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Thursday, October 25, 2012

Electronics and Communivation Engineering

Digital Concurrent Error Detection Schemes Using A Verilog HDL Fault Simulator

1. AIM

This project is concerned with the development of a “Processor” incorporating CED (concurrent error detection) based upon the use of information redundancy(Elliott 1990) (such as the Hamming cod or mode-3 code). The project also makes use of Verilog-HDL to perform fault modelling and simulation in order to assess the effectiveness of the techniques. It is expected that a hardware prototype is developed for targeting to a FPGA with a view to demonstrating the concepts and circuits developed.

2. Introduction

In recent years the utilization of FPGAs extent to systems in space, where the environment is unreliable. This utilization of FPGAs had tremendously increased due to its flexibility, programmability and high-performance capabilities. Systems like DSP, satellite, Mars Rover and reconfigurable radios functions with FPGA. Moreover there are different equipment’s that functions with FPGA are in use and still undeveloped.
     One of the main advantages of FPGAs is its programmable nature. Because of this facility, it has short time-to-market when compared with ASICs. In addition to the above reason, this chip can be easily fabricate, alter and rectify for a designer in a short time. Also Programmable FPGAs help in testing and experimenting new designs, the revenant engineering cost are also reduced.
Here In this project, FPGAs are preferable because of its High performance than processors (McMurtrey 2006). Unlike processors, FPGAs uses dedicated hardware for processing logic and doesn’t require an operating system(Bisen 2010).It also contain thousands of reconfigurable gate array logic circuitry. Another notable difference when comparing CPLDs with FPGAs is the presence in most FPGAs of higher-level embedded functions (such as adders and multipliers) and embedded memories. This adders and multiplier blocks are important in this project because these are the basic function of ALU. Some FPGAs have the capability of partial re-configuration that lets one portion of the device be re-programmed while other portions continue running. (Bisen 2010)

3. Why I intend to do and the relevance

Even though FPFAs has the above mentioned advantages, they are highly affected by radiations(McMurtrey 2006). For example , the highly flexible nature of FPGAs allows the designer to reprogram the chip in the field itself, as well as to correct any post development errors .Remote upgrading is also possible in FPGAS so that different functions can be switched in and out from the base station and the cost is reduced. Since the program is sent to the space for a long period of time, by changing the device configuration, the same chip can work for different variety of functions. In this case the data that are send to the space have a great chance of getting error, which can alter the entire function of the device.

4. What I intent to do, brief summary of activities undertaken

            By considering the above drawbacks, in this project a hardware prototype is developed for targeting to a FPGA which incorporate Information redundancy technique to make the system more reliable and efficient. Some authors(L 1986) had defined these technique of concurrent error detection on VLSI, in that case they had used a residue code over the VLSI design(Elliott 1990). All those design have the disadvantage that they can only detect the errors not correcting. In this design, the system has not only the ability to detect but also to correct the errors, through this its can bring the advantage of low implementation cost in the form of silicon area but the overall speed of the system could be sacrificed.
                  Some of the important activates includes detail study about different encoding/decoding schemes (Hamming code, mode 3), parity codes check-some codes and Berger codes is necessary. Since the implementation should be carried out using Xilinx application it is required to study about how to design FPGA in that. More over some history about FPGA, its basic concept, its advantages, languages used in FPGA and the importance of HDL should be taken in to consideration in this project.In this design ALU is the main part of system where the CED method is introduced, the aim is to develop 32 bit ALU which can process multiplication into it, to make the system more advance. The last but the most important activity is to programme a fault injection simulator. While simulating the hardware with the fault injector it will corrupt a logic gate or configuration bit and it will be evaluated whether the hardware can detect and correct the error.

5. How to proceed and the methods that should follow to attain the aim ?

The main part of this project is to design ALU and to introduce an error correction/detection scheme into that. Here in this design Hamming code technique are developed into a 32 bit ALU structure as shown in the figure, where it capable of not only detecting but also to correct the errors. The main reason for choosing hamming code is because of its ease of implementation and the checking elements are very small(Elliott 1990).
The schematic shown belowconsists of an information processing section and a parityprocessing section; a word size of 8 bits was chosen forthis implementation of the information section, thereforethe number of parity bits required for a SEC/DEDHamming code is 5. 

6. Hamming code Error Detection/correction

Error detection code is a method of encoding the data bit with parity bits, so that the error can be detected .For example the simplest error detection code is the 1-bit code. In this code, a single parity bit is added to n data bits, which is 1 if the odd number of data bits are 1s,0 otherwise. SO that the total number of 1s in the parity checked bits, including parity bits, should always be even. Suppose if there is any error it will produce odd number of 1 bits in the word.
 Hamming codes can also be used to correct single errors. Supose a code word X is transmitted, then the received wordis  ,where E is the error vector. In this case if there is no error then E will be zero; else if there is a single error then E is a vector with exactly one 1 and the rest 0s. We check a received matrix by multiplying by the parity-check matrix.

