Gazebo effort / position controllers

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Hi, Im working with panda model with arm and gripper in gazebo, when i set controllers for arm&gripper to

• position_controllers/JointTrajectoryController

model moves fine but he can't grab any object to gripper - object slides from gripper (it's not effort setting).

• effort_controllers/JointTrajectoryController

model moves ok (pid adjust), gripper can hold object and keep it, but there exist error GOAL_TOLERANCE_VIOLATED

When i set arm to

• position_controllers/JointTrajectoryController

and gripper to

• effort_controllers/JointTrajectoryController

my model behaviour is the same as in first case where model has position controller for all links - i can't grab anything with gipper.

How to set controllers to be able to grab objects and avoid setting pids for effort controllers. I don't want also use plugin for grasping.