`phoenix6.swerve.swerve_drivetrain`#

Module Contents#

Attributes#

USE_WPILIB

phoenix6.swerve.swerve_drivetrain.USE_WPILIB = True#

class phoenix6.swerve.swerve_drivetrain.SwerveControlParameters#

Contains everything the control requests need to calculate the module state.

drivetrain_id = 0#: ID of the native drivetrain instance, used for native calls

module_locations: list[Translation2d]#: The locations of the swerve modules

max_speed: phoenix6.units.meters_per_second = 0.0#: The max speed of the robot at 12 V output, in m/s

operator_forward_direction#: The forward direction from the operator perspective

current_chassis_speed#: The current chassis speeds of the robot

current_pose#: The current pose of the robot

timestamp: phoenix6.units.second = 0.0#: The timestamp of the current control apply, in the timebase of utils.get_current_time_seconds()

update_period: phoenix6.units.second = 0.0#: The update period of control apply

class phoenix6.swerve.swerve_drivetrain.SwerveDrivetrain(drivetrain_constants: phoenix6.swerve.swerve_drivetrain_constants.SwerveDrivetrainConstants, odometry_update_frequency: phoenix6.units.hertz, modules: list[phoenix6.swerve.swerve_module_constants.SwerveModuleConstants])

class phoenix6.swerve.swerve_drivetrain.SwerveDrivetrain(drivetrain_constants: phoenix6.swerve.swerve_drivetrain_constants.SwerveDrivetrainConstants, odometry_update_frequency: phoenix6.units.hertz, odometry_standard_deviation: tuple[float, float, float], vision_standard_deviation: tuple[float, float, float], modules: list[phoenix6.swerve.swerve_module_constants.SwerveModuleConstants])

Swerve Drive class utilizing CTR Electronics’ Phoenix 6 API.

This class handles the kinematics, configuration, and odometry of a swerve drive utilizing CTR Electronics devices. We recommend using the Swerve Project Generator in Tuner X to create a template project that demonstrates how to use this class.

This class performs pose estimation internally using a separate odometry thread. Vision measurements can be added using add_vision_measurement. Other odometry APIs such as reset_pose are also available. The resulting pose estimate can be retrieved along with module states and other information using get_state. Additionally, the odometry thread synchronously provides all new state updates to a telemetry function registered with register_telemetry.

This class will construct the hardware devices internally, so the user only specifies the constants (IDs, PID gains, gear ratios, etc). Getters for these hardware devices are available.

If using the generator, the order in which modules are constructed is Front Left, Front Right, Back Left, Back Right. This means if you need the Back Left module, call get_module(2) to get the third (0-indexed) module.

class SwerveDriveState#

Plain-Old-Data class holding the state of the swerve drivetrain. This encapsulates most data that is relevant for telemetry or decision-making from the Swerve Drive.

pose#: The current pose of the robot

speeds#: The current velocity of the robot

module_states: list[SwerveModuleState]#: The current module states

module_targets: list[SwerveModuleState]#: The target module states

module_positions: list[SwerveModulePosition]#: The current module positions

raw_heading#: The raw heading of the robot, unaffected by vision updates and odometry resets

timestamp: phoenix6.units.second = 0.0#: The timestamp of the state capture, in the timebase of utils.get_current_time_seconds()

odometry_period: phoenix6.units.second = 0.0#: The measured odometry update period, in seconds

successful_daqs = 0#: Number of successful data acquisitions

failed_daqs = 0#: Number of failed data acquisitions

class OdometryThread(drivetrain: int)#

Performs swerve module updates in a separate thread to minimize latency.

Parameters:: drivetrain (int) – ID of the swerve drivetrain

start()#: Starts the odometry thread.

stop()#: Stops the odometry thread.

is_odometry_valid() → bool#

Check if the odometry is currently valid.

Returns:: True if odometry is valid
Return type:: bool

set_thread_priority(priority: int)#

Sets the odometry thread priority to a real time priority under the specified priority level

Parameters:: priority (int) – Priority level to set the odometry thread to. This is a value between 0 and 99, with 99 indicating higher priority and 0 indicating lower priority.

property odometry_thread: OdometryThread#

Gets a reference to the odometry thread.

