What is the best practice for using Ergonomics at Work App to simulate the the movement of a product using a gravity arm?

My thoughts would be.

The Gravity Arm needs to be a kinematic device with inverse kinematic to be controlled by the handle

The manikin would then interact with the human interface on the gravity arm 

What I am unsure of it how the gravity arm then interacts with the product.

Any advise and guidance would be fantastic