Okura Yusoki A Series Manual page 110

For vacuum hand (end effector) the frame depth is used in calculations to account
for the collapse of vacuum cups. The frame depth is the distance from the hand (end
effector) mounting flange surface to the bottom of vacuum cups when the hand (end
effector) is under vacuum holding onto product.
If you are using a carton box type hand (end effector) with paddle and height of the
paddle is relatively short, you may have to adjust the pick-up position height
because of the tolerances that are build into the OXPA-QmII calculation (depending
on the height of the handle article).
The distance required to avoid interference between the hand (end effector) and the
product during pick up is automatically added to the pick-up height at the station.
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