why my system is not functioning properly?

My task is to run stewart platform on a moving base. So I choose to do it in the following way. But I dont know why the system is falling and balancing is not done properly. I have reduced the weight of the system also thinking of iit may be due to weight. Can anyone help with it ?

[Yifeng Tang]

You model requires a "StewartPlatformLibrary". You may want to include that.

[Walter Roberson]

StewartPlatformLibrary is perhaps from https://core.ac.uk/download/pdf/322824733.pdf