Ok I'll try and explain how the sensors work
I remember using these in Uni in sports biomechanics and they had the same kind of settings.
Basically you have your subject covered in a black thin material (black so it doesn't appear on anything, and thin so that the sensors are as close to the skin and joints as possible).
The sensors are attached to the joints of the body, mainly attached to the joints that will be in use (considering they were recording his whole body's movements he had them all over his body).
There is a green screen used as a free background, just like they've been used for years for the weather reports etc.
There are like little towers positions at different right angles of the designated "stage" these towers have high speed powerful cameras that pick up the movements of the little sensors and send their recieved signals to a computer. The computer then records each sensors motion in a timeline.
These can then be stored, viewed and then combined together to move a designed model graphically created.
So basically they record the motion of the sensors, and attach the variety of motions to a variety of designed objects.
They would have designed the skeleton digitally and then given it the instructions recorded from the sensors to make it do what was needed.
then once the skeleton was perfected it's layered over the filmed segment with the background actors and set.
Hope that helps more?
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