I’ve seen a few kendo videos on youtube using GoPro or Contour cameras. This tutorial will show you how to attach the GoPro camera to the tsuki flap.
You will need a:
Take ends of the vented helmet strap and cross over behind the tsuki flap in between the flat portion at the back. Thread the ends on opposites sides and clamp it down. I place the mount as close to the mengane as possible. Then I tuck the loose ends behind the flat portion of the flap. It was a little loose, so perhaps a little duct tape to tighten it up.