#include <frc/simulation/DifferentialDrivetrainSim.h>

Classes
class	KitbotGearing
	Represents a gearing option of the Toughbox mini. More...

class	KitbotMotor
	Represents common motor layouts of the kit drivetrain. More...

class	KitbotWheelSize
	Represents common wheel sizes of the kit drivetrain. More...

class	State

Public Member Functions
	DifferentialDrivetrainSim (LinearSystem< 2, 2, 2 > plant, units::meter_t trackWidth, DCMotor driveMotor, double gearingRatio, units::meter_t wheelRadius, const std::array< double, 7 > &measurementStdDevs={})
	Creates a simulated differential drivetrain.

	DifferentialDrivetrainSim (frc::DCMotor driveMotor, double gearing, units::kilogram_square_meter_t J, units::kilogram_t mass, units::meter_t wheelRadius, units::meter_t trackWidth, const std::array< double, 7 > &measurementStdDevs={})
	Creates a simulated differential drivetrain.

Eigen::Vector2d	ClampInput (const Eigen::Vector2d &u)
	Clamp the input vector such that no element exceeds the battery voltage.

void	SetInputs (units::volt_t leftVoltage, units::volt_t rightVoltage)
	Sets the applied voltage to the drivetrain.

void	SetGearing (double newGearing)
	Sets the gearing reduction on the drivetrain.

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

double	GetGearing () const
	Returns the current gearing reduction of the drivetrain, as output over input.

Rotation2d	GetHeading () const
	Returns the direction the robot is pointing.

Pose2d	GetPose () const
	Returns the current pose.

units::meter_t	GetRightPosition () const
	Get the right encoder position in meters.

units::meters_per_second_t	GetRightVelocity () const
	Get the right encoder velocity in meters per second.

units::meter_t	GetLeftPosition () const
	Get the left encoder position in meters.

units::meters_per_second_t	GetLeftVelocity () const
	Get the left encoder velocity in meters per second.

units::ampere_t	GetRightCurrentDraw () const
	Returns the currently drawn current for the right side.

units::ampere_t	GetLeftCurrentDraw () const
	Returns the currently drawn current for the left side.

units::ampere_t	GetCurrentDraw () const
	Returns the currently drawn current.

void	SetState (const Vectord< 7 > &state)
	Sets the system state.

void	SetPose (const frc::Pose2d &pose)
	Sets the system pose.

Vectord< 7 >	Dynamics (const Vectord< 7 > &x, const Eigen::Vector2d &u)
	The differential drive dynamics function.

Static Public Member Functions
static DifferentialDrivetrainSim	CreateKitbotSim (frc::DCMotor motor, double gearing, units::meter_t wheelSize, const std::array< double, 7 > &measurementStdDevs={})
	Create a sim for the standard FRC kitbot.

static DifferentialDrivetrainSim	CreateKitbotSim (frc::DCMotor motor, double gearing, units::meter_t wheelSize, units::kilogram_square_meter_t J, const std::array< double, 7 > &measurementStdDevs={})
	Create a sim for the standard FRC kitbot.

Constructor & Destructor Documentation

◆ DifferentialDrivetrainSim() [1/2]

frc::sim::DifferentialDrivetrainSim::DifferentialDrivetrainSim	(	LinearSystem< 2, 2, 2 >	plant,
		units::meter_t	trackWidth,
		DCMotor	driveMotor,
		double	gearingRatio,
		units::meter_t	wheelRadius,
		const std::array< double, 7 > &	measurementStdDevs = {} )

Creates a simulated differential drivetrain.

Parameters

plant	The LinearSystem representing the robot's drivetrain. This system can be created with LinearSystemId::DrivetrainVelocitySystem() or LinearSystemId::IdentifyDrivetrainSystem().
trackWidth	The robot's track width.
driveMotor	A DCMotor representing the left side of the drivetrain.
gearingRatio	The gearingRatio ratio of the left side, as output over input. This must be the same ratio as the ratio used to identify or create the plant.
wheelRadius	The radius of the wheels on the drivetrain, in meters.
measurementStdDevs	Standard deviations for measurements, in the form [x, y, heading, left velocity, right velocity, left distance, right distance]ᵀ. Can be omitted if no noise is desired. Gyro standard deviations of 0.0001 radians, velocity standard deviations of 0.05 m/s, and position measurement standard deviations of 0.005 meters are a reasonable starting point.

