DedicationWe dedicate our project to our Supervisor for his support and guidance that lead us to

fulfill our project. Than we dedicate our project to our parents who supported us

throughout our Educational career financially and morally.

ii

ACKNOWLEDGMENTBy the grace of Allah Almighty, who is the most merciful and beneficent! It is a

matter of great pleasure and privilege for us to complete this project under the

supervision of -----. We are also grateful to our Teachers, lab Engineers and

Technicians for their help and encouragement.

iii

ABSTRACT

Robots of the future should communicate with humans in a natural way. Hence, we

are especially interested in hand motion based gesture Robot . The purpose of this

study was to present a reliable means for human-computer interfacing based on hand

gestures made in three dimensions, which could be interpreted and adequately used in

controlling the movement of the Robot. We will have glove in which there will be

greoscope, arduino and transmitter while in the robot we will have the receiver which

will receiver the instructions from the transmitter moves according to the direction of

the hand. The Robot will move forward left and right according to the gestures of the

hand.

iv

TABLE OF CONTENTSACKNOWLEDGMENT.....................................................................iiiTABLE OF CONTENTS......................................................................vLIST OF ACRONYMS.......................................................................viChapter 1...............................................................................................1INTRODUCTION................................................................................11.1 Overview............................................................................................................1

1.2 Problem Statement.............................................................................................1

1.3 Specifications of proposed solution...................................................................1

1.4 Objectives of the Project....................................................................................2

1.5 WIRELESS GESTURE CONTROLLED ROBOT...........................................2

1.6 Applications of the project/research...................................................................3

1.8 Application of Gesture controlled Robot:..........................................................3

LIERATURE REVIEW........................................................................42.1 Related Technologies.........................................................................................4

2.2.1 ASUS Xtion / Primesense Carmine....................................................4

2.2 Glove..................................................................................................................5

2.3 H Bridge.............................................................................................................6

2.4 Gesture Control................................................................................................10

2.4 Robot................................................................................................................11

METHODOLOGIES AND IMPLEMENTATION............................123.1 Working model.................................................................................................12

4.2 Technology.......................................................................................................12

Chapter 4.............................................................................................15TOOLS AND TECHNIQUES............................................................154.1 Hardware Used With Technical Specifications...............................................15

4.1.1 RF transmitter and Receiver...............................................15

4.1.2 DC Motor..........................................................................................17

4.1.3 MOSFET........................................................................................18

4.1.4 Gyro Sensors.....................................................................................20

4.1.5 SPDT Relay.......................................................................................23

4.1.6 2N2222 Transistor............................................................................26

4.1.7 Diode................................................................................................27

v

4.1.8 AT mega 328 Microcontroller..................................................28

4.1.9 Arduino Uno..................................................................................29

4.1.10 Capacitors...................................................................................32

4.1.11 Resistor:...........................................................................................38

4.2 Software, Simulation Tool Used......................................................................43

4.2.1 Proteus...............................................................................................43

4.2.2 Eagle..................................................................................................43

CONCLUSION...................................................................................44REFRENCES......................................................................................45

vi

LIST OF ACRONYMS

ADC Analog to digital convertor

DAC Digital to analog convertor

DAQ Data Acquisition

AC Alternating Current

DC Direct Current

PCB Printed Circuit Board

USB Universal Serial Bus

CAM Computer Aided Manufacturing

PWM Pulse Width Modulation

vii

viii

ix

EEPROM Electrically Erasable Programmable Read Only Memory

x

Chapter 1

INTRODUCTION

Gesture Controlled Robot is a robot which can be controlled by simple gestures. The

user just needs to wear a gesture device which includes a sensor. The sensor will

record the movement of hand in a specific direction which will result in the movement

of the robot in the respective direction. The robot and the Gesture device are

connected wirelessly via radio waves. The wireless communication enables the user to

interact with the robot in a more friendly way.

1.1 OverviewRobotics is a current emerging technology in the field of science. A number of

universities in world are working in this field. Robotics is the new emerging booming

field, which will be of great use to society in the coming years. These days many

types of wireless robots are being developed and are put to varied applications and

uses.

1.2 Problem StatementA wireless data glove was developed to control a robot. Sensors mounted on the glove

send signals to a processing unit, worn on the user’s forearm that translates hand

postures into data. An RF transceiver, also mounted on the user, transmits the encoded

signals representing the hand postures and dynamic gestures to the robot via RF link.

Commands to control the robot’s mobility.

1.3 Specifications of proposed solution

Gesture Controlled robot is a kind of robot which can be controlled by  your hand

gestures not by old buttons.You just need to wear a small transmitting device in your

hand which included an acceleration meter.This will transmit an appropriate

command to the robot so that it can do whatever we want. The transmitting device

included a  ADC for analog to digital conversion and an encoder which is use to

encode the four bit data and then it will transmit by an RF Transmitter module.

1

At the receiving end an RF Receiver module receive's the encoded data and decode it

by and decoder . This data is then  processed by a microcontroller  and finally our

motor driver to control the motor's.  Now its time to break the task

in different module's to make the task easy and simple any project become easy  or

error free if it is done in different modules. As our project is already divided into two

different part transmitter and receiver. We will discuss both of them one by one.

1.4 Objectives of the ProjectOur objective is to make this device simple as well as cheap so that it could be mass

produced and can be used for a number of purposes.

1.5 WIRELESS GESTURE CONTROLLED ROBOT

A gesture is an action that has to be seen by someone else and has to convey some

piece of information. Gesture is usually considered as a movement of part of the body,

esp. a hand or the head, to express an idea or meaning.

gesture recognition technologies are much younger in the world of today. At this time

there is much active research in the field and little in the way of publicly available

implementations. Several approaches have been developed for sensing gestures and

controlling robots. Glove based technique is a well-known means of recognizing hand

gestures. It utilizes a sensor attached to a glove that directly measures hand

movements. A Gesture Controlled robot is a kind of robot which can be controlled by

hand gestures and not the old fashioned way by using buttons. The user just needs to

wear a small transmitting device on his hand which includes a sensor which is an

accelerometer in our case. Movement of the hand in a specific direction will transmit

a command to the robot which will then move in a specific direction. The transmitting

device includes a Comparator IC for assigning proper levels to the input voltages

from the accelerometer and an Encoder IC which is used to encode the four bit data

and then it will be transmitted by an RF Transmitter module. At the receiving end an

RF Receiver module will receive the encoded data and decode it by using a decoder

IC. This data is then processed by a microcontroller and passed onto a motor driver to

rotate the motors in a special configuration to make the robot move in the same

direction as that of the hand. 

2

1.6 Applications of the project/researchBy designing and implementing a faster hand gesture and a faster controller on the

Robots, the robots may be safer to use by users. Work is in progress on hand gesture

system are also using in vehicles and jets. Future scope of the project includes the

ability to control various household devices like TV, air-condition etc. Also the user

can control computers and mobile phones.

1.7 Project Plan

For the project we have 2 semester having 32 weeks. We divide our project into two

parts on the bases on semester. In first part we complete all the designing parameter

and made the selection of best components and then in 2nd part we made the hardware.

