This may sound simple, but I have a model with cog wheels on it. I want to be able to make the cog wheels turn around their own wheel axes using a simple expression ($F/50, for example)in the “rotate” param of tranform SOP. I have tried positioning the transform handle through toggling as to match wheel's own axis, but once I animate the wheel it only does so along the world axis.

What may be complicatin things is that I am using the object in a sequence blend SOP.


Again, the cog wheels are a part of the bigger object at the SOP level.

I hope it all makes sense… 8)

look in to the transform axis sop. you can set an axis for the model to rotate/translate/scale on. since you are dealing with one axis and one rotation parameter, you would want the axis projecting as a normal of the cog so that it rotates correctly. you can put your expression in there as well.

hth,

dave

p.s. to ensure accuracy, i would display your cog's normals and scale your normal's display in the misc tab of the display properties. you can then easily and accurately align the new axis to rotate on.

Awesome! Thanks. Transform Axis OP is one of those obvious operators I have hardly used….guess I forgot about it. :roll: