how to make mini freezer at home -10 Deg / ICE Maker

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GREEN TECHNOLOGY BASED ARCHITECTURE DESIGN OF POWER SUPPLY SYSTEM FOR A METRO AREA

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In this work we will develop and suggest new control strategies for the fully coordinated and
synchronized  power  generation  on  a  distributed  power  grid  station  utilizing  different
renewable energy sources. The  strategies  are  based  on Digital  controller  and  can  easily
be  implemented on any  digital  device  such  as  FPGA, CPLD, and PC. It can be simulated
in  software  environment  like  E-TAP  and  MATLAB.  In  this  project  our  major  focus  is
replacing conventional power system into a modern smart grid technology.
Currently    we    are    going    to    suggest    the    practical    implementation    of    this
technology  in  The  Islamia  University  of  Bahawalpur but this project can be implemented
in  any  geographical  region  all  around  the  world.  In  this  system  we  are  going  to  explain  the
load  management  and  way  of  most  economical  smart  power  generation  and  consumption
system. We have elaborated the techniques to include the modern communication system and
used  the  artificial  intelligence  approach  for  the  betterment  of  electric  power  system.  Smart
Meters  technology  is  also  facilitated  due  to  its  vast  advantages  in  electricity  saving  by
visualizing the two way communication which is available to both customers and the service
providers.
   Our  suggested  model  will  be  providing  the  service  continuity  in  all  conditions.  Our
project  is  based  on  complete  hierarchy  of  the  general  power  system  from  generation
to  consumption  level.

Introduction to Smart Grid and its Major Elements

What are smart grids?

A  smart  grid  is  an  electricity  network  that  uses  digital  and  other  advanced  technologies  to 

monitor  and  manage  the  transport  of  electricity  from  all  generation  sources  to  meet  the 

varying electricity  demands of end-users. Smart  grids co-ordinate the needs and capabilities 

of all generators, grid operators, end-users  and  electricity market stakeholders to operate all 

parts  of  the  system  as  efficiently  as  possible,  minimizing  costs  and  environmental  impacts 

while  maximizing  system reliability, resilience and stability. 

For  the  purposes  of  this  roadmap,  smart  grids  include  electricity  networks 

(transmission  and  distribution  systems)  and  interfaces  with  generation,  storage  and  end-users.1  while  many  regions  have  already  begun  to  ―smarten‖  their  electricity  system,  all 

regions will require significant additional investment and planning to achieve a smarter grid. 

The world‘s electricity systems face a number of challenges, including ageing infrastructure, 

continued  growth  in  demand,  the  integration  of  increasing  numbers  of  variable  renewable 

energy sources and electric vehicles, the need to improve the security of supply and the need 

to  lower  carbon  emissions.  Smart  grid  technologies  offer  ways  not  just  to  meet  these 

challenges  but  also  to  develop  a  cleaner  energy  supply  that  is  more  energy  efficient,  more 

affordable and more sustainable. Following Figure demonstrates the evolutionary character of 

smart grids. 

Characteristics of smart grids: 

These  challenges  must  also  be addressed with regard to each region‘s unique technical,  financial  and  commercial  regulatory environment. Given the highly regulated nature of  the  electricity  system,  proponents  of  smart grids  must  ensure  that  they  engage  with  all stakeholders,  including  equipment 

manufacturers, system operators, and consume

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Inductors

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Inductors

Inductors.....

An inductor (also choke, coil or reactor) is a passive two-terminal electrical component that stores energy in its magnetic field. For comparison, a capacitor stores energy in an electric field, and a resistor does not store energy but rather dissipates energy as heat.
Any conductor has inductance. An inductor is typically made of a wire or other conductor wound into a coil, to increase the magnetic field.
When the current flowing through an inductor changes, creating a time-varying magnetic field inside the coil, a voltage is induced, according to Faraday's law of electromagnetic induction, which by Lenz's law opposes the change in current that created it. Inductors are one of the basic components used in electronics where current and voltage change with time, due to the ability of inductors to delay and reshape alternating currents.

Inductance (L) results from the magnetic field forming around a current-carrying conductor. Electric current through the conductor creates a magnetic flux proportional to the current. A change in this current creates a corresponding change in magnetic flux which, in turn, by Faraday's law generates an electromotive force (EMF) in the conductor that opposes this change in current. Thus inductors oppose changes in current through them. Inductance is a measure of the amount of EMF generated per unit change in current. For example, an inductor with an inductance of 1 henry produces an EMF of 1 volt when the current through the inductor changes at the rate of 1 ampere per second. The number of loops, the size of each loop, and the material it is wrapped around all affect the inductance. For example, the magnetic flux linking these turns can be increased by coiling the conductor around a material with a high permeability such as iron.

