Auto Blimp Report

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SREE NARAYANA GURUKULAM COLLEGE OF ENGINEERING

KADAYIRIPPU, KOLENCHERY 682 311

AUTONOMOUS BLIMP

MINI PROJECT REPORT

DEPARTMENT OF ELECTRONICS & COMMUNICATIONS ENGG

SNG COLLEGE OF ENGINEERING

KOLENCHERY

2010


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AUTONOMOUS BLIMP

MINI PROJECT REPORT

Submitted By:

ARUN PATHAPPILLY SAJEEVAN

ARYA GEORGE

ANUSHA S

In the partial fulfillment for the award of the degree

BACHELOR OF TECHNOLOGY

in

ELECTRONICS AND COMMUNICATION ENGINEERING

SREE NARAYANA GURUKULAM COLLEGE OF ENGINEERING

KADAYIRIPPU, KOLENCHERY 682 311

MAHATMA GANDHI UNIVERSITY

KOTTAYAM 686 560

2010


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SREE NARAYANA GURUKULAM

COLLEGE OF ENGINEERING

(Affiliated to Mahatma Gandhi University & Approved by A.I.C.T.E)

KADAYIRUPPU, KOLENCHERY

DEPARTMENT OF ELECTRONICS AND COMMUNICATION

MINI-PROJECT REPORT 2010

CERTIFICATE

This is to certify that this project report entitled AUTONOMOUS

BLIMP is a report of the mini project of the mini project work done

by

..during the year 2010

Kadyiruppu

Date: Staff in Charge

Head of Department

Internal Examiner External Examiner


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Under The Guidance

of

Mr.Jobins George

Mr.Assini A.H

Mr.Noble.C.Kurian


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AKNOWLEDGEMENT

Success is a relative term. And my success in this small endeavor onto the

world of electronics demands the credit of many.

First of all to you God, for showering upon me the wisdom and keeping the path

clear towards the success of this project.

My whole hearted gratitude to my project guides Mr. Jobins George,

Mr.Assini.A.H and Mr.Noble C Kurian who worked along with me day and

night to keep my blimp in flight.

Our HOD Prof(Dr).Ramkumar SN has been one of the most impeccablepersonalities who has backed me with this project, I thank him for his invaluable

support.

My sincere thanks to my friends Supratik Mukherjee ( Texas A&M

University) Mudassir Rayani (Toronto University), Janus Lobo (Cornell

University) for their whole-hearted support throughout the project.

A special word of thanks to Mr.Leo C George and all my other senior

colleagues for their valuable advises.

I would like to thank each and every member of the Electronics and

Communication department at SNGCE for their constant encouragement and

valuable suggestions towards this project.

Lastly but never the least, to my friends and my parents; they have kept me and

my blimp flying, into successes.

Arun Pathappilly Sajeevan


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Abstract

This report describes the design of an autonomous

blimp based robot and its navigation system. Our project

controls a propeller-driven hydrogen blimp; it keeps the

blimp moving in a straight line if its path is clear, and

otherwise navigates it around obstacles in its path. To

accomplish the former task, our circuit uses a gyroscope

to detect horizontal rotation and compensates for it by

adjusting the propeller speed. Obstacle detection isperformed using an ultrasonic transmitter receiver pair.


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Rationale and Source of Ideas

Our motivation for choosing this project stems for our shared

assion for aviation. We agreed at the outset that we wanted an

airborne project. Using the microcontroller for some form ofautonomous control suggested itself naturally. Furthermore,

accomplishing this would require the analog-digital converter (ADC),

ulse-width modulation (PWM), as well as sensors and motors, and

therefore incorporate elements from throughout the duration of the

course. We also had a strong desire, however, to accomplish this

roject with everything onboard, and to have our blimp fly

independently of tether cables to supply power, since to the best of our

knowledge, no mini project has previously attempted an airborne

roject.


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CONTENTS

Introduction..........................................................................................................10

BLOCK DIAGRAM............................................................................................12

BLOCK DIAGRAM DESCRIPTION.................................................................13

CIRCUIT DIAGRAM .........................................................................................18

CIRCUIT DIAGRAM DESCRIPTION ..............................................................19

PROGRAM DESIGN..........................................................................................21

PROGRAM CODE..............................................................................................24

PCB DESIGN ......................................................................................................31PCB LAYOUT.....................................................................................................40

COMPONENT SIDE LAYOUT .........................................................................41

RESULTS............................................................................................................43

CONCLUSION....................................................................................................45

Bibliography ........................................................................................................52


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INTRODUCTION

CHAPTER 1


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Introduction

Non-rigid airships, also known as blimps, are basically unmanned aerial vehicles

(UAVs) that use gas (usually helium or hydrogen) balloons. In contrast to a rigid

airship, a blimp has no internal structure to maintain the shape of its hull envelope.

