Implements a PID control loop whose setpoint is constrained by a trapezoid profile. More...

#include <frc/controller/ProfiledPIDController.h>

Inheritance diagram for frc::ProfiledPIDController< Distance >:

Public Types
using	Distance_t = units::unit_t<Distance>

using	Velocity

using	Velocity_t = units::unit_t<Velocity>

using	Acceleration

using	Acceleration_t = units::unit_t<Acceleration>

using	State = typename TrapezoidProfile<Distance>::State

using	Constraints = typename TrapezoidProfile<Distance>::Constraints

Public Member Functions
constexpr	ProfiledPIDController (double Kp, double Ki, double Kd, Constraints constraints, units::second_t period=20_ms)
	Allocates a ProfiledPIDController with the given constants for Kp, Ki, and Kd.

constexpr	~ProfiledPIDController () override=default

constexpr	ProfiledPIDController (const ProfiledPIDController &)=default

constexpr ProfiledPIDController &	operator= (const ProfiledPIDController &)=default

constexpr	ProfiledPIDController (ProfiledPIDController &&)=default

constexpr ProfiledPIDController &	operator= (ProfiledPIDController &&)=default

constexpr void	SetPID (double Kp, double Ki, double Kd)
	Sets the PID Controller gain parameters.

constexpr void	SetP (double Kp)
	Sets the proportional coefficient of the PID controller gain.

constexpr void	SetI (double Ki)
	Sets the integral coefficient of the PID controller gain.

constexpr void	SetD (double Kd)
	Sets the differential coefficient of the PID controller gain.

constexpr void	SetIZone (double iZone)
	Sets the IZone range.

constexpr double	GetP () const
	Gets the proportional coefficient.

constexpr double	GetI () const
	Gets the integral coefficient.

constexpr double	GetD () const
	Gets the differential coefficient.

constexpr double	GetIZone () const
	Get the IZone range.

constexpr units::second_t	GetPeriod () const
	Gets the period of this controller.

constexpr double	GetPositionTolerance () const
	Gets the position tolerance of this controller.

constexpr double	GetVelocityTolerance () const
	Gets the velocity tolerance of this controller.

constexpr double	GetAccumulatedError () const
	Gets the accumulated error used in the integral calculation of this controller.

constexpr void	SetGoal (State goal)
	Sets the goal for the ProfiledPIDController.

constexpr void	SetGoal (Distance_t goal)
	Sets the goal for the ProfiledPIDController.

constexpr State	GetGoal () const
	Gets the goal for the ProfiledPIDController.

constexpr bool	AtGoal () const
	Returns true if the error is within the tolerance of the error.

constexpr void	SetConstraints (Constraints constraints)
	Set velocity and acceleration constraints for goal.

constexpr Constraints	GetConstraints ()
	Get the velocity and acceleration constraints for this controller.

constexpr State	GetSetpoint () const
	Returns the current setpoint of the ProfiledPIDController.

constexpr bool	AtSetpoint () const
	Returns true if the error is within the tolerance of the error.

constexpr void	EnableContinuousInput (Distance_t minimumInput, Distance_t maximumInput)
	Enables continuous input.

constexpr void	DisableContinuousInput ()
	Disables continuous input.

constexpr void	SetIntegratorRange (double minimumIntegral, double maximumIntegral)
	Sets the minimum and maximum contributions of the integral term.

constexpr void	SetTolerance (Distance_t positionTolerance, Velocity_t velocityTolerance=Velocity_t{ std::numeric_limits< double >::infinity()})
	Sets the error which is considered tolerable for use with AtSetpoint().

constexpr Distance_t	GetPositionError () const
	Returns the difference between the setpoint and the measurement.

constexpr Velocity_t	GetVelocityError () const
	Returns the change in error per second.

constexpr double	Calculate (Distance_t measurement)
	Returns the next output of the PID controller.

constexpr double	Calculate (Distance_t measurement, State goal)
	Returns the next output of the PID controller.

constexpr double	Calculate (Distance_t measurement, Distance_t goal)
	Returns the next output of the PID controller.

constexpr double	Calculate (Distance_t measurement, Distance_t goal, typename frc::TrapezoidProfile< Distance >::Constraints constraints)
	Returns the next output of the PID controller.

constexpr void	Reset (const State &measurement)
	Reset the previous error and the integral term.

constexpr void	Reset (Distance_t measuredPosition, Velocity_t measuredVelocity)
	Reset the previous error and the integral term.

constexpr void	Reset (Distance_t measuredPosition)
	Reset the previous error and the integral term.

void	InitSendable (wpi::SendableBuilder &builder) override
	Initializes this Sendable object.