An inductor is usually constructed as a coil of conducting material, typically copper wire, wrapped around a core either of air or of ferromagnetic or ferromagnetic material. Core materials with a higher permeability than that of air increase the magnetic field and confine it closely to the inductor, thereby increasing the inductance. Low frequency inductors are constructed like transformers, with cores of electrical steel laminated to prevent eddy currents. 'Soft' ferrites are widely used for cores above audio frequencies, since they do not cause the large energy losses at high frequencies that ordinary iron alloys do. Inductors come in many shapes. Most are constructed as enamel coated wire (magnet wire) wrapped around a ferrite bobbin with wire exposed on the outside, while some enclose the wire completely in ferrite and are referred to as "shielded". Some inductors have an adjustable core, which enables changing of the inductance. Inductors used to block very high frequencies are sometimes made by stringing a ferrite cylinder or bead on a wire.
Small inductors can be etched directly onto a printed circuit board by laying out the trace in a spiral pattern. Some such planar inductors use a planar core.
Small value inductors can also be built on integrated circuits using the same processes that are used to make transistors. Aluminum interconnect is typically used, laid out in a spiral coil pattern. However, the small dimensions limit the inductance, and it is far more common to use a circuit called a "gyrator" that uses a capacitor and active components to behave similarly to an inductor.

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Full form of computer related terms:

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Full form of computer related terms:

* HTTP - Hyper Text Transfer Protocol.
* HTTPS - Hyper Text Transfer Protocol Secure.
* IP - Internet Protocol.
* URL - Uniform Resource Locator.
* USB - Universal Serial Bus.
* VIRUS - Vital Information Resource Under Seized.
* 3G - 3rd Generation.
* GSM - Global System for Mobile Communication.
* CDMA - Code Divison Multiple Access. 
* UMTS - Universal Mobile Telecommunication System.
* SIM - Subscriber Identity Module.
* AVI = Audio Video Interleave
* RTS = Real Time Streaming
* SIS = Symbian OS Installer File
* AMR = Adaptive Multi-Rate Codec
* JAD = Java Application Descriptor
* JAR = Java Archive
* JAD = Java Application Descriptor
* 3GPP = 3rd Generation Partnership Project
* 3GP = 3rd Generation Project
* MP3 = MPEG player 3 
* MP4 = MPEG-4 video file
* AAC = Advanced Audio Coding
* GIF = Graphic Interchangeable Format
* JPEG = Joint Photographic Expert Group
* BMP = Bitmap
* SWF = Shock Wave Flash
* WMV = Windows Media Video
* WMA = Windows Media Audio
* WAV = Waveform Audio
* PNG = Portable Network Graphics
* DOC = Document (Microsoft Corporation)
* PDF = Portable Document Format
* M3G = Mobile 3D Graphics 
* M4A = MPEG-4 Audio File
* NTH = Nokia Theme (series 40)
* THM = Themes (Sony Ericsson)
* MMF = Synthetic Music Mobile Application File
* NRT = Nokia Ringtone 
* XMF = Extensible Music File
* WBMP = Wireless Bitmap Image
* DVX = DivX Video
* HTML = Hyper Text Markup Language
* WML = Wireless Markup Language
* CD - Compact Disk.
* DVD - Digital Versatile Disk.
* CRT - Cathode Ray Tube.
* DAT - Digital Audio Tape.
* DOS - Disk Operating System.
* GUI - Graphical User Interface.
* HTTP - Hyper Text Transfer Protocol.
* IP - Internet Protocol.
* ISP - Internet Service Provider.
* TCP - Transmission Control Protocol.
* UPS - Uninterruptible Power Supply.
* HSDPA - High Speed Downlink Packet Access.
* EDGE - Enhanced Data Rate for GSM Evolution.
* GSM - Global System for Mobile Communication.
* VHF - Very High Frequency.
* UHF - Ultra High Frequency.
* GPRS - General Packet Radio Service.
* WAP - Wireless Application Protocol.
* TCP - Transmission Control Protocol.
* ARPANET - Advanced Research Project Agency Network.
* IBM - International Business Machines.
* HP - Hewlett Packard.
* AM/FM - Amplitude/ Frequency Modulation.
* WLAN - Wireless Local Area Network

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GSM MODULE IN PAKISTAN

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Brand New: 
Complete module containing SIM900D GSM module, with SIM jacket and antenna. ready for interfacing with your microcontroller. needs plain AT commands on serial interface to send and receive SMS data.
Also Antenna

• GSM SIM900  Module work on AT Commands.
• It supports RS-232 so you can connect it with any microcontroller (PIC , ATMEL, Arduino etc).
• You can also operate it with computer and can get data on hyper terminal or any other serial terminal.
• ANY GSM Sim is placed in its  sim  jacket  and it is  operated on 3.7V and further controller by the commands it is receiving.