◆ DifferentialDrivetrainSim() [2/2]

frc::sim::DifferentialDrivetrainSim::DifferentialDrivetrainSim	(	frc::DCMotor	driveMotor,
		double	gearing,
		units::kilogram_square_meter_t	J,
		units::kilogram_t	mass,
		units::meter_t	wheelRadius,
		units::meter_t	trackWidth,
		const std::array< double, 7 > &	measurementStdDevs = {} )

Creates a simulated differential drivetrain.

Parameters

driveMotor	A DCMotor representing the left side of the drivetrain.
gearing	The gearing on the drive between motor and wheel, as output over input. This must be the same ratio as the ratio used to identify or create the plant.
J	The moment of inertia of the drivetrain about its center.
mass	The mass of the drivebase.
wheelRadius	The radius of the wheels on the drivetrain.
trackWidth	The robot's track width, or distance between left and right wheels.
measurementStdDevs	Standard deviations for measurements, in the form [x, y, heading, left velocity, right velocity, left distance, right distance]ᵀ. Can be omitted if no noise is desired. Gyro standard deviations of 0.0001 radians, velocity standard deviations of 0.05 m/s, and position measurement standard deviations of 0.005 meters are a reasonable starting point.

Member Function Documentation

◆ ClampInput()

Eigen::Vector2d frc::sim::DifferentialDrivetrainSim::ClampInput ( const Eigen::Vector2d & u )

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

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

Parameters

u	The input vector.

Returns: The normalized input.

◆ CreateKitbotSim() [1/2]

static DifferentialDrivetrainSim frc::sim::DifferentialDrivetrainSim::CreateKitbotSim	(	frc::DCMotor	motor,
		double	gearing,
		units::meter_t	wheelSize,
		const std::array< double, 7 > &	measurementStdDevs = {} )

inlinestatic

Create a sim for the standard FRC kitbot.

Parameters

motor	The motors installed in the bot.
gearing	The gearing reduction used.
wheelSize	The wheel size.
measurementStdDevs	Standard deviations for measurements, in the form [x, y, heading, left velocity, right velocity, left distance, right distance]ᵀ. Can be omitted if no noise is desired. Gyro standard deviations of 0.0001 radians, velocity standard deviations of 0.05 m/s, and position measurement standard deviations of 0.005 meters are a reasonable starting point.

◆ CreateKitbotSim() [2/2]

static DifferentialDrivetrainSim frc::sim::DifferentialDrivetrainSim::CreateKitbotSim	(	frc::DCMotor	motor,
		double	gearing,
		units::meter_t	wheelSize,
		units::kilogram_square_meter_t	J,
		const std::array< double, 7 > &	measurementStdDevs = {} )

inlinestatic

Create a sim for the standard FRC kitbot.

Parameters

motor	The motors installed in the bot.
gearing	The gearing reduction used.
wheelSize	The wheel size.
J	The moment of inertia of the drivebase. This can be calculated using SysId.
measurementStdDevs	Standard deviations for measurements, in the form [x, y, heading, left velocity, right velocity, left distance, right distance]ᵀ. Can be omitted if no noise is desired. Gyro standard deviations of 0.0001 radians, velocity standard deviations of 0.05 m/s, and position measurement standard deviations of 0.005 meters are a reasonable starting point.

◆ Dynamics()

Vectord< 7 > frc::sim::DifferentialDrivetrainSim::Dynamics	(	const Vectord< 7 > &	x,
		const Eigen::Vector2d &	u )

The differential drive dynamics function.

Parameters

x	The state.
u	The input.

Returns: The state derivative with respect to time.

