Egg Incubator - Project Report

February 10, 2017 | Author: Juahir Bk | Category: N/A
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Effat   University     Students:   Haneen  Bawayan   Jauahir  Al-­‐‑Bakri   Maha  Nour   Maryam  Tora     Course  Instructor:   PROF.  Dr.  Muhammad   Ghazi  Shihata    

   

 

 

 

Saturday  Jan,  14,  2011    

 

EGG  INCUBATOR  

Outline … Abstract Introduction     Chapter  I:  Literature  Review   i.

What  Is  an  Egg  Incubator  

ii.

The  1st  Egg  Incubator  

iii.

Egg  Incubators  Time  Line  

  Chapter  II:  Class  Project  –  Chicken  Egg  Incubator   i.

Project  Objective  

ii.

Required  Circuits    

iii.

Incubator’s  Body    

iv.

Additional  Improvements    

  Chapter  III:  Class  Project  –  Problems,  Difficulties  and  Solutions   i.

In  Circuits  

  Conclusion       Appendix  A                  

   

2  

Abstract …   The   following   report   examines   the   combined   work   integrated   in   building   an   egg   incubator  for  hatching  bird  eggs;  the  project  was  the  result  of  the  collective  work  of  4   students  in  the  ECE  240  –  Linear  Control  System  course.     The   report   sheds   the   light   on   the   circuits   constructed,   the   mechanical   experience   gained  and  the  difficulties  faced  by  the  team  through  out  the  construction  process  over   the  span  of  5  weeks.  

Introduction … Since  the  dawn  of  time,  the  human  kind  had  used  the  eggs  of  animals  as  a  source  of   food,  wither  they  were  the  eggs  of  birds,  reptiles,  amphibians  or  fish  did  not  mater.  But   as  the  time  passed  the  humans  abilities  to  survive  improved  resulting  in  an  explosion   of   population   around   the   glob,   that   outburst   resulted   in   sustenance   becoming   a   challenge.  But  as  they  say  the  need  is  the  drive  behind  invention,  in  this  report,  one  of   these  inventions  –  The  Egg  Incubator  -­‐‑  is  built  and  discussed.     This  report  follows  through  with  the  work  of  this  group  over  the  span  of  5  weeks.  

                 

   

3  

Chapter I: Literature Review i.

What  Is  an  Egg  Incubator:   An  egg  incubator  is  used  to  hatch  bird  or  reptile  eggs.  The  incubator  keeps  the  eggs  warm,   allowing  the  fetuses  inside  of  them  to  grow  and  hatch  without  the  mother  present.  Each  bird   type  has  certain  properties  for  their  eggs  to  hatch  as  shown  in  the  table  bellow:       Humidity

Incub. Period

Temp

Humidity

Do not turn

(days)

(F.)¹

(F.)²

after

Chicken

21

99.5

85-87

18th day

90

18th day

Turkey

28

99

84-86

25th day

90

25th day

Species

Last

Open vent more

3 days²

Duck

28

99.5

85-86

25th day

90

25th day

Muscovy Duck

35-37

99.5

85-86

31st day

90

30th day

Goose

28-34

99

86-88

25th day

90

25th day

Guinea Fowl

28

99.5

85-87

25th day

90

24th day

Pheasant

23-28

99.5

86-88

21st day

92

20th day

Peafowl

28-30

99

84-86

25th day

90

25th day

Bobwhite Quail

23-24

99.5

84-87

20th day

90

20th day

Coturnix Quail

17

99.5

85-86

15th day

90

14th day

Chukar

23-24

99.5

81-83

20th day

90

20th day

Grouse

25

99.5

83-87

22nd day

90

21th day

Pigeon

17

99.5

85-87

15th day

90

14th day

   

ii.

The  1st  Egg  Incubator:   A   Napoleon   E.   Guerin   invented   the   first   egg   incubator   in   the   year   of   1843;   he   received   the   patent  for  his  creation  in  the  city  of  New  York    (No.  3,019).  The  patent  described  a  "ʺmode  of   distributing  steam  heat,  purifying  air,  etc."ʺ  for  hatching  chickens  by  artificial  heat.  

