PointAxisTarget

class compas_fab.robots.PointAxisTarget

Bases: Target

Represents a point and axis target for the robot’s end-effector motion planning.

This target allows one degree of rotational freedom, enabling the end-effector to rotate around the target axis. Given a PointAxisTarget, the planner seeks a path to move the robot’s end-effector tool tip to the target point and align the tool tip’s Z axis with the specified target axis.

PointAxisTarget is suitable for tasks like drilling, milling, and 3D printing, where aligning the end-effector with a target axis is crucial, but the orientation around the axis is not important. Note that PointAxisTarget only represents a single target, for a sequence of targets, consider using PointAxisWaypoints.

The user must define (1) the target point of which the tool tip will reach and (2) the target axis where the tool tip coordinate frame (TCF)’s Z axis can rotate around. The target point and axis are defined relative to the robot’s world coordinate frame (WCF).

In addition, it’s necessary to define the tool tip coordinate frame (TCF) relative to the robot’s flange frame. This is labeled as tool_coordinate_frame. If tool_coordinate_frame is unspecified, the target point and axis will be matched with the robot’s flange frame.

For robots with multiple end effector attachment points, the FCF depends on the planning group setting in the planning request, as defined in an SRDF file or compas_fab.robots.RobotSemantics.

Attributes:

target_pointcompas.geometry.Point

The target point defined relative to the world coordinate frame (WCF).

target_z_axiscompas.geometry.Vector

The target axis is defined by the target_point and pointing towards this vector. A unitized vector is recommended. The tool tip coordinate frame (TCF)’s Z axis can rotate around this axis.

tolerance_positionfloat, optional

The tolerance for the position of the target point. If not specified, the default value from the planner is used.

tool_coordinate_framecompas.geometry.Frame, optional

The tool tip coordinate frame relative to the flange coordinate frame of the robot. If not specified, the target point is relative to the robot’s flange (T0CF) and the Z axis of the flange can rotate around the target axis.

namestr, optional

The human-readable name of the target. Defaults to ‘Point-Axis Target’.

Methods

scaled

Returns a copy of the target where the target point and tolerances are scaled.

Inherited Methods

ToString	Converts the instance to a string.
copy	Make an independent copy of the data object.
from_json	Construct an object of this type from a JSON file.
from_jsonstring	Construct an object of this type from a JSON string.
sha256	Compute a hash of the data for comparison during version control using the sha256 algorithm.
to_json	Convert an object to its native data representation and save it to a JSON file.
to_jsonstring	Convert an object to its native data representation and save it to a JSON string.
validate_data	Validate the data against the object's data schema.