Question, not issue: about gripper control in simulation about cob_robots HOT 2 CLOSED

I assume you're refering to the Care-O-bot 3 gripper which is a Schunk SDH. For gazebo we modeled each joint as a revolute joint and added a joint trajectory controller to control all 7 joints in one action.
see
URDF: https://github.com/ipa320/schunk_modular_robotics/tree/indigo_dev/schunk_description/urdf/sdh
controller: https://github.com/ipa320/cob_robots/blob/indigo_dev/cob_controller_configuration_gazebo/controller/gripper/gripper_controller_sdh.yaml
launch file:

    <!-- Gripper -->
    <include file="$(find cob_controller_configuration_gazebo)/launch/components/generic_controller.launch">
        <arg name="component_name" value="gripper"/>
        <arg name="version" value="sdh"/>
    </include>

from cob_robots.

There are definitely better forums for such kind of questions, e.g. answers.gazebo, answers.ros or the ros_control SIG

Just one more hint:
Why do you want to use effort controllers? Is the actual hardware controlled by sending efforts, too?
If you want to just control the joint positions of the gripper joints, try using a JointPositionHardwareInterface and the JointTrajectoryController in gazebo. By doing this, you don't need to find PID values as you would be using a forward command controller.

Could you please close this issue and ask further questions on the forums mentioned above?

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