The time span of tasks and responsibilities of members are given below in the table.

We divide the semester into six parts and also divide the work into different phases.

1.8 Application of Gesture controlled Robot: In industries as robot to carry goods.

Automatic gaming toys.

Communication

Control of Mechanical systems

Sports

Feedback in Computer Based Learning environment

Chapter 2

3

LIERATURE REVIEW

2.1 Related Technologies

2.2.1 ASUS Xtion / Primesense Carmine

Before making a deal with Leap, ASUS had a gesture recognition camera known as

the Xtion Pro. This newer camera has several advantages over Microsoft’s Kinect

including lighter weight, smaller size, the ability to power on via USB alone, better

image quality and a color sensor (in the Xtion Live).

In theory, these advantages give the ASUS product an advantage over Microsoft, but

the Xtion never really took off. Microsoft’s classic advantage, size, has resulted in a

larger install base and generally better driver support; two factors that make

developers more inclined to use the Kinect. Also, the Xtion doesn’t have the

positioning motor found in Kinect, so it must be manually adjusted.

ASUS hasn’t said much about the Xtion lately, so it’s not clear if the device has a

future. The sensor is sold for just $119 with development software included, so those

who want an inexpensive gesture camera may find use for it.

4

Developers who are leery of the seemingly abandoned Xtion should instead check out

the Carmine. Made by Primesense, which developed the technology powering both

the Xtion and Kinect, the Carmine has nearly identical specifications. The price is

higher, at $200, but the platform is still in development and has better driver support.

Serious developers will find that well worth an extra $80.

2.2 Glove

The glove has gyros, arduino and transmitter . The gyros detect hand rotations. With

robot and control module the data-processing unit on the glove reads and analyzes the

sensor data and translates the raw data into control commands equivalent to those

produced by the robot’s . Then the dataprocessing unit sends the commands to the

controller wirelessly via radio frequency. The controller assembles all commands

from the data glove and other sources into a package and sends them to the robot for

execution. This architecture has the advantage of allowing traditional control of the

robot as well as conforming to the robot's existing interface.

Robotic glove houses the circuitry which controls the robotic arm. It consists of

Arduino Mega 2560 which is programmed in such a way that it transfers the required

data with the help of APC – 220 Module as well as it receives the data transmitted by

the robotic arm. The Gyroscope and Accelerometer installed takes the angles (alpha,

beta and gamma ) and acceleration in all three directions of the hand respectively,

sends the signals to the Arduino Mega via wires where the values are combined and

processed simultaneously. At the same time the Flex sensor is doing its job by

sending the degree of movement of the finger to the Arduino Mega. The processed

values are then transmitted from the Module (Trans-receiver ) to the robotic arm. The

module takes the feedback from the arm and sends the new processed signals to it.

2.3 H BridgeA H bridge is an electronic circuit that enables a voltage to be applied across a load in

either direction. These circuits are often used in robotics and other applications to allow

DC motors to run forwards and backwards.

5

The H-Bridge is designed to drive a motor clockwise and anticlockwise.  To reverse a

motor, the supply must be reversed and this is what the H-Bridge does. 

An H-Bridge can be made with SWITCHES, RELAYS, TRANSISTORS or

MOSFETS. 

Do not make circuit "A." It can easily create a SHORT-CIRCUIT. It is only a

demonstration circuit.

Switch A and D will make the motor rotate clockwise.

Switch B and C will make the motor rotate anti-clockwise.

Switch A and B will create a BRAKE. 

Do not close switch A and C at the same time. 

Do not close switch B and D at the same time. 

H-Bridge with a relay:

6

The motor is active at all times. Push the button to reverse the direction of rotation. 

H-Bridge with 2 relays:

This circuit has an advantage. It has FORWARD, OFF, REVERSE and BRAKE (off

BRAKE). The relays are single-pole change-over.

BRIEF H-BRIDGE THEORY OF OPERATION

We take a battery; hook the positive side to one side of your DC motor. Then we

connect the negative side of the battery to the other motor lead. The motor spins

forward. If we swap the battery leads the motor spins in reverse.

7

Now lets say we want a Micro Controller Unit (MCU) to control the motor, how would

we did it Well, for starters we get a device that would act like a solid state switch, a

transistor, and hook it up the motor.

We connect up these relay circuits, remember to put a diode across the coil of the relay.

This will keep the spike voltage (back EMF), coming out of the coil of the relay, from

getting into the MCU and damaging it. The anode, which is the arrow side of the diode,

should connect to ground. The bar, which is the Cathode side of the diode, should

connect to the coil where the MCU connects to the relay.

If we connect this circuit to a small hobby motor we can control the motor with a

processor (MCU, etc.) Applying a logical one, (+12 Volts in our example) to point A

causes the motor to turn forward. Applying a logical zero, (ground) causes the motor to

stop turning (to coast and stop).

Hook the motor up in this fashion and the circuit turns the motor in reverse when you

apply a logical one (+12Volts) to point B. Apply a logical zero, which is usually a

ground, causes the motor to stop spinning.

If we hook up these circuits we can only get the motor to stop or turn in one direction,

forward for the first circuit or reverse for the second circuit.

Motor Speed

We can also pulse the motor control line, (A or B) on and off. This powers the motor in

short burst and gets varying degrees of torque, which usually translates into variable

motor speed.

8

But if we want to be able to control the motor in both forward and reverse with a

processor, we will need more circuitry. We will need an H-Bridge. Notice the "H"-

looking configuration in the next graphic. Relays configured in this fashion make an H-

Bridge. The "high side drivers" are the relays that control the positive voltage to the

motor. This is called sourcing current.

The "low side drivers" are the relays that control the negative voltage to sink current to

the motor. "Sinking current" is the term for connecting the circuit to the negative side of

the power supply, which is usually ground.

So, you turn on the upper left and lower right circuits, and power flows through the

motor forward, i.e.: 1 to A, 0 to B, 0 to C, and 1 to D.

9

2.4 Gesture ControlGestures control Robots are extensively employed in human non-verbal

communication which works with our hand gestures. This project enhances this work

with the development of the wireless mechanism for control of the locomotion. This

Robot is mainly divided into two practical parts:

1.Transmitter – The gesture device.

2. Receiver – The Robot.

They allow to express orders (e.g. “stop”), mood state (e.g.forward gesture), or to

transmit some basic cardinal information. Thus, it seems convenient that human

Robots interfaces incorporate hand gesture recognition capabilities. For instance, we

would like to have the possibility of transmitting simple orders to personal robots

using hand gestures. The recognition of hand gestures requires both hand’s detection

and gesture’s recognition. Both tasks are very challenging, mainly due to the

variability of the possible hand gestures (signs), and because hands are complex,

deformable objects (a hand has more than 25 degrees of freedom, considering fingers,

wrist and elbow joints) that are very difficult to detect in dynamic environments with

cluttered backgrounds and variable illumination. Several hand detection and hand

gesture recognition systems have been proposed. Early systems usually require

markers or colored gloves to make the recognition easier.Gesture controlled Robot

systems have been studied extensively in recent years, considering that Robots will

10

play an important role in the future. The use of intelligent robots encourages the view

of the machine as a partner in communication rather than as a tool. In the near future,

robots will interact closely with a group of humans in their everyday environment in

the field of entertainment, recreation, health-care,nursing, etc.

