[Question] Question title：Building and rotating the rubik's cube model in isaac sim

[xzhenxiao]

Question

Hi there,

I am trying to build a rubik's cube in Isaac Sim. A 3*3 Rubik's Cube has 27 small cubes, the center one serves as the base, the other 26 cubes are connected to it with spherical joints. When rotating a layer of the rubik's cube, I want to drag a small square, and use collison to drive the other small squares in this layer to achieve the rotation of a layer of the Rubik's Cube. The mass of each cube is 0.03kg. With disable gravity, the rubik's cube rotates easily, but with gravity , even though the mass of each cube is set to be very small, if I drag a cube, the layer will not rotate at all. if I use a large force, the rubik's cube will be pushed away, I would like to ask how to make a layer of the rubik's cube turn smoothly under a force, and why it doesn't turn when gravity is taken into account?

Thank you in advanced!

[RandomOakForest]

Thank you for posting this question. I will move it to our Discussions for the team to follow up.

[StrainFlow]

I would take a look at your friction values next. Are you building the cubes to have a manipulator try to solve them? If that's the case spherical joints should be fine, but you can't have spherical joints in an articulation.

[xzhenxiao]

@StrainFlow Yes， I am building the cubes to have a manipulator try to solve them. I first create a Rubik's Cube with spherical joints and the joint friction of 0. Then I create the environment and load the Rubik's Cube as articulation into it. The spherical joints are automatically split into revolute joints around xyz. If I don't load it into articulation, how do I load the Rubik's Cube?

[StrainFlow]

I haven't tried this myself, but you might be able to load it as a rigid object and keep the spherical joints?

[xzhenxiao]

I will have a try， thanks.