Trajectory animation


(sk) #1

Hi,
I wanna make like this trajectory animation using kangaroo.
Is it possible?

thanks


#2

It might be possible, but not very straightforward. What are you trying to get out of it? Simulation of a certain motion or a nice animation or something else?


(sk) #3

Thanks,

I wanna an assembly simulation. In Kangaroo, we can assemble and then moving with a Grab component(http://www.grasshopper3d.com/group/kangaroo/forum/topics/mechanical-assembly-simulation-tutorial-videos-and-examples), but I want to do it on a trajectory.


(Daniel Piker) #4

follow00000

assembly_pathfollow.gh (29.9 KB)

Hope this helps.

I’ve used pairs of shared points to create the hinge constraints between the pairs of solids, the blue part is locked to only allow rotation about Z, and the green part has an additional point anchored to a moving point on the curve.


#5

That is actually quite straightforward. Just out of curiosity, is it possible to limit the range of motion (e.g. rotate around Z in a range of 0 to 90 degrees)?
And how would such a setup respond to overconstrained/impossible relationships?


(Daniel Piker) #6

To limit a range of motion you can use the ClampAngle goal on a pair of lines, and attach the points of those lines to the rigid bodies like this:
body_clampAngle.gh (22.8 KB)

I can see though that perhaps it would also be useful to have another way to limit angles directly between a pair of solids.

Because it is using relaxation to solve the constraints, underconstrained or overconstrained setups aren’t a problem.
If underconstrained and there are many possible solutions, it will just go to a solution closest to the current
one.
If the setup is overconstrained, or there is no way to satisfy the given constraints simultaneously, it will find a compromise minimising the sum of squared errors. If you want one constraint to be enforced more strongly than others, you can increase its relative strength/weighting value.


#7

Cool, thank you for taking the time to explain this.


(sk) #8

wow amazing. this is actually what i want. thank you !