2.4 Robot

A robot is usually an electro-mechanical machine that can perform tasks

automatically. Some robots require some degree of guidance, which may be done

using a remote control or with a computer interface. Robots can be autonomous, semi-

autonomous or remotely controlled. Robots have evolved so much and are capable of

mimicking humans that they seem to have a mind of their own.

HUMAN MACHINE INTERACTION

An important aspect of a successful robotic system is the Human-Machine

interaction. In the early years the only way to communicate with a robot was to

program which required extensive hard work. With the development in science and

robotics, gesture based recognition came into life. Gestures originate from any bodily

motion or state but commonly originate from the face or hand. Gesture recognition

can be considered as a way for computer to understand human body language.

11

Chapter 3

METHODOLOGIES AND IMPLEMENTATION

3.1 Working modelImplementation of this proposed problem mainly involves two steps. They are gesture

recognition and controlling direction of wheelchair using microcontroller based on the

received gesture commands. The accelerometer which convert the hand position into

3-Dimensional Output. The values obtained from the accelerometer are analog values

which should be further converted into digital values so they can be used by the

microcontroller. The accelerometer analog outputs are converted into digital .

ADC converts the data from sensor and proceeds to the microcontroller for further

conversion and calibration.

4.2 TechnologyGestures have recently become attractive for interaction with consumer electronics

and mobile devices by the use of gesture recognition technique via the accelerometer

the movement of the Robot will be controlled. The primary goal of gesture

recognition research is to create a system which can identify specific human gestures

and use them to convey information or for device control. Gesture Recognition is the

act of interpreting motions to determine such intent. There are different types of

gestures such as hand, face (emotion), body gestures etc. To identify and recognize

these gestures there are different ways of gesture recognition such as:

1)hand and arm gestures:

recognition of hand poses, sign languages, and entertainment applications (allowing

children to play and interact in virtual environ ments).

2)head and face gestures: Some examples are

a)nodding or head shaking,

b) direction of eye gaze,

c)raising the eyebrows,

d) opening and closing the mouth,

12

e) winking,

f) flaring the nostrils,

e) looks of surprise, happiness, disgust, fear, sadness, and many others represent head

and face gestures.

3)body gestures: involvement of full body motion, as in

a) tracking movements of two people having a conversation,

b) analyzing movements of a dancer against the music being played and the rhythm,

c) recognizing human gaits for medical rehabilitation and athletic training.

13

14

Chapter 4

TOOLS AND TECHNIQUES.

4.1 Hardware Used With Technical Specifications

4.1.1 RF transmitter and Receiver

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.

This RF module comprises of an RF Transmitter and an RF Receiver. The

transmitter/receiver (Tx/Rx) pair operates at a frequency of 434 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 alongwith 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.

15

4.1.9.1 Pin Description:  

RF Transmitter

Pin No Function Name1 Ground (0V) Ground2 Serial data input pin Data3 Supply voltage; 5V Vcc4 Antenna output pin ANT

  

RF Receiver

Pin No Function Name1 Ground (0V) Ground2 Serial data output pin Data3 Linear output pin; not connected NC4 Supply voltage; 5V Vcc5 Supply voltage; 5V Vcc6 Ground (0V) Ground7 Ground (0V) Ground8 Antenna input pin ANT

16

4.1.2 DC Motor

A dc motor uses electrical energy to produce mechanical energy, very typically through the interaction of magnetic fields and current-carrying conductors. The reverse process, producing electrical energy from mechanical energy, is accomplished by an alternator, generator or dynamo. Many types of electric motors can be run as generators, and vice versa. The input of a DC motor is current/voltage and its output is torque (speed).A machine that converts DC power into mechanical power is known as a DC motor. Its operation is based on the principle that when a current carrying conductor is placed in a magnetic field, the conductor experiences a mechanical force. DC motors have a revolving armature winding but non-revolving armature magnetic field and a stationary field winding or permanent magnet. Different connections of the field and armature winding provide different speed/torque regulation features. The speed of a DC motor can be controlled by changing the voltage applied to the armature or by changing the field current. 

17

The DC motor has two basic parts: the rotating part that is called the armature and the stationary part that includes coils of wire called the field coils. The stationary part is also called the stator. Figure shows a picture of a typical DC motor, Figure shows a picture of a DC armature, and Fig shows a picture of a typical stator. From the picture you can see the armature is made of coils of wire wrapped around the core, and the core has an extended shaft that rotates on bearings. You should also notice that the ends of each coil of wire on the armature are terminated at one end of the armature. The termination points are called the commentator, and this is where the brushes make electrical contact to bring electrical current from the stationary part to the rotating part of the machine. 

4.1.3 MOSFET

MOSFET (metal-oxide semiconductor field-effect transistor, pronounced MAWS-

feht ) is a special type of field-effect transistor ( FET ) that works by electronically

varying the width of a channel along which charge carriers ( electron s or hole s) flow.

The wider the channel, the better the device conducts. The charge carriers enter the

channel at the source , and exit via the drain . The width of the channel is controlled

by the voltage on an electrode called thegate , which is located physically between the

source and the drain and is insulated from the channel by an extremely thin layer of

metal oxide.

There are two ways in which a MOSFET can function. The first is known as depletion

mode . When there is no voltage on the gate, the channel exhibits its

maximum conductance . As the voltage on the gate increases (either positively or

negatively, depending on whether the channel is made of P-type or N-

type semiconductor material), the channel conductivity decreases. The second way in

which a MOSFET can operate is called enhancement mode . When there is no voltage

on the gate, there is in effect no channel, and the device does not conduct. A channel

18

is produced by the application of a voltage to the gate. The greater the gate voltage,

the better the device conducts.

The MOSFET has certain advantages over the conventional junction FET, or JFET.

Because the gate is insulated electrically from the channel, no current flows between

the gate and the channel, no matter what the gate voltage (as long as it does not

become so great that it causes physical breakdown of the metallic oxide layer). Thus,

the MOSFET has practically infinite impedance . This makes MOSFETs useful for

power amplifiers. The devices are also well suited to high-speed switching

applications. Some integrated circuits ( IC s) contain tiny MOSFETs and are used in

computers.

Because the oxide layer is so thin, the MOSFET is susceptible to permanent damage

by electrostatic charges. Even a small electrostatic buildup can destroy a MOSFET

permanently. In weak-signal radio-frequency ( RF ) work, MOSFET devices do not

generally perform as well as other types of FET.

