Cycloidal Rotors - Help

[EMKshadow]

I'm trying to make a pair of cycloidal rotors that have mathematically correct dimensions for a project. I have a mechanism that uses tracers to outline the rotors perfectly but i need to turn that into a polygon. I traced the tracers into a polygon which didnt turn out to well and anyway if anyone has any ideas how this could be done i would gladly accept any thanks!

[scene]51173[/scene]

[TC42]

My only suggestion is to use CSG to make the lines smoother. And use circles scaled to elipses to get different curves. I was just thinking about how there should be a tracer-cut option in algodoo... You probably knew all this already, am I right?

[Someone Else]

Hmm...

Well, I can very easily make a very accurate cycloidal gearset IF:
The actual cycloid gear is a ring gear,
and the pin gear has half as many teeth.
And there are few options as to how many teeth it can have.

It's easy because the pins travel in EXACT STRAIGHT LINES relative to the ring gear.

How do I know this?

Check out theWoodgears Gear Generator Program.
The Eval version certainly works, but the output is distorted. I never tried saving a gear with it, but I severely doubt that would be a suitable loophole.

And I think you can save a gear as an image, so you could Photoshop it so that the gear is opaque and the rest transparent, import it into Algodoo as a texture, put it on a circle (so it is not distorted), Generate Geometry from Texture, Clear Texture. Then, you may need to find some way of clearing pixellations that may or may not exist. CSG-subtract boxes and circles. Without the grid.

[TC42]

Wow, Someone Else, I didn't know you'd heard of MatthiasWandel as well

[EMKshadow]

TC42, i tried some csg to make some parts of it but its a VERY abstract shape and Someone Else, how can you generate a geometry from a texture cause i've never heard of that. And im trying to make these scale properly in algodoo and i'm not too sure if a texture will scale properly. the main circle is 4m in diameter and the hypo and epicycloid making circles are 1m in d. so if i make it completely in algodoo it will be very useful. I just had an idea to make a square around the tracing and use MANY circles around the trace to csg it out that way which i think will work. I'll keep it posted

[Someone Else]

To Generate Geometry from Texture:
Make a geom of any sort- Box, Circle, or Polygon. It does not matter.
Go into Appearance Menu, Find Texture, Algodoo or Algoryx. Or any texture you have built that has some transparent part.
Go back to the Appearance Menu.
Click Generate Geometry from Texture.

Can't get much simpler than that.

EDIT- If you put the texture on a circle, it should scale properly, provided the original image is a square. I think. I don't see why it wouldn't.

And, with the circle thing (if I understood you right), you will need some way of smoothing out the final product.
Or, you might want to SPAWN the circles that will later be CSG-subtracted.
Maybe put this into the onHitByLaser of a laser that hits a box at the center of the tracer. The code is probably faulty, though.

Code: Select all

scene.addCircle {
   radius := 1;
   density := +inf;
   collideSet := 0;
   pos := e.pos
}

Make the radius := whatever the radius of the pins is going to be.
The code will spawn a circle with a radius of 1 meter, infinite density (so it cannot move), that will not collide with anything, at the place where the event happened- where the laser hit a box, where the box got hit by a laser, or where the box hit something else. It all depends where you put the code.

Oh, and set the maxRays of the laser to 1. This will prevent the laser from bouncing anywhere.

[EMKshadow]

wow i never knew/done that before. anyway i did the circle thing and it worked very nicely thanks for the info/help both of you :