• Price : Rs. 2500 in Pakistan.

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XBEE MODULE IN PAKISTAN

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This is the Pro (higher-power) version of the popular XBee! This module is series #1 (802.15.4 protocol) 60mW wireless module, good for point-to-point, multipoint and convertible to a mesh network point. These are much more powerful than the plain XBee modules, great for when you need more range. 

What we like about the Series 1 modules is that they are so easy to get set up. If you have two in range, they will automatically form a serial link with no configuration, so you can send TTL serial data back and forth. You can also configure the baudrate, as well as sleep modes, power modes and tons more stuff using the Digi XBee tool. 

The pins on an XBee are 2mm spacing, not 0.1" so they will not fit into a breadboard. For that reason, they work best in our XBee adapter module kit 
This module comes with a wire antenna 

XBee Pro Module - Series 01
Pak Rs 5600

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ZIGBEE MODULE IN PAKISTAN

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This is the very popular 2.4GHz XBee module from Digi. These modules take the 802.15.4 stack (the basis for Zigbee) and wrap it into a simple to use serial command set. These modules allow a very reliable and simple communication between microcontrollers, computers, systems, really anything with a serial port! Point to point and multi-point networks are supported.

• 3.3V @ 50mA
• 250kbps Max data rate
• 1mW output (+0dBm)
• 300ft (100m) range
• Wire antenna
• Fully FCC certified
• 6 10-bit ADC input pins
• 8 digital IO pins
• 128-bit encryption
• Local or over-air configuration
• AT or API command set

ZIGBEE MODULE IN PAKISTAN VERY CHEAP RATE 

XBee 1mW Wire Antenna - Series 1

Price per Unit (piece): PKR 3,100 

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Transistor in urdu

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ایک ٹرانجسٹر الیکٹرانک سگنل اور بجلی amplify اور سوئچ کرنے کے لئے استعمال کیا جاتا ہے ایک سیمی کنڈکٹر آلہ ہے. یہ ایک بیرونی سرکٹ پر کنکشن کے لئے کم از کم تین ٹرمینلز کے ساتھ سیمیکمڈکٹر مواد پر مشتمل ہے. ٹرانجسٹر کے ٹرمینلز میں سے ایک جوڑے پر لاگو ایک وولٹیج یا موجودہ ٹرمینلز کے ایک جوڑے کے ذریعے تازہ ترین تبدیلیاں. کنٹرول (کی پیداوار) بجلی کی کنٹرولنگ (ان پٹ) کی طاقت کے مقابلے میں زیادہ ہو سکتی ہے کیونکہ ایک ٹرانجسٹر ایک سگنل amplify کرسکتے ہیں. آج، کچھ ٹرانجسٹروں انفرادی طور پر پیک کر رہے ہیں، لیکن بہت زیادہ انٹیگریٹڈ سرکٹس میں سرایت پائے جاتے ہیں.

ٹرانجسٹر جدید الیکٹرانک آلات کے بنیادی عمارت بلاک ہے، اور جدید الیکٹرانک نظام میں ہر جگہ ہے. ابتدائی 1950s میں اس کی ترقی کے بعد ٹرانجسٹر الیکٹرانکس کے میدان میں انقلاب، اور دوسری چیزوں کے درمیان چھوٹے اور کم قیمت میں ریڈیو، calculators، اور کمپیوٹر کے لئے راہ ہموار کی.

