Simulate A "pulley like" effect



I have a ball (purple, top left of the screen) that ends up falling inside cylinder A, and pushes piston A (the two empties provide a slider and a generic spring rigid body constraint).

I have been trying for several hours to obtain the following behavior : when piston A is pushed, piston B must rise and push the green ball (currently not setting on top of it, but it falls inside once the simulation in played).

It doesn't sound complicated, but i tried several solutions including object constraint (transformation), drivers... I never manage to have all the following conditions OK :
- Get the green ball NOT to fall through piston B
- piston B to rise correctly
- piston B not to wobble all around (it should be an active object).

I am not sure, but it seems to me that Rigid Body Constraints and Object Constraints do not work correctly when both activated.

How would you achieve the desired outcome ?

1 love
Reply
  • Martin Bergwerf replied

    Hi Koala,

    I am not sure how I would do that, but at least try to keep everything 'inside' the Rigid Body System. Using Object Constraints here, is likely to cause Dependency Cycles. Maybe using a mechanical connection between the 2 Pistons? I did something like that here:


    You can of course make the connection invisible. 

    And, I believe, that you can prevent the 'wobble' by Locking the Rotation and maybe even the X- and Y- Location in the Object Properties.


    1 love