Author Topic: Tool direction on surface  (Read 4911 times)


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Tool direction on surface
« on: July 23, 2014, 03:47:47 PM »

I need to scan the surface of a cylinder with a sensor mounted as the tool on a Kuka robot. I have defined a cylinder and used the Kuka PRC SRF ISO block in Grasshopper to define a toolpath. However, the yellow tool lines are all pointing from the surface toward the centre of the cylinder causing the robot to scan inside the cylinder. I need these lines to point out from the surface - how is this best achieved? I am not clear on the ORIENT input of SRF ISO - hows does the location of a point attached to this input affect the toolpath? Should I be using a guide curve for this toolpath?

Johannes @ Robots in Architecture

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Re: Tool direction on surface
« Reply #1 on: July 24, 2014, 12:19:05 AM »

ISO-SRF takes the normal vectors of a surface. If it is facing inside, you have to flip the normals of the surface, either in Rhino or in Grasshopper.
Regarding Orient: ISO-SRF takes the tool tip from the surface and the tool vector from the normals. Due to the robot's 6 degrees of freedom it can also rotate around the tool axis itself. Orient defines towards which point (around the tool axis) the tool is facing. Usually a good position for the Orient point is somewhere close to the robot's "center", i.e. axis A1.

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