animation help

[Anonymous]

Hi All,

I wondered if someone could explain how to model/animate something for me. I have a motorbike wheel and want to model an arrow that represents gravity. I have animated the wheel to tilt (as motorbike leans) but want the gravity arrow to stay parallel to the YZ plane as the wheel tilts. I can do this bit no problem, but I also want the arrow to start on the work axis (representing the centre of mass - see assembly attached) and end on the XZ plane (representing the ground). So this means that it shortens as the wheel tilts.

I tried to model an arrow in place and use a driven dimension to dictate the length of this arrow but it gave me a cyclic dependency error. 

I would be very grateful if someone can help,

Thanks

Jonny

[Anonymous]

I would like the arrow to copy the red line exactly as the two attached screen shots show but in an animation:

[coreyparks]

Is this what you are looking for?  Drive the "Drive me xxxxxxxxx"  constraint iin the assembly and see.

[Anonymous]

This is exactly what I am looking for - did you create the arrow completely separately or did you create in in the assembly so that it is adaptive? or do you place it, and contstrain it, then just right click and hit adaptive?

Thanks a lot for you help - this forum is amazingly helpful.

Jonny

[coreyparks · Accepted solution]

I created the "arrow" as a new part completly outside of the assembly and made the feature I needed adaptive.  I then inserted it into the assembly and constrained into place and then made the part adaptive in the assembly as well. I never create parts in place if I can get around it as projecting from one part to another seems to create nothing but problems, especially if you want to use the part created somewhere else.  Also try and stay away from tangent constraints when trying to drive adaptive parts as  it almost always seems to cause problems.