Real UR5 robot does not stop immediately upon receiving moveit stop command

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Setup:

• ROS Melodic
• Ubuntu 18.04
• UR5 robot
• UR software v3.8
• URcaps version 1.0.2
• Universal_Robots_ROS_Driver version used: branch master/commit

Issue

With planning cartesian trajectory with moveit as explained here, the robot does not stop immediately upon sending the stop() command but stops after 1 second approximately. On the controller side, the output shows path trajectory planning preempted, so it works as expected. We require the stop to happen almost instantaneously in order not to topple or destroy our manipulated object. We have tried also to set the speed scaling slider on the teach pendant to various values between 0-100%, but no effect. We have also tried changing the joint velicity limits in the joint_limit.yaml file in the respective moveit_config package.