7. Arithmetic operations

The parity of the result for the addition of two numbersis given by
where , are the parity bits generated from the carriesof the addition operation.

+ represents carry in. The carry out from column 8 is not used in the generation of
(Elliott 1990). Both and depend on the information bits beingsupplied to the information ALU and so two Hammingencoders are required within the information processingsection of the datapath to generate the and signals; these are located within the Auxiliary ALU( ). The encoders along with the checking and correctinghardware constitute the two points of interactionbetween the information and parity sections of the datapath,otherwise both sections operate independently.


  • The main functional objectives of this project is demonstrating and evaluating CED/CEC technique using FPGA. The other objectives of this project includes
  •  To analyse the important characteristics of various coding techniques that could be used for error control in a FPGA to make it reliable.
  •  To study different coding techniques (likeHamming codes andmode-3 code)and the various methods used for encoding and decoding of the codes to achieve efficient detection and correction of the errors.
  •  Analysis of the simulation results of the Hamming encoder and decoder using a Model sim.
  • To create a Hardware prototype using FPGA, that can detect and correct errors in ALU using Verilog-HDL.
  • Hardware prototype is developed using FPGA in order to demonstrate the concept of CED its correction and the circuit developed.
  • To evaluate the speed of the hardware and the area overhead required after introducing CED/CEC techniques.


·         FPGA kit
·         Xilinx
·         Model Sim

         10.  Reference

       Finished.....PLease leave your questions as comment............

       If you need help in any programming section in verilog,, pplz contact

Wednesday, August 13, 2008



Every day of your computing life, you reach out for the mouse whenever you want to move the cursor or activate something. The mouse senses your motion and your clicks and sends them to the computer so it can respond appropriately. An ordinary mouse detects motion in the X and Y plane and acts as a two dimensional controller. It is not well suited for people to use in a 3D graphics environment. Space Mouse is a professional 3D controller specifically designed for manipulating objects in a 3D environment. It permits the simultaneous control of all six degrees of freedom - translation rotation or a combination. . The device serves as an intuitive man-machine interface

  The predecessor of the spacemouse was the DLR controller ball. Spacemouse has its origins in the late seventies when the DLR (German Aerospace Research Establishment) started research in its robotics and system dynamics division on devices with six degrees of freedom (6 dof) for controlling robot grippers in Cartesian space. The basic principle behind its construction is mechatronics engineering and the multisensory concept. The space mouse has different modes of operation in which it can also be used as a two-dimensional mouse.

How does computer mouse work?
Mice first broke onto the public stage with the introduction of the Apple Macintosh in 1984, and since then they have helped to completely redefine the way we use computers. Every day of your computing life, you reach out for your mouse whenever you want to move your cursor or activate something. Your mouse senses your motion and your clicks and sends them to the computer so it can respond appropriately
2.1 Inside a Mouse
The main goal of any mouse is to translate the motion of your hand into signals that the computer can use. Almost all mice today do the translation using five components: 
  Fig.1 The guts of a mouse
1. A ball inside the mouse touches the desktop and rolls when the mouse moves. 
Fig 2
The underside of the mouse's logic board: The exposed portion of the ball touches the desktop.

2. Two rollers inside the mouse touch the ball. One of the rollers is oriented so that it detects motion in the X direction, and the other is oriented 90 degrees to the first roller so it detects motion in the Y direction. When the ball rotates, one or both of these rollers rotate as well. The following image shows the two white rollers on this mouse:
Fig.3 The rollers that touch the ball and detect X and Y motion
3. The rollers each connect to a shaft, and the shaft spins a disk with holes in it. When a roller rolls, its shaft and disk spin. The following image shows the disk:  
Fig.4 A typical optical encoding disk: This disk has 36 holes around its outer edge.

4. On either side of the disk there is an infrared LED and an infrared sensor. The holes in the disk break the beam of light coming from the LED so that the infrared sensor sees pulses of light. The rate of the pulsing is directly related to the speed of the mouse and the distance it travels. 

Fig.5 A close-up of one of the optical encoders that track mouse motion: There is an infrared LED (clear) on one side of the disk and an infrared sensor (red) on the other.

5. An on-board processor chip reads the pulses from the infrared sensors and turns them into binary data that the computer can understand. The chip sends the binary data to the computer through the mouse's cord.

