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Adding shim paper in the Pallet Builder

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See video on how to add shim paper in the Pallet Builder

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Click the shim paper button as many times as there should be shim paper in the project. Drag the shim paper layer to the correct position on the pallet.

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Adding a shim paper routine on the robot

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• calculate the shim paper position on the pallet by using the global Pally variables "WorldPosition" (lifting column only), "PalletCenter", and "LayerAlt"

If you move the lifting column in the shim paper callback, don’t forget to move it back to the position where it was before picking the shim paper:

OnSheet callback:

my_last_pos = get_liftkit_position()

[…] do shim paper pick and place

move_liftkit(my_last_pos)

(This works with Ewellix LiftKit. For other lifting column types, please refer to the lifting column user manual)

If shim paper is picked in the center

sheet_point = pose_trans(WorldPos, pose_trans(PalletCenter, p[0,0,LayerAlt, 3.1415, 0, 0]))

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• sheet_point = pose_trans(WorldPos, pose_trans(PalletCenter, p[X, Y, LayerAlt, 3.1415, 0, 0]))

• where X and Y (The unit is meter) are the corresponding distances of the TCP from the center point of the shim paper (in the Cartesian coordinate system of the current TCP). Otherwise use 0, 0 so the paper center will exactly match the pallet center.
  

Explaining pose_trans()

When using the URScript function pose_trans() keep the following best practices in mind:

“The first argument, p_from, is used to transform the second argument, p_from_to, and the result is then returned. This means that the result is the resulting pose, when starting at the coordinate system of p_from, and then in that coordinate system moving p_from_to.” (URScript Manual)

Practical examples:

1. move the gripper in the gripper coordinate system:

pose_trans( get_actual_tcp_pose(), p[0, 0, 0.1, 0, 0, 0] )

2. move the gripper in the base coordinate system

pose_trans( p[0, 0, 0.1, 0, 0, 0], get_actual_tcp_pose() )

3. move the gripper in the coordinate system defined by the pallet calibration (with floor correction)

pose_trans( p[0, 0, 0.1, 0, 0, 0], pose_trans(pose_inv(PalletCenter), get_actual_tcp_pose())

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