New 50366 Reference Error - System Limits [PickMaster 3]

PickMaster
1

I have a multi-move system, 2 robots / 1 IRC5, where each robot performs a double-pick process. I originally had a problem when trying to run the robots faster than 1200 mm/s but this was corrected by increasing the adjustment_speed parameter to 2500.

The error returned today as well as the axis 4 motion supervision error. I am wondering if I have reached the limit of my system or if I need to re-define the tcp data.

I have been running the robots at 2000 mm/s, conveyor at 400 mm/s (product spaced at 8 inch intervals). We decided to increase the robot speed to 3000 mm/s and maintain the existing conveyor speed but reduce the product spacing to 3 inches. As we did so, I got an axis 4 motion supervision error as well as the internal reference error -302.

My tool weighs 2.139 kg’s without product. The product weighs 0.127 kg and with the double pick, the total weight equals roughly 2.4 kg’s. The center of gravity of the tool is well within the payload curves. I have the ItemLoad set to 0.127 kg for the 1st pick and then I have the ItemLoad set to 0.254 kg for the 2nd pick. My Tool TCP’s are as follows:

TASK PERS tooldata tRob2GripPickLeft:=[TRUE,[[60.325,0,97.0534],[0,0,0,-1]],[2.139,[0,0,41],[0,0,0,-1],0.013,0.0151,0.00739]];
TASK PERS tooldata tRob2GripPickRight:=[TRUE,[[-60.325,0,97.0534],[0,0,0,-1]],[2.139,[0,0,41],[0,0,0,-1],0.013,0.0151,0.00739]];
TASK PERS tooldata Gripper:=[TRUE,[[0,0,97.0534],[0,0,0,-1]],[2.139,[0,0,41],[0,0,0,-1],0.013,0.0151,0.00739]];

I have 2 pick routines, 1 for the left and 1 for the right.

Have I reached the limit of the system given the large tool payload?

What do you think about my problem?

Thanks,

Dino

2

I believe that I have figured it out my issue.

I did the following today:

  • Increased tool weight as well as gripper payload data
  • Increased start up ramp system parameter (under proc)
  • Increased z pick position so that I did not dig into the product too much. Was able to run the robot at 4500 mm/s with no issues.

I am still open to hear if anyone has any other ideas or if anyone has encountered a similar issue.

Dino

3

We have found that pick elevation plays a roll in pickmaster motions. We have tuned the accel / start ramp parameters with success, but sometimes it still picks very inaccurately. We will then increase the pick elevation and it seems like the additional motion/time allows the motion planner to do a better job.

4

I agree. What I find so weird is that the motion is extremely fluid when I pick upstream and then downstream. The moment, I reverse the order, the motion is jerky and it seems like the robot has issues trying to coordinate the tracking / picking.