Drive Encoder

Setup

In Constants.java, add an instance of DriveEncoderConstants. Make sure to replace the motor names and directions with the correct ones.

public static DriveEncoderConstants localizerConstants = new DriveEncoderConstants()
            .rightFrontMotorName("rf")
            .rightRearMotorName("rr")
            .leftRearMotorName("lr")
            .leftFrontMotorName("lf")
            .leftFrontEncoderDirection(Encoder.FORWARD)
            .leftRearEncoderDirection(Encoder.FORWARD)
            .rightFrontEncoderDirection(Encoder.FORWARD)
            .rightRearEncoderDirection(Encoder.FORWARD);

Then, add .driveEncoderLocalizer to createFollower:

return new FollowerBuilder(followerConstants, hardwareMap)
    .driveEncoderLocalizer(localizerConstants)
    /* other builder steps */
    .build();

Robot Dimensions

Measure your robot's wheelbase in inches.

• Length: the distance between the front and back wheels
• Width: the distance between the left and right wheels

In your DriveEncoderConstants, use .robotWidth() and .robotLength() to set the values you just measured.

Forward Tuner

We will now adjust multipliers that convert encoder ticks into real-world measurements: inches. This ensures your localizer's readings are accurate.

In the tuning OpMode, under localization, select and start the forward tuner. Then, push the robot forward 48 inches (exactly 2 field tiles). This distance is configurable if needed. Once you push the robot forward, two numbers will be displayed on telemetry:

• The distance the robot thinks it has traveled
• The multiplier; this is the number you want.

Add the multiplier to your DriveEncoderConstants by adding the following.

.forwardTicksToInches(multiplier)

Lateral Tuner

The lateral tuner is very similar to the forward tuner, except it is sideways. In the tuning OpMode, under localization, select and start the lateral tuner. Push the robot left 48 inches (exactly 2 field tiles). As with the forward tuner, this distance is configurable.

Lastly, add the multiplier to DriveEncoderConstants by adding the following line.

.strafeTicksToInches(multiplier)

Turn Tuner

The turn tuner is again, similar to both the forward tuner and lateral tuner, except it is rotational. Place the robot so it aligns to a fixed reference point (eg. edge of a field tile). In the tuning OpMode, under localization, select and start the lateral tuner. Rotate the robot counterclockwise one full rotation. As with the previous tuners, this amount is configurable.

Lastly, add the multiplier to DriveEncoderConstants by adding the following line.

.turnTicksToInches(multiplier)

Testing the localizer

Once you have completed the tuning steps, you can test your localizer as described on the localization page.

Congratulations on successfully tuning your localizer!

Troubleshooting

If you have any problems, see the troubleshooting page.