Transform

Represents a 3D pose transformation between two coordinate frames.

Properties:

Property	Type	Description
header	Header	Transform metadata header

Read-only properties:

Property	Type	Description
translation	np.ndarray	Translation [x, y, z], unit m
rotation	np.ndarray	Quaternion [x, y, z, w]
timestamp	float	Second-precision timestamp, equivalent to header.timestamp
source_frame	str	Source frame, equivalent to header.frame_id
target_frame	str	Target frame, equivalent to constructor parameter child_frame_id
rpy	np.ndarray	Euler angles [roll, pitch, yaw], unit rad; computed from rotation

Transform

Signature:

Transform(
    translation: np.ndarray,
    rotation: np.ndarray,
    child_frame_id: str,
    header: Header | None = None,
)

Description:

Construct a Transform instance.

Parameters:

Parameter	Type	Required	Description
translation	np.ndarray	Yes	Translation [x, y, z], unit: m
rotation	np.ndarray	Yes	Quaternion [x, y, z, w]
child_frame_id	str	Yes	Target coordinate frame
header	Header | None	No	Transform metadata header; uses default Header when omitted or None

Returns:

Transform instance.

Raises:

None.

inverse

Signature:

Transform.inverse() -> Transform

Description:

Returns the inverse transform; source and target coordinate frames are swapped.

Parameters:

No parameters.

Returns:

Transform, a new inverse transform object.

Raises:

None.

to_matrix

Signature:

Transform.to_matrix() -> np.ndarray

Description:

Returns a 4x4 homogeneous transformation matrix.

Parameters:

No parameters.

Returns:

np.ndarray, shape (4, 4).

Raises:

None.

to_numpy

Signature:

Transform.to_numpy() -> dict[str, np.ndarray]

Description:

Returns a dict containing translation / rotation / rpy / matrix.

Parameters:

No parameters.

Returns:

dict[str, np.ndarray].

Raises:

None.