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Seminar Report ’03 Embedded System in Automobiles
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.
Dept. of IT MESCE Kuttippuram1
Seminar Report ’03 Embedded System in Automobiles
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.
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.
Dept. of IT MESCE Kuttippuram2
Seminar Report ’03 Embedded System in Automobiles
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.
Multi media systems that provide text, graphic, audio and video
interfaces.
House holds systems for monitoring and controlling appliances.
Building managers that controls such entities as heat, light, Doors and
elevators.
Dept. of IT MESCE Kuttippuram3
Seminar Report ’03 Embedded System in Automobiles
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.
Dept. of IT MESCE Kuttippuram4
Seminar Report ’03 Embedded System in Automobiles
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.
Dept. of IT MESCE Kuttippuram5
Seminar Report ’03 Embedded System in Automobiles
THE DOCTOR WILL SEE YOU NOW
Imagine a time when body transplants like cardiac pacemakers will
be able to monitor and manage themselves remotely. These systems will be
so compact that the patient wouldn’t even be aware that they are embedded
in his body. Another point in favor of RTOSs is their stability, instantaneous
response and efficiency. No OS crashes or delay in responding, as in the case
with most desktop OSes. After all, which patient can rest easy with the
thought of his life literally hanging by a thread due to the time taken by the
OS to load!
Dept. of IT MESCE Kuttippuram6
Seminar Report ’03 Embedded System in Automobiles
Embedded technology advances are pointing towards the use of pace
makers that can be transplanted in or near the heart itself. The pacemaker
will be able to monitor parameters like blood pressure, blood flow, pulse
rate, temperature, etc, using micro sensors planted in various parts of the
body. This capability will enable the pace maker to automatically vary its
operation to suit the changing body conditions. It will also transmit data
using wireless transmission, thus enabling a doctor to constantly monitor its
operation. In most cases, wireless transmitter implanted near the surface of
the skin. In case any abnormality is detected the doctor will be able to take
remedial actions even from a remote location.
Dept. of IT MESCE Kuttippuram7
Seminar Report ’03 Embedded System in Automobiles
WIRED WEARABLES
A mobile phone in the form of a ring or an ear ring? What about
cool sunglasses with streaming video displays built into them? All these can
soon be a reality. Embedded systems have a small foot print and consume
very little power which makes them ideal for wearable computing
applications.The minimal system requirements of these devices ensure that
the hardware is almost microscopic.
IBM is already working on the prototype of a mobile phone that can
be worn as jewellery.The components of the phone will be distributed among
different pieces of jewellery ear ring, necklace, ring and bracelet.
The phone is likely to have blue tooth capability built into it. The
ear rings will have embedded speakers and will act as the receiver. The
necklace will have embedded micro phones that will act as a mouth piece
user can talk into. IBM called the ring part of the phone the decoder ring.
Light emitting diodes (LEDs) will flash to indicate an incoming call. The
ring will also have features that will enable it to be programmed to flash
different colors for a particular user or to indicate the importance of a call. A
video graphics array (VGA) will be built into the bracelet, which will display
the name and phone number of the caller. The bracelet will also integrate the
keypad and the dialing functions in it. IBM plans to incorporate voice
recognition technology for dialing a number. The phone may also have
features to indicate new email.
Dept. of IT MESCE Kuttippuram8
Seminar Report ’03 Embedded System in Automobiles
DON’T KEEP YOUR EYES ON THE ROAD
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.
Dept. of IT MESCE Kuttippuram9
Seminar Report ’03 Embedded System in Automobiles
THE WORKING PRINCIPLE OF ADAPTIVE 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
Dept. of IT MESCE Kuttippuram10
Seminar Report ’03 Embedded System in Automobiles
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.
Dept. of IT MESCE Kuttippuram11
Seminar Report ’03 Embedded System in Automobiles
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
Dept. of IT MESCE Kuttippuram12
Seminar Report ’03 Embedded System in Automobiles
the breaking and the accelerating units. Thus the safe distance will be kept
always. That’s how the ACC works.
ABOUT THE BEAUTY OF ADAPTIVE CRUISE
CONTROL
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
Dept. of IT MESCE Kuttippuram13
Seminar Report ’03 Embedded System in Automobiles
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.
Dept. of IT MESCE Kuttippuram14
Seminar Report ’03 Embedded System in Automobiles
CONCLUSION
Most of the microprocessors in the world are not in pcs, they are
embedded in devices which control traffic for highways, airspace, railway
tracks, and shipping lanes to manufacturing systems with robots. An
embedded system is any device controlled by instructions stored on a chip.
These devices are usually controlled by a microprocessor that executes the
instructions stored on a read only memory (ROM) chip. This the topic of my
seminar. Embedded systems can be used to implement features ranging from
the way pacemakers operate and mobile phone that can be worn as jewellery
to adaptive cruise control(ACC). In this seminar I will explain one such
technology that uses the embedded systems- The Adaptive Cruise Control.
Dept. of IT MESCE Kuttippuram15
Seminar Report ’03 Embedded System in Automobiles
ACKNOWLEDGEMENT
I express my sincere and heartfelt gratitude to
PROF: AGNISHARMAN NAMBOODIRI , Head of Department of
Information Technology and computer science , for giving me an
opportunity to present this seminar. I also express my sincere thanks to
ASSISTANT PROF: SANGEETHA for providing the expert guidance
and help needed for successfully presenting the seminar and for the
completion of this report there after. I also thank profoundly, the services of
Miss. Deepa .S.S. , coordinator of seminar activities. I also thank Ms Anees
Philip, Mr.Lino Varghese, Mrs.Shajila Beegam, Department of
Information Technology , for their guidance in the presentation of this
seminar.
Last but not least, I thank all of my friends who helped me for
the successful presentation of the seminar.
SHAHID MOHAMED
Dept. of IT MESCE Kuttippuram16
Seminar Report ’03 Embedded System in Automobiles
ABSTRACT
Most of the microprocessors in the world are not in pcs, they are
embedded in devices which control traffic for highways, airspace, railway
tracks, and shipping lanes to manufacturing systems with robots. An
embedded system is any device controlled by instructions stored on a chip.
These devices are usually controlled by a microprocessor that executes the
instructions stored on a read only memory (ROM) chip. This the topic of my
seminar. Embedded systems can be used to implement features ranging from
the way pacemakers operate and mobile phone that can be worn as jewellery
to adaptive cruise control(ACC). In this seminar I will explain one such
technology that uses the embedded systems- The Adaptive Cruise Control.
Dept. of IT MESCE Kuttippuram17
Seminar Report ’03 Embedded System in Automobiles
CONTENTS
1. What are embedded systems? 1
2. In the driving seat 4
3. The doctor will see you now 6
4. Wired wearables 8
5. Don’t keep your eyes on the road 9
6. The working principle of Adaptive cruise control 10
7. About the beauty of Adaptive Cruise Control 13
8. Conclusion 15
Dept. of IT MESCE Kuttippuram18