 

iii.

Egg  Incubators  Time  Line:   The  years  between  1843  and  2011  are  packed  with  substantial  developments  and  changes  on   the  original  work  of  Guerin,  and  can  not  possibly  fit  to  the  requirement  of  this  project’s  report,   thus;  for  additional  information  on  the  history  of  the  egg  incubator  please  refer  to  appendix  A.  

                 

4  

Chapter II: Class Project – Chicken Egg Incubator i.

Project  Objective:     The   resolve   of   this   project   was   to   build   a   complete,   fully   functioning   and   hand   made   egg   incubator   and   the   chosen   species   was   birds.   The   students   were   to   construct   a   design   for   the   egg   incubator   blocks   and   circuits.   After   finding   the   circuit   diagrams   corresponding   with   the   specifications  listed  by  the  course  instructor.  In  addition  to  the  experience,  the  students  had  an   opportunity  to  try  their  hands  in  the  mechanical  aspects  of  the  project  and  test  their  creative   capabilities.        

                                               

5  

 

ii.

Incubator  Design:   • Block  Diagram:  

 

iii.

Block  Diagram  Description:    

The  egg  incubator  consists  of  three  main  blocks,  which  they  are  the  temperature  controller  block,   humidity  control  block  and  motor  control  block.  First  off  all,  the  temperature  control  block  contain   fan  circuit  and  heater  circuit  to  keep  the  egg  incubator  temperature  suitable  for  the  eggs.  Second,  the   humidity  control  block  which  consist  of  water  level  circuit.  Finally,  Motor  movement  control  block.   This  block  consists  of  timer  circuit  that  allow  the  motor  to  move  from  time  to  time.  However,  the   motion  is  important  for  the  eggs  to  hatch,  but  not  in  all  days.  Therefore,  this  circuit  has  a  switch   connected  to  the  power  supply  to  open/close  it  when  its  needed.       All  of  them  are  supplied  by  12  V  power  supply.  That’s  why  there  is  a  switch  connected  to  the  power   supply  and  the  110  RMS.  It’s  the  main  switch  that  open  and  close  the  egg  incubator.  In  addition,  there   is  a  small  fan  connected  to  the  power  supply  so,  its  on  whenever  the  power  supply  is  open.  This  fan   is  to  cool  the  circuits  and  increase  the  incubator  life.         This  incubator  has  a  lamp  to  allow  the  user  to  see  what’s  happening  inside  it.  Also  it  can  be  use  as   additional  heater  if  needed.  This  lamp  has  an  external  switch  that  connects  it  with  110  RMS  to  turn  it   on/off  depends  on  the  user  needs.      

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  iv.

Required  Circuits:     • Heater  Circuit:    

Purpose:   The  purpose  of  this  circuit  is  to  control  the  temperature  also  inside  the  egg  incubator  by  keeping  the   egg   worm   as   in   their   real   environment.   This   circuit   opens   the   heater   when   the   temperature   value   goes   below   adjusted   temperature.   On   the   other   hands   its   turned   of   when   the   temperature   value   increase  above  the  adjusted  value  range.     Circuit  diagram:  

 

Parts:     -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐

50  K  Ω  NTC  Thermistor  (TTC05503)   OP-­‐‑  Amp  (UA  741  CN)   Transistor  2N2222   Potentiometer  to  100  K  Ω   DC  Power  supply  12  V     Resistors  (10  K,  5K,  50  K,  68  K,  150K,  10K,  20K,  4.7  K,  1k)     Capacitor  (0.01  !  F)   Electrode  capacitor  (10  !  F)   Relay     Diode   Air  heater  with  110  V              

