www.final-yearproject.com | www.finalyearthesis.com Hand Gesture Based Wireless Controlled RobotA report submittedIn partial fulfillment of the requirements for the degree ofBachelor Of Technology InElectronics and Communication Engineering

Submitted By

Sangam Khare ( 0910331064)

Under the supervision of Ms. Shipra Saini Senior Lecturer

Department of Electronics & Communication Engineering

Shobhit Institute of Engineering & Technology, Saharanpur (U.P.)

Gautam Buddh Technical University, Lucknow

UNDERTAKING

We declare that the project work presented in this report entitled Topic, submitted to the department of electronics and communication, Shobhit Institute of Engineering and technology, Saharanpur, for the award of Bachelor of Technology degree in Electronics and Communication Engineering from Gautam Budhh Technical University, Lucknow is our original work. The contents of the report do not form the basis for the award of any other degree to the candidate or to anybody else from this or any other University/Institution. Further we have not plagiarized or submitted the same work for the award of any other degree. In this case undertaking is found incorrect, we accept that our degree may unconditionally be withdrawn.

May..., 2013 S.I.E.T.,Gangoh Name of students: Sangam Khare (0910331064)

Certificate

Certified that Sangam Khare (0910331064), has carried out the project work presented in this report entitled Hand Gesture Based Wireless Controlled Robot for the award of Bachelor of Technology in Electronic & Communication from Gautam Buddh Technical University, Lucknow under my supervision. The report embodies results of original work, and studies are carried out by the student himself and the contents of the report do not form the basis for the award of any other degree to candidate or to anybody else from this or any other University/Institution.

Supervisor (Ms. Shipra Saini) SeniorLecturer Dept. of Electronics &CommunicationEngineering Shobhit Institute of Engineering & Technology Saharanpur- 247001, Uttar Pradesh, India Date: ..

Acknowledgement

We wish to take this opportunity to express my deep sense of gratitude and thanks to our head of department and supervisor. We are thankful; to all faculty member and lab staff member of the department who helped me directly or indirectly in completing the work. Last, but not the least, We are thankful to the management members and director of Shobhit Institute of Engineering and Technology, Saharanpur (U.P.) who permitted and supported us for completing this project work.

Project associates: Sangam Khare (0910331064)

ABSTRACTThe main objective of our project work is to control a robot with gestures of our hand. There are two main components of our system: Arduino microcontroller AccelerometerThe accelerometer depends upon the gestures of our hand. Through accelerometer, a passage of data signal is received and it is processed with the help of arduino microcontroller. The microcontroller gives command to the robot to move in the desired direction. The basic working principle for our robot is passage of the data signals of accelerometer readings to the Arduino board fitted on the bot. The program compiled in that arduino runs according to that value, which make the bot function accordingly .While we have used two-axis accelerometer. In which, one axis will control the speed in forward or backward direction and other axis will control the turning mechanism. Accelerometer-based gesture control is studied as a supplementary or an alternative interaction modality. Gesture commands freely trainable by the user can be used for controlling external devices with handheld wireless sensor unit. Two user studies are presented. The first study concerns finding gestures for controlling a design environment (Smart Design Studio), TV, VCR, and lighting. The results indicate that different people usually prefer different gestures for the same task, and hence it should be possible to personalise them. The second user study concerns evaluating the usefulness of the gesture modality compared to other interaction modalities for controlling a design environment. The other modalities were speech, RFID-based physical tangible objects, laser-tracked pen. The results suggest that gestures are a natural modality for certain tasks, and can augment other modalities. Gesture commands were found to be natural, especially for commands with spatial association in design environment control.The project consist of integration of the three technologies as wireless,gesture & embedded. In robotics technology we design machines to do the specified tasks and in the advanced version of it robots are designed to be adaptive, that is, respond according to the changing environment and even autonomous, that is, capable to make decisions on their own. While designing a robot the most important thing to be taken in consideration is, obviously, the function to be performed. Robots have basic levels of complexity and each level has its scope for performing the requisite function.The levels of complexity of robots is defined by the members number of actuators and sensors used and for advanced robots the type and number of microprocessors and microcontrollers used. Each increasing component adds to the scope of functionality of a robot. With every joint added, the degrees of freedom in which a robot can work increases and with the quality of the microprocessors and microcontrollers the accuracy and effectiveness with which a robot can work is enhanced.

ContentsChapter-1: Overview of project1.1 Introduction1.2 Aim of our project1.3 Components used in the projectChapter-2: Project Technologies2.1 Embedded system2.1.1 Fields of embedded system2.1.2 Characteristics of embedded system2.1.3 Applications of embedded system2.2 Gesture technology2.2.1 Hand gesture system2.2.2 Applications of gesture technology2.3 Wireless technology2.3.1 Wireless system2.3.2 Applications of wireless technologyChapter 3-Arduino board with Atmega328 microcontroller3.1 Introduction3.2Characteristics of arduino board3.3 Board description3.4 Pin configuration of Atmega3283.5 Pin description3.6 Block diagram3.7 Programming environment with Atmega 328Chapter 4- Accelerometer (MEMs)4.1 Introduction4.2 Basic principle4.3 Structure 4.4 Types of accelerometer4.5 ADXL3354.6 Theory of operation of ADXL3354.7 Pin configuaration and description4.8 Applications of accelerometerChapter 5-RF-module5.1 Introduction 5.2 RF-Transmitter5.3 RF-Encoder (HT12E)5.3.1 Features of HT12E5.3.2 Pin description5.3.3 Applications 5.4 RF-Receiver5.5 RF-Decoder (HT12D)5.5.1 Pin description5.5.2 ApplicationsChapter 6-Mechanical Components6.1 Motors 6.2 Wheels 6.3 Types of wheels6.4 Three Wheeled robot6.5 ChassisChapter 7-Processing of robotResultConclusion Future improvementsApendixReferences

List of tables

4.1 Description of ADXL3355.1 Description of HTI2E5.2 Description of HT12D

List of figures 1.1 Basic block diagram of project1.2 Modules of project2.1 Embedded system fields2.3 Gesture movement diagram.4 Network connection in wireless system3.1 Simple arduino board3.2 Pin diagram of Atmega3283.3 Block diagram of arduino4.1 Block diagram of ADXL3354.2 pin diagram of ADXL3355.1pin diagram of RF-Encoder 5.2 pin diagram of RF-Decoder6.1 3wheeled robot

Abbreviations

RF-Radio frequencyGPS-Global positioning systemLAN-Local area networkMEMs-Micro electromechanical systemPDA-Personal digital assistantHMI-Human machine interfaceGSM-Global service for mobileCDMA-Code division multiple accessGPRS-Global packet radio serviceQCN-Quick catcher networkINS-Inertial navigation system

