Digital Head Avatars for combat helmet fit

Today’s combat helmet is becoming more than only a means to protect the warriors head. It is increasingly also used as a platform for sensors and has to integrate with other protection devices. As such, the combat helmet is becoming an integrated system with higher demands on combat helmet fit and stability. Combat helmet fit is usually tested in time-consuming field trials. This paper describes a study on the use of digital head avatars for combat helmet fit testing in the quest for less time-consuming trials. A family of seven digital head avatars with various head dimensions was selected from our database of 3D whole body scans of the Dutch Military Forces. Multiple head dimensions were used to select these seven head avatars, which were than printed in 3D. Different helmet configurations were placed onto the resulting digital head avatars (DHAs) as well physically on a set of subjects (male, n = 29) with comparable head dimensions, following the manufacturers guidelines. Each subject and head avatar was scanned with and without the helmet. After digitizing these helmet configurations, the orientation and position of each helmet was analyzed using 3D CAD. The results revealed that the helmet orientation and position was the same for the real subjects and for the DHAs. Hence, the use of helmet fit testing on DHAs has been validated, which opens the path to use DHAs for combat helmet fit testing. Currently this method is applied in the replacement of the Dutch combat helmet. A family of high resolution DHAs was constructed using the 3D head scans from subjects. The family of seven DHAs represent 95% of the Dutch soldier population. These DHAs are used to analyze each helmet fit in a digital manner as well as in a physical manner (using 3D printed versions). Thus it partly replaces field trials with the focus on helmet fit, other aspects such as thermal comfort, pressure points, compatibility with government furnished equipment still has to be evaluated in field trials.