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Everyday Control Feedback

  1. Nov 15, 2011 #1
    1. The problem statement, all variables and given/known data
    Identify 10 feedback systems that you encounter in your everyday environment. For each system, identify the sensing mechanism, actuation mechanism and control computation. Describe the uncertainty with respect to which the feedback system provides robustness and/or the dynamics that are changed through the use of feedback.


    2. Relevant equations
    NA

    3. The attempt at a solution

    1) Toilet water tank
    Sensing mechanism - Float
    Actuation mechanism - When the water level goes down, the float goes down which it opens the fill valve. As the water fills the tank, the float goes up & at a certain point, closes the fill valve.
    Control Computation - No idea
    Uncertainty/robustness etc - Not sure

    2) Cruise Control
    Sensing mechanism - whatever measures the speed in a car.
    Actuation - Solenoid driven throttle and brake?
    Control Compution - ?
    Uncertainty/Robustness - not sure

    3) Elevator
    Sensing mechanism - Sensors at each floor level.
    Actuation - Sensors stop the elevator?
    Control Compution -?
    Uncertainty/Robustness - not sure

    4) Climate Control
    Sensing mechanism - thermometer
    Actuation - ON/OFF of compressor.
    Control Compution - ?
    Uncertainty/Robustness - not sure


    ???
     
  2. jcsd
  3. Nov 15, 2011 #2

    berkeman

    User Avatar

    Staff: Mentor

    That's a great start! Keep going....

    Think of some that involve a human as the feedback part...

    Think of more electronic examples....

    You already have automotive cruise control, but how did the old steam engines control their speed...?
     
  4. Nov 15, 2011 #3
    Watt's governor :-)

    Anyway I have no idea what to write in the control computation, robustness etc etc.
     
    Last edited: Nov 15, 2011
  5. Nov 16, 2011 #4
    Hi Phiby, I will help with one of your current choices and maybe that can help with the others.

    2) Cruise Control
    Sensing mechanism - whatever measures the speed in a car. Tachometer/Speedometer
    Actuation - Solenoid driven throttle and brake? Good but lever not solenoid
    Control Compution - ? Comparison of desired set speed to actual speed
    Uncertainty/Robustness - not sure Makes adjustments for sudden changes in inclination (speeds up or slows down)
     
  6. Nov 16, 2011 #5
    Thank you. In Actuation - what lever are you referring to?
     
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