CHAPTER 01 OVERVIEW OF PROJECT

1.1 INTRODUCTION

Finalizing the decision of making a gesture controlled robot that will be manoeuvred by a hand gloved mounted with the transmission circuit assembly. The circuit assembly will consist of accelerometer & Arduino board along with an RF transmitter, which together function as a input device to the bot. We decided on this project because we wanted to do a basic application of controlling a vehicle with your hand. The controls of our robot are based on gesture of hand, which becomes simple for any person to handle it. The basic working principle for our robot is passage of the data signals of accelerometer readings to the Arduino board fitted on the bot. The programe compiled in that arduino runs according to that value, which make the bot function accordingly .While we have used two-axis accelerometer. In which, one axis will control the speed in forward or backward direction and other axis will control the turning mechanism. Fig no-1.1 Basic block diagram of project

1.2 AIM OF PROJECT

The purpose of our project is to control a toy car using flex sensors attached to a glove. The flex sensors are intended to replace the remote control that is generally used to run the car. Additionally we also created another mode which will allow us to use an accelerometer to control the forward and backward, and left and right movements, while using a flex sensor to control the throttle of the car. We have two gloves with one flex sensor and accelerometer, respectively attached to it. First of all, we do some experiments on accelerometers and flex sensors and try to get the required results (calibration). Then, our next task is to process the sensor data through aurdino and transmit it to bot's aurdino which thereafter, controls the motor driver of the car. For wireless communication between arduino, we think of RF module so that it becomes handy to control the car. Then we do work of the mechanical aspects of the car so that we can easily control through gesture1.3 Components used in the project

There are mainly four components used for processing &performing the action by the robot which are as follows- Arduino board with atmega328 microcontroller Micro electro mechanical device (MEMs) named as Accelerometer RF Module Mechanical components

Fig no:1.2 Modules of project

CHAPTER 02PROJECT TECHNOLOGIES

2.1 Embedded technology

Anembedded systemis acomputer systemdesigned for specific control functions within a larger system, often withreal-time computingconstraints.It is embeddedas part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as apersonal computer(PC), is designed to be flexible and to meet a wide range of end-user needs. Embedded systems control many devices in common use today. Embedded systems contain processing cores that are typically either microcontrollersordigital signal processors.The key characteristic, however, is being dedicated to handle a particular task. Since the embedded system is dedicated to specific tasks, design engineers can optimize it to reduce the size and cost of the product and increase the reliability and performance. Some embedded systems are mass-produced, benefiting fromeconomies of scale. Physically, embedded systems range from portable devices such asdigital watches andMP3 players, to large stationary installations liketraffic lights,factory controllers, or the systems controllingnuclear power plants. Complexity varies from low, with a singlemicrocontrollerchip, to very high with multiple units,peripherals and networks mounted inside a largechassisor enclosure. Embedded systems span all aspects of modern life and there are many examples of their use. Telecommunications systems employ numerous embedded systems fromtelephone switchesfor the network tomobile phonesat the end-user. Computer networking uses dedicatedroutersandnetwork bridgesto route data. Consumer electronicsincludepersonal digital assistants(PDAs),mp3 players, mobile phones,videogame consoles,digital cameras,DVD players,GPSreceivers, and printers. Many household appliances, such asmicrowave ovens,washing machines anddishwashers, are including embedded systems to provide flexibility, efficiency and features. AdvancedHVACsystems use networkedthermostatsto more accurately and efficiently control temperature that can change by time of day andseason.Home automationuses wired- and wireless-networking that can be used to control lights, climate, security, audio/visual, surveillance, etc., all of which use embedded devices for sensing and controlling.

2.1.1 Fields of Embedded System

Fig no:2.1 Embedded system fields

2.1.2 Characteristics of Embedded technology

1. Embedded systems are designed to do some specific task, rather than be a general-purpose computer for multiple tasks. Some also havereal-timeperformance constraints that must be met, for reasons such as safety and usability; others may have low or no performance requirements, allowing the system hardware to be simplified to reduce costs.

2. Embedded systems are not always standalone devices. Many embedded systems consist of small, computerized parts within a larger device that serves a more general purpose. For example, theGibson Robot Guitarfeatures an embedded system for tuning the strings, but the overall purpose of the Robot Guitar is, of course, to play music.Similarly, an embedded system in an automobileprovides a specific function as a subsystem of the car itself.

3. The program instructions written for embedded systems are referred to asfirmware, and are stored in read-only memory orFlash memorychips. They run with limited computer hardware resources: little memory, small or non-existent keyboard or screen.

2.1.3 Applications of embedded technology

2.2 Gesture Technology

Gesture recognitionis a topic incomputer scienceandlanguage technologywith the goal of interpreting humangesturesvia mathematicalalgorithms. Gestures can originate from any bodily motion or state but commonly originate from thefaceorhand. Current focuses in the field include emotion recognition from the face and hand gesture recognition. Many approaches have been made using cameras andcomputer visionalgorithms to interpretsign language. However, the identification and recognition of posture, gait,proxemics, and human behaviors is also the subject of gesture recognition techniques. Gesture recognition can be seen as a way for computers to begin to understand humanbody language, this building a richer bridge between machines and humans than primitivetext user interfacesor evenGUIs(graphical user interfaces), which still limit the majority of input to keyboard and mouse. Gesture recognition enables humans to interface with the machine (HMI) and interact naturally without any mechanical devices. Using the concept of gesture recognition, it is possible to point a finger at thecomputer screenso that the cursorwill move accordingly. This could potentially make conve0ntionalinput devicessuch asmouse,keyboardsand eventouch-screens redundant. Gesture recognition can be conducted with techniques fromcomputer visionandimage processing. The literature includes ongoing work in the computer vision field on capturing gestures or more general human pose and movements by cameras connected to a computer.In computer interfaces, two types of gestures are distinguished:We consider online gestures, which can also be regarded as direct manipulations like scaling and rotating. In contrast, offline gestures are usually processed after the interaction is finished; e. g. a circle is drawn to activate a context menu.Offline gestures: Those gestures that are processed after the user interaction with the object. An example is the gesture to activate a menu.Online gestures: Direct manipulation gestures. They are used to scale or rotate a tangible object.

2.2.1 Hand Gesture system

Fig no:2.3 Gesture movement diagram

2.2.2 Applications of Gesture technology

Gesture recognition is useful for processing information from humans which is not conveyed through speech or type. As well, there are various types of gestures which can be identified by computers. Sign language recognition. Just as speech recognition can transcribe speech to text, certain types of gesture recognition software can transcribe the symbols represented throughsign languageinto text. For socially assistive robotics. By using proper sensors (accelerometers and gyros) worn on the body of a patient and by reading the values from those sensors, robots can assist in patient rehabilitation. The best example can be stroke rehabilitation. Directional indication through pointing. Pointing has a very specific purpose in oursociety, to reference an object or location based on its position relative to ourselves. The use of gesture recognition to determine where a person is pointing is useful for identifying the context of statements or instructions. This application is of particular interest in the field ofrobotics. Control through facial gestures. Controlling a computer through facial gestures is a useful application of gesture recognition for users who may not physically be able to use a mouse or keyboard.Eye trackingin particular may be of use for controlling cursor motion or focusing on elements of a display. Alternative computer interfaces. Foregoing the traditional keyboard and mouse setup to interact with a computer, strong gesture recognition could allow users to accomplish frequent or common tasks using hand or face gestures to a camera. Immersive game technology. Gestures can be used to control interactions within video games to try and make the game player's experience more interactive or immersive. Virtual controllers. For systems where the act of finding or acquiring a physical controller could require too much time, gestures can be used as an alternative control mechanism. Controlling secondary devices in a car or controlling a television set are examples of such usage.

