Manual rotating around one Axis results in changes in all Axes?!

    I have an issue where I want to be able to offset a point, but mainly the rotations around XYZ, so WPR.

    L P[1] 500mm/sec FINE ACC30 Offset, PR[1]

    P[1] coordinates are:

    X: 796.821

    Y: -2281.020

    Z: 404.333

    W: -175.031

    P: 58.643

    R: 94.256

    This the point in question, the PR[1] offset, I am just changing the P component on it, so PR[1]:

    X: 0

    Y: 0

    Z: 0

    W: 0

    P: 15

    R: 0

    However, when that is applied the robot actually turns 15 degrees around the TOOL X axis, and not around the WORLD Y axis.

    XYZ changes work just fine and they are being applied according to the world frame.

    I have attached a short video to show my issue.

    I guess my question boils down to, how do I tell the robot "hey, take this point (P[1]) and apply P(Pitch) offset calculated around the WORLD frame"?

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    You need to set the frame in the program using a program instruction. Pressing shift-coord to change it only affects jogging, not program execution.

    That being said, rotational offsets should be done using a tool offset, not a frame offset. Rotational frame offsets are subject to gimbal lock in certain orientations.

    Quote from Sergei Troizky

    World is typically NUT and specified as User Frame 0.

    I wonder why your "World" is NDB? If such configuration of User Frame 1 is decided on purpose, do not call it "World", to avoid confusions.

    The configuration does not matter for frames. I really wish Fanuc wouldn't display it on the Frame setup screen.

    All uninitialized frames start off as 0,0,0,0,0,0 N D B, 0, 0, 0

    It is a common misconception that w, p, and r are axis rotations around x,y, and, z like experienced when jogging. They are in fact not. They are Euler angles and don't always play nicely with rotational frame offsets.

    Tool offsets are a much better solution for rotational offsets.

    Quote from HawkME

    It is a common misconception that w, p, and r are axis rotations around x,y, and, z like experienced when jogging. They are in fact not. They are Euler angles and don't always play nicely with rotational frame offsets.

    Tool offsets are a much better solution for rotational offsets.

    I tried with Tool_Offset and it is behaving the exact same way. Plus, since my tool frame is already rotated, I dont have an axis around which to rotate it in the vertical (XZ) plane. Both Tool_Offset and Frame Offset when changing P are rotating around the Tool Y axis and not around the world(or current frame) Y axis.

    As far as setting the frame and the shift+coord thing from your previous post, yes that is exactly what I am doing, I have an instruction that is setting the frame at the top of my program, I just screenshoted that to show my current frames.

    I still cant figure out how to rotate around the world Y axis (as it behaves when jogging) by setting a single offset.

    Edited once, last by Darkbound (August 9, 2021 at 3:21 PM).

    There are a few ways to achieve what you want.

    1. Don't use offsets, just teach points for each motion you need.

    2. Create a new tool frame that is rotated they way you need it to be in order to give you a tool axis to rotate around

    3. Use matrix multiplication to calculate a new frame or position.

    Quote from HawkME

    There are a few ways to achieve what you want.

    1. Don't use offsets, just teach points for each motion you need.

    2. Create a new tool frame that is rotated they way you need it to be in order to give you a tool axis to rotate around

    3. Use matrix multiplication to calculate a new frame or position.

    From the three options that you stated I think that the only option that will work is the third option, the rest will not work because I want use that offset as way for operators to do minor adjustments, because the parts that are being loaded into the machine are irregular so sometimes tiny modifications are needed , so I guess thats why creating a new frame will not work nor teaching points for each motion, because its just like fine-tuning of a point so my question here is:

    Is there a way to do matrix multiplication on the robot itself or do I need to write a Karel script to do this?

    And I am capable of doing that..

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