Solver Configuration error in simpscape multibody

Could help me I have the following warring when i'm trying to run simulation:

An error occurred while running the simulation and the simulation was terminated

Caused by:

['untitled1/Solver Configuration']: Model not assembled. The following violation occurred: Position Violation. The failure occurred during the attempt to assemble all joints in the system and satisfy any motion inputs. If an Update Diagram operation completes successfully, the failure is likely caused by motion inputs. Consider adjusting the motion inputs to specify a different starting configuration. Also consider adjusting or adding joint targets to better guide the assembly.

[Alex]

I'm not interested in opening an unknown zip file. So please describe your project by posting a picture of the model and by giving details of the individual parts.

Answer 1

[Yash]

Hi Max,

I understand that you are facing the "Model not assembled" error while simulating a Simscape Multibody Model.

The error indicates that the issue is either with assembly of joints or with the motion inputs. The first step to debug this error is to Update Model Diagram (You can use the shortcut Ctrl + D). If the Update Diagram operation completes successfully, the failure is likely caused by the motion inputs.

I downloaded the model you provided and performed the Update Diagram operation, which completed without any errors. Upon examining the motion inputs, I noticed that there are three sine wave inputs in the model, as shown below:

This usage of the Sine Wave block is unusual since both the Bias and Amplitude are set to zero. Consequently, this configuration produces a constant zero signal, resulting in the error you encountered. To rectify this, I modified the Bias to 4 and the Amplitude to 1. After making these adjustments, the model executed without any errors, and the motion was visible in the Mechanics Explorer window.

However, note that it only works for a very few values of Bias and Amplitude. As it is a very complex model, I can not provide the exact reason for these limitations just by looking at the model. I recommend examining the motion input logic and implementing the model accordingly.

Hope this helps!