Fig 6 The logic section of a mouse is dominated by an encoder chip, a small processor that reads the pulses coming from the infrared sensors and turns them into bytes sent to the computer. You can also see the two buttons that detect clicks (on either side of the wire connector).
 In this optomechanical arrangement, the disk moves mechanically, and an optical system counts pulses of light. On this mouse, the ball is 21 mm in diameter. The roller is 7 mm in diameter. The encoding disk has 36 holes. So if the mouse moves 25.4 mm (1 inch), the encoder chip detects 41 pulses of light. 
 Each encoder disk has two infrared LEDs and two infrared sensors, one on each side of the disk (so there are four LED/sensor pairs inside a mouse). This arrangement allows the processor to detect the disk's direction of rotation. There is a piece of plastic with a small, precisely located hole that sits between the encoder disk and each infrared sensor. This piece of plastic provides a window through which the infrared sensor can "see." The window on one side of the disk is located slightly higher than it is on the other -- one-half the height of one of the holes in the encoder disk, to be exact. That difference causes the two infrared sensors to see pulses of light at slightly different times. There are times when one of the sensors will see a pulse of light when the other does not, and vice versa.


3.1 What is Mechatronics engineering?

Mechatronics is concerned with the design automation and operational performance of electromechanical systems. Mechatronics engineering is nothing new; it is simply the applications of latest techniques in precision mechanical engineering, electronic and computer control, computing systems and sensor and actuator technology to design improved products and processes.

The basic idea of Mechatronics engineering is to apply innovative controls to extract new level of performance from a mechanical device. It means using modem cost effective technology to improve product and process performance, adaptability and flexibility.

Mechatronics covers a wide range of application areas including consumer product design, instrumentation, manufacturing methods, computer integration and process and device control. A typical Mechatronic system picks up signals processes them and generates forces and motion as an output. In effect mechanical systems are extended and integrated with sensors (to know where things are), microprocessors (to work out what to do), and controllers (to perform the required actions).

The word Mechatronics came up describing this fact of having technical systems operating mechanically with respect to some kernel functions but with more or less electronics supporting the mechanical parts decisively. Thus we can say that Mechatronics is a blending of Mechanical engineering,
Electronics engineering and Computing
These three disciplines are linked together with knowledge of management, manufacturing and marketing.

3.2 What do Mechatronics engineers do?

Mechatronics design covers a wide variety of applications from the physical integration and miniaturization of electronic controllers with mechanical systems to the control of hydraulically powered robots in manufacturing and assembling factories. 

Computer disk drives are one example of the successful application of Mechatronics engineering as they are required to provide very fast access precise positioning and robustness against various disturbances. 

An intelligent window shade that opens and closes according to the amount of sun exposure is another example of a Mechatronics application. 

Mechatronics engineering may be involved in the design of equipments and robots for under water or mining exploration as an alternative to using human beings where this may be dangerous. In fact Mechatronics engineers can be found working in a range of industries and project areas including
• Design of data collection, instrumentation and computerized machine tools.
• Intelligent product design for example smart cars and automation for household transportation and industrial application.
• Design of self-diagnostic machines, which fix problems on their own.
• Medical devices such as life supporting systems, scanners and DNA sequencing automation.
• Robotics and space exploration equipments.
• Smart domestic consumer goods
• Computer peripherals.
• Security systems.

3.3 Mechatronic goals

3.3.1 The multisensory concept

The aim was to design a new generation of multi sensory lightweight robots. The new sensor and actuator generation does not only show up a high degree of electronic and processor integration but also fully modular hardware and software structures. Analog conditioning, power supply and digital pre-processing are typical subsystems modules of this kind. The 20khz lines connecting all sensor and actuator systems in a galvanically decoupled way and high speed optical serial data bus (SERCOS) are the typical examples of multi sensory and multi actuator concept for the new generation robot envisioned. 

The main sensory developments finished with these criteria have been in the last years: optically measuring force-torque-sensor for assembly operations. In a more compact form these sensory systems were integrated inside plastic hollow balls, thus generating 6-degree of freedom hand controllers (the DLR control balls). The SPACE-MOUSE is the most recent product based on these ideas.
• stiff strain-gauge based 6 component force-torque-sensor systems.
• miniaturized triangulation based laser range finders.
• integrated inductive joint-torque-sensor for light-weight-robot.

In order to demonstrate the multi sensory design concept, these types of sensors have been integrated into the multi sensory DLR-gripper, which contains 15 sensory components and to our knowledge it is the most complex robot gripper built so far (more than 1000 miniaturized electronic and about 400 mechanical components). It has become a central element of the ROTEX space robot experiment.


Spacemouse is developed by the DLR institute of robotics and mechatronics.
DLR- Deutsches Zenturum far Luft-und Raumfahrt

4.1 Why 3D motion?

In every area of technology, one can find automata and systems controllable up to six degrees of freedom- three translational and three rotational. Industrial robots made up the most prominent category needing six degrees of freedom by maneuvering six joints to reach any point in their working space with a desired orientation. Even broader there have been a dramatic explosion in the growth of 3D computer graphics.

 Already in the early eighties, the first wire frame models of volume objects could move smoothly and interactively using so called knob-boxes on the fastest graphics machines available. A separate button controlled each of the six degrees of freedom. Next, graphics systems on the market allowed manipulation of shaded volume models smoothly, i.e. rotate, zoom and shift them and thus look at them from any viewing angle and position. The scenes become more and more complex; e.g. with a "reality engine" the mirror effects on volume car bodies are updated several times per second - a task that needed hours on main frame computers a couple of years ago. 