Affective computing. Inaffective computing, gesture recognition is used in the process of identifying emotional expression through computer systems. Remote control. Through the use of gesture recognition, "remote controlwith the wave of a hand" of various devices is possible. The signal must not only indicate the desired response, but also which device to be controlled.

2.3 Wireless TechnologyWirelesstelecommunicationsis the transfer of information between two or more points hat are not physically connected. Distances can be short, such as a few meters fortelevisionremote control, or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portabletwo-way radios,cellular telephones, personal digital assistants(PDAs), andwireless networking. Other examples ofwireless technologyincludeGPSunits,Garage door openersor garage doors, wirelesscomputer mice, keyboardsandHeadset (audio),headphones,radio receivers,satellite television,broadcast televisionand cordlesstelephones. Wireless operationspermit services, such as long range communications, that are impossible or impractical to implement with the use of wires. The term is commonly used in the telecommunications industry to refer to telecommunications systems (e.g. radio transmitters and receivers, remote controls, computer networks, network terminals, etc.) which use some form of energy (e.g.radio frequency(RF),acoustic energy, etc.) to transfer information without the use of wires.Information is transferred in this manner over both short and long distances. Wireless networking(i.e. the various types of unlicensed 2.4GHz WiFi devices) is used to meet many needs. Perhaps the most common use is to connect laptop users who travel from location to location. Another common use is for mobile networks that connect via satellite. A wireless transmission method is a logical choice to network a LAN segment that must frequently change locationsThe following situations justify the use of wireless technology: To span a distance beyond the capabilities of typical cabling, To provide a backup communications link in case of normal network failure, To link portable or temporary workstations, To overcome situations where normal cabling is difficult or financially impractical, or To remotely connect mobile users or networks.

2.3.1 Wireless System

Fig no:2.4 Network connection in wireless system

2.3.2 Applications of wireless technologyBusinesses succeed today because they are fast, not vast. Instead of holding large stockpiles of materials and finished goods inventory to meet customer commitments, companies rely on fast information exchange to drive responsive enterprise and supply chain systems that adjust to dynamic production, distribution and service needs.If information is old, it's wrong. And when information is wrong, systems stop, shipments are delayed, and service and productivity suffer. Wireless technology has become essential for getting accurate, real-time information when and where its needed.Now companies are finding new ways to use wireless to create a competitive advantage. Theyre leveraging legacy wireless LANs to provide automated asset tracking and to connect their workforces with wireless voice-over-IP (VoIP). Real-time responsiveness is being extended beyond the four walls with GPS and wide-area voice & data networks for dynamic dispatch and remote access to enterprise information. Before starting a wireless project, make sure your solutions provider is grounded in all the aspects required to make a system successful. Many providers can hang access points and install radio cards, but cant make the connection between wireless technology and business value.

Mobile telephonesOne of the best-known examples of wireless technology is themobile phone, also known as a cellular phone, with more than 4.6 billion mobile cellular subscriptions worldwide as of the end of 2010.]These wireless phones use radio waves to enable their users to make phone calls from many locations worldwide. They can be used within range of themobile telephone siteused to house the equipment required to transmit and receive theradio signalsfrom these instruments.

Wireless data communicationsWireless data communications are an essential component of mobile computing.The various available technologies differ in local availability, coverage range and performance,and in some circumstances, users must be able to employ multiple connection types and switch between them. To simplify the experience for the user, connection manager software can be used,or amobile VPNdeployed to handle the multiple connections as a secure, singlevirtual network.Supporting technologies include

Wi-FiIt is a wirelesslocal area networkthat enables portable computing devices to connect easily to theInternet.Standardized asIEEE 802.11a,b,g,n,Wi-Fiapproaches speeds of some types of wiredEthernet. Wi-Fi has become the de facto standard for access in private homes, within offices, and at public hotspots. Some businesses charge customers a monthly fee for service, while others have begun offering it for free in an effort to increase the sales of their goods.

Cellular data service It offers coverage within a range of 10-15 miles from the nearestcell site.Speeds have increased as technologies have evolved, from earlier technologies such asGSM,CDMAandGPRS, to3Gnetworks such asW-CDMA,EDGEorCDMA2000. Mobile Satellite Communicationsmay be used where other wireless connections are unavailable, such as in largely rural areasor remote locations.Satellite communicationsare especially important fortransportation,aviation,maritimeandmilitaryuse.

Wireless energy transferWireless energy transfer is a process whereby electrical energy is transmitted from a power source to an electrical load that does not have a built-in power source, without the use of interconnecting wires.

Computer interface devicesAnswering the call of customers frustrated with cord clutter, many manufactures of computer peripherals turned to wireless technology to satisfy their consumer base. Originally these units used bulky, highly limited transceivers to mediate between a computer and a keyboard and mouse, however more recent generations have used small, high quality devices, some even incorporatingBluetooth. These systems have become so ubiquitous that some users have begun complaining about a lack of wired peripherals.Wireless devices tend to have a slightly slower response time than their wired counterparts, however the gap is decreasing. Concerns about the security of wireless keyboards arose at the end of 2007, when it was revealed that Microsoft's implementation of encryption in some of its 27MHz models was highly insecure.

Wireless Printing Print barcode labels on demand wherever they are needed. Because wireless printers are independent of cabling and a wired network infrastructure, they can be used virtually anywhere and relocated in minuteswithout incurring additional costs. Wireless printing provides the responsiveness and flexibility that modern manufacturing and supply chain operations demand. These benefits come without performance trade-offs or a premium price. In fact, the total cost of ownership for wireless printing systems can be lower than traditional, wired-network configurations

CHAPTER 03ARDUINO BOARD WITH ATMEGA 328 MICROCONTROLLER

3.1 Introduction of arduino boardArduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments. Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The microcontroller on the board is programmed using theArduino programming language(based onWiring) and the Arduino development environment (based onProcessing). Arduino projects can be stand-alone or they can communicate with software running on a computer (e.g. Flash, Processing,and MaxMSP. It is a tool for making computers that can sense and control more of the physical world than your desktop computer. It's an open-source physical computing platform based on a simple microcontroller board, and a development environment for writing software for the board. Arduino can be used to develop interactive objects, taking inputs from a variety of switches or sensors, and controlling a variety of lights, motors, and other physical outputs. Arduino projects can be stand-alone, or they can be communicated with software running on your computer (e.g. Flash, Processing,MaxMSP.) The boards can be assembled by hand or purchased preassembled; the open-source IDE can be downloaded for free. The Arduino programming language is an implementation of Wiring, a similar physical computing platform, which is based on the Processing multimedia programming environment.3.2 Characteristics of arduino board

a) InexpensiveArduino boards are relatively inexpensive compared to other microcontroller platforms. The least expensive version of the Arduino module can be assembled by hand, and even the pre-assembled Arduino modules cost less than $50b) Cross-platform The Arduino software runs on Windows, Macintosh OSX, and Linux operating systems. Most microcontroller systems are limited to Windows.c) Simple, clear programming environment The Arduino programming environment is easy-to-use for beginners, yet flexible enough for advanced users to take advantage of as well. For teachers, it's conveniently based on the Processing programming environment, so students learning to program in that environment will be familiar with the look and feel of Arduinod) Open source and extensible softwareThe Arduino software and is published as open source tools, available for extension by experienced programmers. The language can be expanded through C++ libraries, and people wanting to understand the technical details can make the leap from Arduino to the AVR C programming language on which it's based.SImilarly, you can add AVR-C code directly into your Arduino programs if you want to.e) Open source and extensible hardwareThe Arduino is based on Atmel'sATMEGA8andATMEGA168microcontrollers. The plans for the modules are published under a Creative Commons license, so experienced circuit designers can make their own version of the module, extending it and improving it.

