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    a

    Rigid body not working

    abdulfahim83
    posted to: Exercise: Create a simple Rube Goldberg machine.

    Hey I have this issue from the beginning of the class sometime it works just fine sometimes no matter what I change it just feels same no difference. I have this setup hinge constrains works just fine but the collison is not working I tried baking with different substeps per frame and solver iterations nothing working I made sure the collision shape is mesh everything else is at default. as you see it touches the boxes but nothing happens its just like I never added arigid body can you please help me to figure out.

    Reply
    • a
      abdulfahim83 replied
      right now in the screen shot I have it baked but nothing seems to work when I delete the bake and bake it back after the setting changes. when I delete the bake the cache seems to not delete it unless I change something in the settings I dont know does it suppose to work like but really frustrating 
    • Martin Bergwerf replied

      Hi Abdul,

      What is AnimAideRT? Are you using an Addon?

    • Martin Bergwerf replied

      Also, what is your setup exactly? 

    • a
      abdulfahim83 replied
      Hi Martin that’s an Addon i found for Animation. But this set I used quick rigid addon for faster setup it is in blender extensions. Basically that ball you see in my screen shot has active rigid body and 10kg in weight. The sphere in the top has passive rigid and an empty with hinge contrains that part works perfectly fine. These  dominos kinda cubes has passive rigid body and the collision for the sphere and cubes is mesh. Basically when the sphere drops and swing around the cubes should just react to the physics of it may be some finda destruction or something. The orgin point for the ball is in the extreme top so that it can hinge properly and for the cubes is in the middle of the geometry. Right now when it swings it just penetrates and do the pendulum motion but the cubes doesn’t react at all. 
      Sorry it got too long hope I am clear if not Ill also be happy to upload my file.
    • a
      abdulfahim83 replied

      I think I figured out. Changed the cubes from passive to active. changed the collision from mesh to cubes for some reason mesh doesn't work for me in this project and finally made all the cubes longer and it starting to react to the sphere now. I thought physics would be the easiest in 3d but there are so many technicalities which makes it so much complicated. 

    • Martin Bergwerf replied

      Yes, 

      Don't use Passive for things that need to react to physics.

      Also, with simple shapes, like a sphere and 'cubes', there is no need to use Mesh as Collision Shape, not even Convex Hull if you can use Sphere and Box, because they are much easier/faster to calculate.

      Physics are not easy in 3D, as you've noticed.

    • Kenny Phases replied

      I had the same guess that the cubes either did NOT have a physics body, or were set to the incorrect type. Thank you Martin for stepping in to help!