Metal–oxide–semiconductor structure

The traditional metal–oxide–semiconductor (MOS) structure is obtained by growing a

layer of silicon dioxide (SiO2) on top of a silicon substrate and depositing a layer of

metal or polycrystalline silicon (the latter is commonly used). As the silicon dioxide is

a dielectricmaterial, its structure is equivalent to a planar capacitor, with one of the

electrodes replaced by a semiconductor.

When a voltage is applied across a MOS structure, it modifies the distribution of

charges in the semiconductor. If we consider a p-type semiconductor (with   the

density of acceptors, p the density of holes; p = NA in neutral bulk), a positive

voltage,  , from gate to body (see figure) creates a depletion layer by forcing the

positively charged holes away from the gate-insulator/semiconductor interface,

leaving exposed a carrier-free region of immobile, negatively charged acceptor ions

(see doping (semiconductor)). If   is high enough, a high concentration of

negative charge carriers forms in an inversion layer located in a thin layer next to the

interface between the semiconductor and the insulator. Unlike the MOSFET, where

the inversion layer electrons are supplied rapidly from the source/drain electrodes, in

the MOS capacitor they are produced much more slowly by thermal generation

19

through carrier generation and recombination centers in the depletion region.

Conventionally, the gate voltage at which the volume density of electrons in the

inversion layer is the same as the volume density of holes in the body is called

the threshold voltage. When the voltage between transistor gate and source (VGS)

exceeds the threshold voltage (Vth), it is known asoverdrive voltage.

This structure with p-type body is the basis of the n-type MOSFET, which requires

the addition of an n-type source and drain regions.

4.1.4 Gyro Sensors

A gyro sensor, angular rate sensor or angular velocity sensor is a device that can sense

angular velocity. Gyro sensors can sense rotational motion and changes in orientation

and therefore augment motion. Vibration gyro sensors can sense angular velocity due

to the Coriolis force which is applied to a vibrating element. This motion produces a

potential difference from which angular velocity is sensed. The angular velocity is

converted into an electrical signal output.

Gyro sensors, also known as angular rate sensors or angular velocity sensors, are

devices that sense angular velocity.

20

Gyro Sensor Types

Gyro sensors come in a variety of types. Here, different types are plotted by size and

performance.

In recent years vibration gyro sensors have found their way into camera-shake

detection systems for compact video and still cameras, motion sensing for video

games, and vehicle electronic stability control (anti-skid) systems, among other

things.

There are several different kinds of gyro sensors. At Future Electronics we stock

many of the most common types categorized by output type, supply voltage, supply

current, sensing range, operating temperature range and packaging type. The

parametric filters on our website can help refine your search results depending on the

required specifications.

The most common sizes for supply voltage are 2.7 to 3.6 V. We also carry gyro

sensors with supply voltage up to 5 V. The output type can be analog, digital, linear or

ratiometric, with the most common chips having an analog output.

21

Vibration Gyro Sensors

Vibration gyro sensors sense angular velocity from the Coriolis force applied to a

vibrating element. For this reason, the accuracy with which angular velocity is

measured differs significantly depending on element material and structural

differences. Here, we briefly describe the main types of elements used in vibration

gyro sensors.

Types of elements used in vibration gyro sensors

Vibration gyro sensor manufacturers are using a variety of materials and structures in

an effort to devise compact, high-accuracy gyro sensors that have good

characteristics, including:

• scale factor

• temperature-frequency coefficient

• compact size

• shock resistance

• stability

• noise characteristics

Gyro Sensors from Future Electronics

Future Electronics has a complete selection of gyro sensors from several chip

manufacturers that can be used as a MEMS gyro sensor or a 3 axis gyro sensor,

among other uses. Simply choose from the gyro sensor technical attributes below and

your search results will quickly be narrowed in order to match your specific gyro

sensor application needs.

If you have a preferred brand, we deal with Bosch, Murata and STMicroelectronics as

manufacturers. You can easily refine your gyro sensor product search results by

clicking your preferred gyro sensor brand below from our list of manufacturers.

Applications for Gyro Sensors:

The main applications for gyro sensors are:

Angular velocity sensing: to sense the amount of angular velocity produced, which is

the motion itself. An example would be the sensing of athletic movement.

22

Angle sensing: to sense the angular velocity produced by the movement of the sensor

itself. Angles are detected by a CPU. Thus, the moved angle is fed to and reflected in

an application. Examples are car navigation systems, video game controllers and

mobile phones.

Control mechanisms: to senses the vibration produced by external factors. This

vibration data is then transmitted as electrical signals to a CPU. This is used in

correcting the balance or orientation of an object. Some examples include camera-

shake correction and vehicle control.

Choosing the Right Gyro Sensor:

When you are looking for the right gyro sensors, you can filter the results by various

attributes with the FutureElectronics.com parametric search: by Sensing Range

(±2000 °/s, ±300 °/s, ±100 °/s, 500 °/s,… ), Output Type (Analog Output, Digital

Output, Linear, Ratiometric) and Supply Current (from 4.2 mA to 10 mA) to name a

few. You will be able to find the right high speed op amps to design a 3 axis gyro

sensor or mems gyro sensor.

Gyro Sensors in Production Ready Packaging or R&D Quantities

If the quantity of gyro sensors required is less than a full reel, we offer to customers

many of our gyro sensor products in tube, tray or individual quantities that will help

you avoid unneeded surplus.

In addition, Future Electronics offers its clients a unique bonded inventory program

designed to eliminate potential problems that could arise from an unpredictable

supply of products containing raw metals and products with long or erratic lead times.

Talk with your nearest Future Electronics branch and find out more on how you and

your company can avoid possible shortages.

4.1.5 SPDT Relay

A relay is an electrically operated switch used to isolate one electrical circuit from

another. In its simplest form, a relay consists of a coil used as an electromagnet to

open and close switch contacts. Since the two circuits are isolated from one another, a

lower voltage circuit can be used to trip a relay, which will control a separate circuit

that requires a higher voltage or amperage. Relays can be found in early telephone

23

exchange equipment, in industrial control circuits, in car audio systems, in

automobiles, on water pumps, in high-power audio amplifiers and as protection

devices.

A single pole double throw (SPDT) relay configuration switches one common pole to

two other poles, flipping between them. This correlates to the following in the relay:

Figure 4.10 SPDT Relay

Terminal Descriptions

COIL This is one end of the coil.COIL- This is the other end of the coil. These are the

terminals where you apply voltage to in order to give power to the coils (which then

will close the switch). Polarity does not matter. One side gets positive voltage and the

other side gets negative voltage. Polarity only matters if a diode is used.

NO- This is Normally Open switch. This is the terminal where you connect the device

that you want the relay to power when the relay is powered, meaning when the COIL

receives sufficient voltage. The device connected to NO will be off when the relay has

no power and will turn on when the relay receives power. 

NC- This is the Normally Closed Switch. This is the terminal where you connect the

device that you want powered when the relay receives no power. The device

connected to NC will be on when the relay has no power and will turn off when the

relay receives power. COM- This is the common of the relay. If the relay is powered

and the switch is closed, COM and NO have continuity. If the relay isn't powered and

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the switch is open, COM and NC have continuity. This is the terminal of the relay

where you connect the first part of your circuit to.

