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The Flexiv Rizon Arm as GRID drives it — what this robot actually implements, with the signatures it actually accepts. connect("<name>") returns a RemoteRobot. Its attributes are the methods and subcomponents below, and every call runs on the robot; the driver behind it is FlexivRizon. Connecting neither starts nor moves the robot — it attaches to one that is already up. A method that fails on the robot arrives as RuntimeError naming the original error in its message. The client packages this page uses are preinstalled in every GRID session workspace and in the Python environment the GRID CLI prepares when you run a program with skill run; there is nothing to install.

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Methods on the robot

Called as robot.<method>(...).

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addNamedPose()

Signature
Define a pose_name:joint_angles pair in the dictionary of named poses (overriding any existing pair).
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required
Name of the pose to define
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required
List of joint angles in radians
Raises: ValueError: If the length of joint_angles list does match the length of other named poses

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endFreeDrive()

Signature
Exit free-drive mode and return to position control. The arm is no longer movable by hand and again responds to position-control commands such as moveToPose and setJointAngles.

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getEndEffectorForce()

Signature
Measured finger force in Newtons. Positive: opening force, negative: closing force. Reads 0 if the enabled gripper has no force sensing capability [N]

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getEndEffectorGraspDetected()

Signature
Returns True if the gripper is grasping an object.

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getEndEffectorIsMoving()

Signature
Returns True if the gripper is currently moving.

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getEndEffectorPose()

Signature

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getEndEffectorWidth()

Signature
Get the current gripper width in meters.

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getImage()

Signature
Return the image of camera. Which camera a no-argument call reads is decided by cardinality alone — no robot, config, or class declares a default. A robot with exactly one camera needs no name; a robot with several requires one, so adding a second camera never silently changes which one a bare getImage() returns.
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str
default:"''"
Name of the camera to get image from — either a directly attached camera’s name or a /-separated path through subcomponents to a nested one (left_arm/wrist). May be omitted when the robot has exactly one camera.
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Forwarded to the underlying sensor’s getImage. Lets callers pass camera-specific options (e.g. image_type="depth", compressed=False) without the base class having to enumerate them.
Returns: Image: The captured image. Raises: RuntimeError: If no cameras are configured, or the name is omitted on a robot with more than one camera; the message lists every configured camera path. KeyError: If camera_name is given but names no camera on this robot.

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getJointAngles()

Signature
Get current seven joint angles in radians. Returns: Current seven joint angles in radians, with base joint first

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getJointVelocities()

Signature
Get current seven joint velocities in radians/second. Returns: Current seven joint velocities in radians/second, with base joint first

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getLidarPointCloud()

Signature
Get a point cloud from the named LiDAR sensor.
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str
default:"''"
Name of the lidar. If empty, uses the first available lidar.
Returns: Optional[PointCloud]: The point cloud, or None if lidar not found

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getNamedPose()

Signature
Get the list of joint angles corresponding to a named pose.
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required
Name of the pose to get (case-insensitive)
Returns: list: Joint angles (radians) of the named pose, or None if the named pose does not exist

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getOrientation()

Signature
Get the current end effector orientation with respect to the robot base Returns: Current orientation of the robot in world coordinates, or None if orientation is unavailable

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getPose()

Signature
Get the current end effector pose (position and orientation) in the robot base frame. Returns: Current Tool-Center-Point (TCP) pose.

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getPosition()

Signature
Get the current end effector position with respect to the robot base (meters). Returns: Current position of the robot in world coordinates, or None if position is unavailable

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getState()

