This class helps simulate linear systems. More...

#include <frc/simulation/LinearSystemSim.h>

Public Member Functions
	LinearSystemSim (const LinearSystem< States, Inputs, Outputs > &system, const std::array< double, Outputs > &measurementStdDevs={})
	Creates a simulated generic linear system. More...

virtual	~LinearSystemSim ()=default

void	Update (units::second_t dt)
	Updates the simulation. More...

const Vectord< Outputs > &	GetOutput () const
	Returns the current output of the plant. More...

double	GetOutput (int row) const
	Returns an element of the current output of the plant. More...

void	SetInput (const Vectord< Inputs > &u)
	Sets the system inputs (usually voltages). More...

void	SetInput (int row, double value)

void	SetState (const Vectord< States > &state)
	Sets the system state. More...

virtual units::ampere_t	GetCurrentDraw () const
	Returns the current drawn by this simulated system. More...

Protected Member Functions
virtual Vectord< States >	UpdateX (const Vectord< States > &currentXhat, const Vectord< Inputs > &u, units::second_t dt)
	Updates the state estimate of the system. More...

Vectord< Inputs >	ClampInput (Vectord< Inputs > u)
	Clamp the input vector such that no element exceeds the given voltage. More...

Protected Attributes
LinearSystem< States, Inputs, Outputs >	m_plant
	The plant that represents the linear system. More...

Vectord< States >	m_x
	State vector. More...

Vectord< Inputs >	m_u
	Input vector. More...

Vectord< Outputs >	m_y
	Output vector. More...

std::array< double, Outputs >	m_measurementStdDevs
	The standard deviations of measurements, used for adding noise to the measurements. More...

Detailed Description

template<int States, int Inputs, int Outputs>
class frc::sim::LinearSystemSim< States, Inputs, Outputs >

This class helps simulate linear systems.

To use this class, do the following in the simulationPeriodic() method.

Call the SetInput() method with the inputs to your system (generally voltage). Call the Update() method to update the simulation. Set simulated sensor readings with the simulated positions in the GetOutput() method.

Template Parameters

States	Number of states of the system.
Inputs	Number of inputs to the system.
Outputs	Number of outputs of the system.

Constructor & Destructor Documentation

◆ LinearSystemSim()

template<int States, int Inputs, int Outputs>

frc::sim::LinearSystemSim< States, Inputs, Outputs >::LinearSystemSim	(	const LinearSystem< States, Inputs, Outputs > &	system,
		const std::array< double, Outputs > &	measurementStdDevs = `{}`
	)

inlineexplicit

Creates a simulated generic linear system.

Parameters

system	The system to simulate.
measurementStdDevs	The standard deviations of the measurements.

◆ ~LinearSystemSim()

template<int States, int Inputs, int Outputs>

virtual frc::sim::LinearSystemSim< States, Inputs, Outputs >::~LinearSystemSim ( )

virtualdefault

Member Function Documentation

◆ ClampInput()

template<int States, int Inputs, int Outputs>

Vectord< Inputs > frc::sim::LinearSystemSim< States, Inputs, Outputs >::ClampInput ( Vectord< Inputs > u )

inlineprotected

Clamp the input vector such that no element exceeds the given voltage.

If any does, the relative magnitudes of the input will be maintained.

Parameters

u	The input vector.

Returns: The normalized input.

◆ GetCurrentDraw()

template<int States, int Inputs, int Outputs>

virtual units::ampere_t frc::sim::LinearSystemSim< States, Inputs, Outputs >::GetCurrentDraw ( ) const

inlinevirtual

Returns the current drawn by this simulated system.

Override this method to add a custom current calculation.

Returns: The current drawn by this simulated mechanism.

Reimplemented in frc::sim::DCMotorSim, frc::sim::ElevatorSim, frc::sim::FlywheelSim, and frc::sim::SingleJointedArmSim.

◆ GetOutput() [1/2]

template<int States, int Inputs, int Outputs>

const Vectord< Outputs > & frc::sim::LinearSystemSim< States, Inputs, Outputs >::GetOutput ( ) const

inline

Returns the current output of the plant.

Returns: The current output of the plant.

◆ GetOutput() [2/2]

template<int States, int Inputs, int Outputs>

double frc::sim::LinearSystemSim< States, Inputs, Outputs >::GetOutput ( int row ) const

inline

Returns an element of the current output of the plant.

Parameters

row	The row to return.

Returns: An element of the current output of the plant.

◆ SetInput() [1/2]

template<int States, int Inputs, int Outputs>

void frc::sim::LinearSystemSim< States, Inputs, Outputs >::SetInput ( const Vectord< Inputs > & u )

inline

Sets the system inputs (usually voltages).

Parameters

u	The system inputs.

◆ SetInput() [2/2]

template<int States, int Inputs, int Outputs>

void frc::sim::LinearSystemSim< States, Inputs, Outputs >::SetInput	(	int	row,
		double	value
	)

inline

◆ SetState()

template<int States, int Inputs, int Outputs>

void frc::sim::LinearSystemSim< States, Inputs, Outputs >::SetState ( const Vectord< States > & state )

inline

Sets the system state.

Parameters

state The new state.

◆ Update()

template<int States, int Inputs, int Outputs>

void frc::sim::LinearSystemSim< States, Inputs, Outputs >::Update ( units::second_t dt )

inline

Updates the simulation.

Parameters

dt	The time between updates.

◆ UpdateX()

template<int States, int Inputs, int Outputs>

virtual Vectord< States > frc::sim::LinearSystemSim< States, Inputs, Outputs >::UpdateX	(	const Vectord< States > &	currentXhat,
		const Vectord< Inputs > &	u,
		units::second_t	dt
	)

inlineprotectedvirtual

Updates the state estimate of the system.

Parameters

currentXhat	The current state estimate.
u	The system inputs (usually voltage).
dt	The time difference between controller updates.

Member Data Documentation

◆ m_measurementStdDevs

template<int States, int Inputs, int Outputs>

std::array<double, Outputs> frc::sim::LinearSystemSim< States, Inputs, Outputs >::m_measurementStdDevs

protected

The standard deviations of measurements, used for adding noise to the measurements.

◆ m_plant

template<int States, int Inputs, int Outputs>

LinearSystem<States, Inputs, Outputs> frc::sim::LinearSystemSim< States, Inputs, Outputs >::m_plant

protected

The plant that represents the linear system.

◆ m_u

template<int States, int Inputs, int Outputs>

Vectord<Inputs> frc::sim::LinearSystemSim< States, Inputs, Outputs >::m_u

protected

Input vector.

◆ m_x

template<int States, int Inputs, int Outputs>

Vectord<States> frc::sim::LinearSystemSim< States, Inputs, Outputs >::m_x

protected

State vector.

◆ m_y

template<int States, int Inputs, int Outputs>

Vectord<Outputs> frc::sim::LinearSystemSim< States, Inputs, Outputs >::m_y

protected

Output vector.

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

frc/simulation/LinearSystemSim.h

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ LinearSystemSim()

◆ ~LinearSystemSim()

Member Function Documentation

◆ ClampInput()

◆ GetCurrentDraw()

◆ GetOutput() [1/2]

◆ GetOutput() [2/2]

◆ SetInput() [1/2]

◆ SetInput() [2/2]

◆ SetState()

◆ Update()

◆ UpdateX()

Member Data Documentation

◆ m_measurementStdDevs

◆ m_plant

◆ m_u

◆ m_x

◆ m_y