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Dimitris_MINESDimitris_MINES Posts: 4 Apprentice
Hi All,

I am working on the Universal robot UR3 with 2F gripper(2F-140) & FT300 with the latest ROS driver(Universal_Robots_ROS_Driver). Not the old ur_modern_driver.
With Ubuntu 18.04 and ROS Melodic version. The robot is controlled with Moveit! package and I am able to control the robot's position and perform path planning.
I need to control the gripper(activation, open, close, reset) and use the Force/Torque sensor data through ROS from the robot. I found that it can be done when the gripper & the FT sensor are directly hooked into a computer. But I need it to be done when the two parts are connected directly to the robot. Is there a way or if anyone can direct me how to proceed with, that would be helpful.
I looked at this tool communication but does it works also for UR robots?

Thank you in advance,


  • bcastetsbcastets Vacuum Beta tester Posts: 642 Expert
    I would recommend to have a look to this post:

    There are several option to control a gripper or ft300 connected to the robot.
    1-via sending urscript using UR client interface
    2-via rs485 urcap provided by UR
    3-via sending commands to robotiq urcap server.

    Whatever the solution you go for there is the work on the way to make things works.

    The easiest solution is to have everything directly correct on the PC.

  • Dimitris_MINESDimitris_MINES Posts: 4 Apprentice

    First of all thank you for the quick answer to my question.
    Firstly, for the urscript I have the same problem . Even I can popup messages to the robot, Gripper doesn't
    response to rq_reset() / rq_activate() ... etc.
    I am using port 50002 in order to exchange messages.
    Furthermore, my real issue is that I have the same usb cable for the wrist camera & gripper. When I connect them
    directly to my computer I cannot work with both of them at the same time. I can use the wrist camera or the gripper
    but not both of them at the same time. This is the reason that I want to have everything connected to the robot
    control hub. Because it seems that then I can work with the wrist camera and the gripper simultaneously.

    Thank you in advance,

  • bcastetsbcastets Vacuum Beta tester Posts: 642 Expert
    It should be possible to have a gripper, a ft300 and a wrist camera connected on a pc have them working simultaneously.

    The wrist camera act like a webcam when connected on a pc.
  • Dimitris_MINESDimitris_MINES Posts: 4 Apprentice
    Yes, it acts like a webcam but when I am trying to use it, the connection with the grippers stops. And
    when I use only the camera and then I am trying to connect with the gripper the picture freezes. You
    think is it possible to use the same USB cable in order to manipulate wrist camera & gripper at the same
  • bcastetsbcastets Vacuum Beta tester Posts: 642 Expert
    In any case you need have a USB port for each devise. If you use 1 USB port of the PC then you will need a USB HUB.
    I think it should work.
  • Dimitris_MINESDimitris_MINES Posts: 4 Apprentice
    As you can see at the manual of Robotq Wrist Camera the configuration with the gripper
    (3.4.1 Combo of 2-finger Adaptive Gripper and Wrist Camera for UR) implies that we use
    the same cable for the camera and the gripper. Should I change configuration in order
    to use different USB cables for every device?

  • bcastetsbcastets Vacuum Beta tester Posts: 642 Expert
    Indeed when you mount the gripper on the camera all the communication is handled with a single cable.
    It is still possible to mount the gripper and the camera with separate cables. The camera is delivered with a mounting plate. You can mount on this plate a gripper coupling and wire the gripper directly to the PC.
    I am not familiar with the communication process when camera and gripper are on the same cable but it should be possible to make both working at the same time from your PC.
    I create a support ticket to try to give you more information on this.
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