zlacker

It's hard to find anything about older programs, but they currently put a lot of work into simulators.

https://www.nasa.gov/sites/default/files/ivv_grubb_nasa_ivv_...

On the other hand, at one time there was a physical "proof test model" of the Voyagers.

https://www.jpl.nasa.gov/images/pia21734-voyager-test-model-...