Good ! Thank you for your reply.

It works quite well by adding this system to both sides.

moving_on_surface_2.c4d

I'm creating a new post.

So I found a solution for movement on the tank on a surface; with ray collision, I have more freedom of movement. I've attached the file.

https://we.tl/t-SIrv1LYYH9

Good i understand, thanks you very much !

I have another question. I created a tank rig (I've attached the files and a video to explain). I'm using a mesh with Deformer Shrink Wrap on a surface the tank drives on. I'm using a Matrix to retrieve the positions of the mesh points, and the average of these point positions orients the tank on the surface. But the problem is that it doesn't follow the surface very well. Is there a technique to make an object perfectly follow a surface like the red cube? As if it were actually colliding with the surface.
https://we.tl/t-RyuQlPtrag

Yes, of course, it works better with the previous global matrix. thanks you

I managed to create a fairly simple system where I calculate the distance traveled and then use it for wheels and tracks
track.c4d

Good Thank you for the explanations.

Interesting the goal is to be able to automatically rotate wheels or tracks based on their size and the vehicle's orientation. I acquired a tank rig (I've attached the C4D file). I isolated the Xpresso function that handles the wheels and simplified it. As a result, the wheel rotates perfectly according to its size, the distance traveled, and the orientation. And the wheel's rotation value doesn't reset to 0; it accumulates simply by moving the controller in the interface. The problem is that I don't fully understand how Xpresso works. I don't know if it can be simplified even further.

WHEEL.c4d

Hi
I'd like to know how to add and accumulate values ​​in Xpresso. For example, I have a moving Null, and using the Distance node, I get its distance traveled each frame. I'd like to be able to accumulate each value at any given time to increase the gauge. Furthermore, I'd like to be able to increase the gauge even when there's no animation, when I move the Null within the interface. How can I do this?DISTANCE.c4d