Rather, its shape is maintained by a higher pressure of the gas. The only rigidcomponents are the driving elements, the fins and the gondola attached to the

envelope. Unmanned blimp robots can be used in both indoor and outdoor

environments. The buoyancy force provides an energy-free form of lift, offering a

non-traditional approach to long-duration missions for which conventional aircrafts

are not well-suited. Miniaturization of sensors and actuators and the development

of long-duration batteries have also opened up opportunities for further progress in

the development of these small-scale autonomous vehicles.

The first rigid airships, which were constructed in the early 20th century,

consisted of a balloon with a metal frame covered by fabric and filled with a gas

(helium or hydrogen). These airships were mainly used in wars for military aerial

exploration and transportation. Nowadays, however, they are mainly used for

advertising and aerial filming. Nevertheless, they have great potential in terms of

applications such as search and rescue missions, traffic monitoring, urban

planning, inspection of power lines and pipelines, mineral and archaeological site

prospection, law enforcement and telecommunication relay systems. Blimps are

well-suited for these applications because their ability to remain stationary for longperiods of time in the air enables data to be gathered. Blimps can also be used for

research purposes in a variety of applications including ecological, biodiversity and

climate research and monitoring in different environments.

Our primary interest was the development of a low-cost blimp designed to

operate autonomously in indoor environments where different control strategies

and navigation paradigms are tested and evaluated. The design of a blimp imposes

certain restrictions, primarily because of its limited payload capability, given that a

blimp relies on its neutral buoyancy to stay afloat. A key challenge was to build an

electronic board that was sufficiently light to be carried on board the blimp.

Electronic components were selected to fit our main navigation requirements

including limited autonomous navigation capabilities.


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BLOCK DIAGRAM

CHAPTER 2


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BLOCK DIAGRAM

PIC 16F873A

GYROSCOPE

ULTRASONIC

PROXIMITY SENSOR

MICRO MOTOR

CIRCUITS


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BLOCK DIAGRAM DESCRIPTION

Background Math

The volume of the blimp is 5ft3, or about 0.141m3. The lifting power of 1ft3

of hydrogen gas is about .076 pounds at 0 degree Celsius, and hence our blimp hadan estimated payload of about 172g. As it turned out the actual maximum payload

was about 120-150g, depending on the temperature and how recently the blimp hadbeen refilled.

The motors each draw up to 150mA at full duty cycle for a total of 300mA.

The MCU draws about 40mA, while the ultrasonic transmitter receiver pair and

gyroscope together draw about 30mA, putting our total typical current load (at86% duty cycle) at about 350mA.

Our largest tradeoffs were to accommodate the constraint of lift. We hadinitially proposed to mount sensors on the sides and base of the blimp as well, but

these would have put the total weight of all components well above the payload ofthe blimp. Long wires running along the exterior of the blimp would also haveadded significantly to the weight.

HARDWARE DESIGN

Microcontroller Unit

We used a PIC 16F873A for navigating the hydrogen blimp autonomously. Aswe were in need of an ADC unit, PWM modules and overall a simple but a

lightweight MCU, PIC 16F873A was the obvious choice because of its followingproperties:

High performance RISC CPU

Only 35 single word instructions to learn. Two Capture, Compare, PWM modules.


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PIN DIAGRAM of PIC16F873A

10-bit multi-channel Analog-to-Digital converter. Low-power consumption:

- < 0.6 mA typical @ 3V, 4 MHz

- 20 A typical @ 3V, 32 kHz

- < 1 A typical standby current


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SENSORS:

1. GYROSCOPE

We used an X-Y axis gyroscope, LISY 300 AL The gyroscope was

read using the ADC and we measured only rotation around the vertical axisi.e. turning left or right. We filtered the output of the gyroscope using a

hardware low pass filter with a cutoff frequency of 1 kHz, the recommendedvalue to eliminate noise from the MEMS component in the gyroscope.

