A change in distance along a 2D arc since the last pose update. More...

#include <frc/geometry/Twist2d.h>

Public Member Functions
constexpr Transform2d	Exp () const
	Obtain a new Transform2d from a (constant curvature) velocity.

constexpr bool	operator== (const Twist2d &other) const
	Checks equality between this Twist2d and another object.

constexpr Twist2d	operator* (double factor) const
	Scale this by a given factor.

Public Attributes
units::meter_t	dx = 0_m
	Linear "dx" component.

units::meter_t	dy = 0_m
	Linear "dy" component.

units::radian_t	dtheta = 0_rad
	Angular "dtheta" component (radians)

Detailed Description

A change in distance along a 2D arc since the last pose update.

We can use ideas from differential calculus to create new Pose2ds from a Twist2d and vice versa.

A Twist can be used to represent a difference between two poses.

Member Function Documentation

◆ Exp()

Transform2d frc::Twist2d::Exp ( ) const

constexpr

Obtain a new Transform2d from a (constant curvature) velocity.

See "https://file.tavsys.net/control/controls-engineering-in-frc.pdf" Controls Engineering in the FIRST Robotics Competition section 10.2 "Pose exponential" for a derivation.

The twist is a change in pose in the robot's coordinate frame since the previous pose update. When the user runs Exp() on the twist, the user will receive the pose delta.

"Exp" represents the pose exponential, which is solving a differential equation moving the pose forward in time.

Returns: The pose delta of the robot.

◆ operator*()

Twist2d frc::Twist2d::operator* ( double factor ) const

inlineconstexpr

Scale this by a given factor.

Parameters

factor The factor by which to scale.

Returns: The scaled Twist2d.

◆ operator==()

bool frc::Twist2d::operator== ( const Twist2d & other ) const

inlineconstexpr

Checks equality between this Twist2d and another object.

Parameters

other The other object.

Returns: Whether the two objects are equal.

Member Data Documentation

◆ dtheta

units::radian_t frc::Twist2d::dtheta = 0_rad

Angular "dtheta" component (radians)

◆ dx

units::meter_t frc::Twist2d::dx = 0_m

Linear "dx" component.

◆ dy

units::meter_t frc::Twist2d::dy = 0_m

Linear "dy" component.

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

frc/geometry/Twist2d.h

Public Member Functions

Public Attributes