Fig no:3.1 Simple arduino board3.3 Board description`The Arduino Uno is a microcontroller board based on theATmega328. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16MHzcrystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. "Uno" means one in Italian and is named to mark the upcoming release of Arduino 1.0.

3.4 Pin configuration of ATmega 328

Fig no:3.2 Pin diagram of Atmega328

3.5 Pin Descriptions

VCC Digital supply voltage

GND Ground

Port B (PB7) Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port B output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset condition becomes active, even if the clock is not running. Depending on the clock selection fuse settings, PB7 can be used as output from the inverting Oscillator amplifier.

PB6 Depending on the clock selection fuse settings, PB6 can be used as input to the inverting Oscillator amplifier and input to the internal clock operating circuit.

Port C (PC5) Port C is a 7-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up resistors are activated. The Port C pins are tri-stated when a reset condition becomes active, even if the clock is not running.

PC6 PC6 is used as an I/O pin. Note that the electrical characteristics of PC6 differ from those of the other pins of Port C.; PC6 is used as a Reset input. A low level on this pin for longer than the minimum pulse length will generate a Reset, even if the clock is not running.

Port D (PD7) Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port D output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset condition becomes active, even if the clock is not running.

AVcc AVCC is the supply voltage pin for the A/D Converter. It should be externally connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to VCC through a low-pass filter. Note that PC6...4 use digital supply voltage.

AREF AREF is the analog reference pin for the A/D Converter.

3.6 Block Diagram

Fig no:3.3 block diagram of arduino

3.7 Programming Environment of ATmega 328

Arduino programs can be divided in three main parts:structure,values(variables and constants), andfunctions3.7.1 StructureSetup ( ) The setup () function is called when a sketch starts. Use it to initialize variables, pin modes, start using libraries, etc. The setup function will only run once, after each powerup or reset of the Arduino boaLoop ()After creating a setup () function, which initializes and sets the initial values, the loop() function does precisely what its name suggests, and loops consecutively, allowing your program to change and respond. Use it to actively control the Arduino board.

3.7.2 Constants Constants are predefined variables in the Arduino language. They are used to make the programs easier to read. We classify constants in groups.

High The meaning of high is somewhat different depending on whether a pin is set to an input or output When a pin is configured as an with pinMode, and read with digitalRead, the microcontroller will report high if a voltage of 3 volts or more is present at the pin.LowThe meaning of low also has a different meaning depending on whether a pin is set to input or output. When a pin is configured as an input with pin mode, and read with digital read, the microcontroller will report low if a voltage of 2 volts or less is present at the pin.

3.7.3 Functions

Digital I/O There are basically three functions are used in digital i/o.

Pin Mode() Configures the specified pin to behave either as an input or an output.Digital Write () Write a high or a lowvalue to a digital pin. If the pin is configured as an iput, writing a high value with digital Write () will enable an internal 20K pull-up resistor. Writing low will disable the pull-up. The pull-up resistor is enough to light an led dimly, so ifLEDsappear to work, but very dimly, this is a likely cause. The remedy is to set the pin to an output with the pin Mode () function.

Digital Read () Reads the value from a specified digital pin, eitherhighorlow.

Analog I/O In analog i/o there are also three functions to take input from accelerometer which are

Analog Reference () Configures the reference voltage used for analog input (i.e. the value used as the top of the input range). The options are:

Default The default analog reference of 5 volts (on 5V Arduino boards) or 3.3 volts (on 3.3V Arduino boards)

Internal An built-in reference, equal to 1.1 volts on theATmega168orATmega328and 2.56 volts on theATmega8(not available on the Arduino Mega)

Internal 1V1 A built-in 1.1V reference (Arduino Mega only)

Internal 2V56 A built-in 2.56V reference (Arduino Mega only)

External The voltage applied to the AREF pin (0 to 5V only) is used as the reference.

CHAPTER 04ACCELEROMETER (MEMs)

4.1 Introduction

Anaccelerometeris a device that measuresproper acceleration, also called thefour-acceleration. For example, an accelerometer on a rocket accelerating through space will measure the rate of change of the velocity of the rocket relative to anyinertial frame of reference. However, theproper accelerationmeasured by an accelerometer isnot necessarilythe coordinate acceleration (rate of change of velocity). Instead, it is the acceleration associated with the phenomenon of weight experienced by any test mass at rest in theframe of referenceof the accelerometer device. For an example where these types of acceleration differ, an accelerometer will measure a value ofgin the upward direction when remaining stationary on the ground, because masses on earth have weight m*g. By contrast, an accelerometer in gravitationalfree falltoward the center of the Earth will measure a value of zero because, even though its speed is increasing, it is at rest in aframe of referencein which objects areweightless.An accelerometer thus measuresweight per unit of (test) mass, a quantity of with dimensions of acceleration that is sometimes known asspecific force, org-force(although it is not a force). Another way of stating this is that by measuring weight, an accelerometer measures the acceleration of the free-fall reference frame (inertial reference frame) relative to itself (the accelerometer). This measurable acceleration is not the ordinary acceleration of Newton (in three dimensions), but ratherfour-acceleration, which is acceleration away from ageodesicpath in four-dimensional space-time.Most accelerometers do not display the value they measure, but supply it to other devices. Real accelerometers also have practical limitations in how quickly they respond tochanges in acceleration, and cannot respond to changes above a certain frequency of change.Single- and multi-axis models of accelerometer are available to detect magnitude and direction of the proper acceleration (org-force), as avectorquantity, and can be used to sense orientation (because direction of weight changes), coordinate acceleration (so long as it produces g-force or a change in g-force), vibration,shock, and falling (a case where the proper acceleration changes, since it tends toward zero).Micromachinedaccelerometers are increasingly present in portable electronic devices and video game controllers, to detect the position of the device or provide for game input.Pairs of accelerometers extended over a region of space can be used to detect differences (gradients) in the proper accelerations offrames of referencesassociated with those points.

