Class SwerveAlignment

java.lang.Object

frc.robot.subsystems.swerve.SwerveAlignment

public class SwerveAlignment
extends Object

Publishes the raw per-module CANcoder data that swerve alignment needs.

CTRE's swerve telemetry only reports module angles after the magnet offset has been applied, so there is no way to recover the number that belongs in SwerveConfig.configEncoderOffsets(...) from a log or a dashboard. This class fills that gap: it publishes each module's offset-applied position, the magnet offset actually programmed into the device, and the difference between them, which is the "Absolute Position No Offset" value Phoenix Tuner X shows.

The Swerve Align page of the robot app (src/main/deploy/app/pages/swerve-align) subscribes to these keys over NetworkTables.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	KEY_PREFIX	NetworkTables/DogLog key prefix for everything this class publishes.
static final String[]	MODULE_NAMES	Module names, in the order SwerveConfig.getModules() returns them.

Constructor Summary

Constructors

Constructor	Description
SwerveAlignment(SwerveModule<?,?,CANcoder>[] modules, SwerveConfig config)	Creates the alignment publisher.

Method Summary

Modifier and Type	Method	Description
void	log()	Refreshes and publishes the alignment data.
static double	wrapRotations(double rotations)	Wraps a rotation count into [-0.5, 0.5), matching how CTRE reports CANcoder absolute position.

Methods inherited from class Object

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

Field Details

KEY_PREFIX

public static final String KEY_PREFIX

NetworkTables/DogLog key prefix for everything this class publishes.

See Also:

• Constant Field Values

MODULE_NAMES

public static final String[] MODULE_NAMES

Module names, in the order SwerveConfig.getModules() returns them.

Constructor Details

SwerveAlignment

public SwerveAlignment(SwerveModule<?,?,CANcoder>[] modules,
 SwerveConfig config)

Creates the alignment publisher.

Construct this after optimizeBusUtilization() so the update frequencies it requests are not immediately thrown away.

Parameters:

modules - the drivetrain's modules, in SwerveConfig.getModules() order

config - the swerve config the modules were built from

Method Details

log

public void log()

Refreshes and publishes the alignment data. Safe to call every robot loop.

Only publishes while the robot is disabled. Alignment is a pit procedure done on blocks with the robot disabled. These are 32 keys at 20 Hz, about 77 records a second, going into a log that already overran DogLog's queue and dropped data during the 2026-09-05 17:10 session. There is nothing to learn from them while the robot is driving.

wrapRotations

public static double wrapRotations(double rotations)

Wraps a rotation count into [-0.5, 0.5), matching how CTRE reports CANcoder absolute position.

Parameters:

rotations - the value to wrap

Returns:

the equivalent value in [-0.5, 0.5)