Class VotingEvaluator<T>

java.lang.Object
neqsim.process.logic.voting.VotingEvaluator<T>
Type Parameters:
T - type of input values (Boolean for digital, Double for analog)
public class VotingEvaluator<T> extends Object
Generic voting logic evaluator for redundant sensors or conditions.

Voting logic is used throughout process control and safety systems to increase reliability by requiring multiple independent signals to agree before taking action. This generic implementation supports:

  • Digital voting (boolean conditions: 1oo2, 2oo3, etc.)
  • Analog voting (continuous values: average, median, mid-value select)
  • Configurable voting patterns
  • Sensor fault detection and exclusion

Common applications:

  • Safety systems (HIPPS, Fire & Gas, ESD)
  • Critical process measurements (pressure, temperature, level)
  • Redundant control loops
  • Quality measurements

Example usage: 

// Digital voting: 2 out of 3 pressure switches must be high
VotingEvaluator<Boolean> pressureVoting = new VotingEvaluator<>(VotingPattern.TWO_OUT_OF_THREE);
pressureVoting.addInput(pt1.isHigh(), pt1.isFaulty());
pressureVoting.addInput(pt2.isHigh(), pt2.isFaulty());
pressureVoting.addInput(pt3.isHigh(), pt3.isFaulty());
boolean pressureHigh = pressureVoting.evaluateDigital();

// Analog voting: median of 3 temperature sensors
VotingEvaluator<Double> tempVoting = new VotingEvaluator<>(VotingPattern.TWO_OUT_OF_THREE);
tempVoting.addInput(tt1.getValue(), tt1.isFaulty());
tempVoting.addInput(tt2.getValue(), tt2.isFaulty());
tempVoting.addInput(tt3.getValue(), tt3.isFaulty());
double temperature = tempVoting.evaluateMedian();
Version:
1.0
Author:
ESOL

  • Field Details

  • Constructor Details

    • VotingEvaluator

      public VotingEvaluator(VotingPattern pattern)
      Creates a voting evaluator with specified pattern.
      Parameters:
      pattern - voting pattern (1oo1, 1oo2, 2oo2, 2oo3, etc.)

  • Method Details

    • addInput

      public void addInput(T value, boolean faulty)
      Adds an input to the voting group.
      Parameters:
      value - current value (Boolean or Double)
      faulty - true if this input is faulty

    • clearInputs

      public void clearInputs()
      Clears all inputs.

    • evaluateDigital

      public boolean evaluateDigital()
      Evaluates digital (boolean) voting.

      Counts how many non-faulty inputs are TRUE and applies voting pattern.

      Returns:
      true if voting condition is met
      Throws:
      IllegalStateException - if inputs are not Boolean type

    • evaluateMedian

      public double evaluateMedian()
      Evaluates analog voting using median selection.

      Returns the median value of non-faulty inputs. Median is preferred over average for safety systems as it's less sensitive to outliers.

      Returns:
      median value
      Throws:
      IllegalStateException - if inputs are not Double type or insufficient valid inputs

    • evaluateAverage

      public double evaluateAverage()
      Evaluates analog voting using average.
      Returns:
      average of non-faulty inputs
      Throws:
      IllegalStateException - if no valid inputs

    • evaluateMidValue

      public double evaluateMidValue()
      Evaluates analog voting using mid-value select.

      For 3 inputs, returns the middle value (not highest, not lowest). This provides some outlier rejection like median but is more intuitive for 3-input systems.

      Returns:
      mid-value
      Throws:
      IllegalStateException - if insufficient valid inputs

    • getPattern

      public VotingPattern getPattern()
      Gets the voting pattern.
      Returns:
      voting pattern

    • getValidInputCount

      public int getValidInputCount()
      Gets the number of valid (non-faulty) inputs.
      Returns:
      valid input count

    • getFaultyInputCount

      public int getFaultyInputCount()
      Gets the number of faulty inputs.
      Returns:
      faulty input count

    • getTotalInputCount

      public int getTotalInputCount()
      Gets the total number of inputs.
      Returns:
      total input count