org.lsst.ccs.subsystem.common

Class PIDController

java.lang.Object

org.lsst.ccs.subsystem.common.PIDController

public class PIDController
extends Object

Proportional, Integral, Differential controller This PID Controller class implements a proportional, integral, derivative controller for use in the thermal control of the LSST camera electronics.

Author:

CCS Team

Constructor Summary

Constructors

Constructor and Description
PIDController(String callerPath) Allocate a PI object with the given constants for P, I

Method Summary

Modifier and Type	Method and Description
double	getCoefD() Get the Derivative coefficient
double	getCoefI() Get the Integral coefficient
double	getCoefP() Get the Proportional coefficient
double	getError() Returns the current difference of the input from the setpoint
double	getInput() Returns the current smoothed input
double	getIntegral() Returns the current error integral
double	getSetpoint() Returns the current setpoint of the PIDController
double	getTimeConst() Get the Integral coefficient
double	performPID(double[] input, double time) Return the current PI result.
void	reset() Reset the previous error, the integral, and disable the controller.
void	setBaseOutput(double value) Sets the base output.
void	setCoefD(double value) Set the Derivative coefficient
void	setCoefI(double value) Set the Integral coefficient
void	setCoefP(double value) Set the Proportional coefficient
void	setInputRange(double minimumInput, double maximumInput) Sets the maximum and minimum values expected from the input.
void	setIntegral(double value) Sets the error integral
void	setOutputRange(double minimumOutput, double maximumOutput) Sets the minimum and maximum values to write.
void	setSetpoint(double setpnt) Set the setpoint for the PIDController
void	setSmoothTime(double time) Sets the smoothing time.
void	setTimeConst(double time) Set the time constant characterizing the integration

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PIDController

public PIDController(String callerPath)

Allocate a PI object with the given constants for P, I

Method Detail

performPID

public double performPID(double[] input,
                         double time)

Return the current PI result. This is constrained by the max and min outs

Parameters:

input - The array of input values

time - The measurement time

Returns:

the latest calculated output

setTimeConst

public void setTimeConst(double time)

Set the time constant characterizing the integration

Parameters:

time - Integral coefficient (integration time constant)

setSmoothTime

public void setSmoothTime(double time)

Sets the smoothing time.

Parameters:

time - the smoothing time

setCoefP

public void setCoefP(double value)

Set the Proportional coefficient

Parameters:

value - proportional coefficient

setCoefI

public void setCoefI(double value)

Set the Integral coefficient

Parameters:

value - integral coefficient

setCoefD

public void setCoefD(double value)

Set the Derivative coefficient

Parameters:

value - derivative coefficient

getCoefP

public double getCoefP()

Get the Proportional coefficient

Returns:

proportional coefficient

getCoefI

public double getCoefI()

Get the Integral coefficient

Returns:

integral coefficient

getCoefD

public double getCoefD()

Get the Derivative coefficient

Returns:

derivative coefficient

getTimeConst

public double getTimeConst()

Get the Integral coefficient

Returns:

integral coefficient

setBaseOutput

public void setBaseOutput(double value)

Sets the base output.

Parameters:

value - the base output value

setInputRange

public void setInputRange(double minimumInput,
                          double maximumInput)

Sets the maximum and minimum values expected from the input.

Parameters:

minimumInput - the minimum value expected from the input

maximumInput - the maximum value expected from the output

setOutputRange

public void setOutputRange(double minimumOutput,
                           double maximumOutput)

Sets the minimum and maximum values to write.

Parameters:

minimumOutput - the minimum value to write to the output

maximumOutput - the maximum value to write to the output

setSetpoint

public void setSetpoint(double setpnt)

Set the setpoint for the PIDController

Parameters:

setpnt - the desired setpoint

getSetpoint

public double getSetpoint()

Returns the current setpoint of the PIDController

Returns:

the current setpoint

getError

public double getError()

Returns the current difference of the input from the setpoint

Returns:

the current error

getIntegral

public double getIntegral()

Returns the current error integral

Returns:

the current error integral

setIntegral

public void setIntegral(double value)

Sets the error integral

Parameters:

value - the error integral value to set

getInput

public double getInput()

Returns the current smoothed input

Returns:

the current smoothed input

reset

public void reset()

Reset the previous error, the integral, and disable the controller.