# Everyday Control Feedback

## Homework Statement

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.

NA

## 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

???

berkeman
Mentor

## Homework Statement

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.

NA

## 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

???

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...?

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...?

Watt's governor :-)

Anyway I have no idea what to write in the control computation, robustness etc etc.

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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)

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)

Thank you. In Actuation - what lever are you referring to?