Parallel to the rapid graphics development, we observed a clear trend in the field of mechanical design towards constructing and modeling new parts in a 3D environment and transferring the resulting programs to NC machines. The machines are able to work in 5 or 6 degrees of freedom (dot). Thus, it is no surprise that in the last few years, there are increasing demands for comfortable 3D control and manipulation devices for these kinds of systems. Despite breathtaking advancements in digital technology it turned out that digital man- machine interfaces like keyboards are not well suited for people to use as our sensomotory reactions and behaviors are and will remain analogous forever.

4.2 DLR control ball, Magellan's predecessor

At the end of the seventies, the DLR (German Aerospace Research Establishment) institute for robotics and system dynamics started research on devices for the 6-dof control of robot grippers .in Cartesian space. After lengthy experiments it turned out around 1981 that integrating a six axis force torque sensor (3 force, 3 torque components) into a plastic hollow ball was the optimal solution. Such a ball registered the linear and rotational displacements as generated by the forces/ torques of a human hand, which were then computationally transformed into translational / rotational motion speeds. 

The first force torque sensor used was based upon strain gauge technology, integrated into a plastic hollow ball. DLR had the basic concept centre of a hollow ball handle approximately coinciding with the measuring centre of an integrated 6 dof force / torque sensor patented in Europe and US.

  From 1982-1985, the first prototype applications showed that DLR's control ball was not only excellently suited as a control device for robots, but also for the first 3D-graphics system that came onto the market at that time. Wide commercial distribution was prevented by the high sales price of about $8,000 per unit. It took until 1985 for the DLR's developer group to succeed in designing a much cheaper optical measuring system.

4.2.1 Basic principle

The new system used 6 one-dimensional position detectors. This system received a worldwide patent. The basic principle is as follows. The measuring system consists of an inner and an outer part. The measuring arrangement in the inner ring is composed of the LED, a slit and perpendicular to the slit on the opposite side of the ring a linear position sensitive detector (PSD). The slit / LED combination is mobile against the remaining system. Six such systems (rotated by 60 degrees each) are mounted in a plane, whereby the slits alternatively are vertical and parallel to the plane. The ring with PSD's is fixed inside the outer part and connected via springs with the LED-slit-basis. The springs bring the inner part back to a neutral position when no forces / torque are exerted: There is a particularly simple and unique. This measuring system is drift-free and not subject to aging effects. 

The whole electronics including computational processing on a one-chip-processor was already integrable into the ball by means of two small double sided surface mount device (SMD) boards, the manufacturing costs were reduced to below $1,000, but the sales price still hovered in the area of $3,000. 

The original hopes of the developers group that the license companies might be able to redevelop devices towards much lower manufacturing costs did not materialize. On the other hand, with passing of time, other technologically comparable ball systems appeared on the market especially in USA. They differed only in the type of measuring system. Around 1990, terms like cyberspace and virtual reality became popular. However, the effort required to steer oneself around in a virtual world using helmet and glove tires one out quickly. Movements were measured by electromagnetic or ultrasonic means, with the human head having problems in controlling translational speeds. In addition, moving the hand around in free space leads to fairly fast fatigue. Thus a redesign of the ball idea seemed urgent.

4.3 Magellan (the European Spacemouse):
the result of a long development chain

With the developments explained in the previous sections, DLR's development group started a transfer company, SPACE CONTROL and addressed a clear goal: To redesign the control ball idea with its unsurpassed opto electronic measuring system and optimize it thus that to reduce manufacturing costs to a fraction of its previous amount and thus allow it to approach the pricing level of high quality PC mouse at least long-term. 


