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Hello, I am attempting to design an feature that exports laminate robot models to popupcad for the purpose of physics simulation. Unfortunately, the default physics engine ODE does not appear to solve the joints of the model very accurately and in fact will often cause the model to rip apart. While the physic engines DART and Simbody look much more promising, they both seem to cause "thin" meshes to fall straight through the planes. Meanwhile, while ODE solves the joints of the model atrociously, it does get the collisions correct. Any idea on how I can get this model to not fall through the floor, but still have it decently solve the joints?

A link to what happens in ODE when I try to solve for joints from a fixed reference frame, just having it hit the ground solves it much more effectively, but gaps begin to appear between the joints in the model.

Hello, I am attempting to design an feature that exports laminate robot models to popupcad for the purpose of physics simulation. Unfortunately, the default physics engine ODE does not appear to solve the joints of the model very accurately and in fact will often cause the model to rip apart. While the physic engines DART and Simbody look much more promising, they both seem to cause "thin" meshes to fall straight through the planes. Meanwhile, while ODE solves the joints of the model atrociously, it does get the collisions correct. Any idea on how I can get this model to not fall through the floor, but still have it decently solve the joints?

A link to what happens in ODE when I try to solve for joints from a fixed reference frame, just having it hit the ground solves it much more effectively, but gaps begin to appear between the joints in the model.

Hello, I am attempting to design an feature that exports laminate robot models to popupcad for the purpose of physics simulation. Unfortunately, the default physics engine ODE does not appear to solve the joints of the model very accurately and in fact will often cause the model to rip apart. While the physic engines DART and Simbody look much more promising, they both seem to cause "thin" meshes to fall straight through the planes. Meanwhile, while ODE solves the joints of the model atrociously, it does get the collisions correct. Any idea on how I can get this model to not fall through the floor, but still have it decently solve the joints?

The test model in question is shown above.

A link to what happens in ODE when I try to solve for joints from a fixed reference frame, just having it hit the ground solves it much more effectively, but gaps begin to appear between the joints in the model.

This is how ODE solves the system when fixed to the world from. As you can see, one can barely even tell they are in hinge joints.