Use a rate gyro to return the robots heading relative to a starting position. More...

#include <frc/AnalogGyro.h>

Inheritance diagram for frc::AnalogGyro:

Public Member Functions
	AnalogGyro (int channel)
	Gyro constructor using the Analog Input channel number. More...

	AnalogGyro (AnalogInput *channel)
	Gyro constructor with a precreated AnalogInput object. More...

	AnalogGyro (std::shared_ptr< AnalogInput > channel)
	Gyro constructor with a precreated AnalogInput object. More...

	AnalogGyro (int channel, int center, double offset)
	Gyro constructor using the Analog Input channel number with parameters for presetting the center and offset values. More...

	AnalogGyro (std::shared_ptr< AnalogInput > channel, int center, double offset)
	Gyro constructor with a precreated AnalogInput object and calibrated parameters. More...

	~AnalogGyro () override

	AnalogGyro (AnalogGyro &&rhs)=default

AnalogGyro &	operator= (AnalogGyro &&rhs)=default

double	GetAngle () const
	Return the actual angle in degrees that the robot is currently facing. More...

double	GetRate () const
	Return the rate of rotation of the gyro. More...

virtual int	GetCenter () const
	Return the gyro center value. More...

virtual double	GetOffset () const
	Return the gyro offset value. More...

void	SetSensitivity (double voltsPerDegreePerSecond)
	Set the gyro sensitivity. More...

void	SetDeadband (double volts)
	Set the size of the neutral zone. More...

void	Reset ()
	Reset the gyro. More...

void	InitGyro ()
	Initialize the gyro. More...

void	Calibrate ()
	Calibrate the gyro by running for a number of samples and computing the center value. More...

Rotation2d	GetRotation2d () const
	Return the heading of the robot as a Rotation2d. More...

std::shared_ptr< AnalogInput >	GetAnalogInput () const
	Gets the analog input for the gyro. More...

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

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

virtual void	InitSendable (SendableBuilder &builder)=0
	Initializes this Sendable object. More...

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

	SendableHelper (SendableHelper &&rhs)

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

SendableHelper &	operator= (SendableHelper &&rhs)

Static Public Attributes
static constexpr int	kOversampleBits = 10

static constexpr int	kAverageBits = 0

static constexpr double	kSamplesPerSecond = 50.0

static constexpr double	kCalibrationSampleTime = 5.0

static constexpr double	kDefaultVoltsPerDegreePerSecond = 0.007

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

	~SendableHelper ()

Detailed Description

Use a rate gyro to return the robots heading relative to a starting position.

The Gyro class tracks the robots heading based on the starting position. As the robot rotates the new heading is computed by integrating the rate of rotation returned by the sensor. When the class is instantiated, it does a short calibration routine where it samples the gyro while at rest to determine the default offset. This is subtracted from each sample to determine the heading. This gyro class must be used with a channel that is assigned one of the Analog accumulators from the FPGA. See AnalogInput for the current accumulator assignments.

This class is for gyro sensors that connect to an analog input.

Constructor & Destructor Documentation

◆ AnalogGyro() [1/6]

frc::AnalogGyro::AnalogGyro ( int channel )

explicit

Gyro constructor using the Analog Input channel number.

Parameters

channel The analog channel the gyro is connected to. Gyros can only be used on on-board Analog Inputs 0-1.

◆ AnalogGyro() [2/6]

frc::AnalogGyro::AnalogGyro ( AnalogInput * channel )

explicit

Gyro constructor with a precreated AnalogInput object.

Use this constructor when the analog channel needs to be shared. This object will not clean up the AnalogInput object when using this constructor.

Gyros can only be used on on-board channels 0-1.

Parameters

channel A pointer to the AnalogInput object that the gyro is connected to.

◆ AnalogGyro() [3/6]

frc::AnalogGyro::AnalogGyro ( std::shared_ptr< AnalogInput > channel )

explicit

Gyro constructor with a precreated AnalogInput object.

Use this constructor when the analog channel needs to be shared. This object will not clean up the AnalogInput object when using this constructor.

Parameters

channel A pointer to the AnalogInput object that the gyro is connected to.

◆ AnalogGyro() [4/6]

frc::AnalogGyro::AnalogGyro	(	int	channel,
		int	center,
		double	offset
	)

Gyro constructor using the Analog Input channel number with parameters for presetting the center and offset values.

Bypasses calibration.

Parameters

channel	The analog channel the gyro is connected to. Gyros can only be used on on-board Analog Inputs 0-1.
center	Preset uncalibrated value to use as the accumulator center value.
offset	Preset uncalibrated value to use as the gyro offset.

◆ AnalogGyro() [5/6]

frc::AnalogGyro::AnalogGyro	(	std::shared_ptr< AnalogInput >	channel,
		int	center,
		double	offset
	)

Gyro constructor with a precreated AnalogInput object and calibrated parameters.

Use this constructor when the analog channel needs to be shared. This object will not clean up the AnalogInput object when using this constructor.

Parameters

channel	A pointer to the AnalogInput object that the gyro is connected to.
center	Preset uncalibrated value to use as the accumulator center value.
offset	Preset uncalibrated value to use as the gyro offset.