7  

  Descripting:     This  circuit  is  also  has  the  50  K  Ω  thermistor  that  vary  inversely  with  the  temperature  as  shown  above   in   the   figure.   Consequently,   the   voltage   changes   across   the   thermistor   proportionally.   The   voltage   drop   across   the   thermistor   is   connected   to   the   positive   node   of   the   Op-­‐‑   Amp,   unlike   the   fan   circuit   when  it  was  connected  to  the  negative  node.  Furthermore,  The  voltage  drop  across  the  summation  of   resistors   R7   and   R8   is   connected   to   the   negative   node.   If   the   voltage   drop   in   the   positive   node   is   greater  than  the  voltage  in  the  negative  node,  then  the  Op-­‐‑Amp  value  will  be  enough  to  activate  the   transistor.  As  a  result,  the  current  will  bass  from  the  collector  to  the  emitter.  At  this  moment,  the  relay   close  its  switch  and  the  fan  will  be  on.  Otherwise  the  fan  will  be  in  the  off  mode.       For  example,  37  °C  was  the  required  temperature  value  to  reach  which  is  equivalent  to  30k  Ω  in  this   thermistor.  The  variable  resistor  was  adjusted  to  50k  Ω.  If  the  temperature  is  less  than  37  °C  that  mean   the   thermistor   value   is   above   30k  Ω.   therefore   the   voltage   across   the   thermistor   (positive   node)   is   greater  than  the  voltage  in  the  negative  node    (30k  Ω    =  R7  +  R8)  therefore  the  heater  is  on.     If  the  temperature  goes  above  37°C  that  means  the  thermistor  value  is  less  than  30  k  Ω.  furthermore,   the  voltage  in  the  positive  node  is  less  than  the  voltage  in  the  negative  node.  As  a  result  the  heater  is   off.    

                               

8  

    • Fan  Circuit:   Purpose:     The  purpose  of  this  circuit  is  to  control  the  temperature  of  the  egg  incubator.  When  the  temperature   increase   than   the   adjusted   temperature   (depends   on   the   egg   type)   the   fan   opens   to   cool   down   the   eggs.  Otherwise  it  will  be  close.     Circuit  diagram:  

 

Parts:     -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐  

50  k  Ω  NTC  thermistor  (TTC05503)   OP-­‐‑  Amp  (UA  741  CN)   Transistor  2N2222   Potentiometer  to  100  K  Ω   DC  Power  supply  12  V     Resistors  (15  K  ,  47  K  ,  20  K  ,150K,    1K,  5K,  20  K  ,  4.7  K  ,  1k)     Capacitor  (0.01  !  F)   Electrode  capacitor  (10  !  F)   Relay     Diode   Fan  with  110  V          

         

9  

  Descripting:   The   thermistor   shown   in   the   circuit   above   (50K   at   25  °C)   vary   depends   on   the   temperature   value.   When  the  temperature  increase  the  resistor  value  decrease  as  it  is  shown  in  the  figure  below:                                      

The  red  line  (TTC  05503)  is  the  behavior  of  50  k  

 

ohm  thermistor  

Therefore,   the   voltage   varies   across   the   thermistor.   The   voltage   drop   across   the   thermistor   is   connected   to   the   negative   node   of   the   Op-­‐‑   Amp.   On   the   other   hand,   the   voltage   drop   across   the   summation   of   resistors   R6,   R5   and   R7   is   connected   to   the   positive   node.   If   the   voltage   drop   in   the   positive  node  is  greater  than  the  voltage  in  the  negative  node,  then  the  Op-­‐‑Amp  value  will  be  enough   to  activate  the  transistor.  As  a  result,  the  current  will  bass  from  the  collector  to  the  emitter.     At  this  moment,  the  relay  close  its  switch  and  the  fan  will  be  on.  Otherwise,  the  fan  will  be  in  the  off   mode.       For  instance,  the  required  temperature  in  the  egg  incubator  was  37  °C  which  is  equivalent  to  26.5  k  Ω   in   this   thermistor.   Then   the   variable   resistor   was   adjusted   to   50   k  Ω.   now   if   the   temperature   is   less   that   37  °C   than   mean   the   thermistor   value   is   above   26.5   k  Ω.   therefore   the   voltage   in   this   node   (negative  node)  is  larger  than  the  voltage  across  the  26  k  Ω    (R6  +  R7  +  R8)  therefore  the  fan  is  off.    

