External Axis (on Rotary Table) - Rotation Speed Control

  • Hello!

    My Robotic system consist of a KR60-3 Robot with an external axis (MG_480_180_30 Motor). External Axis is mounted on a Rotary Table and therefore it is set to form asynchronous, uncoordinated movement of the table with desired speed.


    I wish to design a program that reaches the desired RPM of axis E1 as a function of time (i.e. the rotational speed should ramp up or ramp down wrt to time defined by user)


    I have set E1 as asynchronous.

    I use $VEL_EXTAX[1]=<value>

    ASY_PTP(<Value>)


    by changing the $VEL_EXTAX[1] between the program i get a message "Value is inadmissible"


    Kindly help me with the right set of codes.


    Thanks.

  • Place your Ad here!
  • I am passing an integer value.


    Also, by passing an integer value how do i get precise RPM value??


    Also, how to do i get a very smooth RPM increment. As of now i get an jurking motion as i cannot finely increment motion ...

  • Also, by passing an integer value how do i get precise RPM value??


    Also, how to do i get a very smooth RPM increment. As of now i get an jurking motion as i cannot finely increment motion ...

    programmed speed is not a precise RPM value. it is a desired value or upper limit. this is a step function meaning that programmed value can (and it does) experience sudden changes. for example from 100% to 30% and then to 100% again.


    actual value is result of computation by motion planner, filtering and then smoothed by PI controllers (speed and position) which is how you get gradual and smooth transitions. there is simply very long path between setpoint (programmed value) and actual RPM of the motor.


    robot may not be able to even reach programmed velocity, specially if move is short and acceleration is low.


    so programmed value can be an integer 0-100%


    but commissioning is needed to ensure that that scaling is correct (number of poles, gear ratio etc.) the 100% does not exceed any of the limits (motor, gearbox, whatever)

    1) read pinned topic: READ FIRST...

    2) if you have an issue with robot, post question in the correct forum section... do NOT contact me directly

    3) read 1 and 2

  • after command run of ASYNC_PTP ; can you not change value of VEL_EXTAX[1] ?? is it true??


    After reaching a RPM; i am unable to change the RPM. By changing the value of VEL_EXTAX[] i get a prompt "Value is inadmissible"

  • Sure you can change it. Probably you just do it wrong. What your mistake is we can not know because we do not know nor have seen your program. So post it and please not some explanations what you are trying to do but exactly the program you run on the controller. Otherwise we stick to madly imprecise guessing as before and probably get bored answering your questions soon.

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

Advertising from our partners