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Different types of DIODES

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Different types of diodes

#Small signal or Small current diode

#Large signal diodes 

#Zener diodes

#Light emitting diodes (LED)

#Photodiodes

#Constant current diodes

#Schottky diode

#Shockley diode

#Step recovery diodes 

#Tunnel diodes

#Varactor diodes 

#PIN diodes

#LASER diode

#Transient voltage supression diodes 

#Gold doped diodes

#Super barrier diodes

#Point contact diodes

#Peltier diodes

#Gunn diode

#Crystal diode 

#Avalanche diode

#Silicon controlled rectifier 

#Vaccum diodes

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Stepper Motor Working

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Stepper Motors Working

Stepper motors contains of a permanent magnetic rotating shaft, called the rotor, and electromagnets on the stationary portion that surrounds the motor, called the stat-or Fig-01 illustrates one complete rotation of a stepper motor. At position 1, we can see that the rotor is beginning at the upper electromagnet, which is currently active (has voltage applied to it). To move the rotor clockwise (CW), the upper electromagnet is deactivated and the right electromagnet is activated, causing the rotor to move 90 degrees CW, aligning itself with the active magnet. This process is repeated in the same manner at the south and west electromagnets until we once again reach the starting position.

In the above example, we used a motor with a resolution of 90 degrees or demonstration purposes. In reality, this would not be a very practical motor for most applications. The average stepper motor's resolution -- the amount of degrees rotated per pulse -- is much higher than this. For example, a motor with a resolution of 5 degrees would move its rotor 5 degrees per step, thereby requiring 72 pulses (steps) to complete a full 360 degree rotation.

There are several types of stepper motors. 4-wire stepper motors contain only two electromagnets; however the operation is more complicated than those with three or four magnets, because the driving circuit must be able to reverse the current after each step. For our purposes, we will be using a 6-wire motor.

we  may double the resolution of some motors by a process known as "half-stepping". Instead of switching the next electromagnet in the rotation on one at a time, with half stepping you turn on both electromagnets, causing an equal attraction between, thereby doubling the resolution. As you can see in Fig-02, in the first position only the upper electromagnet is active, and the rotor is drawn completely to it. In position 2, both the top and right electromagnets are active, causing the rotor to position itself between the two active poles. Finally, in position 3, the top magnet is deactivated and the rotor is drawn all the way right. This process can then be repeated for the entire rotation.

Unlike our example motors which rotated 90 degrees per step, real-world motors employ a series of mini-poles on the stator and rotor to increase resolution. Although this may seem to add more complexity to the process of driving the motors, the operation is identical to the simple 90 degree motor we used in our example. An example of a multi-pole motor can be seen in Fig-03. In position 1, the north pole of the rotor's permanent magnet is aligned with the south pole of the stator's electromagnet. Note that multiple positions are aligned at once. In position 2, the upper electromagnet is deactivated and the next one to its immediate left is activated, causing the rotor to rotate a precise amount of degrees.

 In this example, after eight steps the sequence repeats.

The specific stepper motor we are using for our experiments (ST-02: 5VDC, 5 degrees per step) has 6 wires coming out of the casing. If we follow Fig-04, the electrical equivalent of the stepper motor, we can see that 3 wires go to each half of the coils, and that the coil windings are connected in pairs. This is true for all four-phase stepper motors.

However, if you do not have an equivalent diagram for the motor you want to use, you can make a resistance chart to decipher the mystery connections. There is a 13 ohm resistance between the center-tap wire and each end lead, and 26 ohms between the two end leads. Wires originating from separate coils are not connected, and therefore would not read on the ohm meter.

First Stepper Circuit

Fig-05 is the schematic of our first test circuit. The PIC's output lines are first buffered by a 4050 hex buffer chip, and are then connected to an NPN transistor. The transistor used, TIP120, is actually a NPN Darlington (it is shown as a standard NPN).

Due to a inductive surge created when a coil is toggled, a standard 1N4001 diode is usually placed across each transistor as shown in the figure, providing a safe way of dispersing the reverse current without damaging the transistor.

 The TIP120 transistors do not need an external snubbing diode because they have a built in diode. So the diodes shown in the drawing are the internal diodes in the TIP120 transistors.

The simplest way to operate a stepper motor with a PIC is with the full step pattern shown in Table 1. Each part of the sequence turns on only one transistor at a time, one after the other. After the sequence is completed, it repeats infinitely until power is removed.