4.2 Basic Principle An accelerometer measuresproper acceleration, which is the acceleration it experiences relative to freefall and is the acceleration felt by people and objects. Put another way, at any point in spacetime theequivalence principleguarantees the existence of a localinertial frame, and an accelerometer measures the acceleration relative to that frame.Such accelerations are popularly measured in terms ofg-force. An accelerometer at rest relative to the Earth's surface will indicate approximately 1 gupwards, because any point on the Earth's surface is accelerating upwards relative to the local inertial frame (the frame of a freely falling object near the surface). To obtain the acceleration due to motion with respect to the Earth, this "gravity offset" must be subtracted and corrections for effects caused by the Earth's rotation relative to the inertial frame. The reason for the appearance of a gravitational offset isEinstein's equivalence principle, which states that the effects of gravity on an object are indistinguishable from acceleration. When held fixed in a gravitational field by, for example, applying a ground reaction force or an equivalent upward thrust, the reference frame for an accelerometer (its own casing) accelerates upwards with respect to a free-falling reference frame. The effects of this acceleration are indistinguishable from any other acceleration experienced by the instrument, so that an accelerometer cannot detect the difference between sitting in a rocket on the launch pad, and being in the same rocket in deep space while it uses its engines to accelerate at 1 g. For similar reasons, an accelerometer will readzeroduring any type offree fall. This includes use in a coasting spaceship in deep space far from any mass, a spaceship orbiting the Earth, an airplane in a parabolic "zero-g" arc, or any free-fall in vacuum. Another example is free-fall at a sufficiently high altitude that atmospheric effects can be neglected. However this does not include a (non-free) fall in which air resistance produces drag forces that reduce the acceleration, until constant terminal velocityis reached. At terminal velocity the accelerometer will indicate 1 g acceleration upwards. For the same reason a sky diver, upon reaching terminal velocity, does not feel as though he or she were in "free-fall", but rather experiences a feeling similar to being supported (at 1 g) on a "bed" of uprushing air. Acceleration is quantified in theSIunitmetres per second per second(m/s2), in thecgsunitgal(Gal), or popularly in terms ofg-force(g).For the practical purpose of finding the acceleration of objects with respect to the Earth, such as for use in aninertial navigation system, a knowledge of local gravity is required. This can be obtained either by calibrating the device at rest, or from a known model of gravity at the approximate current position.

4.3 Structure of AccelerometerConceptually, an accelerometer behaves as a damped mass on a spring. When the accelerometer experiences an acceleration, the mass is displaced to the point that the spring is able to accelerate the mass at the same rate as the casing. The displacement is then measured to give the acceleration.In commercial devices,piezoelectric,piezoresistiveandcapacitivecomponents are commonly used to convert the mechanical motion into an electrical signal. Piezoelectric accelerometers rely on piezoceramics (e.g.lead zirconate titanate) or single crystals (e.g.quartz, tourmaline). They are unmatched in terms of their upper frequency range, low packaged weight and high temperature range. Piezoresistive accelerometers are preferred in high shock applications. Capacitive accelerometers typically use a silicon micro-machined sensing element. Their performance is superior in the low frequency range and they can be operated inservomode to achieve high stability and linearity. Modern accelerometers are often smallmicro electro-mechanical systems(MEMS), and are indeed the simplest MEMS devices possible, consisting of little more than acantilever beamwith a proof mass (also known as seismic mass). Damping results from the residual gas sealed in the device. As long as theQ-factoris not too low, damping does not result in a lower sensitivity. Under the influence of external accelerations the proof mass deflects from its neutral position. This deflection is measured in an analog or digital manner. Most commonly, the capacitance between a set of fixed beams and a set of beams attached to the proof mass is measured. This method is simple, reliable, and inexpensive. Integratingpiezoresistorsin the springs to detect spring deformation, and thus deflection, is a good alternative, although a few more process steps are needed during the fabrication sequence. For very high sensitivitiesquantum tunnelingis also used; this requires a dedicated process making it very expensive. Optical measurement has been demonstrated on laboratory scale. Another, far less common, type of MEMS-based accelerometer contains a small heater at the bottom of a very small dome, which heats the air inside the dome to cause it to rise. A thermocouple on the dome determines where the heated air reaches the dome and the deflection off the center is a measure of the acceleration applied to the sensor.Most micromechanical accelerometers operatein-plane, that is, they are designed to be sensitive only to a direction in the plane of the die. By integrating two devices perpendicularly on a single die a two-axis accelerometer can be made. By adding an additionalout-of-planedevice three axes can be measured. Such a combination may have much lower misalignment error than three discrete models combined after packaging. Micromechanical accelerometers are available in a wide variety of measuring ranges, reaching up to thousands ofg's. The designer must make a compromise between sensitivity and the maximum acceleration that can be measured.

4.4 Types of Accelerometer Bulk micromachined capacitive Bulk micromachined piezoelectric resistive Capacitive spring mass base DC response Electromechanicalservo(Servo Force Balance) High gravity High temperature Laser accelerometer Low frequency Magnetic induction Modally tuned impact hammers Null-balance Optical Pendulous integrating gyroscopic accelerometer Piezoelectric accelerometer Resonance Seat pad accelerometers

04.5 ADXL335 Accelerometer

This is the latest in a long, proven line of analog sensors - the holy grail of accelerometers. The ADXL335 is a triple axis accelerometer with extremely low noise and power consumption - only 320uA! The sensor has a full sensing range of +/-3g.There is no on-board regulation, provided power should be between 1.8 and 3.6VDC. The ADXL335 is a small, thin, low power, complete 3-axis accelerometer with signal conditioned voltage outputs. The product measures acceleration with a minimum full-scale range of 3 g. It can measure the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion, shock, or vibration. The user selects the bandwidth of the accelerometer using the CX, CY, and CZ capacitors at the XOUT, YOUT, and ZOUT pins. Bandwidths can be selected to suit the application, with a range of 0.5 Hz to 1600 Hz for the X and Y axes, and a range of 0.5 Hz to 550 Hz for the Z axis. The ADXL335 is available in a small, low profile, 4 mm 4 mm 1.45 mm, 16-lead, plastic lead frame chip scale package (LFCSP_LQ).

4.6 Theory of operation of adxl335The ADXL335 is a complete 3-axis acceleration measurement system. The ADXL335 has a measurement range of 3 g mini-mum. It contains a poly silicon surface-micro machined sensor and signal conditioning circuitry to implement open-loop acceleration measurement architecture. The output signals are analog voltages that are proportional to acceleration. The accelerometer can measure the static acceleration of gravity in tilt-sensing applications as well as dynamic acceleration resulting from motion, shock, or vibration. The sensor is a polysilicon surface-micromachined structure built on top of a silicon wafer. Polysilicon springs suspend the structure over the surface of the wafer and provide a resistance against acceleration forces. Deflection of the structure is meas-ured using a differential capacitor that consists of independent fixed plates and plates attached to the moving mass. The fixed plates are driven by 180 out-of-phase square waves. Acceleration deflects the moving mass and unbalances the differential capacitor resulting in a sensor output whose amplitude is proportional to acceleration. Phase-sensitive demodulation techniques are then used to determine the magnitude and direction of the acceleration. Fig no:4.1 Block diagram of ADXL335The demodulator output is amplified and brought off-chip through a 32 k resistor. The user then sets the signal bandwidth of the device by adding a capacitor. This filtering improves measurement resolution and helps prevent aliasing.