   

10  

If  the  temperature  is  37  °C  exactly  then  the  fan  will  still  be  off  to  keep  the  required  temperature.  In  the   circuit,  if  it  was  37  °C  which  means  26.5  k  Ω  therefore  the  voltage  drop  across  it  is  still  higher  than  the   voltage  across  the  26k  Ω  (above  37  °C).  Therefore  the  fan  is  still  off.       Whenever  the  temperature  increase  above  37  °C  that  leads  to  decrease  the  thermistor  value  below  26   k  Ω.   that   cause   the   voltage   drop   across   the   26k  Ω  to   be   higher   than   the   voltage   drop   across   the   thermistor.  Therefore  the  fan  will  be  turn  on.    

                                                     

11  

  • Timer  Circuit:     Purpose:   The  purpose  for  this  circuit  is  to  control  the  motor  movement.  The  timer  circuit  moves  the  eggs  from   time  to  time  automatically  in  the  first  18th  day  then  the  user  should  switched  it  of  until  the  hatching   day.    This  circuit  is  designed  to  move  the  egg  90  sec  each  100  minutes.       Circuit  diagram:                

                   

  Parts:     -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐  

LM  555  Timer     Three  4.7  m  F  electrodes  capacitor     10  n  F  capacitor     Relay   Two  12  V  power  supply     Transistor  2N2222   Resistors  (10  K,  10  K,  360K)   Diode     Switch    

   

12  

Descripting:     555  Timer  was  used  to  control  the  motor  by  producing  pulses.  The  555  timer  used  for  this  purpose  to   produce  pluses  as  following:  

 

 

The   555-­‐‑timer   was   connected   as   shown   in   the   figure   to   be   in   pulse   generator   mode   (A   stable   Operation).  By  using  these  formulas:   The  charge  tome  (output  high)  is  given  by:   t1=  0.693  (RA+RB)C     The  discharge  (output  low)  is  given  by:   t2=  0.693  (RB)C     According  to  these  equations  the  circuits  were   designed  to  have:     RA  =  360  K  Ω   RB  =  10  K  Ω   C=  14.1  mF  (three  capacitor  in  parallel  with  4.7   m  F)       t1=  0.693  (360  K+10  K)  (14.1  m)  =  3615.381            =  85  minute  =1  hour  and  25  minute     t2  =    0.693  (10  K)  (14.1  m)  =  97.713              =  97  sec  =  1  minute  and  37  sec         As  its  clear  from  the  calculations  that  the  time  for  charging  (output  high)  is  larger  than  the  time  for   discharging   (output   low),   but   to   control   the   motor   movement   we   need   the   opposite.   Therefore   the      

13  

relay  was  connected  normally  short  and  when  there  is  current  passing  thorough  the  coil  (85  minutes)   its  will  disconnect  the  motor  (off  status)  and  when  no  current  passing  through  (97  sec)  the  relay  the   motor  will  be  connected  (turn  on  the  motor).      

                                                             

14  

  • Water  Level  Circuit:     Purpose:   The   purpose   for   this   circuit   is   to   control   the   humidity   inside   the   egg   incubator   by   controlling   the   water   level   in   a   tank   that   locates   inside   the   egg   incubator.   Therefore,   this   circuit   turns   on/off   the   pump  to  fill  the  tank  automatically  when  ever  the  water  level  decrease.     Circuit  diagram:  

 

Parts:     -­‐ -­‐ -­‐ -­‐ -­‐ -­‐ -­‐

2  input  NAND  gate  (HEF4011B)     Transistor  2N2222   DC  Power  supply  12  V     Resistors  (100  K,  100  K  ,  1  M,  1M  ,  4.7  K)     Relay     Diode   12  V  Pump    