Public Member Functions inherited from wpi::Sendable
virtual constexpr	~Sendable ()=default

Public Member Functions inherited from wpi::SendableHelper< ProfiledPIDController< Distance > >
constexpr	SendableHelper (const SendableHelper &rhs)=default

constexpr	SendableHelper (SendableHelper &&rhs)

constexpr SendableHelper &	operator= (const SendableHelper &rhs)=default

constexpr SendableHelper &	operator= (SendableHelper &&rhs)

Additional Inherited Members
Protected Member Functions inherited from wpi::SendableHelper< ProfiledPIDController< Distance > >
constexpr	SendableHelper ()=default

constexpr	~SendableHelper ()

Detailed Description

template<class Distance>
class frc::ProfiledPIDController< Distance >

Implements a PID control loop whose setpoint is constrained by a trapezoid profile.

Member Typedef Documentation

◆ Acceleration

template<class Distance >

using frc::ProfiledPIDController< Distance >::Acceleration

Initial value:

units::compound_unit<Velocity, units::inverse<units::seconds>>

units::compound_unit

typename units::detail::compound_impl< U, Us... >::type compound_unit

Represents a unit type made up from other units.

Definition base.h:1438

◆ Acceleration_t

template<class Distance >

using frc::ProfiledPIDController< Distance >::Acceleration_t = units::unit_t<Acceleration>

◆ Constraints

template<class Distance >

using frc::ProfiledPIDController< Distance >::Constraints = typename TrapezoidProfile<Distance>::Constraints

◆ Distance_t

template<class Distance >

using frc::ProfiledPIDController< Distance >::Distance_t = units::unit_t<Distance>

◆ State

template<class Distance >

using frc::ProfiledPIDController< Distance >::State = typename TrapezoidProfile<Distance>::State

◆ Velocity

template<class Distance >

using frc::ProfiledPIDController< Distance >::Velocity

Initial value:

units::compound_unit<Distance, units::inverse<units::seconds>>

◆ Velocity_t

template<class Distance >

using frc::ProfiledPIDController< Distance >::Velocity_t = units::unit_t<Velocity>

Constructor & Destructor Documentation

◆ ProfiledPIDController() [1/3]

template<class Distance >

frc::ProfiledPIDController< Distance >::ProfiledPIDController	(	double	Kp,
		double	Ki,
		double	Kd,
		Constraints	constraints,
		units::second_t	period = 20_ms )

inlineconstexpr

Allocates a ProfiledPIDController with the given constants for Kp, Ki, and Kd.

Users should call reset() when they first start running the controller to avoid unwanted behavior.

Parameters

Kp	The proportional coefficient. Must be >= 0.
Ki	The integral coefficient. Must be >= 0.
Kd	The derivative coefficient. Must be >= 0.
constraints	Velocity and acceleration constraints for goal.
period	The period between controller updates in seconds. The default is 20 milliseconds. Must be positive.

◆ ~ProfiledPIDController()

template<class Distance >

frc::ProfiledPIDController< Distance >::~ProfiledPIDController ( )

constexproverridedefault

◆ ProfiledPIDController() [2/3]

template<class Distance >

frc::ProfiledPIDController< Distance >::ProfiledPIDController ( const ProfiledPIDController< Distance > & )

constexprdefault

◆ ProfiledPIDController() [3/3]

template<class Distance >

frc::ProfiledPIDController< Distance >::ProfiledPIDController ( ProfiledPIDController< Distance > && )

constexprdefault

Member Function Documentation

◆ AtGoal()

template<class Distance >

bool frc::ProfiledPIDController< Distance >::AtGoal ( ) const

inlineconstexpr

Returns true if the error is within the tolerance of the error.

This will return false until at least one input value has been computed.

◆ AtSetpoint()

template<class Distance >

bool frc::ProfiledPIDController< Distance >::AtSetpoint ( ) const

inlineconstexpr

Returns true if the error is within the tolerance of the error.

Currently this just reports on target as the actual value passes through the setpoint. Ideally it should be based on being within the tolerance for some period of time.

This will return false until at least one input value has been computed.

◆ Calculate() [1/4]

template<class Distance >

double frc::ProfiledPIDController< Distance >::Calculate ( Distance_t measurement )

inlineconstexpr

Returns the next output of the PID controller.

Parameters

measurement The current measurement of the process variable.

◆ Calculate() [2/4]

template<class Distance >

double frc::ProfiledPIDController< Distance >::Calculate	(	Distance_t	measurement,
		Distance_t	goal )

inlineconstexpr

Returns the next output of the PID controller.

Parameters

measurement	The current measurement of the process variable.
goal	The new goal of the controller.

◆ Calculate() [3/4]

template<class Distance >

double frc::ProfiledPIDController< Distance >::Calculate	(	Distance_t	measurement,
		Distance_t	goal,
		typename frc::TrapezoidProfile< Distance >::Constraints	constraints )

inlineconstexpr

Returns the next output of the PID controller.