Now that we know what each terminal pin represents, we now wire it to a circuit for it

to do a real-world function. We're going to connect a single pole double throw relay

to a circuit to light up a LED. When the relay isn't powered, the red LED is lit and

stays on. When the relay is powered, the red LED shuts off and the green LED lights

up.

This is the circuit below:

 

Since the relay is rated for 12V, it should receive 12 volts in order to power on. It may

work with less voltage, but 12V is really what it should receive. This goes into either

side of the COIL terminals. Even if you switched the positive and negative voltage of

the power supply, it should work exactly the same.

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The COM terminal of the relay gets connected to the first part of the circuit. If there is

no first part of the circuit, this terminal can be left open. In this case, the first part of

the circuit is a 5-volt power supply to light the red LED.

The NC terminal of the relay gets power even when the relay isn't powered. This

means that as long as the 5-volt power supply is on, the red LED will be lit.

The NO temrinal of the relay gets power only when the relay is powered. When the

relay receives 12 volts of power, the relay's snaps from the NC position to the NO

position. The red LED now shuts off and the green LED turns on. 

4.1.6 2N2222 Transistor

The 2N222 transistor is a common negative-positive-negative (NPN) bipolar junction

transistor (BJT) that finds use in many different kinds of electronic equipment. It is

used for both analog signal amplification and switching applications. The functioning

parts of the 2N2222 transistor are enclosed in what is known as a TO-18 package,

which resembles a small metal can. The broad range of uses for the 2N2222 transistor,

and its small size, make it and its variants the most widely used transistors in

electronics.

The functioning portion of the 2N2222 transistor is a NPN BJT construct. The

2N2222 transistor is made of either germanium or silicon that has been saturated with

either a positively or negatively changed material in a process called “doping.” The

2N2222 has a positively charged section sandwiched between two negatively charged

sections. The resulting two connections between the three sections are where the

2N2222 derives the name “bipolar junction transistor.” The materials used are

arranged in the order of negative, positive, then negative, so the device is also said to

be a NPN transistor.

The 2N2222 has three wire leads used to solder it to circuit boards: the collector,

the emitter, and the base. When an electronic signal is present at the transistor’s

collector, applying a signal to the transistor’s base will cause a signal to emit from the

device’s emitter. In this way, the 2N2222 is often used to switch signals on and off.

The switching abilities of the 2N2222 transistor also make it useful as a simple “and”

gate. When used in this capacity, the transistor will only send a signal when two

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separate signals are present: one at its collector and one at its base. This allows the

2N2222 to be used to automatically control signal flow in a circuit depending on what

signals are, or are not, present.

In amplification applications, the 2N2222 receives an analog signal, such as an audio

signal, through its collector and a separate signal is applied to its base. The output at

the transistor’s emitter will then be identical to the collector signal with the exception

that it increases in power by an amount proportional to the signal applied to its base.

Additionally, varying the signal applied to the base will vary the amplification of the

signal leaving the emitter.

Operational characteristics make the 2N2222 a low- to medium-current (up to 600

milliamps), low-power (up to 625 milliwatts), medium-voltage (up to 40 volts)

device. Though these parameters may seem to limit the 2N2222’s usefulness, the

2N2222 is perfect for a host of signal manipulation and handling applications prior to

high-power amplification. 2N2222 transistors are also used to condition signals before

and after application to more advanced digital devices.

While the 2N2222 was the first of its kind, it has spawned a number of variants

collectively called “2N2222 type” transistors, because they all share functional-

construction and operational characteristics identical to the original 2N2222 transistor.

Chief among these variants is the P2N2222 transistor, which is enclosed in a small

black TO-92 package made of either epoxy or plastic. The combination of the large

number of uses for the 2N2222 and the cost-effective TO-92 package has made the

P2N2222 the least expensive and most used transistor in electronics.

4.1.7 Diode

The most basic property of a junction diode is that it conducts an electric current in

one direction and blocks it in the other. This behavior arises from the electrical

characteristics of a junction, called a p-n junction. Fabricated within a semiconductor

crystal. The most commonly used semiconductor material is silicon. The junction

diode is useful in a wide variety of applications including the rectification of ac

signals (producing dc from ac), the detection of radio signals, the conversion of solar

power to electricity, and in the generation and detection of light. It also finds use in a

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variety of electronic circuits as a switch, as a voltage reference or even as a tunable

capacitor. The p-n junction is also the basic building block of a host of other

electronic devices, of which the most well-known is the junction transistor.

4.1.8 AT mega 328 Microcontroller

The ATmega328 is a low-power CMOS 8-bit microcontroller based on the

AVR Enhanced RISC architecture. By executing powerful instructions in a single

clock cycle, the ATmega328 achieves throughputs approaching 1 MIPS per MHz

allowing the system designed to optimize power consumption versus processing

speed .

The AVR core combines a rich instruction set with 32 general purpose working

registers. All the 32 registers are directly connected to the Arithmetic Logic Unit

(ALU), allowing two independent registers to be accessed in one single instruction

executed in one clock cycle. The resulting architecture is more code efficient while

achieving throughputs up to ten times faster than conventional CISC microcontrollers.

The features of different components are given in the following:

• High Performance, Low Power Atmel®AVR® 8-Bit Microcontroller Family

• Advanced RISC Architecture

Powerful Instructions - Most Single Clock Cycle Execution 32 x 8 General

Purpose Working Registers

Fully Static Operation

Up to 20 MIPS Throughput at 20MHz On-chip 2-cycle Multiplier

• High Endurance Non-volatile Memory Segments

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4/8/16/32KBytes of In-System Self-Programmable Flash memory

256/512/512/1KBytes EEPROM

512/1K/1K/2KBytes Internal SRAM

Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

Optional Boot Code Section with Independent Lock Bits In-System

Programming by On-chip Boot Program

Programming Lock for Software Security

Up to 64 sense channels

Peripheral Features

Two 8-bit Timer/Counters

One 16-bit Timer/Counter

Real Time Counter with Separate scillator

Six PWM Channels

8-channel 10-bit ADC in TQFP and QFN/MLF package

• Special Microcontroller Features

Power-on Reset and Programmable Brown-out Detection Internal

Calibrated Oscillator

External and Internal Interrupt Source I/O and Packages

23 Programmable I/O Lines

28-pin PDIP, 32-lead TQFP,28-pad QFN/MLF and 32-pad

QFN/MLF

Operating Voltage:

1.8 - 5.5V

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4.1.9 Arduino Uno

Arduino is a popular open-source single-board microcontroller, descendant of the

opensource Wiring platform, designed to make the process of using electronics in

multidisciplinary projects more accessible. The hardware consists of a simple open

hardware design for the Arduino board with an Atmel AVR processor and onboard

input/output support. The software consists of a standard programming language

compiler and the boot loader that runs on the board. Arduino hardware is programmed

using a Wiring-based language (syntax and libraries), similar to C++ with some slight

simplifications and modifications, and a Processingbased integrated development

environment. Current versions can be purchased pre-assembled;. Additionally,

variations of the Italianmade Arduino with varying levels of compatibility have been

released by third parties; some of them are programmed using the Arduino

software.The Arduino project received an honorary mention in the Digital

Communities category at the 2006 Prix Ars Electronica. An Arduino board consists of

an 8-bit Atmel AVR microcontroller with complementary components to facilitate

programming and incorporation into other circuits. An important aspect of the

Arduino is the standard way that connectors are exposed, allowing the CPU board to

be connected to a variety of interchangeable add-on modules known as shields.