The LISY300AL is a low-power single-axis yaw rate sensor. It

includes a sensing element and an IC interface able to provide the measuredangular rate to the external world through an analog output voltage. The

sensing element, capable of detecting the yaw rate, is manufactured using adedicated micromachining process developed by ST to produce inertial

sensors and actuators on silicon wafers. The IC interface is manufacturedusing a CMOS process that allows a high level of integration to design a

dedicated circuit which is trimmed to better match the sensing elementcharacteristics.

The LISY300AL has a full scale of 300 /s and is capable of

measuring rates with a -3 dB bandwidth up to 88 Hz. The LISY300AL is

available in a plastic land grid array (LGA) package and can operate within atemperature range from -40 C to +85 C.

Its features are:

2.7 V to 3.6 V single supply operation

Low power consumption

Embedded power-down

300 /s full scale

Absolute analog rate output

Integrated low-pass filters

Embedded self-test

High shock survivability


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2. ULTRASONIC PRO

An ultrasonic t

to detect obstacles. Twaves are transmittedthe receiver section. Iit does not detect an o

Ultrasonic

IMTY SENSOR

ansmitter receiver pair was used as a pro

e sensor has a specified range of up to 1from the transmitter side hit the obstacls output is digital and active low: it out

bject and 0 when it does.

Proximity Sensor Operation

Proximity Sensor LISY 300AL Gyroscop

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ximity sensor

. Ultrasonicand return touts VCC when

e


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CIRCUIT DIAGRAM

CHAPTER 3


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CIRCUIT DIAGRAM


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CIRCUIT DIAGRAM DESCRIPTION

POWER SUPPLY

The circuit is powered by regulated 5V. A 7.6 V Li-Po battery pack is used

as the main power source. As these battery packs have good power back up and

is light in weight, they were the best option for an aerial robotics circuitry.

MOTOR CIRCUITS

An opto-isolator circuit has been used for controlling the motor circuits. A

PWM input is given to the motors from the MCU and these in turn control the ON

OFF period of motor. The BUZ73 transistors have a turn-on voltage of 3.4V,

higher than the 3V we had initially planned to run the motors at. We replaced

these with N3904 BJTs, which have a much lower turn-on voltage and are also

slightly lighter.

The motors each draw up to 150mA at full duty cycle for a total of

300mA. The motors used were special high rpm micro motors used to drive toy

helicopter blades.

POWER CONSUMPTION

The MCU draws about 40mA, while the IR and gyroscope together draw about30mA, putting our total typical current load (at 86% duty cycle) at about 350mA.


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PROGRAM DESIGN

CHAPTER 4


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PROGRAM DESIGN

ADC

The ADC was used to read the filtered output of the gyroscope. The zero-rate

output (ZRO) of the gyroscope with VCC at 3V was 1.57V and corresponds to a 10-

bit ADC value of 535. We read and added ten values to effectively take the

average of ten readings for our comparisons with the ZRO value. The relevant

bypass capacitors were mounted on the custom PCB in the specified locations.

PWM

We used the two PWM signals from Timer 1 to control the speed of the

micromotors via the optoisolator circuits by increasing or decreasing the duty cycle

as appropriate. The signals had a frequency of 60Hz and the default duty cycle

was set at 86% (OCR=220).

Navigation Algorithm

When the proximity sensor does not detect an obstacle in its path, the MCU

turns the fans with the appropriate duty cycle to drive the blimp in a straight line.We implement a binary feedback mechanism whereby the MCU reads the

gyroscope and adjusts the PWM signals to compensate for any yaw. For instance,

if the ADC value from the gyroscope indicates that the blimp is veering left, the

MCU increases the PWM duty cycle to the left motor by 1bit and decreases the

PWM duty cycle to the right motor by 1bit, checking first not to exceed the bounds

of [0,255].

When an obstacle is detected, the blimp continues to move for 3 seconds and

then the motors stop turning the propellers by setting both duty cycles to 0. The 3

second wait allows the blimp to get a little closer to the obstacle, to ensure that the

latter does not disappear from view once the blimp begins to rotate away. The

MCU then increases the duty cycle of the left motor by 5 bits at each interrupt,

which causes the blimp to turn off to the right, and to continue to do so while the

obstacle is in view. Once the obstacle disappears from view, the blimp resumes


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forward motion at the default PWM duty cycle. We realize that multiple sensors

would have afforded a more complex navigation algorithm; we presented the

skeleton of one such algorithm in our project proposal.