4.7 Pin Configuration of ADXL335

Fig no:4.2 pin diagram of ADXL335 Pin description1 NC No Connect.1

2 ST Self-Test.

3 COM Common.

4 NC No Connect.1

5 COM Common.

6 COM Common.

7 COM Common.

8 ZOUT Z Channel Output.

9 NC No Connect.1

10 YOUT Y Channel Output.

11 NC No Connect. 1

12 XOUT X Channel Output.

13 NC No Connect. 1

14 VS Supply Voltage (1.8 V to 3.6 V).

15 VS Supply Voltage (1.8 V to 3.6 V).

16 NC No Connect. 1

EP Exposed Pad Not internally connected. Solder for mechanical integrity.

Table no 4.1:Description of ADXL335

4.8 Applications of Accelerometer EngineeringAccelerometers can be used to measure vehicle acceleration. They allow for performance evaluation of both the engine/drive train and thebraking systems.Accelerometers can be used to measurevibrationon cars, machines, buildings, process control systems and safety installations. They can also be used to measure seismic activity, inclination, machine vibration, dynamic distance and speed with or without the influence of gravity. Applications for accelerometers that measure gravity, wherein an accelerometer is specifically configured for use ingravimetry, are calledgravimeters. Notebook computers equipped with accelerometers can contribute to theQuake-Catcher Network(QCN), aBOINC projectaimed at scientific research of earthquakes.

BiologyAccelerometers are also increasingly used in the biological sciences. High frequency recordings of bi-axialor tri-axial acceleration (>10Hz) allows the discrimination of behavioral patterns while animals are out of sight. Furthermore, recordings of acceleration allow researchers to quantify the rate at which an animal is expending energy in the wild, by either determination of limb-stroke frequencyor measures such as overall dynamic body accelerationSuch approaches have mostly been adopted by marine scientists due to an inability to study animals in the wild using visual observations, however an increasing number of terrestrial biologists are adopting similar approaches. This device can be connected to an amplifier to amplify the signal.

IndustryCondition monitoringAccelerometers are also used for machinery health monitoring to report the vibration and its changes in time of shafts at the bearings of rotating equipment such as turbines,pumps,fans, rollers, compressors,andcooling towers. Vibration monitoring programs are proven to warn of impending failure, save money, reduce downtime, and improve safety in plants worldwide by detecting conditions such as wear and tear of bearings, shaft misalignment, rotor imbalance, gear failureor bearing faultwhich, if not attended to promptly, can lead to costly repairs. Accelerometer vibration data allows the user to monitor machines and detect these faults before the rotating equipment fails completely. Vibration monitoring programs are utilized in industries such as automotive manufacturing,machine tool applications,pharmaceutical production,power generationand power plants,pulp and paper,sugar mills, food and beverage production, water and wastewater, hydropower, petrochemical and steel manufacturing.

Building and structural monitoringAccelerometers are used to measure the motion and vibration of a structure that is exposed to dynamic loads. Measuring and recording how a structure responds to these inputs is critical for assessing the safety and viability of a structure. This type of monitoring is called Dynamic Monitoring.

Medical applicationsZoll'sAEDPlus uses CPR-Dpadz which contains an accelerometer to measure the depth of CPR chest compressions. Within the last several years,Nike,Polarand other companies have produced and marketed sports watches for runners that includefootpods, containing accelerometers to help determine the speed and distance for the runner wearing the unit.In Belgium, accelerometer-based step counters are promoted by the government to encourage people to walk a few thousand steps each day.Herman Digital Trainer uses accelerometers to measure strike force in physical training.

NavigationInertial navigation systemAnInertial Navigation System(INS) is anavigationaid that uses a computer and motion sensors (accelerometers) to continuously calculate viadead reckoningthe position, orientation, andvelocity(direction and speed of movement) of a moving object without the need for external references. Other terms used to refer to inertial navigation systems or closely related devices includeinertial guidance system,inertial reference platform, and many other variations.An accelerometer alone is unsuitable to determine changes in altitude over distances where the vertical decrease of gravity is significant, such as for aircraft and rockets. In the presence of a gravitational gradient, the calibration and data reduction process is numerically unstable.

TransportAccelerometers are also being used in Intelligent Compaction rollers. Accelerometers are used alongsidegyroscopesininertial guidancesystems. One of the most common uses forMEMSaccelerometers is inairbagdeployment systems for modern automobiles. In this case the accelerometers are used to detect the rapid negative acceleration of the vehicle to determine when a collision has occurred and the severity of the collision. Another common automotive use is inelectronic stability controlsystems, which use a lateral accelerometer to measure cornering forces. The widespread use of accelerometers in the automotive industry haspushed their cost downdramatically.Another automotive application is the monitoring ofnoise, vibration and harshness(NVH), conditions that cause discomfort for drivers and passengers and may also be indicators of mechanical faults.Tilting trainsuse accelerometers and gyroscopes to calculate the required tilt.

VulcanologyModern electronic accelerometers are used in remote sensing devices intended for the monitoring of activevolcanosto detect the motion ofmagma.

Consumers ElectronicsAccelerometers are increasingly being incorporated into personal electronic devices.

Motion inputSomesmartphones, digital audio players andpersonal digital assistantscontain accelerometers for user interface control; often the accelerometer is used to presentlandscape or portrait viewsof the device's screen, based on the way the device is being held.Automatic Collision Notification(ACN) systems also use accelerometers in a system to call for help in event of a vehicle crash. Prominent ACN systems includeOnstarAACN service,Ford Link's 911 Assist,Toyota's Safety Connect,Lexus Link, orBMW Assist. Many accelerometer-equipped smartphones also have ACN software available for download. ACN systems are activated by detecting crash-strength G-forces.Nintendo'sWiivideo game console uses a controller called aWii Remotethat contains a three-axis accelerometer and was designed primarily for motion input. Users also have the option of buying an additional motion-sensitive attachment, theNun chuk, so that motion input could be recorded from both of the user's hands independently. Is also used on the Nintendo 3DSsystem.The SonyPlayStation 3uses theDual Shock 3remote which uses a three axis accelerometer that can be used to make steering more realistic in racing games, such as MotorstormandBurnout Paradise. TheNokia 5500sport features a 3D accelerometer that can be accessed from software. It is used for step recognition (counting) in a sport application, and for tap gesture recognition in the user interface. Tap gestures can be used for controlling the music player and the sport application, for example to change to next song by tapping through clothing when the device is in a pocket. Other uses for accelerometer inNokiaphones includePedometer functionality inNokia Sports Tracker. Some other devices provide the tilt sensing feature with a cheaper component, which is not a true accelerometer. Sleep phasealarm clocksuse accelerometric sensors to detect movement of a sleeper, so that it can wake the person when he/she is not in REM phase, therefore awakes more easily.