◆ GetCurrentDraw()

units::ampere_t frc::sim::DifferentialDrivetrainSim::GetCurrentDraw ( ) const

Returns the currently drawn current.

◆ GetGearing()

double frc::sim::DifferentialDrivetrainSim::GetGearing ( ) const

Returns the current gearing reduction of the drivetrain, as output over input.

◆ GetHeading()

Rotation2d frc::sim::DifferentialDrivetrainSim::GetHeading ( ) const

Returns the direction the robot is pointing.

Note that this angle is counterclockwise-positive, while most gyros are clockwise positive.

◆ GetLeftCurrentDraw()

units::ampere_t frc::sim::DifferentialDrivetrainSim::GetLeftCurrentDraw ( ) const

Returns the currently drawn current for the left side.

◆ GetLeftPosition()

units::meter_t frc::sim::DifferentialDrivetrainSim::GetLeftPosition ( ) const

inline

Get the left encoder position in meters.

Returns: The encoder position.

◆ GetLeftVelocity()

units::meters_per_second_t frc::sim::DifferentialDrivetrainSim::GetLeftVelocity ( ) const

inline

Get the left encoder velocity in meters per second.

Returns: The encoder velocity.

◆ GetPose()

Pose2d frc::sim::DifferentialDrivetrainSim::GetPose ( ) const

Returns the current pose.

◆ GetRightCurrentDraw()

units::ampere_t frc::sim::DifferentialDrivetrainSim::GetRightCurrentDraw ( ) const

Returns the currently drawn current for the right side.

◆ GetRightPosition()

units::meter_t frc::sim::DifferentialDrivetrainSim::GetRightPosition ( ) const

inline

Get the right encoder position in meters.

Returns: The encoder position.

◆ GetRightVelocity()

units::meters_per_second_t frc::sim::DifferentialDrivetrainSim::GetRightVelocity ( ) const

inline

Get the right encoder velocity in meters per second.

Returns: The encoder velocity.

◆ SetGearing()

void frc::sim::DifferentialDrivetrainSim::SetGearing ( double newGearing )

Sets the gearing reduction on the drivetrain.

This is commonly used for shifting drivetrains.

Parameters

newGearing The new gear ratio, as output over input.

◆ SetInputs()

void frc::sim::DifferentialDrivetrainSim::SetInputs	(	units::volt_t	leftVoltage,
		units::volt_t	rightVoltage )

Sets the applied voltage to the drivetrain.

Note that positive voltage must make that side of the drivetrain travel forward (+X).

Parameters

leftVoltage	The left voltage.
rightVoltage	The right voltage.

◆ SetPose()

void frc::sim::DifferentialDrivetrainSim::SetPose ( const frc::Pose2d & pose )

Sets the system pose.

Parameters

pose The pose.

◆ SetState()

void frc::sim::DifferentialDrivetrainSim::SetState ( const Vectord< 7 > & state )

Sets the system state.

Parameters

state The state.

◆ Update()

void frc::sim::DifferentialDrivetrainSim::Update ( units::second_t dt )

Updates the simulation.

Parameters

dt	The time that's passed since the last Update(units::second_t) call.

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

frc/simulation/DifferentialDrivetrainSim.h

Classes

Public Member Functions

Static Public Member Functions

Constructor & Destructor Documentation

◆ DifferentialDrivetrainSim() [1/2]

◆ DifferentialDrivetrainSim() [2/2]

Member Function Documentation

◆ ClampInput()

◆ CreateKitbotSim() [1/2]

◆ CreateKitbotSim() [2/2]

◆ Dynamics()

◆ GetCurrentDraw()

◆ GetGearing()

◆ GetHeading()

◆ GetLeftCurrentDraw()

◆ GetLeftPosition()

◆ GetLeftVelocity()

◆ GetPose()

◆ GetRightCurrentDraw()

◆ GetRightPosition()

◆ GetRightVelocity()

◆ SetGearing()

◆ SetInputs()

◆ SetPose()

◆ SetState()

◆ Update()