Official Arduinos have used the megaAVR series of chips, specifically the ATmega8,

ATmega168, ATmega328, ATmega1280, and ATmega2560. A handful of other

processors have been used by Arduino compatibles. Most boards include a 5 volt

linear regulator and a 16 MHz crystal oscillator (or ceramic resonator in some

variants), although some designs such as the LilyPad run at 8 MHz and dispense with

the onboard voltage regulator due to specific form-factor restrictions. An Arduino's

microcontroller is also pre-programmed with a boot loader that simplifies uploading

of programs to the on-chip flash memory, compared with other devices that typically

need an external programmer. At a conceptual level, when using the Arduino software

stack, all boards are programmed over an RS-232 serial connection, but the way this

is implemented varies by hardware version. Serial Arduino boards contain a simple

inverter circuit to convert between RS-232- level and TTL-level signals. Current

Arduino boards are programmed via USB, implemented using USB-to-serial adapter

chips such as the FTDI FT232. Some variants, such as the Arduino Mini and the

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unofficial Boarduino, use a detachable USB-to-serial adapter board or cable,

Bluetooth or other methods. (When used with traditional microcontroller tools instead

of the Arduino IDE, standard AVR ISP programming is used. The Arduino board

exposes most of the microcontroller's I/O pins for use by other circuits. The

Diecimila, now superseded by the Duemilanove, for example, provides 14 digital I/O

pins, six of which can produce pulse-width modulated signals, and six analog inputs.

These pins are on the top of the board, via female 0.1 inch headers. Several plug-in

application shields are also commercially available. The Arduino Nano, and Arduino-

compatible Bare Bones Board and Boarduino boards provide male header pins on the

underside of the board to be plugged into solderless breadboards.

History of Arduino UNO

The project began in Ivrea, Italy (the site of the computer company Olivetti), in 2005

to make a device for controlling student-built interaction design projects less

expensive than other prototyping systems available at the time. As of May 2011, more

than 300,000 Arduino units are "in the wild." Founders Massimo Banzi and David

Cuartielles named the project after Arduin of Ivrea, the main historical character of

the town. "Arduino" is an Italian masculine first name, meaning "strong friend". The

English version of the name is "Hardwin". The Arduino project is a fork of the open-

source Wiring Platform. Wiring was created by Colombian artist and programmer

Hernando Barragán as a master's thesis at the Interaction Design Institute Ivrea under

the supervision of Massimo Banzi and Casey Reas. Furthermore, Wiring is based on

Processing and its integrated development environment created by Casey Reas and

Ben Fry. “Arduino was built around the Wiring project of Hernando Barragan. Wiring

was Hernando's thesis project at the Interaction Design Institute Ivrea. It was intended

to be an electronics version of Processing that used our programming environment

and was patterned after the Processing syntax. It was supervised by myself and

Massimo Banzi, an Arduino founder. I don't think Arduino would exist without

Wiring and I don't think Wiring would exist without Processing. And I know

Processing would certainly not exist without Design By Numbers andJohn Maeda.”

Basic Functions of Arduino Uno

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

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powerup or reset of the Arduino board. After creating a setup() function, the loop()

function does precisely what its name suggests, and loops consecutively, allowing

your program to change and respond as it runs. Code in the loop() section of your

sketch is used to actively control the Arduino board. The code below won't actually

do anything, but it's structure is useful for copying and pasting to get you started on

any sketch of your own. It also shows you how to make comments in your code. Any

line that starts with two slashes (//) will not be read by the compiler, so you can write

anything you want after it. Commenting your code like this can be particularly helpful

in explaining, both to yourself and others, how your program functions step by step.

void setup()

{ // put your setup code here, to run once: }

void loop() { // put your main code here, to run repeatedly: }

setup()

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 board.

loop()

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.

4.1.10 Capacitors

A capacitor (formerly known as condenser) is a passive electronic component consisting of a pair of conductors separated by a dielectric (insulator). When there is a potential difference (voltage) across the conductors a static electric field develops in the dielectric that stores energy and produces a mechanical force between the conductors. An ideal capacitor is characterized by a single constant value, capacitance, measured in farads. This is the ratio of the

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electric charge on each conductor to the potential difference between them.

Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies and for many other purposes.

The effect is greatest when there is a narrow separation between large areas of conductor, hence capacitor conductors are often called "plates", referring to an early means of construction. In practice the dielectric between the plates passes a small amount of leakage current and also has an electric field strength limit, resulting in a breakdown voltage, while the conductors and leads introduce an equivalent series resistance.

TYPES OF CAPACITORS

Dielectric

Dielectric Capacitors are usually of the variable type such as used for tuning transmitters, receivers and transistor radios. They have a set of fixed plates and a set of moving plates that mesh with the fixed plates and the position of the moving plates with respect to the fixed plates determines the overall capacitance. The capacitance is generally at maximum when the plates are fully meshed. High voltage type tuning capacitors have relatively large

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spacings or air-gaps between the plates with breakdown voltages reaching many thousands of volts.

Variable Capacitor Symbols

As well as the continuously variable types, preset types are also available called Trimmers. These are generally small devices that can be adjusted or "pre-set" to a particular capacitance with the aid of a screwdriver and are available in very small capacitances of 100pF or less and are non-polarized.

2. Film Capacitors

Film Capacitors are the most commonly available of all types of capacitors, consisting of a relatively large family of capacitors with the difference being in their dielectric properties. These include polyester (Mylar), polystyrene, polypropylene, polycarbonate, metallized paper, teflon etc. Film type capacitors are available in capacitance ranges from 5pF to 100uF depending upon the actual type of capacitor and its voltage rating. Film capacitors also come in an assortment of shapes and case styles which include:

Wrap & Fill (Oval & Round)  -  where the capacitor is wrapped in a tight plastic tape and have the ends filled with epoxy to seal them.

Epoxy Case (Rectangular & Round)  -  where the capacitor is encased in a moulded plastic shell which is then filled with epoxy.

 

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Metal Hermetically Sealed (Rectangular & Round)  -  where the capacitor is encased in a metal tube or can and again sealed with epoxy.

with all the above case styles available in both Axial and Radial Leads.

Examples of film capacitors are the rectangular metallized film and cylindrical film & foil types as shown below.

Radial Lead Type

Axial Lead Type

The film and foil types of capacitors are made from long thin strips of thin metal foil with the dielectric material sandwiched together which are wound into a tight roll and then sealed in paper or metal

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tubes. These film types require a much thicker dielectric film to reduce the risk of tears or punctures in the film, and is therefore more suited to lower capacitance values and larger case sizes.