◆ ~AnalogGyro()

frc::AnalogGyro::~AnalogGyro ( )

override

◆ AnalogGyro() [6/6]

frc::AnalogGyro::AnalogGyro ( AnalogGyro && rhs )

default

Member Function Documentation

◆ Calibrate()

void frc::AnalogGyro::Calibrate ( )

Calibrate the gyro by running for a number of samples and computing the center value.

Then use the center value as the Accumulator center value for subsequent measurements.

It's important to make sure that the robot is not moving while the centering calculations are in progress, this is typically done when the robot is first turned on while it's sitting at rest before the competition starts.

◆ GetAnalogInput()

std::shared_ptr< AnalogInput > frc::AnalogGyro::GetAnalogInput ( ) const

Gets the analog input for the gyro.

Returns: AnalogInput

◆ GetAngle()

double frc::AnalogGyro::GetAngle ( ) const

Return the actual angle in degrees that the robot is currently facing.

The angle is based on the current accumulator value corrected by the oversampling rate, the gyro type and the A/D calibration values. The angle is continuous, that is it will continue from 360->361 degrees. This allows algorithms that wouldn't want to see a discontinuity in the gyro output as it sweeps from 360 to 0 on the second time around.

Returns: The current heading of the robot in degrees. This heading is based on integration of the returned rate from the gyro.

◆ GetCenter()

virtual int frc::AnalogGyro::GetCenter ( ) const

virtual

Return the gyro center value.

If run after calibration, the center value can be used as a preset later.

Returns: the current center value

◆ GetOffset()

virtual double frc::AnalogGyro::GetOffset ( ) const

virtual

Return the gyro offset value.

If run after calibration, the offset value can be used as a preset later.

Returns: the current offset value

◆ GetRate()

double frc::AnalogGyro::GetRate ( ) const

Return the rate of rotation of the gyro.

The rate is based on the most recent reading of the gyro analog value

Returns: the current rate in degrees per second

◆ GetRotation2d()

Rotation2d frc::AnalogGyro::GetRotation2d ( ) const

Return the heading of the robot as a Rotation2d.

The angle is continuous, that is it will continue from 360 to 361 degrees. This allows algorithms that wouldn't want to see a discontinuity in the gyro output as it sweeps past from 360 to 0 on the second time around.

The angle is expected to increase as the gyro turns counterclockwise when looked at from the top. It needs to follow the NWU axis convention.

Returns: the current heading of the robot as a Rotation2d. This heading is based on integration of the returned rate from the gyro.

◆ InitGyro()

void frc::AnalogGyro::InitGyro ( )

Initialize the gyro.

Calibration is handled by Calibrate().

◆ InitSendable()

void frc::AnalogGyro::InitSendable ( wpi::SendableBuilder & builder )

overridevirtual

Initializes this Sendable object.

Parameters

builder sendable builder

Implements wpi::Sendable.

◆ operator=()

AnalogGyro & frc::AnalogGyro::operator= ( AnalogGyro && rhs )

default

◆ Reset()

void frc::AnalogGyro::Reset ( )

Reset the gyro.

Resets the gyro to a heading of zero. This can be used if there is significant drift in the gyro and it needs to be recalibrated after it has been running.

◆ SetDeadband()

void frc::AnalogGyro::SetDeadband ( double volts )

Set the size of the neutral zone.

Any voltage from the gyro less than this amount from the center is considered stationary. Setting a deadband will decrease the amount of drift when the gyro isn't rotating, but will make it less accurate.

Parameters

volts The size of the deadband in volts

◆ SetSensitivity()

void frc::AnalogGyro::SetSensitivity ( double voltsPerDegreePerSecond )

Set the gyro sensitivity.

This takes the number of volts/degree/second sensitivity of the gyro and uses it in subsequent calculations to allow the code to work with multiple gyros. This value is typically found in the gyro datasheet.

Parameters

voltsPerDegreePerSecond The sensitivity in Volts/degree/second

Member Data Documentation

◆ kAverageBits

constexpr int frc::AnalogGyro::kAverageBits = 0

staticconstexpr

◆ kCalibrationSampleTime

constexpr double frc::AnalogGyro::kCalibrationSampleTime = 5.0

staticconstexpr

◆ kDefaultVoltsPerDegreePerSecond

constexpr double frc::AnalogGyro::kDefaultVoltsPerDegreePerSecond = 0.007

staticconstexpr

◆ kOversampleBits

constexpr int frc::AnalogGyro::kOversampleBits = 10

staticconstexpr

◆ kSamplesPerSecond

constexpr double frc::AnalogGyro::kSamplesPerSecond = 50.0

staticconstexpr

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

frc/AnalogGyro.h

Public Member Functions

Static Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ AnalogGyro() [1/6]

◆ AnalogGyro() [2/6]

◆ AnalogGyro() [3/6]

◆ AnalogGyro() [4/6]

◆ AnalogGyro() [5/6]

◆ ~AnalogGyro()

◆ AnalogGyro() [6/6]

Member Function Documentation

◆ Calibrate()

◆ GetAnalogInput()

◆ GetAngle()

◆ GetCenter()

◆ GetOffset()

◆ GetRate()

◆ GetRotation2d()

◆ InitGyro()

◆ InitSendable()

◆ operator=()

◆ Reset()

◆ SetDeadband()

◆ SetSensitivity()

Member Data Documentation

◆ kAverageBits

◆ kCalibrationSampleTime

◆ kDefaultVoltsPerDegreePerSecond

◆ kOversampleBits

◆ kSamplesPerSecond