Difference between revisions of "ChaoticCircuits"

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  |Name=Chaotic circuits
 
  |Name=Chaotic circuits
 
  |Status=Completed
 
  |Status=Completed
  |Contact=gori
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  |Contact=User:Gori
 
  }}
 
  }}
  
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__FORCETOC__  
 
__FORCETOC__  
  
Build a simple electonic chaos demo for my course. Chaos can be observed using an oscilloscope. A portable one can be built with [http://code.google.com/p/arduinoscope/ an arduino]
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Build a simple electronic chaos demo for my course. Chaos can be observed using an oscilloscope. A portable one can be built with [http://code.google.com/p/arduinoscope/ an arduino]
  
 
== Background reading ==
 
== Background reading ==
*  One of the  simplest possible chaotic circuits : http://www-physics.ucsd.edu/~des/DSmithChaosExperiment.pdf
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*  One of the  simplest possible chaotic circuits: http://www-physics.ucsd.edu/~des/DSmithChaosExperiment.pdf
*   This one seems particularly interesting - possibility o encrypt analog sygnal : http://www.fortunecity.com/emachines/e11/86/circsync.html
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* This one seems particularly interesting - possibility o encrypt analog sygnal: http://www.fortunecity.com/emachines/e11/86/circsync.html
 
*  http://www.cornellcollege.edu/physics/courses/phy312/Student-Projects/Chaotic-circuits/Chaos.html
 
*  http://www.cornellcollege.edu/physics/courses/phy312/Student-Projects/Chaotic-circuits/Chaos.html
*  Original paper: [httphttp://link.aps.org/doi/10.1103/PhysRevLett.47.1349 Period Doubling and Chaotic Behavior in a Driven Anharmonic Oscillator]
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*  Original paper: [http://link.aps.org/doi/10.1103/PhysRevLett.47.1349 Period Doubling and Chaotic Behavior in a Driven Anharmonic Oscillator]
  
  
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Create the circuit that works at a lower frequency. Smith also describes a circuit that operates at 75 KHz instead of 2 MHz. Main bottle neck is the required large inductance
 
Create the circuit that works at a lower frequency. Smith also describes a circuit that operates at 75 KHz instead of 2 MHz. Main bottle neck is the required large inductance
  
Goal is to :
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Goal is to:
 
*  Be able to hear the chaos
 
*  Be able to hear the chaos
 
*  Have the whole thing portable, without the need for an external oscilloscope and signal generator
 
*  Have the whole thing portable, without the need for an external oscilloscope and signal generator
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Todo:
 
Todo:
 
*  Calculate the inductance and capacitance required to achieve a resonant frequency in the audible range, preferably around 440 Hz. Conservative human hearing range is from 20 Hz to 15 kHz.
 
*  Calculate the inductance and capacitance required to achieve a resonant frequency in the audible range, preferably around 440 Hz. Conservative human hearing range is from 20 Hz to 15 kHz.
*  Identify the operational limits of the [httphttp://code.google.com/p/arduinoscope/ arduinoscope] - max seems to be around 200 kHz, well above audible range
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*  Identify the operational limits of the [http://code.google.com/p/arduinoscope/ arduinoscope] - max seems to be around 200 kHz, well above audible range
 
*  Make sure that an arduino based scope can observe the signal.  
 
*  Make sure that an arduino based scope can observe the signal.  
 
*  salvage/build/buy an appropriate spool
 
*  salvage/build/buy an appropriate spool
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== Version 1.0 ==
 
== Version 1.0 ==
*  Following : http://www-physics.ucsd.edu/~des/DSmithChaosExperiment.pdf
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*  Following: http://www-physics.ucsd.edu/~des/DSmithChaosExperiment.pdf
 
*  Working oscilloscope  and signal generator present, capable of 2Mhz
 
*  Working oscilloscope  and signal generator present, capable of 2Mhz
*  Components according to the manual :
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*  Components according to the manual:
 
**  200 ohm resistor
 
**  200 ohm resistor
 
**  inductor, 100  microHenry needed, available a PE-53653 , with 16.1�H
 
**  inductor, 100  microHenry needed, available a PE-53653 , with 16.1�H
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*  As built, the circuit does not display any chaotic behavior as we change the amplitude, The inductor is almost 5 times to weak.
 
