# CHANGE HEAD ANGLE.

**URL:** <https://tech-community.robotics.abb.com/t/change-head-angle/4399>\
**Category:** RobotStudio\
**Created:** [September 9, 2011, 3:15pm UTC](https://tech-community.robotics.abb.com/t/change-head-angle/4399 "2011-09-09T15:15:44Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Les](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@Les](https://tech-community.robotics.abb.com/u/Les)\
**Post date:** [September 9, 2011, 3:15pm UTC](https://tech-community.robotics.abb.com/t/change-head-angle/4399/1 "2011-09-09T15:15:44Z")

</div>

I use my robot to mill plastic with a milling spindle attached to the end of the robot. I need to change the angle of the spindle as it does one of its cuts. I can do it by eye but that’s very unscientific. How do I adjust the angle by a fixed amount in a particular direction for the TCP when milling in a pre-defined work object?

---

<div class="post-metadata">

**Author:** ![PerSvensson](https://dub1.discourse-cdn.com/flex005/user_avatar/tech-community.robotics.abb.com/persvensson/32/1040_2.png) [@PerSvensson](https://tech-community.robotics.abb.com/u/PerSvensson)\
**Post date:** [September 11, 2011, 3:43pm UTC](https://tech-community.robotics.abb.com/t/change-head-angle/4399/2 "2011-09-11T15:43:39Z")

</div>

Take a look at RelTool

---

<div class="post-metadata">

**Author:** ![Les](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@Les](https://tech-community.robotics.abb.com/u/Les)\
**Post date:** [September 12, 2011, 10:46am UTC](https://tech-community.robotics.abb.com/t/change-head-angle/4399/3 "2011-09-12T10:46:58Z")

</div>

Thanks very much. I tried this and although this gives us an angular movement of the TCP… the angles are relative to the Tool whereas I want to do the TCP angular movement in the XYZ relative to the Work Object it is operating in.

So as I cut my product, moving my TCP from A to B, I want to change the angle of my TCP relative to the XYZ orientation of the product not the Tool as the Tool may be in any orientation.

Is this possible?

---

<div class="post-metadata">

**Author:** ![Marcel](https://avatars.discourse-cdn.com/v4/letter/m/71e660/32.png) [@Marcel](https://tech-community.robotics.abb.com/u/Marcel)\
**Post date:** [September 12, 2011, 1:46pm UTC](https://tech-community.robotics.abb.com/t/change-head-angle/4399/4 "2011-09-12T13:46:09Z")

</div>

Hi

A rotation with a workobject or with PDispOn doesn’t seem to be a good idea because it rotates a coordinate system around just one position. You have to rotate at every robtarget. Maybe you could read the actual orientation of a robtarget with EulerZYX, ad the value for the angle and calculate the new orientation with OrientZYX. You could even put this in a function that would do the calculation like Offs() or RelTool() does.

Best regards

Marcel