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Which method can be trusted to determine the cycle time

#1
Hello everyone!

I have some problems with the approximation of the cycle time.

Method 1:
When I run the simulation, I get a cycle time of 3min 35s at the end of the simulation (according to https://www.youtube.com/watch?app=deskto...remyRoboDK).

Method 2:
If I run the simulation in real time speed ("Tools"->"Options"->"Motion"->”Simulation time ratio” = 1) and stop the time with a stopwatch, I get a cycle time of about 5min 12s.

Method 3:
If I run the "CycleTimeDisplayAll" script with all my different speeds and add up the correct subroutine times at the correct speeds, I get an estimated cycle time of 4min 55s. (according to https://robodk.com/forum/Thread-estimate...cycle+time)
 
What I do in the program:
1. set the rounding factor to 20mm in the main function.
2. set the speed limit to 300mm/s and 15°/s (this gives me approximately the same speed for joint movements as for linear movements)
3. run two subroutines
4. change the speed limit to 600mm/s and 28°/s
5. run more subroutines
6. move the robot on a linear axis
7. run more subroutines
8. move the robot back on a linear axis
9. program finished.
 
I have read about the settings "Extras"->"Options"->"Movement"->"Strictest restrictions" (according to https://robodk.com/forum/Thread-Cycle-time-differences and https://robodk.com/doc/en/General.html#CycleTime), which always limit the robot speed to the lowest speed limit, if I understand this correctly. I don't want that, because high joint speeds can occur in my program with linear movements. So I want the cycle time to be estimated for linear and joint movements. Method 4: However, if I use this setting, I can change the first speed limit, but the cycle time remains at 5 minutes and 12 seconds after the simulation has run through.

If I take a look at the "Robot parameters" window during the simulation, the change of the maximum velocities works fine, which can also be seen visually during the simulation.
 
Main question: Which method can I trust the most to estimate an approximate cycle time?
(Program is attached)

Kind regards,
Alexander


Attached Files
.rdk   Cycle_time_issue.rdk (Size: 3.14 MB / Downloads: 28)
#2
When you run a program (double click on it), RoboDK will calculate the cycle time it takes assuming the robot can fulfill the programmed speed and acceleration (method 1).

If you time it with a clock at a simulation speed ratio of 1, you may get longer cycle time because there are additional events happening in RoboDK that are not accounted for (render events, calculations, etc).

RoboDK cycle time calculation is an estimate, the real timings will be provided by the corresponding RRS library (not all controllers provide it).

You can find more information about cycle time estimate and related settings:
https://robodk.com/doc/en/General.html#CycleTime
  




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