                   

15  

Descripting:     The   water   level   circuit   consists   of   3   NAND   gates   that   are   taken   from   the   4   NAND   gates   in   IC   HEF4011B.   Two   of   the   NAND   gates   are   used   to   create   the  !"  flip   flop   as   shown   in   the   figure.   The  Third  NAND  gate’s  inputs  (2  input)  are  connected  together   and   the   NAND   gate’s   output   is   connected   to   the   reset   in   the  !"   Flip-­‐‑flop  as  you  can  see  in  the  circuit  diagram.     In   the   water   tank   there   are   the   threshold   sensor,   the   triggered   sensor   and   the   common   probe.   If   there   is   no   water   in   the   tank,   then   the   threshold   sensor   and   the   trigger   sensor   are   not   connected   to   the   common   probe   (the   ground).   This   mean   that   both  10  K  Ω  resistors  will  act  as  an  open  circuit  that  leads  to  have   high  voltage  drop  across  both  1  M  Ω  resistors.  As  a  result  the  set   node  in  the  !"  flip  flop  will  be  set  high  and  the  reset  node  will  be   !"  Flip  flop  with  2  NAND  gate      

set   low   because   the   two   inputs   to   the   NAND   gates   is   high.   Therefore,  the  !"  Flip-­‐‑flop  output  (!)  is  high,  which  activate  the   relay  to  turn  on  the  pump.       While   the   pump   is   open,   the   water   will   conduct   the   common   probe   with   the   trigger   sensor.   So,   the   two   NAND   gate’s   input   will  be  deactivated  and  its  out  put  will  be  high  (!=1).  The  water   doesn’t   reach   the   threshold   sensor   yet,   which   keep   the   set   node   in   the  !"  flip-­‐‑flop   activated.   In   this   case   when  !=1   and  !=1,   the   pump   will   continue   filling   because   the   out   put   of  !"  Flip-­‐‑flop   output  (!)  keep  the  old  status  of  the  last  output.       When  the  Water  reaches  the  threshold  sensor,  the  pump  will  be   turned  off.  Since  the  threshold  sensor  is  connected  to  the  ground   so  the  set  node  will  be  deactivated  (!=0).  Furthermore,  the  reset   node   will   be   activated   ( ! =1)   because   the   trigger   senor   is   connected   to   ground   and   the   output   of   the   NAND   gate   is   high   when   both   inputs   are   low.   Therefore   the   flip-­‐‑flop   output   (!)   is   deactivated  and  the  pump  is  turned  off.          

16  

 

v.

Incubator’s  Body:       The  incubator’s  body  was  constructed  from  wood,  this  was  the  only  task  not  performed  by  the   students   for   been   beyond   the   capacity   of   this   project.   A   carpenter   was   contracted   to   build   it   according  to  the  measurements  and  design  provided  by  the  team.     The  shell  was  the  only  thing  done  by  the  carpenter,  the  students  themselves  did  the  accessories   added  to  the  incubator  and  they  entitled  the  following:   •

Inner  roof  (  using  painting  board).  



The  glass  window  (from  old  printer).  



The  handles  on  the  door  and  the  roof.  



The  wheels  on  the  bottom  of  the  incubator.  



The  lamp,  fan,  heater,  motor,  circuits,  power  supply,  thermometer  and  two  switches.  

  vi.

Additional  Improvements:       The  main  parts  obligatory  were  the  circuits  for  the  fan,  heater,  motor  and  timer.  The  students   added  each  of  the  following  improvements  on  the  original  requirements:   •

The  Lamp:   A  60-­‐‑watt  bulb  was  added  to  help  the  user  check  on  the  eggs  in  the  dark.    



The  DC  Motor  Switch:   The   controlling   circuits   were   designed   according   the   specifications   required   to   hatch   Chickens  eggs.  According  to  them,  the  eggs  must  swing  for  90  sec  every  hour  for  the   duration  of  18  days  out  of  the  original  21  days,  hence  the  switch  to  enable  the  user  of   turning  the  DC  Motor’s  circuit  (responsible  for  the  swinging)  off.          

