ChassisSpeeds

class wpimath.kinematics.ChassisSpeeds(vx: meters_per_second = 0, vy: meters_per_second = 0, omega: radians_per_second = 0)

Bases: pybind11_object

Represents the speed of a robot chassis. Although this struct contains similar members compared to a Twist2d, they do NOT represent the same thing. Whereas a Twist2d represents a change in pose w.r.t to the robot frame of reference, this ChassisSpeeds struct represents a velocity w.r.t to the robot frame of reference.

A strictly non-holonomic drivetrain, such as a differential drive, should never have a dy component because it can never move sideways. Holonomic drivetrains such as swerve and mecanum will often have all three components.

static fromFeet(vx: feet_per_second = 0, vy: feet_per_second = 0, omega: radians_per_second = 0) → wpimath.kinematics._kinematics.ChassisSpeeds
static fromFieldRelativeSpeeds(*args, **kwargs)

Overloaded function.

  1. fromFieldRelativeSpeeds(vx: meters_per_second, vy: meters_per_second, omega: radians_per_second, robotAngle: wpimath.geometry._geometry.Rotation2d) -> wpimath.kinematics._kinematics.ChassisSpeeds

Converts a user provided field-relative set of speeds into a robot-relative ChassisSpeeds object.

Parameters:

  • vx – The component of speed in the x direction relative to the field. Positive x is away from your alliance wall.

  • vy – The component of speed in the y direction relative to the field. Positive y is to your left when standing behind the alliance wall.

  • omega – The angular rate of the robot.

  • robotAngle – The angle of the robot as measured by a gyroscope. The robot’s angle is considered to be zero when it is facing directly away from your alliance station wall. Remember that this should be CCW positive.

Returns:

ChassisSpeeds object representing the speeds in the robot’s frame of reference.

  1. fromFieldRelativeSpeeds(fieldRelativeSpeeds: wpimath.kinematics._kinematics.ChassisSpeeds, robotAngle: wpimath.geometry._geometry.Rotation2d) -> wpimath.kinematics._kinematics.ChassisSpeeds

Converts a user provided field-relative ChassisSpeeds object into a robot-relative ChassisSpeeds object.

Parameters:

  • fieldRelativeSpeeds – The ChassisSpeeds object representing the speeds in the field frame of reference. Positive x is away from your alliance wall. Positive y is to your left when standing behind the alliance wall.

  • robotAngle – The angle of the robot as measured by a gyroscope. The robot’s angle is considered to be zero when it is facing directly away from your alliance station wall. Remember that this should be CCW positive.

Returns:

ChassisSpeeds object representing the speeds in the robot’s frame of reference.

property omega

Represents the angular velocity of the robot frame. (CCW is +)

property omega_dps
property vx

Represents forward velocity w.r.t the robot frame of reference. (Fwd is +)

property vx_fps
property vy

Represents strafe velocity w.r.t the robot frame of reference. (Left is +)

property vy_fps