Orientation sensingA number of 21st century devices use accelerometers to align the screen depending on the direction the device is held, for example switching between portrait andlandscape modes. Such devices include manytablet PCsand somesmartphonesanddigital cameras. For example, Apple uses an LIS302DL accelerometer in theiPhone,iPod Touchand the 4th and 5th generationiPod Nanoallowing the device to know when it is tilted on its side. Third-party developers have expanded its use with fanciful applications such as electronicbobbleheads.TheBlackBerry Stormphone was also an early user of this orientation sensing feature. TheNokia N95andNokia N82have accelerometers embedded inside them. It was primarily used as a tilt sensor for tagging the orientation to photos taken with the built-in camera and later became available to other applications through a firmware update.As of January 2009, almost all new mobile phones and digital cameras contain at least atilt sensorand sometimes an accelerometer for the purpose of auto image rotation, motion-sensitive mini-games, and to correct shake when taking photographs. Image stabilizationCamcorders use accelerometers forimage stabilization. Still cameras use accelerometers for anti-blur capturing. The camera holds off snapping the CCD "shutter" when the camera is moving. When the camera is still (if only for a millisecond, as could be the case for vibration), the CCD is "snapped". An example application which has used such technology is the Glogger VS2,a phone application which runs onSymbian OSbased phone with accelerometer such asNokia N96. Some digital cameras, contain accelerometers to determine the orientation of the photo being taken and also for rotating the current picture when viewing.

Device integrityMany laptops feature an accelerometer which is used to detect drops. If a drop is detected, the heads of thehard diskare parked to avoid data loss and possible head or disk damage by the ensuingshock.

GravimetryAgravimeteror gravitometer, is an instrument used ingravimetryfor measuring the localgravitational field. A gravimeter is a type of accelerometer, except that accelerometers are susceptible to allvibrationsincludingnoise, that cause oscillatory accelerations. This is counteracted in the gravimeter by integral vibration isolation andsignal processing. Though the essential principle of design is the same as in accelerometers, gravimeters are typically designed to be much more sensitive than accelerometers in order to measure very tiny changes within theEarth'sgravity, of 1g. In contrast, other accelerometers are often designed to measure 1000gor more, and many perform multi-axial measurements. The constraints ontemporal resolutionare usually less for gravimeters, so that resolution can be increased by processing the output with a longer "time constant"CHAPTER 05RF-MODULE (RF TRANSMITTER & RECEIVER)

5.1 IntroductionAnRF Moduleis a (usually) small electronic circuit used to transmit, receive, or transceive radio waves on one of a number of carrier frequencies. RF Modules are widely used in consumer application such as garage door openers, wireless alarm systems, industrial remote controls, smart sensor applications, and wireless home automation systems. They are often used instead ofinfrared remote controlsas they have the advantage of not requiring line-of-sight operation. Several carrier frequencies are commonly used in commercially-available RF modules, including 433.92MHz, 315MHz, 868MHz and 915MHz. The RF module, as the name suggests, operates at Radio Frequency. The corresponding frequency range varies between 30 kHz & 300 GHz. In this RF system, the digital data is represented as variations in the amplitude of carrier wave. This kind of modulation is known as Amplitude Shift Keying (ASK).Transmission through RF is better than IR (infrared) because of many reasons. Firstly, signals through RF can travel through larger distances making it suitable for long range applications. Also, while IR mostly operates in line-of-sight mode, RF signals can travel even when there is an obstruction between transmitter & receiver. Next, RF transmission is more strong and reliable than IR transmission. RF communication uses a specific frequency unlike IR signals which are affected by other IR emitting sources. ThisRF modulecomprises of anRF Transmitterand anRF Receiver. The transmitter/receiver (Tx/Rx) pair operates at a frequency of434 MHz. An RF transmitter receives serial data and transmits it wirelessly through RF through its antenna connected at pin4. The transmission occurs at the rate of 1Kbps - 10Kbps.The transmitted data is received by an RF receiver operating at the same frequency as that of the transmitter. The RF module is often used along with a pair of encoder/decoder. The encoder is used for encoding parallel data for transmission feed while reception is decoded by a decoder.HT12E-HT12D, HT640-HT648, etc. are some commonly used encoder/decoder pair ICs.5.2 RF-TransmitterRadio transmitter designis a complex topic which can be broken down into a series of smaller topics. Aradio communication systemrequires twotuned circuitseach at the transmitterandreceiver, all four tuned to the samefrequency.The transmitter is anelectronicdevicewhich, usually with the aid of anantenna, propagates an electromagneticsignalsuch asradio,television, or othertelecommunications. Arrangement of RF-Transmitter The transmitting system consists of two tuned circuits such that the one containing the spark-gap is a persistent oscillator; the other, containing the aerial structure, is a free radiator maintained in oscillation by being coupled to the first (Nikola TeslaandGuglielmo Marconi). The oscillating system, including the aerial structure with its associated inductance-coils and condensers, is designed to be both a sufficiently persistent oscillator and a sufficiently active radiator (Oliver Lodge). The transmitting system consists of two electrically coupled circuits, one of which, containing the air-gap, is a powerful but not persistent oscillator, being provided with a device for quenching the spark so soon as it has imparted sufficient energy to the other circuit containing the aerial structure, this second circuit then independently radiating the train of slightly damped waves at its own period (Oliver Joseph Lodge andWilhelm Wien).5.3 RF-Encoder (HT12E)

The HT12E encoder is designed for remote control system applications. It will interface to RF transmitter modules to create a secure single or multiple channel RF remote control transmitter. The oscillator is configured simply with the addition of a resistor. It is capable of encoding information which consists of N address bits and 12-N data bits. Each address/data input can be set to one of the two logic states. The programmed addresses/data are transmitted together with the header bits via an RF transmission medium upon receipt of a trigger signal. HT12Eis anencoder integrated circuitof 212series of encoders. They are paired with 212series of decoders for use in remote control system applications. It is mainly used in interfacing RF and infrared circuits. The chosen pair of encoder/decoder should have same number of addresses and data format. Simply put, HT12E converts the parallel inputs into serial output. It encodes the 12 bit parallel data into serial for transmission through an RF transmitter. These 12 bits are divided into 8 address bits and 4 data bits.HT12E has a transmission enable pin which is active low. When a trigger signal is received on TE pin, the programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium. HT12E begins a 4-word transmission cycle upon receipt of a transmission enable. This cycle is repeated as long as TE is kept low. As soon as TE returns to high, the encoder output completes its final cycle and then stops.