Signature
Get a live state snapshot of this component’s tree. Recursive walk owned by the base class, following the lifecycle template: each class contributes only the protected local hook _local_state, and the walk composes the per-component results into one nested mapping. Subclasses must not replace this method — per-component state belongs in _local_state. With no keys, returns this component’s local state merged with one nested node per subcomponent name — the tree structure is the nesting itself, and the names mirror subcomponents (and therefore serialize() and edge introspection): a two-arm rig returns &#123;"left_arm": &#123;"joint_positions": ...&#125;, "right_arm": &#123;...&#125;&#125;, and a leaf component returns its local state alone. A component whose state could not be read (dead telemetry, not yet started, already shut down) carries an "error" entry — &#123;"error": "&lt;ExceptionType>: &lt;message>"&#125;, with its children still nested alongside — instead of its state keys. Errors are contained per node: one failing component never loses the rest of the snapshot, and the walk still descends into the failing component’s children. "error" is reserved for that purpose, and local state keys must not collide with subcomponent names; a hook violating either is reported as that node’s error. With keys, returns a flat mapping with one entry per match. Each key is a /-separated path through the component tree: every segment names a subcomponent, and the final segment may instead name an entry in that component’s local state. Because structure is the nesting, a literal path is the same as plain indexing — getState(["left_arm/joint_positions"]) returns the value of getState()["left_arm"]["joint_positions"] — and a path ending on a subcomponent yields that component’s full nested node. Segments may use shell-style wildcards over subcomponent names — * matches within one chunk and ** matches any chain of chunks — so "*_arm/joint_positions" fans out to one entry per arm, keyed by the concrete matched path. Wildcards never match state entries; only a literal final segment does. A key that matches nothing raises, so a typo is loud rather than silently absent. A matched component whose state read failed yields &#123;"error": "..."&#125; at its path. Keyed reads are lazy: a hook runs only where a key lands — a literal path executes the final component’s hook alone (not the nodes traversed on the way), a glob executes only the matched nodes, and each component’s hook runs at most once per call however many keys reach it. Components with a selective-read hook (_local_state_entries — every Robot with registered state getters) go further and execute only the getters a key names, so a ** glob probes their registries without touching hardware. The caller pays only for the state actually requested; ** and the no-keys form visit the whole tree because that is the request. State is cheap by convention: local state carries kinematics, status, and health — never bulk sensor payloads (camera frames, point clouds, scans), which stay in their dedicated methods (getImage, getPointCloud, …). Callable on a stopped tree — reading state after a soft e-stop is when it matters most — and on a partially started one, where unstarted components report a per-node error instead of failing the call.
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State paths to read, or None for the full nested snapshot. A single string is shorthand for a one-element list.
Returns: The nested state snapshot when keys is None, otherwise a flat mapping of matched path to state value or nested node. Raises: TypeError: If keys is neither None, a string, nor a list/tuple of strings. ValueError: If a key is empty, has an empty path segment, or matches no subcomponent path or state entry.

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grasp()

Signature
Close the gripper to grasp an object. This method blocks until the gripper is fully closed or hits an obstacle. The gripper grasps with maximum force (80N) and maximum velocity (0.2 m/s).

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moveToDeltaPose()

Signature
Offset the robot end effector by the specified delta pose from its current pose (with respect to the base frame).
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required
Pose offset to compose with the current pose. The position is added to the current position and the orientation is composed with the current orientation.
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default:"True"
Wait for movement to complete. Defaults to True.

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moveToHome()

Signature
Move the arm to its predefined home pose. Equivalent to moveToNamedPose("home", blocking=blocking). The "home" entry is registered in named_poses from the abstract home_pose property during Arm.__init__, so every concrete arm has it. Subclasses may add hardware-specific tuning parameters as keyword-only arguments after blocking.
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default:"True"
Wait for movement to complete. Defaults to True.

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moveToNamedPose()

Signature
Move the robot to the joint angles of a named pose. Subclasses may add hardware-specific tuning parameters (timing, force thresholds, etc.) as keyword-only arguments after blocking.
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required
Name of the pose to move to (case-insensitive).
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default:"True"
Wait for movement to complete. Defaults to True.
Raises: ValueError: If pose_name is not found in the named poses dictionary.

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moveToPose()

Signature
Move the robot end-effector to a specified pose
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required
Target pose (position in meters, orientation as a unit quaternion) in the robot’s base frame.
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default:"True"
Wait for movement to complete. Defaults to True.
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default:"2.0"
seconds to complete the movement (unless you’re already there)
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default:"0.5"
seconds to spend accelerating in a trapezoidal motion profile
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default:"False"
If False, send discrete commands that are executed by the robot’s motion generator. Otherwise, continuously stream commands to be executed by the robot’s low-level joint position controller.
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default:"False"
Currently unused. Not implemented yet
Returns: True if the movement command ended without force or errors, False otherwise. Raises: ValueError: If moving_time or accel_time are not positive floats or ints. NotImplementedError: If high_frequency is True. Not implemented yet.

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release()

Signature
Open the gripper to release an object. This method blocks until the gripper is open to its max width or hits an obstacle. The gripper releases with maximum force (80N) and maximum velocity (0.2 m/s).