Table 1

Q1	Q2	Q3	Q4
+	-	-	-
-	+	-	-
-	-	+	-
-	-	-	+

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FET IN URDU

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FET

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Hardware Implementation OF QUADCOPTER

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After successful implementation of various stages we reached the last and final stage it is//
hardware implementation. It is further divided in two categories.
1.  Mechanical work
2.  Electronic work

Mechanical work OF QUADCOPTER

After the airframe was designed and the components were purchased, we needed to place 

the  components  appropriately  on  the  airframe.  First  of  all,  the  circuit  board,  which 

consists of the microcontroller and other circuit elements, was placed on top at the center 

of  the  circular  cage  like  structure.  The  battery  pack  was  placed  underneath  the  circuit 

board  inside  the  circular  cage  like  structure.  Each  of  the  4  Electronic  Speed  Controllers 

(ESCs)  were  placed  on  each  of  the  arms  of  the  airframe,  with  their  inputs  commonly 

connected to the battery pack, and their 3 outputs are connected to the 3 input poles of the 

motor. Each of the four motors are placed at the ends of each of the arms, with their shaft 

directly inline with the center of the circular space designed for the circular motor mount. 

As for the propellers, the tractor propellers  were placed on the shafts  of  the motors that 

operated  in  the  clockwise  direction.  Similarly,  the  pusher  propellers  were  placed  on  the 

shafts of the motors that operated in the counterclockwise direction. Attention should be 

given to assembling of parts;  there should be no loose components as they  will  produce 

vibrations making quadrotor unstable. Some important points are given below in detail as 

they need special attention. After assembling of parts the figure of our quadrotor is shown 

below. 

Motor Alignment  OF QUUADCOPTER

The act of assembling the motor to the frame is extremely difficult due to the fact that the 

holes  needed  to  be  drilled  to  within  +/-  .1o

  of  each  other.  Any  successful  flying  device 

must be perfectly balanced, and this is very prevalent when dealing with a quad rotor. In 

order to achieve a balanced vertical flight, the group needed to be certain that the motors 

were  perfectly  straight.  If  the  motors  were  not  perfectly  aligned,  achieving  a  balanced, 

smooth flight would be nearly impossible. With this in mind, we devised a way to be sure 

that all the motor were aligned correctly. By setting the frame of the quad rotor on a flat 

surface, we used a T-square held against the motor. If the motors were directly against the 

edge of the square, then the motor would be aligned in a 90 degree angle.

Propeller Balancing 

Due  to  the  fact  that  the  propellers  are  operating  at  such  a  high  RPM,  it  is  crucial  to  the 

quad  rotors  performance  that  the  propellers  are  balanced.  Although  theoretically  the 

propellers are designed to have symmetric blades, in reality there are slight imperfections. 

These imperfections cause the propellers to vibrate uncontrollably, making smooth flight 

almost  impossible.  By  balancing  the  propellers,  vibrations  can  be  significantly  reduced.   

The  group balanced  the propellers by  examining  the relative weight distribution of each 

propeller. There are several types of commercially available propeller balancing devices, 

but  a  similarly  effective  device  was  made.  The  method  used  consisted  of  attaching  the 

propeller to a spindle held up between two blocks, allowing the propellers to rotate freely. 

If  one  of  the  blades  is  heavier  than  the  other,  then  the  propeller  will  rotate  towards  the 

heavier blade. In such a case, the blades trailing edge was sanded down to compensate for 

the  mass  difference.  Once  the  blades  weights  were  evenly  distributed,  the  propeller 

balanced horizontally.  

Quad Rotor Balancing 

The  quad  rotor,  which  includes  air  frame,  dc  motor,  electronic  speed  controller, 

propellers,  batteries  and  electronic  circuits,  was  carefully  designed  and  assembled  with 

the  idea  of  having  a  helicopter  which  is  as  close  to  perfect  in  terms  of  its  weight 

distribution  throughout  the  entire  aircraft.  Achieving  a  steady  and  controllable  flight  is 

almost  impossible  to  achieve  unless  the  aircraft  is  as  close  to  perfect  balance.    The 

addition of the electronic components and battery onto the frame of the quad rotor leaves 

its  weight  distribution  inconsistent  throughout.  As  a  result,  we  devised  a  way  to  make 

sure that the frame is as balanced as possible.  

The way to do this is by attaching a piece of string to the center of the hub and allowing 

the quad rotor to float freely. If the weight is not evenly distributed, then the quad rotor 

will lean towards the heaviest part. The battery packs, which are mounted in the centre of 

air frame in cage like structure, were then adjusted to ensure the quadrotor was balanced 

in the x and y axes. 

 Electronics work OF QUADCOPTER

After describing the parts used in the construction of the quadrotor and their assembling, 

it is important to mention how the electronic components are made to work. This section 

describes  the  electronic  circuit;  a  block  diagram  of  the  electronic  design  is  shown  in 

Figure  below. 

