Pinch grippers

Using a pinch gripper with Pally is possible, but it requires some adjustments. Here are some helpful tips and things to keep in mind when using

 

Common challenges overview

  • Only one side moves

  • Not leaving enough room for gripper

  • Vertical exit needed




Pinch grippers are configured like other custom grippers by adding the length, width, height and weight. It's keep in mind that the TCP is configured correctly. Sometimes, when only one side moves, it may be necessary to change the TCP from one product to another. This can be easily accomplished by using an If statement at the beginning of the program to check which pattern is being used.
Gripper and TCP check

 

Example picture of code:

 

Vertical exit is also needed when using a Pinch gripper.

Vertical exit is the default setting in Pally, and the total length of the vertical motion can be controlled by the parameter rf_foam_height (also works for pinch grippers).

Just add the following code in the initial MoveJ StartPosition (example):

rf_foam_height = 0.18

 

Vertical exit is active only if bit 2 is set in the rf_release_strategy variable. Read more about release strategy here - Release Strategy

Just add the following code in the initial MoveJ StartPosition (example):

rf_release_strategy = 6



Setting up the pattern


To create the pattern, it is suggested to use an inverted approach. (see picture below) This enables Pally to begin working from the side closest to the robot and move outwards, ensuring that the gripper always has enough space to open.

You can also use the “Customize box index” to arrange the boxes the way you want them, to ensure you always have free space to open the pich gripper. See picture below

 

To prevent collisions, it is suggested to lock the boxes. (see picture below) This will ensure it is always placed in the same positions. To make this easier to visualise, enable Lable orientation; this will show you how the boxes are facing.