We considered storing 100 gyroscope ADC readings in array and filtering themto remove both high frequency noise resulting from the motor vibration as well as

any possible low frequency drift, but neither of these was found to be sufficiently

problematic since the gyroscope is mounted at the nose of the blimp far away from

the motors, and we did not observe any perceivable drift over the duration of each

blimp 'ride'. Furthermore, it was not necessary to know with accuracy the actual

values of the ADC output. It was sufficient to know if the blimp was veering left

or right, and then simply increase and decrease the duty cycle of the appropriate

propellers slightly to compensate. We read the gyroscope and corrected the motors

at 0.5s intervals, and therefore corrections were made sufficiently frequently that

compared to the time delay of the movement of the blimp, our circuit would for all

practical purposes be responding continuously.


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PROGRAM CODE

CHAPTER 5


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PROGRAM CODE

/*Program for the autonomous blimp project*done by Arun Pathappilly Sajeevan under the*guidance of Assini AH */

#include#include#include#include

#define gyro PINA.0#define UD PINB.0#define Lprop PORT D.4#define numGrdgs 10 //number of gyroscope readings to be

averaged#define defaultThrust 128

unsigned char Ldrift, Rdrift, yawDetect, aamt;unsigned int i, gyroAccum;unsigned int Ain, adcl, adch;unsigned int timeBase500ms;

unsigned char obs, state, tt;unsigned char testInc;

void initialize(void);void readGyro (void);//void calcYaw(void)void nudgeL(void);void nudgeR(void);void detectObs(void);void blimpSM(void);

interrupt [TIM2_COMP] void timer2_compare(void) //occursevery 1msbegin

if (timeBase500ms>0) --timeBase500ms;

end


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void main(void){

initialize();while(1)

{ //state machine stuff

if (timeBase500ms==0){

blimpSM();}

}}

void initialize(void){

//IO PortsDDRB=0b00001000; //PORTB.3 for PWM output//B.1 fwd motorL ctrl, B.2 backward motorL ctrl, B.4 fwd

motorR, B.5 backward motorR

DDRD=0b00110000; //PORTD.4 and 5 for PWM output (OC1B andOC1A)

// IR sensor input into PORTDB.0

//init the A to D converter//channel zero/ left adj /EXTERNAL Aref

//!!!CONNECT Aref jumper!!!!ADMUX = 0b00000000; //reads A0//enable ADC and set prescaler to 1/128*16MHz=125,000//and clear interupt enable//and start a conversionADCSR = 0b11000111; //get the first conversion done

with coz longer//channel A0 for gyro//channel A1 for accelerometer?

tt=12;

//Timer stuffTIMSK = 0b10000000; //turn on timer 2 cmp match isr


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//Timer0 - used for PWM//fast PWM mode, full clock rate, toggle oc0 (pin B3)

//16 microsec per PWM cycle implies max freq for 16samples of

// 1/(16e-6*16) = 3900 Hz.

TCCR0 = 0b01101101;OCR0 = 240; //50% duty cycle

//Timer1 - used for PWMTCCR1A = 0b11110001; //clear on COMP, fast PWMTCCR1B = 0b00001101; //fast PWM, no prescalerOCR1AL = defaultThrust; //50% duty cycle, controls left

motorOCR1BL = defaultThrust; //50% duty cycle, controls right

motor

//Timer2 for timingOCR2 = 249; //set the compare re to 250 time ticksTCCR2 = 0b00001100; // prescaler to 64 and turn on clear on

match...1ms clk

//DDRC=0xff; //set to output, test using LEDs//PORTC=0x00;DDRC = 0xff; //set to input, buttons

/*setFwdMotorL();

setFwdMotorR();*/

//crank up ISRs#asm

sei#endasm

}

void readGyro(void){

gyroAccum = 0;

for(i=0;i


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adch = ADCH;Ain = adcl + (adch


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}

void turnRight(unsigned char amt){

for(i=0;i


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stop(); //props stop spinningstate=3;

}break;

case 3: //obstacle detected//PORTC=0x08;if(obs==1) {

turnRight(5);//turnRight(10);

}else if(obs==0) {

forward();state=1;

}break;

} //end switch

}


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PCB FABRICATION

CHAPTER 6


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PCB DESIGN


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PRINTED CIRCUIT BOARD

Printed Circuit Board (PCB) is a piece of art. The performance of an

electronic circuit depends on the layout and design of PCB. A PCB

mechanically supports and connects components by conductive pathways,

etched from copper sheets laminated on to insulated substrate. PCB, are used to

rotate electrical currents and signals through copper tracts which are firmly

bonded to an insulating base.

