Grasp

from tdw.replicant.actions.grasp import Grasp

Grasp a target object.

The action fails if the hand is already holding an object. Otherwise, the action succeeds.

When an object is grasped, it is made kinematic. Any objects contained by the object are parented to it and also made kinematic. For more information regarding containment in TDW, read this.

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Fields

• target The target object ID.

• arm The Arm value for the hand that will grasp the target object.

• angle Continuously (per communicate() call, including after this action ends), rotate the grasped object by this many degrees. If None, the grasped object will maintain its initial rotation.

• axis Continuously (per communicate() call, including after this action ends), rotate the grasped object around this axis. Options: "pitch", "yaw", "roll". If None, the grasped object will maintain its initial rotation.

• relative_to_hand If True, the object rotates relative to the hand holding it. If False, the object rotates relative to the Replicant. Ignored if angle or axis is None.

• offset Offset the object's position from the Replicant's hand by this distance.

• kinematic_objects The IDs of each kinematic object.

• status The current status of the action. By default, this is ongoing (the action isn't done).

• initialized If True, the action has initialized. If False, the action will try to send get_initialization_commands(resp) on this frame.

• done If True, this action is done and won't send any more commands.

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Functions

__init__

Grasp(target, arm, dynamic, angle, axis, relative_to_hand, offset, kinematic_objects)

Parameter	Type	Default	Description
target	int		The target object ID.
arm	Arm		The Arm value for the hand that will grasp the target object.
dynamic	ReplicantDynamic		The ReplicantDynamic data that changes per communicate() call.
angle	Optional[float]		Continuously (per communicate() call, including after this action ends), rotate the the grasped object by this many degrees relative to the hand. If None, the grasped object will maintain its initial rotation.
axis	Optional[str]		Continuously (per communicate() call, including after this action ends) rotate the grasped object around this axis relative to the hand. Options: "pitch", "yaw", "roll". If None, the grasped object will maintain its initial rotation.
relative_to_hand	bool		If True, the object rotates relative to the hand holding it. If False, the object rotates relative to the Replicant. Ignored if angle or axis is None.
offset	float		Offset the object's position from the Replicant's hand by this distance.
kinematic_objects	List[int]		The IDs of each kinematic object.

get_initialization_commands

self.get_initialization_commands(resp, static, dynamic, image_frequency)

Parameter	Type	Default	Description
resp	List[bytes]		The response from the build.
static	ReplicantStatic		The ReplicantStatic data that doesn't change after the Replicant is initialized.
dynamic	ReplicantDynamic		The ReplicantDynamic data that changes per communicate() call.
image_frequency	ImageFrequency		An ImageFrequency value describing how often image data will be captured.

Returns: A list of commands to initialize this action.

get_ongoing_commands

self.get_ongoing_commands(resp, static, dynamic)

Evaluate an action per-frame to determine whether it's done.

Parameter	Type	Default	Description
resp	List[bytes]		The response from the build.
static	ReplicantStatic		The ReplicantStatic data that doesn't change after the Replicant is initialized.
dynamic	ReplicantDynamic		The ReplicantDynamic data that changes per communicate() call.

Returns: A list of commands to send to the build to continue the action.

get_end_commands

self.get_end_commands(resp, static, dynamic, image_frequency)

Parameter	Type	Default	Description
resp	List[bytes]		The response from the build.
static	ReplicantStatic		The ReplicantStatic data that doesn't change after the Replicant is initialized.
dynamic	ReplicantDynamic		The ReplicantDynamic data that changes per communicate() call.
image_frequency	ImageFrequency		An ImageFrequency value describing how often image data will be captured.

Returns: A list of commands that must be sent to end any action.