5.3.1 Features of HT12E Operating voltage: 2.4V~12V Low power and high noise immunity CMOS technology Low standby current: 0.1uA (typ.) at VDD=5V Built-in oscillator, needs only 5% resistor Compatible with the HT12D decoder IC 18-pin DIP

Fig no:5.1 pin diagram of RF-Encoder5.3.2 Pin DescriptionPin NoFunctionName

18 bit Address pins for inputA0

2A1

3A2

4A3

5A4

6A5

7A6

8A7

9Ground (0V)Ground

104 bit Data/Address pins for inputAD0

11AD1

12AD2

13AD3

14Transmission enable; active lowTE

15Oscillator inputOsc2

16Oscillator outputOsc1

17Serial data outputOutput

18Supply voltage; 5V (2.4V-12V)Vcc

Table 5.1 Description of HTI2E 5.3.3 Application of HT12E Burglar alarm system Smoke and fire alarm system Garage door controllers Car door controllers Car alarm system Security system Cordless telephones5.4 RF-Receiver The RF receiver is specially degined to receive the signal from the rf transmitter to demodulate or decode the original signal.for receiving we use receiver and for decoding we use the IC HT12D.The description of HT12D are as under as follows-5.5 RF-Decoder (HT12D)

HT12Dis adecoder integrated circuitthat belongs to 212series of decoders. This series of decoders are mainly used for remote control system applications, like burglar alarm, car door controller, security system etc. It is mainly provided to interface RF and infrared circuits.They are paired with 212series of encoders. The chosen pair of encoder/decoder should have same number of addresses and data format. In simple terms, HT12D converts the serial input into parallel outputs. It decodes the serial addresses and data received by, say, an RF receiver, into parallel data and sends them to output data pins. The serial input data is compared with the local addresses three times continuously. The input data code is decoded when no error or unmatched codes are found. A valid transmission in indicated by a high signal at VT pin.HT12D is capable of decoding 12 bits, of which 8 are address bits and 4 are data bits. The data on 4 bit latch type output pins remain unchanged until new is received. The decoders receive serial addresses and data from a programmed 212series of encoders that are transmitted by a carrier using an RF or an IR transmission medium. They compare the serial input data three times continuously with their local addresses. If no error or unmatched codes are found, the input data codes are decoded and then transferred to the output pins. The VT pin also goes high to indicate a valid transmission. The 212series of decoders are capable of decoding informations that consist of N bits of address and 12-N bits of data. Of this series, the HT12D is arranged to provide 8 address bits and 4 data bits, and HT12F is used to decode 12 bits of address information.

Pin Configuration

Fig no:5.2 pin diagram of RF-Decoder

5.5.1 Pin DescriptionPin NoFunctionName

18 bit Address pins for inputA0

2A1

3A2

4A3

5A4

6A5

7A6

8A7

9Ground (0V)Ground

104 bit Data/Address pins for outputD0

11D1

12D2

13D3

14Serial data inputInput

15Oscillator outputOsc2

16Oscillator inputOsc1

17Valid transmission; active highVT

18Supply voltage; 5V (2.4V-12V)Vcc

Table 5.2 description of HT12D

5.5.2 ApplicationRF Modules are used in applications where size, price and power consumption coupled with long range are important parameters. RF Module integration with MCU, memory and ADC, will fit almost all applications.

Industrial AutomationIn Industrial automation there is an ever-increasing need to monitor and analyse the status or wear and tear of machines and sensors. Using the low power wireless connectivity of the RF Module is a low high reliability method of getting access to this data.

Remote Meter ReadingWith the extremely high integration of the RF Module, its high output power and sensitivity can be used to make a single chip long range solutions for remote meter reading.

SecurityFrequency hopping and short time on air increases security in applications using the RF module. In Remote Keyless Entry systems the low voltage operation, internal voltage regulator and low current operation of the RF Module increases the battery life time.

CHAPTER 06MECHANICAL COMPONENTS

6.1 IntroductionWhen I first started building my first robot, someone much more experienced than me once said paraphrased, "if you build a mechanically crappy robot with expert programming and control, you will only get a crappy robot; build a mechanically professional robot with crappy programming and control, you will still get a well built robot." Its very good advice which I still use today.Planning. Would you say someone who plans his future will have a better future? YES! I cannot emphasize any more for you to design your robot out on paper (or computer) first. This means plan out everything, such as whatmaterial to build your robot out of 360){// yAxis = (sensorValuey-418); digitalWrite(motor1, HIGH); digitalWrite(motor2, LOW); digitalWrite(motor3, HIGH); digitalWrite(motor4, LOW);/* analogWrite(ledPin2, yAxis*1.77); digitalWrite(ledPin1, LOW);*/}if (sensorValuex < 310){// xAxis = (330-sensorValuex); digitalWrite(motor1, HIGH); digitalWrite(motor2, LOW); digitalWrite(motor3, HIGH); digitalWrite(motor4, HIGH);/* analogWrite(ledPin1, xAxis*1.75); digitalWrite(ledPin2, LOW);*/}if (sensorValuex > 360){// xAxis = (sensorValuex-373); digitalWrite(motor1, HIGH); digitalWrite(motor2, HIGH); digitalWrite(motor3, HIGH); digitalWrite(motor4, LOW);/* analogWrite(ledPin2, xAxis*1.75); digitalWrite(ledPin1, LOW);*/}

References1. ^Michael Barr."Embedded Systems Glossary".Neutrino Technical Library. Retrieved 2007-04-21.2. ^Heath, Steve (2003).Embedded systems design. EDN series for design engineers (2 ed.). Newnes. p.2.ISBN978-0-7506-5546-0. "An embedded system is amicroprocessorbased system that is built to control a function or a range of functions."3. ^Michael Barr; Anthony J. Massa (2006)."Introduction".Programming embedded systems: with C and GNU development tools. O'Reilly. pp.12.ISBN978-0-596-00983-0.4. ^Giovino, Bill."Micro controller.com - Embedded Systems supersite".5. ^Embedded.com - Under the Hood: Robot Guitar embeds autotuningBy David Carey, TechOnline EE Times (04/22/08, 11:10:00 AM EDT)Embedded Systems Design - Embedded.com6. ^Matthias Rehm, Nikolaus Bee, Elisabeth Andr,Wave Like an Egyptian - Accelerometer Based Gesture Recognition for Culture Specific Interactions, British Computer Society, 20077. ^Pavlovic, V., Sharma, R. & Huang, T. (1997),"Visual interpretation of hand gestures for human-computer interaction: A review", IEEE Trans. Pattern Analysis and Machine Intelligence., July, 1997. Vol. 19(7), pp. 677 -695.8. ^R. Cipolla and A. Pentland,Computer Vision for Human-Machine Interaction, Cambridge University Press, 1998,ISBN 978-0-521-62253-09. ^Ying Wu and Thomas S. Huang,"Vision-Based Gesture Recognition: A Review", In: Gesture-Based Communication in Human-Computer Interaction, Volume 1739 of Springer Lecture Notes in Computer Science, pages 103-115, 1999,ISBN 978-3-540-66935-7,doi:10.1007/3-540-46616-910. ^Alejandro Jaimesa and Nicu Sebe,Multimodal humancomputer interaction: A survey, Computer Vision and Image Understanding Volume 108, Issues 1-2, OctoberNovember 2007, Pages 116-134 Special Issue on Vision for Human-Computer Interaction,doi:10.1016/j.cviu.2006.10.01911. ^"ATIS Telecom Glossary 2007". atis.org. Retrieved 2008-03-16.12. ^Tsai, Allen."AT&T Releases Navigator GPS Service with Speech Recognition". Telecom Industry News. Retrieved 2 April 2008.13. ^abStory, Alfred Thomas (1904).A story of wireless telegraphy. New York, D. Appleton and Co..14. ^ab"Heinrich Rudolf Hertz". chem.ch.huji.ac.il. Retrieved 2008-03-16.15. ^J.C. Bose, Collected Physical Papers. New York, N.Y.: Longmans, Green and Co., 1927

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