Helmets I designed to work with Iphone and Unreal Live Link
One has a bicycle helmet as the base and the other uses wrestling headgear. Both have counterweights at the back to balance the weight on the front. Aluminum and carbon fiber rods were used to lower the weight considerably.
I modified the Unreal Live Link Maya python script that Epic supplied to us to add some additional features and mapping configurations.
I created an importer to Maya for the csv data straight from the iphone since it meant the best data possible(no dropping of frames or data due to network bandwidth). I created the mappings for all our different facial rigs (Snappers and DIgic Style). I added the option for a custom attribute node to be inserted into the rig logic to optionally multiply the values on each animation curve so animators could tune the mocap input as desired before baking the results to the rig.
When beta testing LiveLink, I requested that Epic restore the face calibration that was dropped but supported by the Apple Arkit technology. This seemed to improve establishing a baseline for pose detection and resulted in better mouth closures and other quirkiness that seemed to happen on different face types.