Package edu.wpi.first.math.kinematics

Interface Kinematics<S,P>

Type Parameters:
S - The type of the wheel speeds.
P - The type of the wheel positions.
All Superinterfaces:
Interpolator<P>
All Known Implementing Classes:
DifferentialDriveKinematics, MecanumDriveKinematics, SwerveDriveKinematics
public interface Kinematics<S,P> extends Interpolator<P>
Helper class that converts a chassis velocity (dx and dtheta components) into wheel speeds. Robot code should not use this directly- Instead, use the particular type for your drivetrain (e.g., DifferentialDriveKinematics).

  • Method Summary

    Modifier and Type
    Method
    Description
    P
    copy(P positions)
    Returns a copy of the wheel positions object.
    void
    copyInto(P positions, P output)
    Copies the value of the wheel positions object into the output.
    ChassisSpeeds
    toChassisSpeeds(S wheelSpeeds)
    Performs forward kinematics to return the resulting chassis speed from the wheel speeds.
    Twist2d
    toTwist2d(P start, P end)
    Performs forward kinematics to return the resulting Twist2d from the given change in wheel positions.
    S
    toWheelSpeeds(ChassisSpeeds chassisSpeeds)
    Performs inverse kinematics to return the wheel speeds from a desired chassis velocity.

    Methods inherited from interface edu.wpi.first.math.interpolation.Interpolator

    interpolate

  • Method Details

    • toChassisSpeeds

      ChassisSpeeds toChassisSpeeds(S wheelSpeeds)
      Performs forward kinematics to return the resulting chassis speed from the wheel speeds. This method is often used for odometry -- determining the robot's position on the field using data from the real-world speed of each wheel on the robot.
      Parameters:
      wheelSpeeds - The speeds of the wheels.
      Returns:
      The chassis speed.

    • toWheelSpeeds

      S toWheelSpeeds(ChassisSpeeds chassisSpeeds)
      Performs inverse kinematics to return the wheel speeds from a desired chassis velocity. This method is often used to convert joystick values into wheel speeds.
      Parameters:
      chassisSpeeds - The desired chassis speed.
      Returns:
      The wheel speeds.

    • toTwist2d

      Twist2d toTwist2d(P start, P end)
      Performs forward kinematics to return the resulting Twist2d from the given change in wheel positions. This method is often used for odometry -- determining the robot's position on the field using changes in the distance driven by each wheel on the robot.
      Parameters:
      start - The starting distances driven by the wheels.
      end - The ending distances driven by the wheels.
      Returns:
      The resulting Twist2d in the robot's movement.

    • copy

      P copy(P positions)
      Returns a copy of the wheel positions object.
      Parameters:
      positions - The wheel positions object to copy.
      Returns:
      A copy.

    • copyInto

      void copyInto(P positions, P output)
      Copies the value of the wheel positions object into the output.
      Parameters:
      positions - The wheel positions object to copy. Will not be modified.
      output - The output variable of the copy operation. Will have the same value as the positions object after the call.