Cineversity

I’ve dropped a cogwheel into my scene. Is there an easy way to lay the teeth flat, so it’s essentially a line of straight teeth and not a round cogwheel?

Hi mattrittman,

Please use the Legacy Mode check box for that.

Let me know if there is anything else.

All the best

P.S. If the hole and the Inlays are part of the target, please have a look at the file below.
https://www.amazon.com/clouddrive/share/gdugsFBxE1nxPkT2Kjumvb4tv17P01zdlY50kxuJTcR

Thanks Dr. Sassi, but this is what I am talking about.

Thanks for clearing it, mattrittman!

A rack-and-pinion gear , or more precise a rack-gear that works for your cogwheel.

Please have a look at the files below: (one zip, two scene files)
https://www.amazon.com/clouddrive/share/s6KsJwNYLdpkcD823S1j2odUoJNraefuN4IDlXA9bJD

There is no direct way, to get a rack-gear spline from the given tools in C4D, perhaps the Formula spline, but I have no idea at the moment what formula I could create to make it fit to the options given in the cogwheel.

I have to dig a little bit deeper…

My best wishes

P.S.: “I have to dig a little bit deeper …”, was what I mentioned in the post above.

The teeth of a cogwheel (pinion) while rolling describe a larger space than they have while standing still. Which leads to a none working set up when the teeth become too long, and/or, too tight.

Having said that, please have a look at the file below:
https://www.amazon.com/clouddrive/share/YeQyuhCIfQoHBO0uhZmW2NqWU1lMyse0d7dnDPYoOnM

Press play and change carefully the parameters of the cogwheel in the scene. For each point of the spline, one frame has to be played. Each frame, the cogwheel is explored 0.1% and then the next.

Animation>Play Mode> Simple, if played from frame zero, it stops then on the end, the “Spline0-1000” object can then be copied/saved and used. It should be a close fit to the cogwheel, Scaling a little bit perhaps is needed.
A short and quick overview is screen captured here: (one minute)
https://www.amazon.com/clouddrive/share/N98F7RLZUnqKkx8OS8gp43HDlzKf5DgiqA63alLKQhC

When done, uncheck the Xpresso “enabled” checkbox.

As a side note, I had first a continuously rotation as exploration of the cogwheel, which distorted the shape. If you observe the Platonic object closely, you will see that it rotates slow, then fast, then slow, that finally allowed to explore the round wheel close enough to create the straight one.

Enjoy

P.S.: it is easier with an editable cogwheel. Scene file
https://www.amazon.com/clouddrive/share/MEyIyydwTdfEduDspmYd8lfC9IUQtMoRSzka4HTTTIP

Yes! Rack and Pinion is how I should have referred to it, but I didn’t know the name off the top of my head haha.

Your solutions are way beyond what I would have ever imagined! Very very helpful! Thank you so much Dr. Sassi!

Thanks a lot, mattrittman,
I had to look up this term as well, so far here in the US I haven’t even heart it in over a decade by now.

I have always the feeling, there must be something simpler or more intuitive, perhaps just something procedural…

The procedural below, I would call that, “Spline2Ani2Spline”, utilizes a simple but very effective option to convert splines into position tracks.
First we need a single element, the point number sets the needs for the frame number. Functions> Spline to Position Track

The Y value can be just repeated, the X value needs to be: Offset Repeat. Since there is no Z change, I deleted that track.

Now we have a direct option to use these position tracks to create a spline, or we can use MoGraphs Tracer for that, which might allow for some adjustments, point wise etc.

The pure Timeline creation (one minute screen-capture)
https://www.amazon.com/clouddrive/share/gqv9v2P14aXZsjhi8FulOQOylmXmPtSA75fZwxtX4Dx

The MoGraph Tracer version (one minute screen-capture)
https://www.amazon.com/clouddrive/share/mJ08bdFUwFxOSqde32SMqhvVhMj1MGHVT2z9LG6kgOF

Have a nice weekend

P.S.: I was looking for a formula which could work with the Formula Spline.

Here is a little Rack Maker.

Scene file and a one minute screen capture:
https://www.amazon.com/clouddrive/share/kCgYQogFhulEpOgArbsyF5DdTDT9IFvwsHHQfYVISY0

Later, perhaps, adjust Tmin and Tmax to your liking, i.e., for the final length.

Enjoy.

Oh wow, I really like the Rack Maker you’ve made! It would be pretty cool if something like this was built into the Cogwheel object! Thanks so much Dr. Sassi. You sir are a genius.

You’re very welcome, mattrittman!

Thanks for taking the time.

Yes, a default function for that would be nice.

Cheers.

Matt, as mentioned above, the Rack needs to be based on the rolling movement of the cogwheel, and this results typically in more space than the teeth itself.
The idea was to find the simplest set up, to create something like a “Rack Blueprint Maker”

Please have a look here:
https://www.amazon.com/clouddrive/share/0f3V7JuYa9rmBbyCjehoc9Nz2LC1WtZSJx3YQz6nZG6

If you change the cogwheel configuration, please wait one “scene-time-play-duration” until it’s done. Preferably: Animation>Play Mode> Simple

Here is a screen capture of the adjustment after the cogwheel has drawn its “Ghost”:
https://www.amazon.com/clouddrive/share/MDQriVYAevNKi2eMQigpyBP9S9lg47r5fLgYcGCwxoY

You might adjust it as needed, where the pressure point of the combination is and where a little gap is left on the other side (in the example file the pressure-point is on the right side). The result of my quick set up is here:
https://www.amazon.com/clouddrive/share/IzzZqNZfG28WO8OzYEgk80Fl4bpsUFgFqXGkRb4ShBn

If a longer (or shorter) Rack is needed, adjust later on the T values of the Formula Spline.

Enjoy

Oh wow using a Tracer object on the cog is quite clever! It really draws the exact configuration you’d need for the straight teeth. Haha I wish I was as smart as you Dr. Sassi! This is very helpful. Thanks again!

Thanks a lot, you’re welcome Matt, very nice of you.

My idea about creativity is, that it is the ability to connect unrelated things with each other, and after connecting such things, some of those will make sense in an before non-predicable way.
To do that, one has to fill his/her creative library: Playing, messing, exploring, taking apart, trying to break it, do anything agains the rules (i.e., art rules—not including law of course), etc.
Having a constant growing library established, we need then only to overcome the “That’s how it’s done!” and the even more horrible “I know that!” behavior, and arrive so at the “What if…” state. Anything else will works wonders after that. (…mostly!)

ENJOY.