Spacemouse system

The new manipulation device would also be able to function as a conventional mouse and appear like one, yet maintain its versatility in a real workstation design environment. The result of an intense one-year's work was the European SpaceMouse, in the USA it is especially in the European market place. But end of 93, DLR and SPACE CONTROL jointly approached LOGITECH because of their wide expertise with pointing devices for computers to market and sell Magellan in USA and Asia. The wear resistant and drift free opto electronic, 6 component measuring system was optimized to place all the electronics, including the analogous signal processing, AT conversion, computational evaluation and power supply on only one side of a tiny SMD- board inside Magellan's handling cap. It only needs a few milliamperes of current supplied through the serial port of any PC or standard mouse interface. It does not need a dedicated power supply. The electronic circuitry using a lot of time multiplex technology was simplified by a factor of five, compared to the former control balls mentioned before. The unbelievably tedious mechanical optimization, where the simple adjustment of the PSD's with respect to the slits played a central role in its construction, finally led to 3 simple injection moulding parts, namely the basic housing, a cap handle with the measuring system inside and the small nine button keyboard system. The housing, a punched steel plate provides Magellan with the necessary weight for stability; any kind of metal cutting was avoided. The small board inside the cap (including a beeper) takes diverse mechanical functions as well. For example, it contains the automatically mountable springs as well as overload protection. The springs were optimized in the measuring system so that they no longer show hysteresis; nevertheless different stiffness of the cap are realizable by selection of appropriate springs. Ergonomically, Magellan was constructed as flat as can be so that the human hand may rest on it without fatigue. Slight pressures of the fingers on the cap of Magellan is sufficient for generating deflections in X, Y, and Z planes, thus shifting a cursor or flying a 3D graphics object translationally through space. Slight twists of the cap cause rotational motions of a 3D graphics object around the corresponding axes. Pulling the cap in the Z direction corresponds to zooming function. Moving the cap in X or Y direction drags the horizontally and vertically respectively on the screen. Twisting the cap over one of the main axes or any combination of them rotates the object over the corresponding axis on the screen. The user can handle the object on the screen a he were holding it in his own left hand and helping the right hand to undertake the constructive actions on specific points lines or surfaces or simply by unconsciously bringing to the front of appropriate perspective view of any necessary detail of the object. With the integration of nine additional key buttons any macro functions can be mapped onto one of the keys thus allowing the user most frequent function to be called by a slight finger touch from the left hand. The device has special features like dominant mode. It uses those degrees of freedom in which the greatest magnitude is generated. So defined movements can be created. Connection to the computer is through a 3m cable (DB9 female) and platform adapter if necessary. Use of handshake signals (RTSSCTS) are recommended for the safe operation of the spacemouse. Without these handshake signals loss of data may occur. Additional signal lines are provided to power the Magellan (DTS&RTS). Thus, no additional power supply is needed. Flying an object in 6 dof is done intuitively without any strain. In a similar way, flying oneself through a virtual world is just fun. Touching the keys results in either the usual menu selection, mode selection or the pickup of 3D objects.

Fig.8 Spacemouse

 Table-1 Technical specifications of spacemouse 


5.1 Features 

• Ease of use of manipulating objects in 3D applications.
• Calibration free sensor technology for high precision and unique reliability.
• Nine programmable buttons to customize users preference for motion control
• Fingertip operation for maximum precision and performance.
• Settings to adjust sensitivity and motion control to the users preference.
• Small form factor frees up the desk space.
• Double productivity of object manipulation in 3D applications.
• Natural hand position (resting on table) eliminates fatigue.

5.2 Benefits

As the user positions the 3D objects with the Magellan device the necessity of going back and forth to the menu is eliminated. Drawing times is reduced by 20%-30% increasing overall productivity. With the Magellan device improved design comprehension is possible and earlier detection of design errors contributing faster time to market and cost savings in the design process. Any computer whose graphics power allows to update at least 5 frames per second of the designed scenery, and which has a standard RS232 interface, can make use of the full potential of Magellan spacemouse. In 3D applications Magellan is used in conjunction with a 2D mouse. The user positions an object with spacemouse while working on the object using a mouse. We can consider it as a workman holding an object in his left hand and working on it with a tool in his right hand. Now Magellan spacemouse is becoming something for standard input device for interactive motion control of 3D graphics objects in its working environment and for many other applications.



Magellan's predecessor, DLR's control ball, was a key element of the first real robot inspace, ROTEX- (3), which was launched in April 93 with space shuttle COLUMBIA inside a rack of the spacelab-D2. The robot was directly teleoperated by the astronauts using the control ball, the same way remotely controlled from ground (on-line and off line) implying "predictive" stereographics. As an example, the ground operator with one of the two balls or Magellans steered the robot's gripper in the graphics presimulation, while with the second device he was able to move the whole scenery around smoothly in 6 dot Predictive graphics simulation together with the above mentioned man machine interaction allowed for the compensation of overall signal delays up to seven seconds, the most spectacular accomplishment being the grasping of a floating object in space from the ground. Since then, ROTEX has often been declared as the first real "virtual reality" application.


  A most intuitive controlling device would be a system that can be instructed by watching and imitating the human user, using the hand as the major controlling element. This would be a very comfortable interface that allows the user to move a robot system in the most natural way. This is called the visual space mouse. The system of the visual space mouse can be divided into two main parts: image processing and robot control. The role of image processing is to perform operations on a video signal, received by a video camera, to extract desired information out of the video signal. The role of robot control is to transform electronic commands into movements of the manipulator. 


The graphics simulation and manipulation of 3D volume objects and virtual worlds and their combination e.g. with real information as contained in TV images (multi-media) is not only meaningful for space technology, but will strongly change the whole world of manufacturing and construction technology, including other areas like urban development, chemistry, biology, and entertainment. For all these applications we believe there is no other man- machine interface technology comparable to Magellan in its simplicity and yet high precision. It is used for 3D manipulations in 6 dof, but at the same time may function as a conventional 2D mouse.


