Collision bounds for gears.

I am new to this so forgive me. I have two gears sitting on a plane and want to turn one gear and have it accurately affect the other. I used the add-on
for the gears. I have them both as Ridged body. I have set the bounds as triangulate for best accuracy. I have also locked out all the xyz transformations and all rotations except around the z axis. I have set up my left arrow key to turn one gear. I have played with everything mostly the collision bounds but my gears won’t play well together. No matter what I do they still go through each other a bit and jump. I know blender is powerful but am I asking to much of it. I tried to find a tut but they are all about animating when it comes to gears. Thanks for any help.

Try modifying the physics substeps and steps (in the world panel, assuming that you’ve the engine set to Blender Game)

Thanks agoose. I have been trying this and it made a huge difference. I will keep tweaking and thank you so much.

It’s a pleasure. Be aware that the max steps is the value that keeps the physics close to “realtime”. The substeps on the other hand are closely related to the precision of the simulation. The higher the value, the more precise, and more expensive to process.

I’m curious, do you actually have to simulate the gears with physics? It would be pretty simply to just compute the correct rotations for the gears based on their gear ratio.

Here you go
Here is my own take on the situation :slight_smile:


RigidDemo.blend (1.08 MB)RigidDemo (2).blend (939 KB)

if I want to test a real world system I would use physics, if you want to make something as an in game asset, I would just use python to set up the property “rotation” and then have the rest use copy property and then apply the change or not using logic

So if I am touching you, and you are spinning and have enough torque to spin the rest that I am touching… then I can spin,

this can get VERY complicated quickly,

Not sure if someone already said this, but if you’re using “rot” in the motion actuator, it isn’t affecting the object’s angular velocity, but rather its orientation… Thus, it is simply setting it to a new rotation, and thus possibly overlapping it with the other gear. Try using “angular velocity” rather than the “rot”… Also, using a triangle mesh means that the gear’s collision bounds are made up of planes based off the faces… Thus, it’s technically hollow. You may have a better result using a compound mesh- that is, a cylinder at the center and boxes for the teeth of the gear. This will have fewer collision glitches and will actually run faster on a larger scale. Good luck!

Guys I really appreciate the help. I will be giving all these suggestions a try today. The help on this forum is second to none. I tried getting help on the forum and people do not respond to anyones post there. Thanks again.