  •

The  Power  Supply  Switch:   Added  to  enable  the  user  of  On/Off  the  complete  incubator.  

                 

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Chapter III: Class Project – Problems, Difficulties and Solutions i.

In  Circuits:   • Heater  Circuit:    

This  circuit  was  done  on  the  same  concept  of  the  fan  circuit  with  some  differences.  Although,  it  didn’t   work  from  the  first  time,  then  it  was  noticed  that  it  is  an  open  circuit  (testing  board  circuits  has  near   nodes  we  thoughts  it  is  connected  but  it  was  connected  to  the  node  below  it).     While  testing  this  circuit  at  the  beginning,  the  heater  device  was  not  decided  yet.  Therefore,  we  used   a  lamp  instead  to  represent  the  heater.  When  lamp  is  on  that  indicate  the  heater  is  on  otherwise  it’s   off.  After  that,  a  hair  drier  (with  110V)  was  chosen  to  be  the  heater  for  the  egg  incubator  and  the  lamp   was  replaced.  However,  the  circuit  did  a  great  job  while  testing  it  as  you  can  see  in  the  link  below:       http://www.youtube.com/watch?v=uXLyK-­‐‑SczVs  

  • Lamp:     A  lamp  was  connected  to  the  switch  and  then  to  the  110  V.    This  connection  was  connected  in  wrong   way  that  creates  a  short  circuit  between  the  two  nods  of  the  110  V.    Thus,  when  the  switch  was  turned   on  the  plug  is  burned.  After  that,  the  mistake  was  noticed  and  it  was  corrected.    

                           

18  

• Fan  Circuit:     The  following  difficulties  were  faced  with  the  fan  circuit:     -­‐

Wrong  connection  of  the  mechanical  relay  due  to  the  lack  of  knowledge  on  how  it  operates,   the  connections  between  its  pins.  This  problem  was  solved  by  opining  one  of  the  mechanical   relays  and  studding  its  inner  configuration  vie  a  voltmeter.  

-­‐

A  47  KΩ  was  used  in  the  beginning  but  it  was  replaced  by  a  4.7  KΩ  after  studding  the  data   sheet.  

-­‐

The  testing  of  the  thermistor  during  different  temperatures  in  order  to  compare  the  obtained   results  with  the  ones  provided  by  the  data  sheet,  which  proved  to  be  somewhat  difficult  with  a   digital  thermometer  due  to  the  sudden  -­‐‑  instead  of  gradual  -­‐‑  changes  in  temperature.  

-­‐

In  order  to  understand  the  circuit,  the  team  had  to  learn  how  to  read  the  algorithm  provided   by  the  data  sheet.  

-­‐

The  circuit  was  simulated  using  multi-­‐‑sim  software;  the  circuit’s  behavior  was  studied  by   calculating  the  output  voltage  at  different  nodes  that  corresponds  to  different  values  of   resistors.    

-­‐

The  resistor  values  used  in  the  circuit  diagram  were  connected  on  series,  that  connection   proved  inefficient  for  the  team’s  purpose;  hence  they  were  connected  on  the  parallel.  

-­‐

The  variable  resistor  was  unstable  leading  to  soldering  its  three  pins  to  a  hard  wire  and  then   connecting  it  to  the  circuit.  

-­‐

The  circuit  was  tested  on  a  12Vcc  fan,  after  it  was  proven  to  work  successfully;  the  fan  was   replaced  with  the  110Vcc  intended  fan.    

-­‐

The  plug  connecting  the  fan  to  the  110Vcc  was  unsteady,  resulting  in  constant  checking  on  its   connection  state.  The  plug  was  replaced  and  he  problem  was  solved.  