(1) J. HeintB, G. Hilzinger  
Device for programming movements of a Robot, Enrop. Patent No. 0.108.348; US-Patent No. 4,589,810

(2) J. Dietrich, G. Plank, H. Krans
Optoelectronic System Housed in Plastic Sphere,
Emop. Patent No. 0 240 023; US-Patent No. 4,785,180; JP-Patent No. 1763 620

(3) G. Hirzmger and J. Dietrich, B. Gombert, J. Heindi, K. Landzettel, J. Schott
The sensory and telerobotic aspects of the spare robot technology experiment ROTEX,
Int. Symposium "Artificial Intelligence, Robotics and Automation, in Space",
Toulouse Labege, France, Sept. 30 - Oct. 2, 1992.




  Space mouse opens a new age for man-machine communication. This device is based on the technology used to control the first robot in space and has been adapted for a wide range of tasks including mechanical design, real time video animation and visual simulation. It has become a standard input device for interactive motion control of three-dimensional graphic objects in up to six degrees of freedom. Space mouse works with standard serial mouse interface without an additional power supply. The ergonomic design allows the human hand to rest on it without fatigue. Thus flying an object in six degrees of freedom is done without any strain.

I express my sincere gratitude to Dr. Agnisarman Namboodiri, Head of Department of Information Technology and Computer Science , for his guidance and support to shape this paper in a systematic way.

I am also greatly indebted to Mr. Saheer H. and 
Ms. S.S. Deepa, Department of IT for their valuable suggestions in the preparation of the paper.

In addition I would like to thank all staff members of IT department and all my friends of S7 IT for their suggestions and constrictive criticism.


  4.1 WHY 3D MOTION 9 


  Remote controlled Fan Regulator

  Remote controlled Fan Regulator is one of the applications of electronics to increase the facilities of life. Fan is one of the unavoidable Electronic equipment in our day today life. It ahs become essential element without which people can’t lead a smooth life. The presence of a fan in a house or office is not now considered as a luxury on the other hand it is included in the basic requirement. The use of new electronic theories have been put down by expertise to increase the facilities given by the existing appliance. Here the facility of ordinary fan is increased by the making it controlled by a remote.                                                                                                              
 In remote controlled fan regulator we can regulate the speed of the fan by using a remoter control. Here the variation in the firing angle of triac is used for regulating the speed. In this 2 NE 555 IC is wired as Monostable multivibrator. MOC 3021 act as optoisolater there is a decade counter CD 4017. For varying firing angle there is a Triac BT 136. For regulating the input AC supply there is a regulator Section consisting of IC 7809 and transformer (12 V0- 12 V). For receiving IR signal TSO P1738 is used.

Any button on the remote can be used for controlling speed of the fan. Using this circuit, we can change the speed of the fan from our couch or bed. This circuit is used for controlling this speed of the fan in 5 levels. This innovating can be success only if people are made aware about its advantages and how uses friendly it is. The circuit can be used to regulate the intensity of light. This innovation finds its use mainly to help oldage people who doesn’t want. To walk in order to control he speed of fan. It also finds its use of somebody wants to change the speed while sleeping. They don’t want to go out of the bed.


  A circuit that allows total control over your equipments without having to move around is a revolutionary concept. Total control over the speed of the fan is a boon to many. This product brings to you this very concept.

 Remote control facilitates the operation of fan regulators around the home or office from a distance. It provides a system that is simple to understand and also to operate, a system that would be cheap and affordable, a reliable and easy to maintain system of remote control and durable system irrespective of usage. It adds more comfort to everyday living by removing the inconvenience of having to move around to operate a fan regulator. The system seeks to develop a system that is cost effective while not under mining the need for efficiency.

 The first remote control, called “lazy bones” was developed in 1950 by Zenith Electronics Corporation (then known as Zenith Radio Corporation). The device was developed quickly, and it was called “Zenith space command”, the remote went into production in the fall of 1956, becoming the first practical wireless remote control device.

Today, remote control is a standard on other consumer electronic products, including VCRs, cable and satellite boxes, digital video disc players and home audio players. And the most sophisticated TV sets have remote with as many as 50 buttons. In year 2000, more than 99 percent of all TV set and 100 percent of all VCR and DVD players sold are equipped with remote controls. The average individual these days probably picks up a remote control at least once or twice a day.

Basically, a remote control works in the following manner. A button is pressed. This completes a specific connection which produces a Morse code line signal specific to that button. The transistor amplifies the signal and sends it to the LED which translates the signal into infrared light. The sensor on the appliance detects the infrared light and reacts appropriately.

The remote control’s function is to wait for the user to press a key and then translate that into infrared light signals that are received by the receiving appliance. The carrier frequency of such infrared signals is typically around 36 kHz .
One of the primary objectives of an engineer is to endeavor to deliver the best product or the most efficient services at the lowest cost to the end user. The system was found to meet the expected results.