*  As built, the circuit does not display any chaotic behavior as we change the amplitude, The inductor is almost 5 times to weak.
 
*  I have several spools, adding an extra spool in series, bringing the inductance up to 32 �H does not help.  
 
*  I have several spools, adding an extra spool in series, bringing the inductance up to 32 �H does not help.  
*  When adding random spools, it is good to measure its inductance. Here is a way to do it : http://www.daycounter.com/Articles/How-To-Measure-Inductance.phtml
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*  When adding random spools, it is good to measure its inductance. Here is a way to do it: http://www.daycounter.com/Articles/How-To-Measure-Inductance.phtml
  
 
=== BOM ===
 
=== BOM ===
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**  Amplitude op 0 dB
 
**  Amplitude op 0 dB
 
**  sinus signaal
 
**  sinus signaal
*  Improvements needed :
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*  Improvements needed:
 
**  Calculate / measure the currently installed inductance, and bring it up to spec, so that we get a nicer signal split than now
 
**  Calculate / measure the currently installed inductance, and bring it up to spec, so that we get a nicer signal split than now
 
*  With smedings help, we determined that the inductance of the three coils is 1351 uH or approx 1.4 mH
 
*  With smedings help, we determined that the inductance of the three coils is 1351 uH or approx 1.4 mH
 
=== Results ===
 
=== Results ===
[[File:1-period.JPG]]
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<gallery>
[[File:2-period.JPG]]
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Image:1-period.JPG
[[File:4-period.JPG]]
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Image:2-period.JPG
[[File:8-period.JPG]]
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Image:4-period.JPG
[[File:chaos.JPG]]
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Image:8-period.JPG
[[File:circuit.JPG]]
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Image:chaos.JPG
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Image:circuit.JPG
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</gallery>

Latest revision as of 17:09, 26 November 2012

Project Chaotic circuits
Status Completed
Contact User:Gori
Last Update 2012-11-26

see also IgorsProjectIdeas


Build a simple electronic chaos demo for my course. Chaos can be observed using an oscilloscope. A portable one can be built with an arduino

Background reading


Version 2.0

Create the circuit that works at a lower frequency. Smith also describes a circuit that operates at 75 KHz instead of 2 MHz. Main bottle neck is the required large inductance

Goal is to:

  • Be able to hear the chaos
  • Have the whole thing portable, without the need for an external oscilloscope and signal generator
  • Have it nice and presentable so it can be used as a demo

Todo:

  • Calculate the inductance and capacitance required to achieve a resonant frequency in the audible range, preferably around 440 Hz. Conservative human hearing range is from 20 Hz to 15 kHz.
  • Identify the operational limits of the arduinoscope - max seems to be around 200 kHz, well above audible range
  • Make sure that an arduino based scope can observe the signal.
  • salvage/build/buy an appropriate spool
  • create a suitable analogue signal generator that can drive the whole thing. Arduino can no do this, as it has no analogue circuitry for the job. PWM will (propbably) not do.
  • Add speakers in order to hear the chaotic harmonics under/overtones
  • package it is something transparent so that it makes a nice demo


Version 1.0

  • Following: http://www-physics.ucsd.edu/~des/DSmithChaosExperiment.pdf
  • Working oscilloscope and signal generator present, capable of 2Mhz
  • Components according to the manual:
    • 200 ohm resistor
    • inductor, 100 microHenry needed, available a PE-53653 , with 16.1�H
    • diode - either works: 1N4001, 1N4004, 1N4005, 1N4007
  • As built, the circuit does not display any chaotic behavior as we change the amplitude, The inductor is almost 5 times to weak.
  • I have several spools, adding an extra spool in series, bringing the inductance up to 32 �H does not help.
  • When adding random spools, it is good to measure its inductance. Here is a way to do it: http://www.daycounter.com/Articles/How-To-Measure-Inductance.phtml

BOM

  • 1N4007 diode
  • 220 ohm resistor
  • (2 x 16) 32 �H + a random spool (code 471K 98139)
  • Signal:
    • 1.5 MHz
    • Amplitude op 0 dB
    • sinus signaal
  • Improvements needed:
    • Calculate / measure the currently installed inductance, and bring it up to spec, so that we get a nicer signal split than now
  • With smedings help, we determined that the inductance of the three coils is 1351 uH or approx 1.4 mH

Results