-­‐

The  fan  was  situated  inside  the  incubator  without  any  holes  to  ventilate  it,  the  mistake  was   later  noticed  and  holes  were  added  via  a  wood  drill.     At  the  end  all  the  problems  were  fixed  and  the  circuit  was  tested.  Please  check  the  link  below:   http://www.youtube.com/watch?v=UzHUmJI12XE&feature=related      

           

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  • Timer  Circuit:     At  the  beginning  the  timer  circuit  was  connected  in  a  way  such  that  it  functioned  in  a  mono  stable   mode,   which   produce   only   one   pulse.   After   going   through   the   datasheet   again   and   analyzing   it   carefully,   we   reconnected   the   circuit   to   be   in   the   astable   mode,   in   order   for   it   to   act   as   a   pulse   generator.   To  test  the  astable  mode  we  connected  a  lamp  with  6V  instead  of  the  actual  motor,  because  it’s  easier   to  observe  the  change.  Since,  the  lamp  is  smaller  in  size  and  is  very  easy  to  more  around  in  case  of   connection  changes.   By  using  !! = 10!Ω, !! = 4.7!Ω  and  calculating  the  time  for  turning  ON/OFF  the  lamp,  it  was  found   that  !! = 3,257 sec !" , !! = 10.187 sec !"" .   After   testing,   the   results   were  !! = 3.4 sec, !! = 11  !"#.   The  results  were  expected.   After   that   we   changed   the   values   of   both  !! , !!  with   the   (capacitance=100µμF),   as   a   result,  !! = 90 sec, !! = 100  !"#$%&',   according   to   the   required   output,   the   values   of   both   resistors   were   determined,   such   that!! = 51.7!Ω, !! = 216.45!Ω.   Later,   we   noticed   that   the   values   are   too   high,   the  resistors  act  as  an  open  circuit,  and  the  lamp  never  turns  ON  because  the  resistors  dissipate  the   current.   Therefore,   we   decided   to   increase   the   value   of   the   capacitor   instead   of   the   resistor.   Consequently,  we  took  a  capacitor  with  a  value  of  1000µμF  from  an  old  power  supply.  We  recalculated   the   values   all   over   again,   after   that,   we   the!! = 5.1!Ω, !! = 21.65!Ω.   After   testing   the   circuit   with   these  values,  it  was  found  that  the  lamp  was  also  switched  ON  all  the  time,  because  !! = 5.1!Ω  acts   as  an  open  circuit  because  of  its  high  value.   To  solve  this  problem,  we  suggested,  instead  of  increasing  the  resistor  value  we  should  increase  the   capacitance,   therefore   we   created   a   schedule   depending   on   the   largest   value   of   capacitance   the   electronic  shop  had  available  which  was  (4.7mF).  Finally,  we  connected  three  capacitors  in  parallel  to   get  a  greater  value,  ! = 4.7! + 4.7! + 4.7! =  14.7!".       !! = 0.693 14.1! 10! = 1!"#$%&, 37  !"#$%&!   !! = 0.693 14.1! 10! + 360! = 1ℎ!"#, 25!"#$%& = 85!"#$%&'     The   circuit   was   then   tested,   by   placing   a   camera   in   front   of   the   circuit   for   two   hours.   After   going   through  the  film,  we  found  out  that  it  took  1  hour  and  39  minutes  for  the  lamp  to  be  switched  ON,   and  it  stayed  ON  for  90  seconds,  then  it  was  turned  OFF  again.  The  link  below  show  the  timer  circuits   test:   http://www.youtube.com/watch?v=TaNMxzs7V-­‐‑o        

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Finally,  the  last  result  was  the  result  we  took,  the  values  were  obtained  from  it  and  we  designed  the   circuit  accordingly.  Even  though  there  was  a  14-­‐‑minute  error,  it  is  an  acceptable  error  and  hopefully   it  will  not  affect  the  eggs.      