The aim of this work is to design and construct a remote control for a fan regulator.. The remote control device sends an infra-red beam, which is received by the infra-red sensor on the regulator and the fan also increases in speed.



Infrared Receiver Module:
 Here TSOP 1738 is used as infrared receiver Module. The infrared rays transmitted by the remote control in received by TSOP 1738. it is capable of receiving signals upto 38 Khz.

Monostable Multivibrator:
 Here NE 555 IC is wired as monostable multivibrator. The trigger to this is signals from receiver module. Monostable multivibrator is used forgetting a accurate pulse.

Decade Counter:
 CD 4017 is used as decade counter. Here actually ten outputs are there from which five are used (Q0 to Q4), Q5 is not used and Q6 is used to reset. The output of monostble is used to delay the clock pulse of decade counter.

Regulator Section:
 The 230 V Ac us step down to 12 V by transformer (12V-0-12V). This 12V is regulated wring IC 7809 to 9V. This 9V is supplied to the whole circuit.

Opto Coupler:
 MCT2E is used as optocoupler. It is used to trigger the monostable multivibrator.

Opto Isolator:
 MOC 3021 is used as opto isolator. It is used to drive the Triac BT 136.

Triac BT 136:
 It is thyristor with a firing angle nearly 450. A snubber circuit consisting of a resistor and capacitor is used to control the firing angle of Triac. This firing angle determines the speed of the fan.



  The 230 V from AC mains is stepped down to 12V and Regulated by IC 7809 and, capacitor and Diodes to 9V. This filtered 9V is used for proceeding supply to the entire circuit. Any button of remote control can be used to control the speed of the fan. The remote control produces infrared rays which is received by the TSOP infrared receives module. The TSOP used here is TSOP 1738. It is capable for receiving signals up to 38 KHZ. The infrared rays received by the TSOP senses it and its output is wired as a trigger to the first monostable multivibrator NE 555 through a LED and Resistor R4.

 This NE 555 which is wired as Monostable multivibrator is used to delay the clock to decade counter which is CD 4017. We can directly give the output of TSOP to decade counter, but white doing so all the small pulse or noises may also act a clock to counter and counter starts counting. The decade counter has ten outputs from Q0 to Q9. But here we are using only Q0 to Q4. Q5 is not used and Q6 is used to reset the counter. The outputs of decade counter is taken through Resistors R5 to R9. The resistor Rs to R9 and capacitor C5 controls the pulse width which is actually determining the speed of the fan high capacitor C% is charged through R6 and so on. Here we are controlling the speed of the fan.

 When the output of Q0 is high the capacitor C5 is charged through R5, if Q1 is high capacitor C5 is charged through R6 and so on. Here we are controlling the speed of the fan in five levels that is why we are taking five outputs (A0 to Q4).

 Another NE 555 used here which is also wired as monostable multivibrator. This monostable is triggered by pulses from out coupler MCT 2E. It is wired as Zero crossing detector. The output from decade counter is given to NE555 and this is given to the transistor BC 548 it is given to the Opto isolator MOC 3021. It is used for driving the Triac BT 136. Triac is a type of thyristor. Here the resistor R13 (470hm) and capacitor C7 (0.01µF) combination is used as snubber network for the Triac.

 By the controlling done by Resistors R5 to R9 and capacitor C5 we can control the pulse width. When Q0 output is high the pulse width is maximum, when Q1 output is high pulse width is decreased slightly. As the pulse width decreases firing angle of the triac increases and speed of the fan also increases. By using remote control we are actually controlling pulse width which in turn vary the firing angle of triac, which inturn vary the speed of the fan.


1. TSOP 1738
2. IC NE 555
4. IC MOC 3021
5. IC 7809
6. IC CD4017
8. LED
 . IN4148
 . IN 4007
11. TRIAC BT 136
0.01 µF /400V
4.7 µF /16V
10 µF /16V
1 µF /16V
470 µ /50V

  47K Ω
  470 Ω
  5.6 K
  10 K
  47 Ω



 Printed circuits boards play a vital role here in determining the overall performance of electronic equipment .A good PCB design ensures that the noise introduced as a result of component placement and track layout is held within limits while still providing components years of assembly maintenance and performance reliability.


 Printed circuits boards are used to route electric signals through copper track which are firmly bonded to an insulating base.
 Advantages of PCB over common wiring are:
1. PCB’s are necessary for connecting a large number of electronic components in a very small area with minimum parasitic effects.
2. PCB’s are simulated with mass production with less chance of writing error
3. Small components are easily mounted.
4. Servicing in simplified.

