# Maintain equal rotation on multiple objects

I am making a model with gears. I want to be able to turn any gear and have the others follow. Using constraints or drives only one gear will rotate (and the other will follow). Is there anything I can do?

edit: To clarify what I mean: I don't want to use physics, I want to be able to select any one of multiple gears, rotate it and have the rest rotate too. Using constraints or drivers I am restricted to only being able to turn the one gear that all the rest are constrained to.

• Perhaps make it a rigid body object? Then you can make it a passive body so that it will affect other gears but not fall? Keyframe gravity? Hope these ideas helped! – BoyOfAwe May 28 '18 at 2:41
• Can you post some screenshots of the constraint or driver set up – Ninjabdou May 28 '18 at 3:42
• Is it always the same gear you want to turn and have the others follow? Or does it have to work for turning any gear and the remaining follow? – Yunnosch May 28 '18 at 5:56
• @Yunnosch .. now I'm interested too... how would you do your second option without creating a dependency loop? – Robin Betts May 28 '18 at 7:35
• @RobinBetts I think no matter how this is done, the one gear being rotated to drive the rest would need its constraint or driver or physics setting or ... disabled or removed. My take would be to set up an overseeing GearSystem class and use some custom property to mark objects as gears. While in "drive mode" a driver on some property akin to GearSystem.rotate(self) will drive and set all the others based on context object being the driver gear. – batFINGER May 28 '18 at 9:34