Adjusting tcp, robot drifts

Robot Controller
1

Hello all, i hope someone can help me with this problem as i’ve been puzzeling over it a few days now. i’m working on a material handeling application, i’ve got varying sized sheets coming down a conveyor we are measureing and squaring them up, then the robot (irb7600) must pick thim up and run the edge of the sheet along a glue dispenser. there is an infinate possibility for sizes of sheets so i was trying to write one program to handle all the sizes by adjusting the tcp.trans.y value, and from my experience with other robots this should work. but say i add 100mm to trans.y and move to a previously taught robtarget the robot move 95mm away in y and 10mm away in x. and if i add 300mm the robot moves 285mm and 30mm.

the tcp orients and jogs nicely (aligned) in all directions.

i tried to do a stationary tool and hold workobject but with the same results.

the only thing i can think of is that my tool has a 14.9deg rotation because the bolt holes did not align with the robot flange.

Any help would be much appreciated.

Russ

2

It seems that you define your tool only by adding data value.

Why not teach it by 6-point method?

3

Hello,

have you tried defining a work object at the glue dispenser? you should define the y axis of the work object u-frame along the direction of the size change. Then adjust the workobject o-frame to acommedate the different sheet sizes. wobj.oframe.trans.y.

You may also be able use the offset function on your Move instructions instead . MoveL Offs(p2, 0, nSizeOffs, 0), v1000, z1, tool1;

BR

Jim