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PID Observations

Posted by on Sunday, February 10, 2019 in Notebook.

PID Observations 

General behavior Characteristics:

  • Higher Proportional Control = Operates at defined setpoint
    • Higher fraction control here to force the fight between muscle activation and relaxed hand posture
  • Lower Proportional Control = Infinite rise in output value (operating in the single digits results in 10^6 outputs)
  • Higher Integral Control = Infinite rise in value although smoother slope established
    • The rise in output value must be counteracted either by a negative slope or much higher fraction of Proportional Control
  • Higher Fraction Differential Control = More exact value output (realistic to given input)
    • Most Exact control Here
  • Lower Fraction Differential Control = Less sine wave characteristics
    • Take the different in maximum amplitude within sliding window rather than the absolute given value to control the influence of the sine wave and the possible flutter

Coded PID Characteristics:

  • Tested with two different step functions and several sine wave inputs
  • Varied control across the three error schemes
  • Have defined set point of 0.5 to observe behavior
  • Finite loop that will be adjusted to operate in the sliding window that will later be defined

Needed for Code Improvement:

  • A break that defines the maximum amplitude in a window: once that is reached abort the loop and maintain this position until the maximum/minimum is redefined

Most Promising Output with Defined Constants General Control System:

  • Proportional : Integral : Differential = 1:0.008:0.5
  • Code in proportional change to prevent fluttering and exit loop when max. reached

*Output images blocked for upload, code with outputs updated in Github platform