PCB Fabrication involves the following steps:

1. Drawing the layout of the PCB in a paper. The track layout of the Electronic

circuit should be made in such manner that the paths are in easy routes. It is then

transferred to a Mylar sheet. The sheet is then touched with black ink.

2. The solder side of the Mylar sheet is placed on the shiny side of the five-

Star sheet and is placed in a frame. Then it is exposed to sunlight with Mylar

sheet facing the sunlight.

3. The exposed five-star sheet is put in Hydrogen Peroxide solution. Then it is

put in hot water and shook till unexposed region becomes transparent.

4. This is put in cold water and then the rough side is stuck on to the silk

screen. This is then pressed and dried well.

5. The plastic sheet of the five-star sheet is removed leaving the pattern on the

screen.


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6. A copper clad sheet is cut to the size and cleaned. This is placed under

screen.

7. As it resistant ink if spread on the screen so that a pattern of tracks and a pad

is obtained on a copper clad sheet. It is then dried.

8. The dried sheet is then etched using Ferric Chloride solution (32Baume) till

all the unwanted Copper is etched away. Swish the board to keep the each fluid

moving. Lift up the PCB and check whether all the unwanted Copper is

removed. Etching is done by immersing the marked Copper clad in Ferric

Chloride solution. After that the etched sheet is dried.

9. The unwanted resist ink is removed using Sodium Hydroxide solution Holes

are then dried.

PCB PARAMETERS

Copper thickness - 72mil (1mm=39.37mils)

Track width - 60mil

Clearance - 60mil

Pad width - 86mil

Pad height - 86mil

Pad shape - Oval

Pad hole size - 25mil

On board - Through

Hole size - 0.9mm (36mil)

Base -Paper phenolic, Hylam


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SOLDERING

Soldering is the process of joining metals by using lower melting point to

weld or alloy with joining surface.

SOLDER

Solder is the joining materials that melt below 427 degree connections

between the components. The popularly used solders are alloys of tin (Sn) and

lead (Pb) that melts below melting point of tin.

Types:

1. Rosin core:- 60/40 Sn/Pb and 63/67 Sn/Pb solders are the most common types

used for electronics assembly. These solders are available in various diameters

and are most appropriate for small electronics work (0.02-0.05 dia. Is

recommended)

2. Lead free:- Lead free solders are used as more environmental-friendly

substitutes for leaded solder, but they are typically not as easy to use mainly

because of their higher melting point and poorer wetting properties.

3. Silver:- Silver solders are typically used for low resistance connections but

they have a higher melting point and are more expensive than sn/Pb solders.

4. Acid-Core:- Acid-Core solders should not be used for electronics. They are

intended for plumbing or non-electronics assembly work. The acid core flux

will cause corrosion of circuitry and can damage components.


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5. Other special solders:-

Various melting point eutectics: These special solders are typically used for non-

electronic assembly of difficult to construct mechanical items that must be

assembled in a particular sequence.

Paste solders: These solders are used in field applications or in specialized

manufacturing application.

Flux

In order to make the surface accept the solder readily, the components

terminals should be free Oxides and other obstructing films. The lead should be

cleaned chemically or by abrasion using blades or knives. Small amount of lead

coating can be done on the portion of the leads using soldering iron. Thisprocess is called thinning. Zinc chloride or Ammonium chloride separately or in

combination is mostly used as fluxes. These are available in petroleum jelly as

paste flux.

Flux is a medium used to remove the degree of wetting. The desirable

properties of flux are:-

It should provide a liquid cover over the materials and exclude air gap up to the

soldering temperature.

It should dissolve any Oxide on the metal surface.

It should be easily displaced from the metal by the molten soldering operation.

Residues should be removable after completing soldering operation.

The most common flux used in hand soldering of electronic components is

rosin, a combination of mild organic acids extracted from pine tree.


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Soldering Iron

It is the tool used to melt the solder and apply it at the joint in the circuit. It

operates in 230V supply. The iron bit at the tip gets heated while few minutes.

The 50W and 25W soldering irons are commonly used for soldering of

electronic circuits.

Soldering Steps

1. Make the layout of the components in the circuit. Plug in the chord of the

soldering iron into the mains to get heated.

2. Straighten and clean the component leads using a blade or a knife.

3. Mount the components on the PCB by bending the leads of the components.

Use nose pliers.

4. Apply flux on the joints and solder the joints. Soldering must be done in

minimum time to avoid dry soldering and heating up of the components.