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Quadcopter project

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The  helicopter  is  one  of  the  most  complex  flying  machines  due  to  its  versatility  and
maneuverability  to  perform  many  types  of  tasks.  Classical  helicopters  are  usually
equipped with a main rotor and a tail rotor. However, other types exist which use a twin
rotor.  Our  specific  project  is  concerned  with  the  design  and  control  of  a  miniature
rotorcraft, known as a quad-rotor helicopter [1]
. Quad  rotors  are  symmetrical  vehicles  with  four  equally  sized  rotors  at  the  end  of  four
equal  length  rods.  Unlike  their  counter  parts,  quad  rotors  make  use  of  multiple  rotors
allowing  for  a  greater  amount  of  thrust  and  consequently  a  greater  amount  of
maneuverability.
Fixed-wing  vehicles  have  long-range  since  they  are  energy  efficient,  but  they  lack  the
maneuverability required for many UAV tasks. For example, Blimps are easy to control
when there are fewer disturbances like wind, and lift comes from  natural  buoyancy, but
their  maneuverability  is  limited.  The  helicopters  have  advantages  over  conventional
fixed-wing aircraft and blimps on surveillance and inspection tasks, since they can take-off  and  land  in  limited  space  and  can  easily  hover  above  targets.  Moreover,  helicopters
have the  advantage of  maneuverability. Unfortunately, this  advantage makes helicopters
very hard to control, requiring sophisticated sensors and fast on-board computation [2]
.
Unmanned  aerial  vehicles  are  aircrafts  capable  of  flight  without  an  on-board  operator.
Such vehicles can be controlled remotely by an operator on the ground, or autonomously
via  a  pre-programmed  flight  path.    Today,  unmanned  aerial  vehicles  (UAVs)  are  an
important  part  of  scientific  study  both  in  military  and  space  studies.  As  a  substitute  for
human piloted vehicles they are advantageous to protect human life in multiple dangerous
environments.  Their  reliabilities  in  tough  circumstances  are  much  higher  than  their
counter parts.
UAVs  can  be  classified  into  two  major  groups:  heavier-than-air  and  lighter-than-air.
These  two  groups  self  divide  in  many  other  that  classify  aircrafts  according  to
motorization,  type  of  liftoff  and  many  other  parameters.  Vertical  Take-Off  and  Landing
(VTOL) UAVs like quadrotors have several advantages over fixed-wing airplanes. They
can move in any direction and are capable of hovering and fly at low speeds. In addition,
the  VTOL  capability  allows  deployment  in  almost  any  terrain  while  fixed-wing  aircraft
require a prepared airstrip for takeoff and landing. Given these characteristics, quadrotors
can  be  used  in  search  and  rescue  missions,  meteorology,  penetration  of  hazardous
environments (e.g. exploration of other planets) and other applications suited for such an
aircraft.  Also,  they  are  playing  an  important  role  in  research  areas  like  control
engineering, where they serve as prototypes for real life applications.
The design of unmanned aerial vehicles involves the integration of various steps such as
design,  selection  of  sensors  and  developing  controllers.  These  steps  can  not  be  treated
separately.  For  example,  one  can  not  design  a  vehicle  without  considering  the  sensory
input or the controllers that will be implemented, as these steps are closely related to each
other  [2]
.  Stabilizing  and  guidance  of  these  hovering  platforms  are  common  and  basic
tasks that have to be accomplished before assigning a mission to the vehicle.

Because of the ambitious nature of project goals, development of the UAV can be easily 
divided into five major stages:  


•  Vehicle conceptual design  
•  Analysis and component-level design and selection  
•  Fabrication, assembly, hardware testing, and re-design  
•  Simulation development and verification  
•  Control and estimation development for future implementation 

Though  these  five  stages  occasionally  overlapped  and  sometimes  interfered  with  one
another, they can be discussed independently.
Among  the specific significant engineering challenges  that  researchers are focusing on
for  the  development  of  successful  UAV  are: it should be  ultra-compact, lightweight,
high-power    and    high-energy-density    propulsion    and    power    sources;  untraditional
concepts    for    lift    generation;    flight    stabilization    and    control    for  aerodynamic
environments    with    very    low    Reynolds    numbers;    secure,    low-power  onboard
electronic    processing    and    communications    with    sufficient    bandwidth    for  real-time
imaging;    micro-gyroscopes    and    inertial    measurement    units    (IMU)    and  very    small
onboard  guidance,  navigation,  and  geo-location  systems.  To be really useful, a UAV
needs  to  carry  a  short-range  day/night  area  imaging  system  with  a  sufficient  resolution.
The  system  must  feature  an  accurate  geo-location  capability.  A  sufficient  vehicle  range
and real-time communications are also desired.
With  the  advent  of  new  technologies  ranging  from  global  positioning  systems  to  faster,
smaller,  and  lighter  computer  processors,  there  has  been  a  surge  in  development  of
unmanned  vehicles.    Unmanned  and  autonomous  vehicles  are  currently  in  development
for use in air, over land, and in the water by both private and government agencies.

