Class AnalogGyro

  • All Implemented Interfaces:
    Gyro, PIDSource, Sendable, AutoCloseable

    public class AnalogGyro
    extends GyroBase
    implements Gyro, PIDSource, Sendable
    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 class is for gyro sensors that connect to an analog input.

    • Constructor Detail

      • AnalogGyro

        public AnalogGyro​(int channel)
        Gyro constructor using the channel number.
        Parameters:
        channel - The analog channel the gyro is connected to. Gyros can only be used on on-board channels 0-1.
      • AnalogGyro

        public AnalogGyro​(AnalogInput channel)
        Gyro constructor with a precreated analog channel object. Use this constructor when the analog channel needs to be shared.
        Parameters:
        channel - The AnalogInput object that the gyro is connected to. Gyros can only be used on on-board channels 0-1.
      • AnalogGyro

        public AnalogGyro​(int channel,
                          int center,
                          double offset)
        Gyro constructor using the channel number along 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 channels 0-1.
        center - Preset uncalibrated value to use as the accumulator center value.
        offset - Preset uncalibrated value to use as the gyro offset.
      • AnalogGyro

        public AnalogGyro​(AnalogInput channel,
                          int center,
                          double offset)
        Gyro constructor with a precreated analog channel object along 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 channels 0-1.
        center - Preset uncalibrated value to use as the accumulator center value.
        offset - Preset uncalibrated value to use as the gyro offset.
    • Method Detail

      • initGyro

        public void initGyro()
        Initialize the gyro. Calibration is handled by calibrate().
      • calibrate

        public void calibrate()
        Description copied from interface: Gyro
        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.
        Specified by:
        calibrate in interface Gyro
      • reset

        public void reset()
        Description copied from interface: Gyro
        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.
        Specified by:
        reset in interface Gyro
      • close

        public void close()
        Delete (free) the accumulator and the analog components used for the gyro.
        Specified by:
        close in interface AutoCloseable
        Overrides:
        close in class SendableBase
      • getAngle

        public double getAngle()
        Description copied from interface: Gyro
        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 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 clockwise when looked at from the top. It needs to follow NED axis conventions in order to work properly with dependent control loops.

        This heading is based on integration of the returned rate from the gyro.

        Specified by:
        getAngle in interface Gyro
        Returns:
        the current heading of the robot in degrees.
      • getRate

        public double getRate()
        Description copied from interface: Gyro
        Return the rate of rotation of the gyro.

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

        The rate is expected to be positive as the gyro turns clockwise when looked at from the top. It needs to follow NED axis conventions in order to work properly with dependent control loops.

        Specified by:
        getRate in interface Gyro
        Returns:
        the current rate in degrees per second
      • getOffset

        public double getOffset()
        Return the gyro offset value set during calibration to use as a future preset.
        Returns:
        the current offset value
      • getCenter

        public int getCenter()
        Return the gyro center value set during calibration to use as a future preset.
        Returns:
        the current center value
      • setSensitivity

        public void 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.