Returns:: Odometry thread
Return type:: OdometryThread

property kinematics: wpimath.kinematics.SwerveDrive2Kinematics | wpimath.kinematics.SwerveDrive3Kinematics | wpimath.kinematics.SwerveDrive4Kinematics | wpimath.kinematics.SwerveDrive6Kinematics#

Gets a reference to the kinematics used for the drivetrain.

Returns:: Swerve kinematics
Return type:: SwerveDrive2Kinematics | SwerveDrive3Kinematics | SwerveDrive4Kinematics | SwerveDrive6Kinematics

property modules: list[phoenix6.swerve.swerve_module.SwerveModule]#

Get a reference to the full array of modules. The indexes correspond to the module described in the constructor.

Returns:: Reference to the SwerveModule array
Return type:: list[SwerveModule]

property module_locations: list[Translation2d]#

Gets the locations of the swerve modules.

Returns:: Reference to the array of swerve module locations
Return type:: list[Translation2d]

property pigeon2: phoenix6.hardware.pigeon2.Pigeon2#

Gets this drivetrain’s Pigeon 2 reference.

This should be used only to access signals and change configurations that the swerve drivetrain does not configure itself.

Returns:: This drivetrain’s Pigeon 2 reference
Return type:: Pigeon2

close()#: Closes this SwerveDrivetrain instance.

is_on_can_fd() → bool#

Gets whether the drivetrain is on a CAN FD bus.

Returns:: True if on CAN FD
Return type:: bool

get_odometry_frequency() → phoenix6.units.hertz#

Gets the target odometry update frequency.

Returns:: Target odometry update frequency
Return type:: hertz

is_odometry_valid() → bool#

Check if the odometry is currently valid.

Returns:: True if odometry is valid
Return type:: bool

set_control(request: phoenix6.swerve.requests.SwerveRequest)#

Applies the specified control request to this swerve drivetrain.

Parameters:: request (requests.SwerveRequest) – Request to apply

get_state() → SwerveDriveState#

Gets the current state of the swerve drivetrain. This includes information such as the pose estimate, module states, and chassis speeds.

Returns:: Current state of the drivetrain
Return type:: SwerveDriveState

get_state_copy() → SwerveDriveState#

Gets a copy of the current state of the swerve drivetrain. This includes information such as the pose estimate, module states, and chassis speeds.

This can be used to get a thread-safe copy of the state object.

Returns:: Copy of the current state of the drivetrain
Return type:: SwerveDriveState

register_telemetry(telemetry_function: Callable[[SwerveDriveState], None])#

It is imperative that this function is cheap, as it will be executed along with the odometry call, and if this takes a long time, it may negatively impact the odometry of this stack.

This can also be used for logging data if the function performs logging instead of telemetry. Additionally, the SwerveDriveState object can be cloned and stored for later processing.

Parameters:: telemetry_function (Callable[[SwerveDriveState], None]) – Function to call for telemetry or logging

config_neutral_mode(neutral_mode: phoenix6.signals.spn_enums.NeutralModeValue) → phoenix6.status_code.StatusCode#

Configures the neutral mode to use for all modules’ drive motors.

Parameters:: neutral_mode (NeutralModeValue) – The drive motor neutral mode
Returns:: Status code of the first failed config call, or OK if all succeeded
Return type:: StatusCode

tare_everything()#

Zero’s this swerve drive’s odometry entirely.

This will zero the entire odometry, and place the robot at 0,0

seed_field_centric()#

Resets the rotation of the robot pose to 0 from the ForwardPerspectiveValue.OPERATOR_PERSPECTIVE perspective. This makes the current orientation of the robot X forward for field-centric maneuvers.

This is equivalent to calling reset_rotation with the operator perspective rotation.

reset_pose(pose: Pose2d)#

Resets the pose of the robot. The pose should be from the ForwardPerspectiveValue.BLUE_ALLIANCE perspective.

Parameters:: pose (Pose2d) – Pose to make the current pose

reset_translation(translation: Translation2d)#

Resets the translation of the robot pose without affecting rotation. The translation should be from the ForwardPerspectiveValue.BLUE_ALLIANCE perspective.

Parameters:: translation (Translation2d) – Translation to make the current translation

reset_rotation(rotation: Rotation2d)#

Resets the rotation of the robot pose without affecting translation. The rotation should be from the ForwardPerspectiveValue.BLUE_ALLIANCE perspective.

