Help with Simscape Multibody

An error occurs when creating a diagram in Simscape Multibody.

Initially, when creating the diagram, I took into account the location of the coordinate systems of each body and added a Rigid Transform block for the correct operation of the system.

Figure 1 highlights the problematic branch where I cannot identify the error.

Figures 2, 3, and 4 show a hydraulic cylinder model (sleeve and piston rod). I specified a Revolute Joint and Rigid Transform to position the cylinder in the frame (based on the original 3D model). I did the same with the piston rod, placing a prism-type joint between them. Everything is aligned according to the model. The coordinate system of the piston rod end and the end of the cylinder's internal cavity are aligned along the coordinate axes, but Simulink still returns an error.

I would be grateful if you could help me solve the problem and suggest how to avoid them in the future.

[Yifeng Tang]

The file solids are imported and assembled manually into Multibody, is that correct? I wonder if CAD->Multibody export would do a better job, assuming you are using a CAD tool that has a multibody plug-in (link).

If you have to do it manually, break the problematic loop, and place a transform sensor where you want to place the joint. The sensor output can tell you if there is a shift in position and coordinate system. That may help you diagnose the misalignment.