Definition and Basic Concepts OF QUADCOPTER

A  quadrotor,  or  quadrotor  helicopter,  is  an  aircraft  that  becomes  airborne  due  to  the  lift
force provided by four rotors usually mounted in cross configuration, hence its name. It is
an  entirely  different  vehicle  when  compared  with  a  helicopter,  mainly  due  to  the  way
both  are  controlled.  Helicopters  are  able  to  change  the  angle  of  attack  of  its  blades,
quadrotors cannot.
The  first  question  one  is  asked  about  the  quadrotor  is  how  it  stands  out  from  the
traditional one. Hence a short introduction about the quadrotor construction and steering
principle  is  necessary.  The  quadrotor  is  a  mechatronic  system  with  four  rotors  that
provide the lift and control. With respect to hover, the main difference is best explained
by  considering  how  the  helicopters  compensate  from  gyroscopic  torques.  Traditional
helicopters basically compensate from the torque generated by the main rotor through the
tail rotor. However the tail rotor compensation conducts a sideways displacement of the
helicopter, thus counter steering by tilting the main rotor blades is necessary. In this way
hover  is  an  ongoing  and  complex  process.  The  quadrotor  has  four  propellers  driven  by
four motors in a cross configuration which are fixed to a certain spin axis. The spinning
directions  of  the  rotors  are  set  in  pairs  to  balance  the  torques,  therefore  eliminating  the
need for a tail rotor. While the front and the rear motor rotate counter-clockwise, the left
and  the  right  motor  rotate  clockwise,  as  long  as  the  rotors  rotate  at  the  same  speed  the
gyroscopic  effects  are  nearly  eliminated  and  the  quad  rotor  essentially  hovers,  this
proving  to  be  a  less  complex  maneuver  to  retain.  With  regard  to  application  and
functionality  the  quad  rotor  helicopter  has  the  same  immediate  advantages  as  the
traditional  helicopter.  One  additional  advantage  of  the  quad  rotor  compared  to  a
traditional  helicopter  is  the  simplified  rotor  mechanics.    By  varying  the  speed  of  the
single  motors,  the  lift  force  can  be  changed  and  vertical  and/or  lateral  motion  can  be
created.  However  a  number  of  issues  especially  regarding  the  mechanical  construction
prove  to  be  interesting  from  a  control  perspective  point  of  view.  The  first  and  foremost
issue  concerns  the  modeling  of  the  quad  rotor  as  this  proves  to  be  a  different  and  more
feasible task.

Quad Rotor Operation

Quadrotor is an under-actuated, dynamic vehicle with four input forces and six degrees of 

freedom.  Unlike  regular  helicopters  that  have  variable  pitch  angle  rotors,  a  quadrotor 

helicopter  has  four  fixed-pitch  angle  rotors.  The  quadrotor  is  very  well  modeled  with  a 

four rotors in a cross configuration. This cross structure is quite thin and light, however it 

shows  robustness  by  linking  mechanically  the  motors  (which  are  heavier  than  the 

structure).  Each  propeller  is  connected  to  the  motor  through  the  electronic  speed 

controller. All the propellers axes of rotation are fixed and parallel. Furthermore, their air 

flow  points  downwards  (to  get  an  upward  lift).  These  considerations  point  out  that  the 

structure is quite rigid and the only things that can vary are the propeller speeds. 

