Package frc.team4373.swerve

Class SwerveDrivetrain

  • All Implemented Interfaces:
    edu.wpi.first.wpilibj.Sendable, java.lang.AutoCloseable
    public abstract class SwerveDrivetrain
extends edu.wpi.first.wpilibj.command.Subsystem
    A programmatic representation of a swerve drivetrain.

    Requirements:

    • The robot must be rectangular.
    • The robot must be rectangular.
    • The motors must use CTRE TalonSRX motor controllers.
    • The robot must have a Pigeon IMU.
    • The motor controllers and Pigeon must be connected over the CAN bus.
    • The motor controlllers must have encoders connected.

    • Constructor Detail

      • SwerveDrivetrain

        protected SwerveDrivetrain​(SwerveConfig config)
        Creates a new SwerveDrivetrain subclass instance with the given configuration.
        Parameters:
        config - the configuration for the new SwerveDrivetrain.

    • Method Detail

      • stop

        public void stop()
        Stops the robot (i.e., sets outputs of all motors of all wheels to zero).

      • drive

        public void drive​(double rotation,
                  double x,
                  double y)
        Drives using the transform for the given parameters.
        Parameters:
        rotation - the joystick rotation, in degrees.
        x - the x-coordinate, -1 to 1.
        y - the y-coordinate, -1 to 1.

      • brake

        public void brake()
        Sets the wheels to the configured brake configuration if any is selected.

      • setWheelsPID

        public void setWheelsPID​(WheelVector.VectorSet vectors)
        Sets velocity vectors to the four SwerveWheels with PID setpoints for both speed and angle.
        Parameters:
        vectors - the four vectors ordered right1, left1, left2, right2.

      • setWheelsPercOut

        public void setWheelsPercOut​(WheelVector.VectorSet vectors)
        Sets vectors to the SwerveWheels with a PID setpoint for angle and % output for speed.
        Parameters:
        vectors - the four vectors ordered right1, left1, left2, right2.

      • getAngle

        public double getAngle()
        Returns the current angle relative to the starting position (mod 360).
        Returns:
        the current angle relative to the starting position on the interval [0, 360).

      • getPigeonYawRaw

        public double getPigeonYawRaw()
        Returns the raw Pigeon yaw value.
        Returns:
        Pigeon yaw value.

      • getPercentOutput

        public double getPercentOutput​(SwerveDrivetrain.WheelID wheelID)
        Gets the percent output of the specified SwerveWheel.
        Parameters:
        wheelID - the ID of the wheel.
        Returns:
        the wheel's percent output, [-1, 1].

      • getDriveMotorPosition

        public double getDriveMotorPosition​(SwerveDrivetrain.WheelID wheelID)
        Gets the current position of the drive motor.
        Parameters:
        wheelID - the ID of the wheel whose position to fetch.
        Returns:
        the current position in encoder units.

      • getAverageDriveMotorPosition

        public double getAverageDriveMotorPosition()
        Gets the average of the drive motor positions.
        Returns:
        average of drive position in encoder units.

      • getDriveMotorVelocity

        public double getDriveMotorVelocity​(SwerveDrivetrain.WheelID wheelID)
        Gets the velocity of the drive motor for the specified wheel.
        Parameters:
        wheelID - the ID of the wheel whose drive velocity to fetch.
        Returns:
        the wheel's drive velocity in encoder units.

      • getRotatorMotorPosition

        public double getRotatorMotorPosition​(SwerveDrivetrain.WheelID wheelID)
        Gets the position of the rotator motor for the specified wheel. Since the rotator is a mag encoder, this is an absolute position.
        Parameters:
        wheelID - the ID of the wheel whose rotator position to fetch.
        Returns:
        the wheel's absolute rotator position in encoder units.

      • getRotatorMotorVelocity

        public double getRotatorMotorVelocity​(SwerveDrivetrain.WheelID wheelID)
        Gets the velocity of the rotator motor for the specified wheel.
        Parameters:
        wheelID - the ID of the wheel whose rotator velocity to fetch.
        Returns:
        the wheel's rotator velocity in encoder units.

      • setMaxWheelAcceleration

        public void setMaxWheelAcceleration​(double maxAccel)
        Sets the max acceleration for each wheel.
        Parameters:
        maxAccel - the maximum acceleration.

      • modularizeEncoders

        public void modularizeEncoders()
        Resets the encoders to within [-4095, 4095] Call this method in `robotInit` to (almost) eliminate the possibility of accumulator rollover during one power cycle.

      • resetEncoder

        public void resetEncoder​(SwerveDrivetrain.WheelID wheelID)
        Resets the position of the rotator encoder of the given wheel.

        This function should NEVER regularly be called. It should be called once per mechanical change, with all wheels facing forward.

        Parameters:
        wheelID - the wheel whose encoder should be reset.

      • resetPigeonYaw

        public void resetPigeonYaw()
        Resets the pigeon's yaw to consider the current orientation field-forward (zero degrees).

      • setPigeonYaw

        public void setPigeonYaw​(double angle)
        Sets the pigeon's yaw to be a given value at the current position.
        Parameters:
        angle - the value, in degrees, that the pigeon should have at the current position..