RobotArm

November 7, 2023 · View on GitHub

from tdw.add_ons.robot_arm import RobotArm

A robot with a single arm. This class includes an inverse kinematic (IK) solver that allows the robot to reach for a target position.

Class Variables

Variable	Type	Description	Value
`NON_MOVING`	float	If a joint has moved less than this many degrees (revolute or spherical) or meters (prismatic) since the previous frame, it is considered to be not moving for the purposes of determining which joints are moving.	`0.001`

Fields

static Static robot data.
dynamic Dynamic robot data.
name The name of the robot.
url The URL or filepath of the robot asset bundle.
initial_position The initial position of the robot.
initial_rotation The initial rotation of the robot.
robot_id The ID of this robot.
static Static robot data.
dynamic Dynamic robot data.
commands These commands will be appended to the commands of the next communicate() call.
initialized If True, this module has been initialized.
initial_position The initial position of the robot.
initial_rotation The initial rotation of the robot.
robot_id The ID of this robot.
static Static robot data.
dynamic Dynamic robot data.
commands These commands will be appended to the commands of the next communicate() call.
initialized If True, this module has been initialized.

Functions

init

RobotArm(name)

RobotArm(name, robot_id=0, position=None, rotation=None, source=None)

Parameter	Type	Default	Description
name	str		The name of the robot.
robot_id	int	0	The ID of the robot.
position	Dict[str, float]	None	The position of the robot. If None, defaults to `{"x": 0, "y": 0, "z": 0}`.
rotation	Dict[str, float]	None	The rotation of the robot in Euler angles (degrees). If None, defaults to `{"x": 0, "y": 0, "z": 0}`.
source	Union[RobotLibrarian, RobotRecord]	None	The source file of the robot. If None: The source will be the URL of the robot record in TDW's built-in `RobotLibrarian`. If `RobotRecord`: the source is the URL in the record. If `RobotLibrarian`: The source is the record in the provided `RobotLibrarian` that matches `name`.

get_initialization_commands

self.get_initialization_commands()

This function gets called exactly once per add-on. To re-initialize, set self.initialized = False.

Returns: A list of commands that will initialize this add-on.

joints_are_moving

self.joints_are_moving()

self.joints_are_moving(joint_ids=None)

Parameter	Type	Default	Description
joint_ids	List[int]	None	A list of joint IDs to check for movement. If `None`, check all joints for movement.

Returns: True if the joints are moving.

reset

self.reset()

self.reset(position=None, rotation=None)

Reset the robot.

Parameter	Type	Default	Description
position	Dict[str, float]	None	The position of the robot.
rotation	Dict[str, float]	None	The rotation of the robot.

on_send

self.on_send(resp)

This is called after commands are sent to the build and a response is received.

Use this function to send commands to the build on the next frame, given the resp response. Any commands in the self.commands list will be sent on the next frame.

Parameter	Type	Default	Description
resp	List[bytes]		The response from the build.

before_send

self.before_send(commands)

This is called before sending commands to the build. By default, this function doesn't do anything.

Parameter	Type	Default	Description
commands	List[dict]		The commands that are about to be sent to the build.

get_early_initialization_commands

self.get_early_initialization_commands()

This function gets called exactly once per add-on. To re-initialize, set self.initialized = False.

These commands are added to the list being sent on communicate() before any other commands, including those added by the user and by other add-ons.

Usually, you shouldn't override this function. It is useful for a small number of add-ons, such as loading screens, which should initialize before anything else.

Returns: A list of commands that will initialize this add-on.

set_joint_targets

self.set_joint_targets(targets)

Set target angles or positions for a dictionary of joints.

Parameter	Type	Default	Description
targets	Dict[int, Union[float, Dict[str, float]		A dictionary of joint targets. Key = The ID of the joint. Value = the targets. For spherical joints, this must be a Vector3 dictionary, for example `{"x": 40, "y": 0, "z": 0}` (angles in degrees). For revolute joints, this must be a float (an angle in degrees). For prismatic joints, this must be a float (a distance in meters).

add_joint_forces

self.add_joint_forces(forces)

Add torques and forces to a dictionary of joints.

Parameter	Type	Default	Description
forces	Dict[int, Union[float, Dict[str, float]		A dictionary of joint forces. Key = The ID of the joint. Value = the targets. For spherical joints, this must be a Vector3 dictionary, for example `{"x": 40, "y": 0, "z": 0}` (torques in Newtons). For revolute joints, this must be a float (a torque in Newtons). For prismatic joints, this must be a float (a force in Newtons).

stop_joints

self.stop_joints()

self.stop_joints(joint_ids=None)

Stop the joints at their current angles or positions.

Parameter	Type	Default	Description
joint_ids	List[int]	None	A list of joint IDs. If None, stop all joints.

reach_for

self.reach_for(target)

Start to reach for a target position.

Parameter	Type	Default	Description
target	POSITION		The target position. Can be a dictionary or a numpy array.