Delayed response in over communication on EthernetKRL

  • Hi,

    I am looking for a solution to solve delayed response by the KUKA robot over real time data transfer ethernetKRL.

    We have a setup in which we are sending data from the force torque sensor to produce the movement of the robot in the direction of the force. The data transfer is working at 16ms approx, which is same as the data refresh rate of the sensor.

    I am using LIN_VEL function to do this task.

    As I mentioned above the problem lies in the delayed response of the robot. I suppose this delay is because of the robot takes time to take command for new position, only when the previous position is attained (within C_DIS) the new position would be triggered.

    I believe there is a better way to do this task, Please share your ideas on this.

    Other details - Kuka KRC4 compact, EthernetKRL 2.2

  • AD
  • Are you attempting to perform realtime control with EKI? EKI is explicitly not designed for this. This is what RSI is for. EKI is not realtime -- it is intended for non-realtime, non-time-critical communications. With EKI, the robot cannot respond to a new force until after the current active motion is complete. As such, any "realtime" attempt using EKI is going to be very "chunky" in dV/dT, at best.

  • Thanks Skyfire for the reply.

    Yes, you are right I am trying to achieve real time motion over EthernetKRL. I believe the problem of delay lies in motion function I am using. I just tried with PTP _ REL instead LIN_REL and the response of the kuka is quite better with faster data exchange (4ms). Thanks for the tip about the blcoking behaviour of motion in EthernetKRL.

    P.S. - Here, we worked with RSI, but the drawback is that RSI only provide XML format data, which is heavy to treat every 4ms/12ms and on the same time EtherNetKRL supports the binary type format.

    I believe if the delay is well below threshold we can work with ethernetKRL otherwise we will have to move to RSI.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account
Sign up for a new account in our community. It's easy!
Register a new account
Sign in
Already have an account? Sign in here.
Sign in Now