The array of feature

vectors and the pattern matrix of images in the database extracted using ICA are

stored in RAM on the FPGA board and therefore the image database is seamlessly

integrated to the real time system.

In the second step, the micro digital camera is embedded into a terminal board and

fixed in the rearview mirror of car. It is used to catch the movements of people who

present around the door kept under surveillance and do some preprocessing. The

image data is transferred from the sending module of Ni3, which is a wireless

communication device to the receiving module, connected to the FPGA board for

receiving data.

The feature vectors of shot images are extracted using pattern matrix. From

comparing the feature vectors of shot image and the cluster centroid, it is possible

to get which cluster the shot images belong to respectively. After that the most

similar image can be achieved from the corresponding cluster. The security level of

a person can be calculated and any appearance of a person deemed threatening can

be set to trigger an alarm. Furthermore this system can be connected to engine

management system to control the start of engine. Therefore if a person is regarded

as insecurity, he can not run the can even if he enters into the cab.

In designing the security system, it is considered to take full advantage the

unique characteristics of the embedded system. For example, image processing such

as feature extraction and cluster is more effectively performed on an embedded

processor. The computational complexity of each operation and the transfer rate

and overall suitability of each processor were evaluated. In the discussion below,

the algorithms, calculating stages and simulation results are described. Figure

2.2 presents an overview of the system.

3.4TRACTION CONTROL:

Automatic traction control (ATC) systems (also called ASR for

automatic slip regulation) are currently available as regular production options

on most heavy commercial vehicles (power units). These systems are integrated

with ABS which is now mandatory for all air-braked vehicles and vehicles with

hydraulic brakes having a GVWR in excess of 10,000 lbs. These systems utilize

components of the ABS as well as additional components specific to the ATC.

The ABS wheel speed sensors are used to determine drive axle(s)

slip by comparing the speed of the drive axle(s) wheels to the speed of the

wheels on the steering axle. When the speed of the drive axle(s) exceeds that of

the steering wheels by some predetermined amount, the traction control

software in the ABS electronic control unit (ECU) can command either of two

different events: 1) a reduction of engine speed (RPM) and 2) application of the

drive axle brakes on one side of the drive axle(s).

Engine speed reduction is accomplished by the ABS ECU

sending a signal to the engine ECU over the electronic data link between the

two ECUs. This data link is provided if the traction control option is ordered or

in some cases if the vehicle has an engine retarder. The communication

protocol can either follow SAE J1922 or J1939. While all current ABS ECUs

can support either protocol, J1939 is becoming more common and is considered

to be the system of the future since it allows faster communication

Due to the fact that ATC is highly integrated with the

engine, ABS and pneumatic systems, retrofitting ATC to older vehicles is

generally not practical.

Automatic application of the drive axle brakes occurs only if the

speed difference between the left and right wheels exceeds a predetermined

level. In that case the brakes on the faster wheel are applied until speed is

reduced to match the other wheel. Brake application is made via a special

traction control valve that is installed in the rear-axle relay valve control port.

During normal service braking, this valve passes air from the foot control valve

directly to the relay valve, but in the case of a traction control event this valve,

which is also connected to the drive-axle brake system air reservoir, applies full

reservoir pressure to the rear-axle relay valve control port. The delivery air from

the relay valve is then directed to the appropriate brake by controlling the ABS

valves. The ABS valve on the rear brake that needs pressure is left open and the

valve on the opposite side is closed. The ASBS valve also modulates (controls)

the pressure level at the brake to control wheel slip. The ABS ECU performs

this control function via its traction

control algorithm in the ABS ECU.

Brake application during traction control only occurs at

speeds below 25 to 30 mph. Above that speed the brake control function in

the ATC algorithm is turned off since there is the possibility of loss of

control of the vehicle due to only one brake suddenly

automatically applying when the vehicle is on a very slippery surface. Brake

overheating during a prolonged traction control event is also a possibility at the

higher speeds.

CHAPTER-4

ADVANTAGES OF EMBEDDED SYSTEMS IN CARS

Accidents can be reduced as the applications.

Safety can be increased.

Human losses and property can be saved.

CHAPTER-5

CONCLUSION

Making the autonomous easy to operate for the user and the designers

should concentrate more in producing autonomous cars.

Due to speed control technique, accident free driving is possible and fuel

savage is also made possible by the technique.

So that we could find ourselves using these autonomous cars in the near

future.

REFERENCES

www.wikepedia.com

www.kpsec.freeuk.com

www.digichip.com

www.datasheets4u.comwww.datasheets4u.com