Cineversity

Hello

I’m creating a sort of dolly that follows a track.  I created the track, and I have a very simple prototype of the wheels.  To have the wheels follow the tracks as it rotates in a circle, I used a simple constraint system.
But I was wondering if there is a “smarter” way to do this with the dynamic connectors?  I will have to create a platform on top of the wheels, and I wonder if it makes sense to somehow create a more flexible system?

If constraints are the way to go, then I’m on the right track

Project file here : https://www.dropbox.com/s/6g211f4q7vb66hm/RailLight.c4d?dl=0

Hi Alex,

If it is a circle, a center Null could be the Parent and it rotated anything below it. With the Rotation angle, anything can be defined.
Does this that sounds good? I’m happy to check out the simplest solution for that.

Here is an example file, with two speed calculations, as the inner and the outer wheel have a different distances to travel. I made the wheels large to show the effect. The radius of the inner wheel is connected to the outer. Just adjust the radius [disc.out] and the P.Y (P.Y for both – in and out, but you can as well connect those)
Scene file [01]
https://www.amazon.com/clouddrive/share/Fpo8rnwd1j8MQNfbif50ms9T5r2O6ItbOWo1gBZWZkk

A very simple set up, yet my favorite is based on the length of the MoSpline. Even an back and fore will affect the rotation of the wheel perfectly.
Scene file [11]
https://www.amazon.com/clouddrive/share/t10XG0oORp31v1I4tzpAfZUAHKDp3ILkBSlpaxntruN

To have an un-even track, here is an example: [21]
https://www.amazon.com/clouddrive/share/JQJT6JTOZH20H96NOu19V4XAmNxFe2FSwCJ62yMZyk4

To keep a vehicle normally on a track,  I do it with a target tag, whereby the target is a position (Null) in distance on the same spline, and the up vector is the parallel spline (Another Null). If the track is a closed spline, the Null that is a little bit ahead, needs a different Offset, instead of 0% to 100, it needs 5% to 100% to 5%, example here: (move one of the circles to see the effect how it really works)
https://www.amazon.com/clouddrive/share/DXdaK8KONAQnEbvLYLyLsrPdKbW9ksynLJ1YSbJoGAh

If the file was more an example, please advice what details are needed.

Cheers

Edited 10:10pm PST

Hey Sassi

No this is really perfect!  Thanks a lot for sharing!
Super interesting techniques.

The only thing I wasn’t clear on was the math in the first file…Why are you multiplying the circle radius by 6.23?

Thanks!

Thanks a lot for the feedback, Alex, very nice of you!

It should be 6.283, I can’t find it in my scenes as a 6.23 entry (if so, it is nonsense. Correct is 2*3.14…)

Type in any field that can hold numbers 2*PI and you get the shortened version as 6.283, radians. Cinema uses sometimes 2PI for 360º
If you take a look into file …–21.c4d, there you might miss even that; As the result needed it one time as *2*PI and on the end as /2*PI, so I could leave it out completely. Hence the super simple and short set up.

All of these examples are just independent examples. If you need something else, please let me know: I’m happy to look into it.

All the best

P.S.: example rad vs deg here:
https://help.maxon.net/us/#GVDEGREE