Parameters:: rotation (Rotation2d) – Rotation to make the current rotation

set_operator_perspective_forward(field_direction: Rotation2d)#

Takes the ForwardPerspectiveValue.BLUE_ALLIANCE perpective direction and treats it as the forward direction for ForwardPerspectiveValue.OPERATOR_PERSPECTIVE.

If the operator is in the Blue Alliance Station, this should be 0 degrees. If the operator is in the Red Alliance Station, this should be 180 degrees.

This does not change the robot pose, which is in the ForwardPerspectiveValue.BLUE_ALLIANCE perspective. As a result, the robot pose may need to be reset using reset_pose.

Parameters:: field_direction (Rotation2d) – Heading indicating which direction is forward from the ForwardPerspectiveValue.BLUE_ALLIANCE perspective

get_operator_forward_direction() → Rotation2d#

Returns the ForwardPerspectiveValue.BLUE_ALLIANCE perpective direction that is treated as the forward direction for ForwardPerspectiveValue.OPERATOR_PERSPECTIVE.

If the operator is in the Blue Alliance Station, this should be 0 degrees. If the operator is in the Red Alliance Station, this should be 180 degrees.

Returns:: Heading indicating which direction is forward from the ForwardPerspectiveValue.BLUE_ALLIANCE perspective
Return type:: Rotation2d

add_vision_measurement(vision_robot_pose: Pose2d, timestamp: phoenix6.units.second, vision_measurement_std_devs: tuple[float, float, float] | None = None)#

Adds a vision measurement to the Kalman Filter. This will correct the odometry pose estimate while still accounting for measurement noise.

This method can be called as infrequently as you want, as long as you are calling SwerveDrivePoseEstimator.update every loop.

To promote stability of the pose estimate and make it robust to bad vision data, we recommend only adding vision measurements that are already within one meter or so of the current pose estimate.

Note that the vision measurement standard deviations passed into this method will continue to apply to future measurements until a subsequent call to SwerveDrivePoseEstimator.setVisionMeasurementStdDevs or this method.

Parameters:

vision_robot_pose (Pose2d) – The pose of the robot as measured by the vision camera.
timestamp (second) – The timestamp of the vision measurement in seconds. Note that you must use a timestamp with an epoch since system startup (i.e., the epoch of this timestamp is the same epoch as utils.get_current_time_seconds). This means that you should use utils.get_current_time_seconds as your time source or sync the epochs. An FPGA timestamp can be converted to the correct timebase using utils.fpga_to_current_time.
vision_measurement_std_devs (tuple[float, float, float] | None) – Standard deviations of the vision pose measurement (x position in meters, y position in meters, and heading in radians). Increase these numbers to trust the vision pose measurement less.

set_vision_measurement_std_devs(vision_measurement_std_devs: tuple[float, float, float])#

Sets the pose estimator’s trust of global measurements. This might be used to change trust in vision measurements after the autonomous period, or to change trust as distance to a vision target increases.

Parameters:: vision_measurement_std_devs (tuple[float, float, float]) – Standard deviations of the vision measurements. Increase these numbers to trust global measurements from vision less. This matrix is in the form [x, y, theta]ᵀ, with units in meters and radians.

sample_pose_at(timestamp: phoenix6.units.second) → Pose2d | None#

Return the pose at a given timestamp, if the buffer is not empty.

Parameters:: timestamp (second) – The pose’s timestamp. Note that you must use a timestamp with an epoch since system startup (i.e., the epoch of this timestamp is the same epoch as utils.get_current_time_seconds). This means that you should use utils.get_current_time_seconds as your time source in this case. An FPGA timestamp can be converted to the correct timebase using utils.fpga_to_current_time.
Returns:: The pose at the given timestamp (or None if the buffer is empty).
Return type:: Pose2d | None

get_module(index: int) → phoenix6.swerve.swerve_module.SwerveModule#

Get a reference to the module at the specified index. The index corresponds to the module described in the constructor.

Parameters:: index (int) – Which module to get
Returns:: Reference to SwerveModule
Return type:: SwerveModule

phoenix6.swerve.swerve_drivetrain#

Module Contents#

Attributes#

`phoenix6.swerve.swerve_drivetrain`#