Post Processors
This section will show you how you can modify an existing post processor to force an axial movement using joint values instead of Cartesian values.
In this example we’ll apply this change to an ABB IRC5 robot controller.
1.Find the programming manual of your robot controller. In this example we use the ABB IRC5 RAPID programming manual.
2.Look for the joint movement instructions. In this case, ABB’s absolute joint movement command is called MoveAbsJ. This command requires a jointtarget variable that defines the joint axes.
3.Select Program➔Add/Edit Post Processor and select the post processor you are currently using to modify it. If you are currently using a customizable post processor it will be selected by default.
4.You should look for the MoveJ function inside the post processor. This function defines the way post processors generate the joint motion commands. Alternatively, RoboDK uses MoveL for linear movements. Using Python programming language, modify the line that is added to the program file to provide joint angle information, as shown in the following image.
5.Finally, you may need to modify the way the post processor converts the joint angles or the pose to a string. The functions angles_2_str and pose_2_str define how the joint angles and a pose, respectively, is converted to text.
Most RoboDK post processors use joint data for joint movements and Cartesian coordinates for linear movements. It is recommended to always start the first point in a sequence of linear movements as a joint movement, specifying joint coordinates. This avoids starting a program with the wrong robot configuration and reaching a singularity or axis limits.