5. Wash the residue using water and brush.

6. Solder joints should be inspected when completed to determine if they have

been properly made.


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Qualities of a good solder joint:

A. Shiny surface

B. Good, smooth fillet.

Properties of a poor solder joint:

1. Dull or crystallized surfaces:- this is an indicator of a cold solder joint. Cold

solder joint result from moving the components after the soldering has been

removed, but before the solder has hardened. Cold solder joints may work at

first, but will eventually fail.

2. Air pockets:- Air pockets (voids) result from incomplete wetting of surfaces,

allowing air to be in contact with the connecting metals. This will cause

oxidation of the joint and eventual failure. Blowholes can occur due to

vaporization of the moisture on the surface of the board and existing through the

molten solder. Boards should be clean and dry prior to soldering. Ethanol

(100%) can be used as a moisture chaser if boards are wet prior to soldering.

3. Dimples:- Dimples in the surface do not always indicate a serious problem,

but they should be avoided since they are precursors to voids.

4. Floaters:- Black spots floating in the soldering fillet should be avoided

because they indicate contamination and a potential for failure as in the case of

voids. These black spots usually result from overheated (burnt) Rosin or other

contaminants such as burnt wire insulation. Maintaining a clean tip will help to

avoid these problems.


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5. Balls:- A solder ball, instead of a fillet can occur if the trace was heated but

the lead was not (vice versa). This prevents proper wetting of both surfaces and

result in solder being attached to only one surface (component or trace).

6. Excess solder:- Excess solder usage can cover up other potential problems

and should be avoided. It can also lead to solder bridges. In addition, spherical

solder joints can result from the application of too much solder.


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PCB LAYOUT

CHAPTER 7


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PCB LAYOUT


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COMPONENT SIDE LAYOUT


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RESULTS

CHAPTER 8


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RESULTS

Speed of execution

We were able to run the ADC at its full speed with no problems. We ran the

PWM at 60Hz, however, since it was controlling DC motors. The blimp,

meanwhile, is light and has a large surface area and therefore encounters

significant drag. Its response time, therefore, was on the order of tenths of

seconds to seconds.

Accuracy

We examined the PWM signals on the oscilloscope to see their response to

the inputs from the gyroscope and proximty sensor via our algorithm. They

responded accurately and sensitively. The blimp did show some slight drift in

flight, but this could as well have been due to environmental conditions.

Otherwise, it was able to execute the required turns correctly.

Safety

Our blimp poses no significant safety concerns. The propeller blades aremade of soft plastic and did not cause any injury even when our fingers got in

the way. We inflated our balloon with hydrogen, which is inert. The risk of it

bursting as a result of being in contact with air was remote, but we considered it

nonetheless.

Usability

Our project, by virtue of its autonomy, is very easy to use. It requires only

the flick of a switch and it flies on its own. Suspending and securing thegondola, however, is most easily done with the assistance of a second person.


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CONCLUSION

CHAPTER 9


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CONCLUSION

Our blimp performed its navigational tasks correctly and successfully avoided

obstacles in its path. It flew untethered, and in these respects met the specifications

we had laid out. We had not, however, anticipated the difficulty of putting a

microcontroller circuit in the air, and we consider ourselves fortunate to have been

able to do so. Our design incorporated the bare essentials, and even then, it was a

Herculean task.

We were ultimately able to achieve our goal of keeping our circuit airborne by

taking a very minimalist approach to designing and building our project. However,

this was at the expense of many, many other things we would have like to do with

our project. We have already mentioned that we would have liked to implement a

more sophisticated navigation algorithm, with more sensors. We also toyed with

the idea of communicating obstacle locations via RF to another ground-based

MCU. We would also like to mount wireless cameras on board so that we can use

it as a low cost eye in sky replacing the costly satellites and their launches.

If we were to do this project again, we would (at the risk of exceeding the

budget) use two blimps instead of one, to largely eliminate the constraint of

weight, so that we could focus on working with the sensors etc. Nevertheless, it

was satisfying to push the envelope with just one blimp.


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DATASHEETS

CHAPTER 10


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Bibliography

1. Autonomous Blimp Project Prof.Garbini (University Of Washington)

2. Auto Blimp Morris, Ulloa (US Coast Guard Academy)

3. LISY 300 AL Datasheet

4. Microchip PIC Datasheet

5. IEEE Aerospace Magazine

Documents

Auto Blimp Report