1. Hardware and wearing

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1.1 Bill of materials

Part	Model	Qty	Where to buy	Notes
Body trackers	VIVE Ultimate Tracker (with wireless dongle)	5	Taobao	Camera-based tracking, no base stations
Head camera	GoPro HERO13 Black	1	Taobao
Media module	GoPro Media Mod (HERO13/12/11)	1	Taobao	Provides the micro-HDMI output
HDMI capture card	UGREEN 4K60Hz USB capture card (UVC)	1	JD	Shows up as /dev/videoN on Linux
Video cable	micro-HDMI to HDMI	1	JD
Gloves (one of)	MANUS Metagloves Pro	1 pair	MANUS website; contact their sales team	Finger articulation only
	Wuji gloves	1 pair	Wuji website; contact their sales team	Finger articulation plus 24 × 31 touch per hand; Ethernet
USB Ethernet adapters	UGREEN USB 3.0 gigabit adapter	2	JD	Wuji rig, one port per glove
Straps	VIVE tracker straps, GoPro head strap	1 head strap, 4 straps	Tracker straps · GoPro head strap
Linux capture PC	Ubuntu 22.04 or later	1	—	Wuji rig only; a portable device works
Windows PC	runs SteamVR	1	—	Trackers only on the Wuji rig; the whole capture on the MANUS rig

1.2 3D-printed parts

STL files and print settings go into hardware/3d_print/ of egoexplorer-toolkit (in progress).

Part	Purpose	File	Qty
Head adapter	Couples the GoPro rigidly to the head tracker and mounts both on the head strap	gopro-tracker.stl	1
Hand base	Holds a tracker on the back of the glove	wuji-contact.stl	2

1.3 Tracker roles

Each tracker gets a role in SteamVR. The capture program, the pipeline and the released data all use these names:

SteamVR role	Name in the pipeline	Where it is worn	SMPL-X joint
camera	head	Head, rigidly coupled to the GoPro	15
left_wrist	left_hand	Back of the left hand	20
right_wrist	right_hand	Back of the right hand	21
left_ankle	left_foot	Outer side of the left ankle	7
right_ankle	right_foot	Outer side of the right ankle	8

Left and right always mean the wearer's own left and right. Facing the wearer, their left hand is on your right. No step may swap roles according to the left and right of an image.

The head tracker and the GoPro are rigidly coupled, so the camera pose comes straight from the tracker and does not have to be estimated from the images afterwards. This only holds if the two never move relative to each other: tighten the adapter and keep the head strap snug. If the camera is knocked during a recording, its pose is no longer usable for that recording.

1.4 Putting the rig on

Two people work best: one wears the rig, the other checks.

1. Measure height and arm span (for a new person or before recalibrating). Arm span is middle fingertip to middle fingertip; measure each twice and average, and enter them in metres at calibration. Other measurements (shoulder width, upper arm, forearm, hand length) can be recorded for reference.
2. Put on the gloves and check the sides. Wuji gloves are told apart by serial number; confirm on the capture page that each hand shows on the correct side.
3. Mount the hand trackers. Place the base in the middle of the glove's back and strap it so the tracker does not wobble when the wrist moves. The left hand carries the tracker with SteamVR role left_wrist, and likewise on the right.
4. Mount the ankle trackers on the outer side of the ankle, above the ankle bone, tight enough that they neither turn nor slide when walking or squatting. Mind the roles.
5. Put on the head strap, head tracker and GoPro. Adjust the strap so nothing moves, with the camera pointing along a natural forward gaze.
6. Take two mounting photos (front and side); they help check tracker positions and orientations if something goes wrong.
7. Check while standing still. The wearer stands naturally for a few seconds. On the capture page, confirm that all five trackers are online without jumps, both gloves stream data and the video shows a picture (the page is shown in 3.4).

1.5 Wearing rules

These rules decide whether the data is usable

• Calibration and task recordings must come from the same donning. After removing a tracker, a slipped strap or a change of wearer, record a new calibration (chapter 5). A changed mounting cannot be corrected afterwards.
• Do not adjust trackers between tasks. Each donning has one set of mounting parameters.
• Sides must match the SteamVR roles. Swapped trackers make the SMPL-X solve fail.
• Keep the straps tight. A tracker that slowly slides looks normal frame by frame, and the error is quietly absorbed into the body pose.

Wuji touch. The gloves' touch sensitivity drops slowly with use, and some lines become intermittent. Run a touch calibration in Wuji Studio (about 15 seconds) once a day before capturing, so the glove's condition can be tracked.