The base materials used for PCB’s are glass epoxy, epoxy paper, polyester etc.Copper foil used for copper clad is manufactured by the process of electronic deposition .The properties of copper foil are:
  Thickness………………35μ meter
  Thickness tolerance……+5 μ meter
  Purity of Copper………99.8%
  Resistivity at 20◦C…….0.1594

  In a single sided PCB the conductor tracks run only on one side of copper clad board. Thus crossing of conductors is not allowed. Base materials are selected according to application. It is mechanically and chemically cleansed. Then the photo resist is an organic solution which when exposed to light of proper wavelength, changes their solubility in developer but after exposure to light is not soluble. Laminate coating of photo resist is done by (i)spray coating (ii)Dip coating (iii)Roller coating. The coated copper clad and laminated film negative is kept in intimate contact with each other.

  The assembly is exposed to UV light and exposed board is rinsed in the developer tank. Proper developer has to be used for a particular photo resist and

then the PCB is dyed in a tray. The dye reveals the flux to be used for a particular photo resist. Then the PCB is dyed in a tray.

    The layout can be done either by hand or by using PCB designing software like ORCAD or PROTEL.

   The required circuit is designed and the layout of the circuit is done on the component side as well as the copper clad side. Spaces are provided for holes to insert the respective components. Etch resistant ink coatings are given on the interconnecting marks.

 The copper clad PCB is etched with ferric chloride solution containing a small amount of Hydro Chloric Acid for increasing activeness of Ferric Chloride in etching. Wherever the varnish coating is there the copper remains. Then it is washed with water and Oxalic Acid

 The required holes are drilled using twist drill. Now the PCB is complete and ready for soldering.

  Soldering is the process of joining of two metals using an alloy solder consisting of Tin and Lead (Sn-Pb). Tin determines the melting whereas the Lead is used to reduce the cost. After the PCB fabrication is done, the various components are arranged at proper locations on the PCB and then the soldering is done.
  All liquids consist of particles which attract each other. The surface is always is trying to shrink and this is because of surface tension. The principle behind soldering is that when liquid particles are brought in contact with the walls of the solid surface, it may happen that the solid attracts the liquid surface. This property is called adhesive property. Care must be taken that the melting point of solder is below that of the metal so that its surface is melted without melting without the metal.

During the soldering process the flux acts as a medium for improving the degree of melting. The basic functions of flux are mentioned below:
1. Removes oxide from the surface.
2. Assists the transfer of heat from the source to the joining and provides a liquid cover including air gap.
3. Removal of residue after the completion of the soldering operation.







 Remote controlled Fan Regulator is used to control the speed of fan from our bed or couch. The same circuit finds its use to control the Intensity of light at fire levels. So it can be used as night lamps. This circuit also finds it use for switching ON and OFF any electronic circuit.



 This circuit is simple to use and efficient. It can be assembled with ease. It is cheap and hence and very economic. It is small in size and can be fixing inside the fan.


  The one and only one disadvantage of the circuit is that speed can be increased only in one direction. It can’t be decreased.


 With the knowledge of new techniques in ‘Electronics’ we are able to make our life more comfortable one such application of electronics is used in “REMOTE CONTROLLED FAN REGULATOR”.

  This same circuit find its use in many more applications. By this the intensity of light can be controlled using remote control. The intensity of light can be controlled in five levels from off position to maximum intensity possible. So it finds its use as night lamp by keeping the intensity of lamp in low level.

 The circuit also finds its use for switching ON and OFF any electronic circuitry. Our normal T.V remote can be used for controlling speed of fan or intensity of light. So it is very useful or a real help to oldage and sick people, since they can control the speed from the place where they are sitting.

 We feel that our product serves something good to this world and we like to present it before this prosperous world.


• Linear Integrated circuit – By Gaykwad



Mini Project Report

Submitted in partial fulfillment of the requirements
for the award of B.Tech Degree in
Electronics & Communication Engineering

MAY 2008

Department of Electronics & Communication Engineering


(An ISO 9001 Certified Institution)
  Certified that this is a Bonafide Record of the Mini Project entitled “Remote Controlled Fan Regulator” submitted by RONEY JOSEPH during the year 2008 in partial fulfillment for the award of Bachelor of Technology in Electronics & Communication Engineering.
  Register No:17241
  Branch: Electronics and Communication.
HOD In-charge

Internal examiner External examiner

Place: Kalady

 I take this opportunity to express my deep sense of gratitude and profound respect to all those who have guided and inspired me for the project work.
  First and foremost, I extend my deep gratitude to Dr.S.G.Iyer,Principal, ASIET for granting me permission to undertake this project. I express my sincere thanks to Mr Venugopalan k HOD, Electronics And Communication for giving me an opportunity to utilize all the resources required for the completion of my project.

  I am deeply indebted to my project guides Mrs Rathi, Mrs Sindhu ,Mrs Megha and Mr Sreekanth Electronics Department for their guidance, timely advice and support rendered during all stages of the project work.
 I express my whole hearted gratitude to them. I express my thanks to Mrs Supriya, Lab Assistant, for her valuable assistance during the course of my work.

  Finally, I convey my thanks to my parents and friends who have directly or indirectly helped me in the successful completion of the project.