Seminar Report ’03 Automobiles
Embedded System in
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 driverless cars cars that could take us to the destiny by using its its inbu inbuil iltt navi naviga gati tion on syst system ems. s. Embe Embedd dded ed micr microp opro roce cess ssor orss or
micr micro o
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 softwa software re for the embed embedde ded d system system is calle called d firmw firmwar are. e. The firmware will be written in assembly language for time or resource critical opera operatio tions ns or using using higher higher level level langu languag ages es like like C or embed embedde ded d C. The soft softwa ware re will will be simu simula late ted d usin using g micr micro o code code simu simula lato tors rs for for the the targ target et processor. processor. Since
they are supposed to perform perform only specific tasks, these
programs are stored in read only memories(ROMs memories(ROMs).Mor ).Moreover eover they may need no or minimal minimal inputs from from the user, hence hence the user interfa interface ce like monitor, monitor, mouse and large keyboard etc,may be absent.
Embedded Embedded systems are computer systems that monitor, respond to, or contr control ol an exter externa nall envir environm onment ent.. This This envir environm onmen entt is conne connect cted ed 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 connected external
world, but a wide range of
other natural and artificial objects, as well as animals are also possible.
Dept. of IT
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Seminar Report ’03 Automobiles
Embedded System in
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
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Seminar Report ’03 Automobiles •
Embedded System in
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
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MESCE Kuttippuram
Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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 3050 embedded systems within a present-day car. And this is just a beginning.
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Seminar Report ’03 Automobiles
Embedded System in
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!
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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 isthe 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
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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 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
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Seminar Report ’03 Automobiles
Embedded System in
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.
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Seminar Report ’03 Automobiles
Embedded System in
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
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Seminar Report ’03 Automobiles
Embedded System in
ACKNOWLEDGEMENT I PROF:
express
my
sincere
and
heartfelt
gratitude
to
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
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Seminar Report ’03 Automobiles
Embedded System in
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
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Seminar Report ’03 Automobiles
Embedded System in
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
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