Just when I thought I was getting the hang of PickTool....
This is what I have happening: I've set up my TrakFrame and Vision such that the robot picks the part without any issue when it's in a rotation similar to the Reference Position. The robot tracks the part on the moving conveyor belt very well.
However... this part comes down the line rotated around Z, either between -20 and +20, or between +160 and +200 (or, I suppose, between +160 and -160 the way irVision measures rotation). And if the part comes down the line "backwards", the UTool rotates to what looks like the correct orientation (relative to the part), but it's well off location along the X axis of the TrakFrame. The actual "tracking" motion is still correct however, following the motion of the conveyor.
Looking at the values in VR, when the part is pointing "forwards" (that is, the -20 to +20 of the Ref Pos), I'm getting X values in the range of -50. But when the part is "backwards" (between +160 and +200), the X value jumps up to the -300 range. I think this must be the root of the problem, but I've got no idea what's causing it. The R and Y values in VR look to be pretty reasonable, relative to the actual part position.
I've checked my UTool, and it's correct. And it's not a matter of the robot selecting the wrong UTool -- My Gripper has a large Y+ offset, but all my other UTools are 0'd, and the robot reaches far past where it should if one of the 0-Tools was active.
The irVision reference frame and the conveyor TrakFrame are aligned with each other to within 1deg, so I don't think that can be the issue.
My Pick Offset has only a Z value, everything else is 0, and the Approach/Retreat motions are correct relative to the Pick position. I'm not seeing any signs that any of the Frames are being flipped or inverted -- even when the robot goes much too far in X, its motions in Y, Z, and R appear correct.
My "Origin" in the irVision GPM tool is on the center of the part, so that should not throw the Pick position off in X the way I'm seeing.
So far, I've tried re-creating the entire PickTool recipe and irVision task completely from scratch 3 times, and I keep ending up with this same issue. I'm obviously missing something small but critical, but I cannot figure out what.