Each rotor in a quad rotor is responsible for a certain amount of thrust and torque about
its  center of  rotation, as  well as  for  a  drag force  opposite  to  the rotorcraft’s  direction of
flight.  These  props  would  provide  the  thrust  necessary  to  counter  gravity  while  also
providing sufficient residual thrust for control of roll and pitch (and subsequently forward
and lateral velocity),  yaw, and vertical velocity.   The basic  motions of a  Quad rotor are
generated by varying the rotor speeds of all four rotors, thereby changing the lift forces.
The  helicopter  tilts  towards  the  direction  of  the  slow  spinning  rotor,  which  enables
acceleration  along  that  direction.  Therefore,  control  of  the  tilt  angles  and  the  motion  of
the helicopter are closely related and estimation of orientation (roll and pitch) is critical.
As spinning directions of the rotors are set to balance the moments. This principle is used
to  produce  the  desired  yaw  motions.  In  order  to  define  an  aircraft’s  orientation  (or
attitude)  around  its  center  of  mass,  aerospace  engineers  usually  define  three  dynamic
parameters, the angles of yaw, pitch and roll. This is very useful because the forces used
to control the  aircraft act around its center of mass, causing it  to  pitch, roll or  yaw. The
generalized coordinates for a rotorcraft are:
q=(x, y, z, θ, φ, ψ)                (1.1)
Where (x, y, z) denote the position of the center of mass of the rotorcraft relative to the
frame, and (θ, φ, ψ) are the three Euler angles which represent the orientation of the craft
[3]
. Figure  shows the yaw, pitch and roll rotations of a quadrotor.


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Inside USB

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Inside USB.

1) USB Standard, Male A-plug
2) USB mass storage controller device
3) Test points
4) Flash memory chip
5) Crystal oscillator
6) LED (Optional)
7) Write-protect switch (Optional)
8) Space for second flash memory chip\

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Micro-Controller

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Introduction to PIC Micro controller
Features of PIC16F877: 
Peripheral Features:
Analog Features :
Pin Description of PIC16F877A :
Advantages of PIC :

Check for more information http://www.studenttraininglab.com

Introduction to PIC Micro controller

Micro-controller’s gives solutions to the whole performance range of 8-bit, 16-bit and 32-bit micro-controllers, with a powerful architecture, re-programming with flash memory and extensive easy-to-utilize development tools. There are many types of micro-controllers like 8051, AVR, PIC. In this article we are going to discuss about the PIC micro-controller. Let’s see:

There are many PICs, started with PIC16F84 and PIC16C84. But these were the only affordable flash PICs. Microchip has recently introduced flash chips with types that are much more attractive, such as 16F628, 16F877 and 18F452. The 16F877 is around twice the price of the old 16F84, but has eight times the code size, much more RAM, much more I/O pins, a UART, A/D converter and a lot more.

PIC is a peripheral interface controller, developed by general instrument’s microelectronics, in the year of 1993. It is controlled by the software. They could be programmed to complete many task and control a generation line and many more. PIC microcontrollers are finding their way into new applications like smart phones, audio accessories, video gaming peripherals and advanced medical devices.

Features of PIC16F877:

Core Features:

·         High-performance RISC CPU

·         Up to 8K x 14 words of FLASH program memory

·         35 Instructions (fixed length encoding-14-bit)

·         368×8 static RAM based data memory

·         Up to 256 x 8 bytes of EEPROM data memory

·         Interrupt capability (up to 14 sources)

·         Three addressing modes (direct, indirect, relative)

·         Power-on reset (POR)

·         Harvard architecture memory

·         Power saving SLEEP mode

·         Wide operating voltage range: 2.0V to 5.5V

·         High sink / source current: 25mA

·         Accumulator based machine

Peripheral Features:

·         3 Timer/counters (programmable pre-scalars)

o    Timer0, Timer2 are 8-bit timer/counter with 8-bit pre-scalar

o    Timer1 is 16-bit, can be incremented during sleep via external crystal/clock

·         Two capture, compare, PWM modules

o    Input capture function records the Timer1 count on a pin transition

o    A PWM function output is a square wave with a programmable period   and duty cycle.

·         10-bit 8 channel analog-to-digital converter

·         USART with 9-bit address detection

·         Synchronous serial port with master mode and I2C Master/Slave

·         8-bit parallel slave port

Analog Features:

·         10-bit, up to 8-channel Analog-to-Digital Converter (A/D)

·         Brown-out Reset (BOR)

·         Analog Comparator module (Programmable input multiplexing from device inputs and comparator outputs are externally accessible)

Pin Description of PIC16F877A:

PIC16F877A microcontroller is a 40-pin device and is one of the popular microcontrollers used in complex applications.

Advantages of PIC:

·         It is a RISC design

·         Its code is extremely efficient, allowing the PIC to run with typically less program memory than its larger competitors

·         It is low cost, high clock speed

A typical application circuit of PIC16F877A:

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