Package frc.robot.subsystems.swerve.util

Class TuningCommands

java.lang.Object

frc.robot.subsystems.swerve.util.TuningCommands

public final class TuningCommands
extends Object

Collection of command factories used for drivetrain tuning and characterization.

This class provides reusable command sequences for empirically determining drivetrain parameters such as feedforward gains and effective wheel radius. These commands are intended to be run manually during calibration and development, not during normal match operation.

This class is non-instantiable and only contains static factory methods.

Method Summary

Modifier and Type	Method	Description
static Command	feedforwardCharacterization(Swerve swerve, DoubleConsumer runCharacterization, DoubleSupplier getFFCharacterizationVelocity)	Creates a command to characterize drivetrain feedforward constants.
static Command	wheelRadiusCharacterization(Swerve swerve, Consumer<ChassisSpeeds> setModuleStates, Supplier<double[]> getWheelRadiusCharacterizationPositions, Supplier<Rotation2d> gyroYaw)	Creates a command to characterize the effective wheel radius of the drivetrain.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

feedforwardCharacterization

public static Command feedforwardCharacterization(Swerve swerve,
 DoubleConsumer runCharacterization,
 DoubleSupplier getFFCharacterizationVelocity)

Creates a command to characterize drivetrain feedforward constants.

This routine performs a quasi-static ramp test by slowly increasing applied voltage while measuring the resulting drivetrain velocity. The collected data is fit using linear regression to estimate:

• kS - static friction voltage
• kV - velocity-proportional voltage

The characterization process consists of:

1. Orient all modules to face forward
2. Holding zero output to allow modules to fully orient
3. Linearly ramping voltage at a fixed rate
4. Recording velocity and voltage samples each loop

When the command is cancelled, the collected samples are fit and the resulting constants are printed to the console and logged.

This routine should be run on flat carpet with minimal disturbances.

Parameters:

swerve - the swerve subsystem being characterized

runCharacterization - consumer that applies a raw voltage command to the drivetrain

getFFCharacterizationVelocity - supplier that returns the current drivetrain velocity for sampling

Returns:

a command that performs feedforward characterization

wheelRadiusCharacterization

public static Command wheelRadiusCharacterization(Swerve swerve,
 Consumer<ChassisSpeeds> setModuleStates,
 Supplier<double[]> getWheelRadiusCharacterizationPositions,
 Supplier<Rotation2d> gyroYaw)

Creates a command to characterize the effective wheel radius of the drivetrain.

This routine estimates wheel radius by rotating the robot in place and comparing the integrated gyro rotation against the average wheel travel. The wheel radius is computed using the relationship:

 wheelRadius = (robotRotation * driveBaseRadius) / wheelTravel
 

The command runs two sequences in parallel:

• A drive sequence that smoothly accelerates rotational speed
• A measurement sequence that integrates gyro rotation and wheel deltas

Intermediate values and the computed wheel radius are logged continuously for validation and offline analysis.

This routine assumes:

• Accurate gyro measurements
• Consistent wheel traction during rotation
• Correct drivetrain geometry constants

Parameters:

swerve - the swerve subsystem being characterized

setModuleStates - consumer used to command rotational chassis speeds

getWheelRadiusCharacterizationPositions - supplier of wheel position measurements

gyroYaw - supplier of the current robot yaw angle

Returns:

a command that performs wheel radius characterization