Parameters

measurement	The current measurement of the process variable.
goal	The new goal of the controller.
constraints	Velocity and acceleration constraints for goal.

◆ Calculate() [4/4]

template<class Distance >

double frc::ProfiledPIDController< Distance >::Calculate	(	Distance_t	measurement,
		State	goal )

inlineconstexpr

Returns the next output of the PID controller.

Parameters

measurement	The current measurement of the process variable.
goal	The new goal of the controller.

◆ DisableContinuousInput()

template<class Distance >

void frc::ProfiledPIDController< Distance >::DisableContinuousInput ( )

inlineconstexpr

Disables continuous input.

◆ EnableContinuousInput()

template<class Distance >

void frc::ProfiledPIDController< Distance >::EnableContinuousInput	(	Distance_t	minimumInput,
		Distance_t	maximumInput )

inlineconstexpr

Enables continuous input.

Rather then using the max and min input range as constraints, it considers them to be the same point and automatically calculates the shortest route to the setpoint.

Parameters

minimumInput	The minimum value expected from the input.
maximumInput	The maximum value expected from the input.

◆ GetAccumulatedError()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetAccumulatedError ( ) const

inlineconstexpr

Gets the accumulated error used in the integral calculation of this controller.

Returns: The accumulated error of this controller.

◆ GetConstraints()

template<class Distance >

Constraints frc::ProfiledPIDController< Distance >::GetConstraints ( )

inlineconstexpr

Get the velocity and acceleration constraints for this controller.

Returns: Velocity and acceleration constraints.

◆ GetD()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetD ( ) const

inlineconstexpr

Gets the differential coefficient.

Returns: differential coefficient

◆ GetGoal()

template<class Distance >

State frc::ProfiledPIDController< Distance >::GetGoal ( ) const

inlineconstexpr

Gets the goal for the ProfiledPIDController.

◆ GetI()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetI ( ) const

inlineconstexpr

Gets the integral coefficient.

Returns: integral coefficient

◆ GetIZone()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetIZone ( ) const

inlineconstexpr

Get the IZone range.

Returns: Maximum magnitude of error to allow integral control.

◆ GetP()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetP ( ) const

inlineconstexpr

Gets the proportional coefficient.

Returns: proportional coefficient

◆ GetPeriod()

template<class Distance >

units::second_t frc::ProfiledPIDController< Distance >::GetPeriod ( ) const

inlineconstexpr

Gets the period of this controller.

Returns: The period of the controller.

◆ GetPositionError()

template<class Distance >

Distance_t frc::ProfiledPIDController< Distance >::GetPositionError ( ) const

inlineconstexpr

Returns the difference between the setpoint and the measurement.

Returns: The error.

◆ GetPositionTolerance()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetPositionTolerance ( ) const

inlineconstexpr

Gets the position tolerance of this controller.

Returns: The position tolerance of the controller.

◆ GetSetpoint()

template<class Distance >

State frc::ProfiledPIDController< Distance >::GetSetpoint ( ) const

inlineconstexpr

Returns the current setpoint of the ProfiledPIDController.

Returns: The current setpoint.

◆ GetVelocityError()

template<class Distance >

Velocity_t frc::ProfiledPIDController< Distance >::GetVelocityError ( ) const

inlineconstexpr

Returns the change in error per second.

◆ GetVelocityTolerance()

template<class Distance >

double frc::ProfiledPIDController< Distance >::GetVelocityTolerance ( ) const

inlineconstexpr

Gets the velocity tolerance of this controller.

Returns: The velocity tolerance of the controller.

◆ InitSendable()

template<class Distance >

void frc::ProfiledPIDController< Distance >::InitSendable ( wpi::SendableBuilder & builder )

inlineoverridevirtual

Initializes this Sendable object.

Parameters

builder sendable builder

Implements wpi::Sendable.

◆ operator=() [1/2]

template<class Distance >

ProfiledPIDController & frc::ProfiledPIDController< Distance >::operator= ( const ProfiledPIDController< Distance > & )

constexprdefault

◆ operator=() [2/2]

template<class Distance >

ProfiledPIDController & frc::ProfiledPIDController< Distance >::operator= ( ProfiledPIDController< Distance > && )

constexprdefault

◆ Reset() [1/3]

template<class Distance >

void frc::ProfiledPIDController< Distance >::Reset ( const State & measurement )

inlineconstexpr

Reset the previous error and the integral term.

Parameters

measurement The current measured State of the system.

◆ Reset() [2/3]

template<class Distance >

void frc::ProfiledPIDController< Distance >::Reset ( Distance_t measuredPosition )

inlineconstexpr

Reset the previous error and the integral term.

Parameters

measuredPosition The current measured position of the system. The velocity is assumed to be zero.

