my_baxter_hand.ros2_control.xacro

<?xml version="1.0"?>
<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
    <xacro:macro name="baxter_hand_ros2_control" params="side">
        <ros2_control name="${side}_baxter_hand" type="system">
            <hardware>
                <xacro:if value="${gazebo}">
                    <plugin>ign_ros2_control/IgnitionSystem</plugin>
                </xacro:if>
                <xacro:unless value="${gazebo}">
                    <plugin>mock_components/GenericSystem</plugin>
                </xacro:unless>
            </hardware>
            <!-- <joint name="${side}_gripper_base"> -->
            <joint name="${side}_gripper_base_jnt">
                <command_interface name="position" />
                <state_interface name="position">
                    <param name="initial_value">0.0</param>
                </state_interface>
                <state_interface name="velocity">
                    <param name="initial_value">0.0</param>
                </state_interface>
            </joint>
            <joint name="${side}_endpoint">
                <command_interface name="position" />
                <state_interface name="position">
                    <param name="initial_value">0.0</param>
                </state_interface>
                <state_interface name="velocity">
                    <param name="initial_value">0.0</param>
                </state_interface>
            </joint>
            <joint name="${side[0]}_gripper_l_finger_joint">
                <command_interface name="position" />
                <state_interface name="position">
                    <param name="initial_value">0.0</param>
                </state_interface>
                <state_interface name="velocity">
                    <param name="initial_value">0.0</param>
                </state_interface>
            </joint>
            <joint name="${side[0]}_gripper_r_finger_joint">
                <param name="mimic">${side[0]}_gripper_l_finger_joint</param>
                <param name="multiplier">-1</param>
                <command_interface name="position" />
                <state_interface name="position">
                    <param name="initial_value">0.0</param>
                </state_interface>
                <state_interface name="velocity">
                    <param name="initial_value">0.0</param>
                </state_interface>
            </joint>
        </ros2_control>
    </xacro:macro>
</robot>