Warning

You are reading the documentation for an older Pickit release (2.3). Documentation for the latest release (3.3) can be found here.

Picking

Pickit is not only about detecting objects, but also about being able to pick them. While the Detection page is concerned with what to detect, the Picking page is concerned with everything that revolves around how to pick a detected object: From which points can it be picked? With which tool? Is the pick collision-free?

Tip

You can learn about the main ideas behind how to pick by watching this video tutorial.

Robot tool model

Pickit allows to model the robot tool that is used for picking. The tool model is useful for visually confirming the correct location of a pick point, and can also be used to prevent collisions between the tool and a bin or other objects.

Pick points

A pick point represents where an object can be picked by the robot. It is specified as a position and orientation relative to the object, where the robot Tool Center Point (TCP) should move to perform a pick. What constitutes a good pick point depends on both the gripping device and the object to be picked. The following articles detail how pick points are managed by the different detection engines:

Pick strategy

Once pick points are specified, there are a number of options that influence how objects are picked.

  • Object ordering: When multiple objects are detected, object ordering determines the order in which they should be picked (more).

  • Preferred pick point orientation: Pick points can have flexibility in how they are oriented. This flexibility can be used to favor pick orientations that are easier and faster to reach by the robot (e.g. less wrist motion):

  • Maximum tilt from reference frame Z-axis: When a pick point is too tilted, it is more likely that picking it will result in unreachable robot motions. This option allows to label objects that are too tilted as unpickable (more).

  • Enforce pick point alignment This applies only to the Flex and Pattern detection engines, and is explained in detail in this article. If using Pickit Teach, refer to the more powerful flexible pick orientation feature.

Collision prevention

In constrained picking scenarios like bin picking, it is important to prevent the robot tool from colliding with the bin or other objects. Pickit allows to model the robot tool and to perform collision checks with the bin and other objects.