The Helm Mechanicum is a device used by Imperial Knight Armigers.
The Helm Mechanicum is essentially a scaled down version of the more prestigious Throne Mechanicum. Placed upon the head and connected via pre-frontal sockets to the pilot’s cerebrum, these machines do not require a full Becoming ritual in order for neural interfacing to be successful. For this reason, the prestige of piloting an Armiger is significantly less than that attached to sitting a fully fledged Throne Mechanicum. This is compounded by the fact that, while Armigers can operate independently, it is traditional for their Helms Mechanicum to be neurally slaved to the command impulses of a larger Knight, rendering them subordinate. To accept such mental serfdom is to possess the rank of Bondsman, and while this is certainly no mark of dishonour, it is far from glorious. It is for these reasons that the piloting of Armigers falls to those from the lower social strata of the Noble houses.