• Water  Level  Circuit:     -­‐

 

At   the   beginning   the   circuit   didn’t   work   normally   as   it   should   to.   Then   after   checking   all   components  in  the  circuit,  we  realized  that  there  is  no  connection  between  pin  3  and  5  in  the   NAND  gate.  This  missing  wire  is  responsible  for  the  connection  between  the  output  of  NAND   gate  and  the  reset  in  !"  flip-­‐‑flop.    

-­‐

The  pump  didn’t  work  when  it  was  connected  to  the  power  supply.  Suddenly  we  noticed  that   the  pump  has  negative  and  positive  polarities  so,  the  problem  was  fixed.    

-­‐

When  the  pump’s  ends  were  connected  to  hose,  the  pump  didn’t  work  until  one  of  the  ends   (the   one   that   suction   water   from   the   water   storage   tank)   connected   directly   to   the   water   surface.    

-­‐

Relay   was   not   working   (factor   default).   Then   it   was   changed   with   a   new   one   and   t   worked   correctly.  

-­‐ -­‐

While  connecting  the  sensors  in  the  water  tank,  that  is  made  from  plastic,           the  water  tank  broke.  Soldering  machine  was  used  to  solve  the  problem  by  melting  a  little  part  

 

 

 

of  the  plastic  and  reappear  the  broken  part.  Also,  the  soldering  device  was  used  to  create  small   wholes  to  allow  screws  to  enter  the  plastic  without  breaking  it.  In  addition,  silicon  was  used  to   prevent  water  leakage.       -­‐

At   the   end   all   the   problems   were   fixed   and   the   circuit   was   tested   as   you   can   see   in   the   link   below:    

 

http://www.youtube.com/watch?v=LmVbmCQTtjA  

 

             

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Conclusion: The  objectives  behind  the  project  were  fulfilled,  from  understanding  the  art  of  constructing  circuits  to   creating  our  on  electrical  drill!!  Add  to  that  the  acquired  experience  in  facing  the  different  types  of   problems  and  brain  storming  their  solutions.     In  the  end;  the  egg  incubator  worked  successfully,  the  circuits  functioned  at  the  set  controls  and  the   body  was  constructed  to  fit  the  different  elements  integrated  to  produce  the  incubator.    

Appendix A: The  time  Line  of  the  Egg  Incubator:      1843  

On   Mar   30,   1843   Napoleon   E.   Guerin   of   New   York   City,   received   a   patent   for   an   "ʺEgg   Hatching   Apparatus"ʺ  (mode  of  distributing  steam  heat,  purifying  air,  etc."ʺ);  egg  incubator  for  hatching  chickens   by  artificial  heat.      1879  

In   1879,   Lyman   Byce   and   Isaac   Dias   invented   the   first   practical   egg   incubator.   Another   Petaluman,   Christopher  Nisson,  seized  upon  this  invention  and  within  a  few  years  had  established  the  world'ʹs   first  commercial  hatchery.        1947   Feb  11,  1947  -­‐‑   A  new  10000-­‐‑egg  incubator  has  been  installed  in  the  poultry  building.  The  new  brooder   house  is  de  signed  to  brood  1700  poults  "ʺoff  he  floor,"ʺ  while  a  second  unit  to  be  constructed  later  will   make  "ʺon  the  floor"ʺ  brooding  for  comparison.      1963  

Apr  13,  1963  -­‐‑   The  first  graders  at  Davis  Elementary  School  had  been  told  chickens  came  from  eggs   but   they   weren'ʹt   sure   until   they   saw   it   actually   happen.   They   had   been   watching   the   egg   in   an   improvised  incubator.      

   

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References: http://www.vishay.com/docs/29049/23816403.pdf   http://www.es.co.th/Schemetic/PDF/TTC05.PDF   http://pdf1.alldatasheet.com/datasheet-­‐‑pdf/view/17675/PHILIPS/HEF4011BT.html   http://en.wikipedia.org/wiki/Flip-­‐‑flop_(electronics)   http://www.todayinsci.com/3/3_30.htm   http://www.poultryhelp.com/hatch.html          

   

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