grippers¶

Submodules¶

Classes¶

class brom_drake.control.grippers.gripper_controller.GripperController(gripper_type: GripperType, Kp: ndarray = None, Kd: ndarray = None)[source]¶

Description

A simple gripper controller with two modes: position and velocity. Both modes are essentially simple PD controllers.

Diagram

The GripperController LeafSystem can be represented with the following block diagram.

                        -------------------------
                        |                       |
                        |                       |
gripper_target -------> |   GripperController   | ---> applied_gripper_torques
gripper_target_type --> |                       |
                        |                       | ---> measured_gripper_position
                        |                       | ---> measured_gripper_velocity
gripper_state --------> |                       |
                        |                       |
                        |                       |
                        -------------------------

Parameters

gripper_type: GripperType: The type of gripper being controlled.
Kp: np.ndarray, optional: The proportional gain matrix for the PD controller. By default, this is set based on the gripper type.
Kd: np.ndarray, optional: The derivative gain matrix for the PD controller. By default, this is set based on the gripper type.

CalcGripperPosition(context: Context, output: BasicVector)[source]¶

Description

Callback function for the measured_gripper_position output port. This method computes the gripper position based on the current state input.

Parameters

context: pydrake.systems.framework.Context: The current context of the system.
output: pydrake.systems.framework.BasicVector: The output vector to store the gripper position.

ComputePosition(state: ndarray) → ndarray[source]¶

Description

Compute the gripper position from state data. This is especially useful for the 2F-85 gripper, since the state does not map neatly to the finger positions.

Parameters

state: np.ndarray: The state vector of the gripper.

Returns

finger_position: np.ndarray of shape (2,): The positions of the gripper fingers.

ComputeVelocity(state: ndarray) → ndarray[source]¶

Description

Compute the gripper velocity from state data. This is especially useful for the 2F-85 gripper, since the state does not map neatly to the finger positions.

Parameters

state: np.ndarray: The state vector of the gripper.

Returns

finger_velocity: np.ndarray of shape (2,): The velocities of the gripper fingers.

property gripper_width: float¶

Description

Return the gripper width.

Returns

width: float: The width of the gripper.

initialize_gains(Kp: ndarray, Kd: ndarray)[source]¶

Description

Initialize the gains for the gripper controller.

Parameters

Kp: np.ndarray: The proportional gain
Kd: np.ndarray: The derivative gain

class brom_drake.control.grippers.gripper_target.GripperTarget(*values)[source]¶

Functions¶

(None found)

Variables¶

brom_drake.control.grippers.gripper_controller.package_dir = '/home/runner/work/brom_drake-py/brom_drake-py/src/brom_drake/control/grippers'¶

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