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removeNamedPose()

Signature
Remove a named pose from the dictionary of pose_name:joint_angles pairs.
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required
Name of the pose to remove (case-insensitive)
Returns: list: Joint angles (radians) of the named pose that was removed, or None if the named pose did not exist

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setJointAngles()

Signature
Set joint angles in radians. Commands the arm to move its joints to the specified angles. Can be blocking or non-blocking depending on the blocking parameter. If high_frequency is False: a trapezoidal motion profile is generated (ending with zero velocity) with the given moving_time and accel_time, and the robot’s internal motion generator will smoothen and execute the motion. If high_frequency is True: the joint angles are continuously streamed directly to the robot’s low-level joint position controller. It is assumed that this function is called in a high-frequency (~1-100 Hz) control loop. This is useful for running models that assume full control of the robot, like Vision-Language-Action models, but doesn’t behave well if there is a large delta in time or joint angles.
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required
List of target joint angles in radians, starting with the base joint.
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default:"True"
Wait for movement to complete (default True)
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default:"2.0"
seconds to complete the movement
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default:"0.5"
seconds to accelerate from zero to full velocity (another accel_time is needed to decelerate to zero)
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default:"False"
If False, send discrete commands that are executed by the robot’s motion generator. Otherwise, continuously stream commands to be executed by the robot’s low-level joint position controller.
Returns: True if the movement command was successful, False otherwise. Raises: ValueError: If angles list length does not match the number of joints. ValueError: If moving_time or accel_time are not positive floats or ints.

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startFreeDrive()

Signature
Enable free-drive (hand-guided) mode. The arm becomes compliant and can be moved by hand while supporting its own weight. Position-control commands such as moveToPose and setJointAngles are not active in this mode — call endFreeDrive to return to position control. All six Cartesian axes are unlocked, elbow motion is enabled, and damping is set to a moderate level on every axis.

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stop()

Signature
Halt all motion across this component’s tree (soft e-stop). Recursive walk owned by the base class: every subcomponent is stopped first (children before their parent, leaf-to-root; siblings in subcomponents insertion order), then this component’s own _stop_self hook runs. The walk is best-effort — a failing component never prevents the rest of the tree from being stopped; failures are collected and raised together after the walk completes. Components (and their subtrees) that have already been shut down are skipped. Safe to call repeatedly: stopping an already-stopped tree re-runs the hooks, which must tolerate that. Blocks until every hook has returned. Stops motion only; resources stay live and the component remains usable — telemetry and every other public method keep working on a stopped tree. Use shutdown to release resources. Stopping re-arms each visited component, so a later start re-runs the bring-up hooks — that is the stop-then-start restart path — but it does not revoke callability: only shutdown does that. Subclasses must not replace this method — per-component stop behavior belongs in _stop_self. An override may only extend the walk (adding a driver-specific mode, as UR5e does with its immediate escape hatch) and must delegate to super().stop() for the normal path; it must never re-implement the recursion. Raises: ComponentStopError: If one or more stop hooks raised. The walk still visited every component; the exception carries every (component_path, exception) pair.

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validateGrasp()

Signature
Check whether the end effector is currently holding an object. Thin wrapper that delegates to the configured end effector’s EndEffector.getGripDetected. Subclasses generally do not need to override this. Returns: True if the end effector reports an object in its grip, False otherwise. Raises: RuntimeError: If no end effector is configured on this arm. NotImplementedError: If the configured end effector does not support grip detection.

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Properties on the robot

Read as robot.<property>; each read runs the getter on the robot.
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list[float]
Joint angles (radians) with the arm over the workspace, joints at 90 degrees.
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Dict[str, List[float]]
Registered poses as &#123;name: joint angles in radians&#125; (a copy).Mutating the returned mapping does not change what the arm knows: register and remove entries with addNamedPose and removeNamedPose, or assign a whole mapping to replace them all.

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Configured children

  • robot.end_effector — the gripper, chosen in the robot’s configuration; when one is fitted, its methods are the EndEffector interface’s.

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Not implemented on this robot

Declared by the interface, raises NotImplementedError here: followJointTrajectory.

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Lifecycle and configuration

The driver’s own bring-up and configuration hooks. The edge runs them when the robot comes up; do not call them from a program. Note that robot.shutdown() on the proxy is not the method below — it is RemoteRobot.shutdown(), which closes your connection and leaves the robot as it was.
  • addSensor() — Add an external sensor to the robot.
  • addSubcomponent() — Attach a child component under a name.
  • builtin_subcomponents() — Declare the children this class always ships with (customization point).
  • configHash() — Hash this component’s serialized config subtree.
  • config_schema() — Config-args schema for this robot, derived from the constructor.
  • from_config() — Construct this component and its config-declared subtree.
  • getIdentity() — Get this component’s own hardware identity (serial, model, version, MAC).
  • getRobotId() — Stable, readable identifier for a robot or rig, for a database key.
  • serialize() — Serialize this component tree back to its config envelope.
  • setup_shutdown_handlers() — Register the process-wide atexit and signal handlers for safe teardown.
  • shutdown() — Shut down this component’s tree, halting motion and releasing resources.
  • start() — Bring this component’s tree online (connect, enable, arm).
The contract these methods implement is Robot interface; values returned are grid-types (camera reads return Image — call decode() for an ndarray). You reach the robot through connect.