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RobVision Picking

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Requires the RobVision add-on.

In order to use RobVision, you need to use two Nodes: a RobVision Trigger Node and a RobVision Picking Node. Together, the Nodes provide the RobVision functionality.

General workflow​

As the computation of the Pick Pose might take some time, the RobVision feature works asynchronously.
This way, the Robot can continue doing other things while the computation takes place in the background and standstill time is avoided.
To enable this, the feature is split into two Nodes:

  • The RobVision Trigger Node triggers a camera capture and the Pick Pose computation in the background, but continues right away.
  • The RobVision Picking Node waits for the computation to be finished and moves to the Pick Pose.

You can trigger multiple computations for different solutions at the same time. The Solution IDs are used to track different computations. With those IDs, the Picking Node knows which Trigger Node it refers to.

RobVision Picking Node​

Here you need to select the Solution and optionally define the Approach Trajectory for how the Pick Pose will be approached.
On execution, the Robot will move to the Approach Pose along the appraoch trajectory, from there to the Picking Pose and then back to the Approach Pose along the reverse approach trajectory.
If Batch Mode is enabled, this will repeat for all detected items. Otherwise, only the first one will be processed.

This Node has six outputs:

  • Before item approach: This will be executed before the approach trajectory of each item.
  • At item: This output will be triggered after the Robot has moved along the defined approach trajectory to the Pick Pose. You can use it e.g. to close the Gripper.
  • Process item: If an approach tracjectory is defined, this will be executed after the Robot moves to the approach pose along the trajectory. Here you can e.g. place the item somewhere else.
  • After Completion: After all the items have been processed, the Node itself is finished and continues the Flow here.
  • No Detections: If no Pick Pose could be determined, the Flow will continue on this output.
  • Error: If there was an error in the RobVision Server, the Flow will continue here. It can be useful e.g. to retry in case of a malfunction, or to inform the machine operator of a technical problem.

Picking Priority​

Here you can choose in which order the objects are going to be picked if more than one object gets detected.

  • Distance to Center prioritizes objects that are closer to the center of the image.
  • Confidence prioritizes objects with higher confidence values from the detection model.
  • Axis Priority is a powerful option in which objects are sorted by their position along selected axes, following a defined priority order. For each axis, the algorithm compares object positions (in the camera or Robot frame): if the difference is larger than the tolerance, sorting is determined by the chosen direction — Ascending (smaller coordinate values come first) or Descending (larger coordinate values come first). If the difference is within tolerance, the next axis in the priority list is used. If all axes are within tolerance, the objects are treated as equal.

picking-priority

In this example, sorting starts with the Z axis (first priority). All objects are at the same height, so the algorithm moves to the X axis. Objects 1, 2, and 3 have nearly the same X position — within the defined tolerance — so they're considered equal on that axis. The next priority axis is Y, where Object 1 has the lowest Y value, so it comes first. Small variations due to imperfect parts, size differences, or measurement noise are handled by the tolerance setting, which prevents insignificant deviations from affecting the sorting order.

Reverse Item Approach Trajectory​

This option will make the Robot execute the Item Approach Trajectory in reverse after each item. Note that the reversed Item Approach Trajectory will be executed after the At Item branch and before the Process Item branch.