◆ Reset() [3/3]

template<class Distance >

void frc::ProfiledPIDController< Distance >::Reset	(	Distance_t	measuredPosition,
		Velocity_t	measuredVelocity )

inlineconstexpr

Reset the previous error and the integral term.

Parameters

measuredPosition	The current measured position of the system.
measuredVelocity	The current measured velocity of the system.

◆ SetConstraints()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetConstraints ( Constraints constraints )

inlineconstexpr

Set velocity and acceleration constraints for goal.

Parameters

constraints Velocity and acceleration constraints for goal.

◆ SetD()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetD ( double Kd )

inlineconstexpr

Sets the differential coefficient of the PID controller gain.

Parameters

Kd	The differential coefficient. Must be >= 0.

◆ SetGoal() [1/2]

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetGoal ( Distance_t goal )

inlineconstexpr

Sets the goal for the ProfiledPIDController.

Parameters

goal	The desired unprofiled setpoint.

◆ SetGoal() [2/2]

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetGoal ( State goal )

inlineconstexpr

Sets the goal for the ProfiledPIDController.

Parameters

goal	The desired unprofiled setpoint.

◆ SetI()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetI ( double Ki )

inlineconstexpr

Sets the integral coefficient of the PID controller gain.

Parameters

Ki	The integral coefficient. Must be >= 0.

◆ SetIntegratorRange()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetIntegratorRange	(	double	minimumIntegral,
		double	maximumIntegral )

inlineconstexpr

Sets the minimum and maximum contributions of the integral term.

The internal integrator is clamped so that the integral term's contribution to the output stays between minimumIntegral and maximumIntegral. This prevents integral windup.

Parameters

minimumIntegral	The minimum contribution of the integral term.
maximumIntegral	The maximum contribution of the integral term.

◆ SetIZone()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetIZone ( double iZone )

inlineconstexpr

Sets the IZone range.

When the absolute value of the position error is greater than IZone, the total accumulated error will reset to zero, disabling integral gain until the absolute value of the position error is less than IZone. This is used to prevent integral windup. Must be non-negative. Passing a value of zero will effectively disable integral gain. Passing a value of infinity disables IZone functionality.

Parameters

iZone Maximum magnitude of error to allow integral control. Must be >= 0.

◆ SetP()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetP ( double Kp )

inlineconstexpr

Sets the proportional coefficient of the PID controller gain.

Parameters

Kp	The proportional coefficient. Must be >= 0.

◆ SetPID()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetPID	(	double	Kp,
		double	Ki,
		double	Kd )

inlineconstexpr

Sets the PID Controller gain parameters.

Sets the proportional, integral, and differential coefficients.

Parameters

Kp	The proportional coefficient. Must be >= 0.
Ki	The integral coefficient. Must be >= 0.
Kd	The differential coefficient. Must be >= 0.

◆ SetTolerance()

template<class Distance >

void frc::ProfiledPIDController< Distance >::SetTolerance	(	Distance_t	positionTolerance,
		Velocity_t	velocityTolerance = Velocity_t{ std::numeric_limits<double>::infinity()} )

inlineconstexpr

Sets the error which is considered tolerable for use with AtSetpoint().

Parameters

positionTolerance	Position error which is tolerable.
velocityTolerance	Velocity error which is tolerable.

The documentation for this class was generated from the following file:

frc/controller/ProfiledPIDController.h

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Acceleration

◆ Acceleration_t

◆ Constraints

◆ Distance_t

◆ State

◆ Velocity

◆ Velocity_t

Constructor & Destructor Documentation

◆ ProfiledPIDController() [1/3]

◆ ~ProfiledPIDController()

◆ ProfiledPIDController() [2/3]

◆ ProfiledPIDController() [3/3]

Member Function Documentation

◆ AtGoal()

◆ AtSetpoint()

◆ Calculate() [1/4]

◆ Calculate() [2/4]

◆ Calculate() [3/4]

◆ Calculate() [4/4]

◆ DisableContinuousInput()

◆ EnableContinuousInput()

◆ GetAccumulatedError()

◆ GetConstraints()

◆ GetD()

◆ GetGoal()

◆ GetI()

◆ GetIZone()

◆ GetP()

◆ GetPeriod()

◆ GetPositionError()

◆ GetPositionTolerance()

◆ GetSetpoint()

◆ GetVelocityError()

◆ GetVelocityTolerance()

◆ InitSendable()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ Reset() [1/3]

◆ Reset() [2/3]

◆ Reset() [3/3]

◆ SetConstraints()

◆ SetD()

◆ SetGoal() [1/2]

◆ SetGoal() [2/2]

◆ SetI()

◆ SetIntegratorRange()

◆ SetIZone()

◆ SetP()

◆ SetPID()

◆ SetTolerance()