PincOpen Driver

pinc_open_driver provides a ROS 2 hardware interface that allows users to switch between a mock interface and the actual hardware of Pollen Robotics' open-source PincOpen Gripper gripper. It includes a simplified URDF based on the PincOpen Gripper design which allows users to incorporate this gripper into their existing robot URDF. It also provides a YAML file that sets up two controllers: position_controllers and joint_trajectory_controller. The package enables development and testing with either simulated or physical hardware. It integrates with ros2_control and supports easy switching between modes.

Getting Started

Launch one (and only one) of these three launches

Display Launch

• The display launch loads the robot description and uses the joint_state_publisher_gui to send commands to the visualized model.

clear; ros2 launch pinc_open_driver display_gripper.launch.py

Note: The URDF includes a simplified link model and does not model the exact kinematic 4-bar linkage.

Mock Launch

• The mock launch activates the controllers and simulates the hardware. The default controller activates is the joint_trajectory_controller commands can be sent via command line, using joint_trajectory_controller_gui via rqt, or our simple gui described below.

clear; ros2 launch pinc_open_driver mock.launch.py

This activates the "mock" loop back interface with a RViz viewer.

Hardware Launch

To use the hardware gripper, first set up the serial communications:

Serial Setup

On initial set up on a specific computer, navigate to the pinc_open_driver directory, Then, copy the provided udev rules below to enable serial communication:

sudo cp 99-pinc-gripper.rules /etc/udev/rules.d
sudo udevadm control --reload-rules
sudo udevadm trigger

Hardware Launch

clear; ros2 launch pinc_open_driver hardware.launch.py

This activates the hardware driver and a RViz viewer.

ros2_control Parameters

The following parameters configure the gripper hardware, communication settings, and visualization defaults. All parameters may be overridden via the launch file. See launch/hardware.launch.py for usage example.

Parameter	Default	Description
use_mock_hardware	false	If true, uses a mock hardware interface instead of communicating with the physical gripper. Useful for simulation and testing.
prefix	pinc_open_	Prefix applied to joint and link names. Allows multiple instances of the gripper to be spawned without name collisions.
default_color_rgba	0.0 0.0 1.0 1.0	Default RGBA color applied to gripper visual links. Values are in the range [0.0, 1.0].
default_linkage_color_rgba	0 0.5 1.0 1.0	RGBA color applied to linkage components of the gripper model.
default_tip_color_rgba	0.0 0.0 0.7 1.0	RGBA color applied to the gripper tip components.
baud_rate	1000000	Serial communication baud rate used to communicate with the gripper servo. Must match the servo configuration.
comm_config_delay_ms	100	Sleep delay (in milliseconds) applied during serial port configuration. This value is used in seven sleep calls during on_configure. Raw USB seems to work fine with lower values, but UR socat interface seems to require higher values (~300ms) to allow the system to connect reliably.
serial_port	/dev/pinc-gripper	Serial device used to communicate with the gripper hardware.
serial_timeout	20	Serial communication timeout in milliseconds before reporting a communication error.
servo_id	6	Servo ID of the gripper actuator on the serial bus. Must match the configured servo ID.

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ROS 2 controllers available for use

The provided demo includes set ups for both

• JointTrajectoryController(pinc_open_driver_trajectory_controller) default
• JointGroupPositionController (pinc_open_driver_position_controller)

• User can switch between controller using the controller manager plugin in rqt.

By default, the Hardware and Mock launches activates thepinc_open_driver_trajectory_controller JointTrajectoryController interface. Commands can be sent via command line, standard action interfaces, and rqt gui or our pinc_open_driver_control_gui.

The demonstration controllers are named based on the gripper prefix defined in the launch files. These can be modified for other prefixes (e.g. 'left_' and 'right_').

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Helper Scripts

A few simplified logging and plotting scripts are available for use during testing.

• ros2 run pinc_open_driver pinc_open_driver_control_gui

  Use sliders and buttons to set goal joint positions and then "send a trajectory". Note, this basic spline trajectory command works with the JointTrajectoryController, but does not perform collision checking.

• ros2 run pinc_open_driver pinc_open_driver_monitor

  This echos joint and controller statuses to terminal while also logging data to the $WORKSPACE_ROOT/log/pinc_logs folder.

  Use Ctrl-c to terminate and close the log file.

• ros2 run pinc_open_driver plot_pinc_open_driver_log

By default, this command plots the last file saved by pinc_open_driver_monitor in the $WORKSPACE_ROOT/log/pinc_logs folder. Optionally the user can specify the full path to a specific log file name to retrieve a log from an earlier time.

• ros2 run pinc_open_driver read_servo

  Prints data from all accessible servo addresses with a description of each address including its data length, and whether it is read-only or read/write, and its current value.

Note: These basic helper scripts currently have hard coded topic names, and may need to be modified for your use case.

Publications

Please use the following publications for reference when using PincOpen Driver:

• D. K. Logan, I. G. Conner, and D. C. Conner, "ROS 2 Hardware Interface for the PincOpen Gripper", IEEE SoutheastCon 2026, Huntsville, AL, USA, 2026, to appear.