Update

SUMMARY

update sets a new transform between an existing frame and its parent, given as a 4x4 matrix or a 6/7-element pose.

UNITS

transform's position component is in meters, whether passed as a (4, 4) matrix (rot_type="mat") or a pose list. Rotation is in degrees ("deg"), radians ("rad"), or unitless ("quat").

The Skill

tree.update("camera", [0, 0, 1.2, 0, 0, 0], rot_type="deg")

Example

Before

The camera frame at its original pose in the tree.

After

The same frame after update sets its new transform to its parent.

The Code

"""
Example of TransformTree.update.
"""

from loguru import logger
import time

from telekinesis.tf import tftree


def main():
    """
    Update the transform of an existing frame in the tree.
    """
    tree = tftree.TransformTree("world")
    tree.add("world", "camera", [0, 0, 1, 0, 0, 0], rot_type="deg")
    tree.visualize_rerun()
    logger.info(f"camera pose before update: {tree.lookup_transform('world', 'camera', rot_type='deg')}")

    time.sleep(3)
    tree.update("camera", [-0.5, -0.5, 1.5, 0, 0, 0], rot_type="deg")
    tree.visualize_rerun()
    logger.info(f"camera pose after update: {tree.lookup_transform('world', 'camera', rot_type='deg')}")

if __name__ == "__main__":
    main()

Parameter Configuration

Parameter	Type	Default	Description
source_name	str	required	The name of the frame whose transform to its parent is updated.
transform	np.ndarray | list	required	The new transform to the frame's parent: a (4, 4) matrix, or a 6-element (deg/rad) or 7-element (quat) pose.
rot_type	str	"deg"	One of "deg", "rad", "quat", "mat". Note this default differs from add's, which defaults to "mat".

Raises

Exception	Condition
TypeError	source_name is not a string.
ValueError	transform is not a (4, 4) np.ndarray or a 6/7-element list.
ValueError	rot_type is not one of "deg", "rad", "quat", "mat".
ValueError	No frame named source_name exists in the tree.