Metallized foil capacitors have the conductive film metallized sprayed directly onto each side of the dielectric which gives the capacitor self-healing properties and can therefore use much thinner dielectric films. This allows for higher capacitance values and smaller case sizes for a given capacitance. Film and foil capacitors are generally used for higher power and more precise applications.

3. Ceramic Capacitors

Ceramic Capacitors or Disc Capacitors as they are generally called, are made by coating two sides of a small porcelain or ceramic disc with silver and are then stacked together to make a capacitor. For very low capacitance values a single ceramic disc of about 3-6mm is used. Ceramic capacitors have a high dielectric constant (High-K) and are available so that relatively high capacitances can be obtained in a small physical size. They exhibit large non-linear changes in capacitance against temperature and as a result are used as de-coupling or by-pass capacitors as they are also non-polarized devices. Ceramic capacitors have values ranging from a few picofarads to one or two microfarads but their voltage ratings are generally quite low.

Ceramic types of capacitors generally have a 3-digit code printed onto their body to identify their capacitance value. For example, 103 would indicate 10 x 103pF which is equivalent to 10,000 pF or 0.01μF. Likewise, 104 would indicate 10 x 104pF which is equivalent to 100,000 pF or 0.1μF and so on. Letter codes are sometimes used to indicate their tolerance value such as: J = 5%, K = 10% or M = 20% etc.

4. Electrolytic Capacitors

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Electrolytic Capacitors are generally used when very large capacitance values are required. Here instead of using a very thin metallic film layer for one of the electrodes, a semi-liquid electrolyte solution in the form of a jelly or paste is used which serves as the second electrode (usually the cathode). The dielectric is a very thin layer of oxide which is grown electro-chemically in production with the thickness of the film being less than ten microns. This insulating layer is so thin that it is possible to make large value capacitors of a small size. The majority of electrolytic types of capacitors are Polarized, that is the voltage applied to the capacitor terminals must be of the correct polarity as an incorrect polarization will break down the insulating oxide layer and permanent damage may result.

Electrolytic Capacitors are generally used in DC power supply circuits to help reduce the ripple voltage or for coupling and decoupling applications. Electrolytic's generally come in two basic forms; Aluminum Electrolytic and Tantalum Electrolytic capacitors.

Electrolytic Capacitor

1. Aluminium Electrolytic Capacitors

There are basically two types of Aluminium Electrolytic Capacitor, the plain foil type and the etched foil type. The thickness of the aluminium oxide film and high breakdown voltage give these capacitors very high capacitance values for their size. The etched foil type differs from the plain foil type in that the aluminium oxide on the anode and cathode foils has been chemically etched to increase its surface area and permittivity. This gives a smaller sized

37

capacitor than a plain foil type of equivalent value but has the disadvantage of not being able to withstand high AC currents compared to the plain type. Also their tolerance range is quite large up to 20%. Etched foil electrolytic's are best used in coupling, DC blocking and by-pass circuits while plain foil types are better suited as smoothing capacitors in power supplies. Typical values of capacitance range from 1uF to 47000uF. Aluminium Electrolytic's are "polarized" devices so reversing the applied voltage on the leads will cause the insulating layer within the capacitor to be destroyed along with the capacitor, "so be aware".

2. Tantalum Electrolytic Capacitors

Tantalum Electrolytic Capacitors or Tantalum Beads, are available in both wet (foil) and dry (solid) electrolytic types with the dry or solid tantalum being the most common. Solid tantalums use manganese dioxide as their second terminal and are physically smaller than the equivalent aluminium capacitors. The dielectric properties of tantalum oxide is also much better than those of aluminium oxide giving a lower leakage currents and better capacitance stability which makes them suitable for timing applications. Also tantalum capacitors although polarized, can tolerate being connected to a reverse voltage much more easily than the Aluminium types but are rated at much lower working voltages. Typical values of capacitance range from 47nF to 470uF.

Aluminium & Tantalum Electrolytic Capacitor

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4.1.11 Resistor:

A resistor is a two-terminal electronic component that produces a voltage across its terminals that is proportional to the electric current passing through it in accordance with Ohm's law:

V = IRResistors are elements of electrical networks and electronic circuits and are ubiquitous in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel/chrome).The primary characteristics of a resistor are the resistance, the tolerance, maximum working voltage and the power rating. Other characteristics include temperature coefficient, noise, and inductance. Less well-known is critical resistance, the value below which power dissipation limits the maximum permitted current flow, and above which the limit is applied voltage. Critical resistance is determined by the design, materials and dimensions of the resistor.Resistors can be integrated into hybrid and printed circuits, as well as integrated circuits. Size, and position of leads (or terminals) are relevant to equipment designers; resistors must be physically large enough not to overheat when dissipating their power.Resistors produce a voltage drop across themselves when an electrical current flows through them because they obey Ohm's Law, and different values of resistance produces different values of current or voltage. This can be very useful in Electronic circuits by

39

controlling or reducing either the current flow or voltage produced across them. There are many different Resistor Types and they are produced in a variety of forms because their particular characteristics and accuracy suit certain areas of application, such as High Stability, High Voltage, High Current etc, or are used as general purpose resistors where their characteristics are less of a problem. Some of the common characteristics associated with the humble resistor are; Temperature Coefficient, Voltage Coefficient, Noise, Frequency Response, Power as well as Temperature Rating, Physical Size and Reliability.

resistors can be classified into four broad groups;1. Carbon Composition Resistor - Made of carbon dust or graphite paste, low wattage values2. Film or Cermet Resistor - Made from conductive metal oxide paste, very low wattage values3. Wire-Wound Resistors. - Metallic bodies for heatsink mounting, very high wattage ratings4. Semiconductor Resistors - High frequency/precision surface mount thin film technologyComposition ResistorsCarbon Resistors are the most common type of Composition Resistors as they are a cheap general purpose resistor. Their resistive element is manufactured from a mixture of finely ground carbon dust or graphite (similar to pencil lead) and a non-conducting ceramic (clay) powder to bind it all together. The ratio of carbon to ceramic determines the overall resistive value of the mixture and

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the higher this ratio is the lower the resistance. The mixture is then moulded into a cylindrical shape and metal wires or leads are attached to each end to provide the electrical connection before being coated with an outer insulating material and colour coded markings.Carbon Resistor

Carbon Composite Resistors are low to medium power resistors with low inductance which makes them ideal for high frequency applications but they can also suffer from noise and stability when hot. Carbon composite resistors are prefixed with a "CR" notation (eg CR10kΩ) and are available in E6 (±20% tolerance (accuracy)), E12 (±10% tolerance) and E24 (±5% & ±2% tolerance) packages with power ratings from 0.125 or 1/4 Watt up to 2 Watts.

