Crawler Tracks excavator fixed under carriage

[dynamicboy]

I am proficient and do understand the principles and concepts of the crawler tracks. I have carefully read all the documentation and searched the forums before posting.

I am attempting to create an excavators tracks. Unlike a tank which has suspension, an excavator has a fixed undercarriage. If an excavator travels over an object. The bogeys and tracks remain fixed and when the vehicle reaches the fulcrum the undercarriage pivots on the centre of gravity.

I have tried every conceivable option to replicate a fixed undercarriage and was hoping someone can point me in the right direction?

Thanks in advance