Film ResistorsThe generic term "Film Resistor" consist of Metal Film, Carbon Film and Metal Oxide Film resistor types, which are generally made by depositing pure metals, such as nickel, or an oxide film, such as tin-oxide, onto an insulating ceramic rod or substrate. The resistive value of the resistor is controlled by increasing the desired thickness of the film and then by laser cutting a spiral helix groove type pattern into this film. This has the effect of increasing the conductive or resistive path, a bit like taking a long length of straight wire and forming it into a coil.This method of manufacture allows for much closer tolerance resistors (1% or less) as compared to the simpler carbon composition types. The tolerance of a resistor is the difference between the preferred value (i.e, 100 ohms) and its actual

41

manufactured value i.e, 103.6 ohms, and is expressed as a percentage, for example 5%, 10% etc, and in our example the actual tolerance is 3.6%. Film type resistors also achieve a much higher maximum ohmic value compared to other types and values in excess of 10MΩ (10 Million Ω´s) are available.

Film Resistor

Metal Film Resistors have much better temperature stability than their carbon equivalents, lower noise and are generally better for high frequency or radio frequency applications. Metal Oxide Resistors have better high surge current capability with a much higher temperature rating than the equivalent metal film resistors.Another type of film resistor commonly known as a Thick Film Resistor is manufactured by depositing a much thicker conductive paste of CERamic and METal, called Cermet, onto an alumina ceramic substrate. Cermet resistors have similar properties to metal film resistors and are generally used for making small surface mount chip type resistors, multi-resistor networks in one package for pcb's and high frequency resistors. They have good temperature stability, low noise, and good voltage ratings but low surge current properties.Metal Film Resistors are prefixed with a "MFR" notation (eg MFR100kΩ) and a CF for Carbon Film types. Metal film resistors are available in E24 (±5% & ±2% tolerances), E96 (±1% tolerance) and E192 (±0.5%, ±0.25% & ±0.1% tolerances) packages with power

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ratings of 0.05 (1/20th) of a Watt up to 1/2 Watt. Generally speaking Film resistors are precision low power components.Wirewound ResistorsAnother type of resistor, called a Wirewound Resistor, is made by winding a thin metal alloy wire (Nichrome) or similar wire onto an insulating ceramic former in the form of a spiral helix similar to the Film Resistors. These types of resistors are generally only available in very low ohmic high precision values (from 0.01 to 100kΩ) due to the gauge of the wire and number of turns possible on the former making them ideal for use in measuring circuits and Whetstone bridge type applications. They are also able to handle much higher electrical currents than other resistors of the same ohmic value with power ratings in excess of 300 Watts. These high power resistors are moulded or pressed into an aluminum heat sink body with fins attached to increase their overall surface area to promote heat loss. These types of resistors are called "Chassis Mounted Resistors". They are designed to be physically mounted onto heatsinks or metal plates to further dissipate the generated heat increasing their current carrying capabilities even further.Another type of wirewound resistor is the Power Wirewound Resistor. These are high temperature, high power non-inductive resistor types generally coated with a vitreos or glass epoxy enamel for use in resistance banks or DC motor/servo control and dynamic braking applications. The non-inductive resistance wire is wound around a ceramic or porcelain tube covered with mica to prevent the alloy wires from moving when hot. Wirewound resistors are available in a variety of resistance and power ratings with one main use of Power Wirewound Resistor is in the electrical heating elements of an electric fire which converts the electrical current flowing through it into heat with each element dissipating up to 1000 Watts, (1kW) of energy.

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Because the wire is wound into a coil, it acts like an inductor causing them to have inductance as well as resistance and this affects the way the resistor behaves in AC circuits by producing a phase shift at high frequencies especially in the larger size resistors. The length of the actual resistance path in the resistor and the leads contributes inductance in series with the "apparent" DC resistance resulting in an overall impedance path Z. impedance (Z) is the combined effect of resistance (R) and inductance (X), measured in ohms and for a series AC circuit is given as, Z2 = R2 + X2.When used in AC circuits this inductance value changes with frequency (inductive reactance, XL = 2πƒL) and therefore, the overall value of the resistor changes. Inductive reactance increases with frequency but is zero at DC (zero frequency). Then, wirewound resistors must not be designed into AC or amplifier type circuits where the frequency across the resistor changes. However, special non-inductive wirewound resistors are also available.Wirewound Resistor

Wirewound resistor types are prefixed with a "WH" or "W" notation (eg WH10Ω) and are available in the WH Aluminium Cladded package (±1%, ±2%, ±5% & ±10% tolerance) or the W Vitreous Enamelled package (±1%, ±2% & ±5% tolerance) with power ratings from 1W to 300W or more.

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4.2 Software, Simulation Tool UsedThe following software and simulation tool is used:

4.2.1 Proteus

The Proteus tool is used for simulation. After testing on the software, the physical

circuit was built. The testing of this circuit was performed on proteus for the accurate

and required results. This software is key testing software before making a practical

circuit on PCB or breadboard

4.2.2 Eagle

This software is used for designing printed circuit boards. Its interface allows quick

creation of own circuit boards. Core features of PCB wizard are schema drawing,

capturing schematic, auto routing, CAD/CAM support and such other features make it

a snap. After capturing the schematic components were connected on the PCB.

Chapter 5

CONCLUSION

Our project entitled Fabrication of solar powered grass cutter is successfully

completed and the results obtained are satisfactory. It will be easier for the people

who are going to take the project for the further modifications. This project is more

suitable for a common man as it is having much more advantages i.e, no fuel cost, no

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pollution and no fuel residue, less wear and tear because of less number of moving

components and this can be operated by using solar energy. This will give much more

physical exercise to the people and can be easily handled. As we are nearer to

Equator, the solar energy (non-conventional energy) is vastly available, so it is easy to

charge the battery and is also pollution free. But the initial investments of the solar

powered grass cutter is high. At present in order to curtail global warming and ozone

depletion. So in future it is expected to run all equipments by using solar energy. This

system is having facility of charging the batteries while the solar powered grass cutter

is in motion. So it is much more suitable for grass cutting also. The same thing can be

operated in night time also, as there is a facility to charge these batteries in day light.

FUTURE SCOPE

as we are using RF for wireless transmission, the range is quite limited; nearly 50-

80m. This problem can be solved by utilizing a GSM module for wireless

transmission. The GSM infrastructure is installed almost all over the world. GSM will

not only provide wireless connectivity but also quite a large range.The on-board

batteries occupy a lot of space and are also quite heavy. We can either use some

alternate power source for the batteries or replace the current DC Motors with ones

which require less power.

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REFRENCEShttps://www. arduino .cc/en/Main/ arduino BoardUno

https://learn.sparkfun.com/tutorials/what-is-an- arduino

www.instructables.com/id/Intro-to- Arduino /.../ Arduino -Uno-Features

https://en.wikipedia.org/wiki/Arduinohttps://en.wikipedia.org/wiki/ Resistor

https://en.wikipedia.org/wiki/ 2N2222

www.electroschematics.com/9598/ spdt - relay -switch/

http://www.slideshare.net/mahkamkhan/wireless-gesture-controlled-robot-fyp-report

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