Trinet Wrist Kit

The Trinet Wrist Kit combines a head camera with a camera on each wrist. The cameras share a clock over a short-range radio link, start and stop together, and stamp every frame on one common timeline — so the view from your head and the close-up views of both hands can be lined up frame by frame.

Each kit camera needs a small radio-beacon adapter on the back (sold separately).

The adapter is removable — keep it attached for kit recording.

Radio beacons are sold separately

Every camera in a Wrist Kit needs a radio-beacon adapter attached — it carries the wireless sync between cameras. Beacons are sold separately; contact us to order. A camera used on its own doesn't need one.

Spec sheet

Collecting with a stereo head camera and two wrist cameras? See the one-page Stereo + Wrist Kit spec note.

How it works

• Factory-paired. A kit arrives already paired: power the cameras on and they find each other.
• One button starts the whole kit. Press the button on any camera and every camera in the kit starts (or stops) recording together.
• One timeline. Cameras keep their clocks aligned to within 1 millisecond of each other while recording. Each camera records to its own memory card.
• Robust to dropouts. If the radio link drops mid-take, every camera keeps recording on its own and re-aligns when the link returns. Nothing is lost.
• Kit-wide protection. If any camera needs to cool down, the whole kit pauses and resumes together. If one camera's card fills up or is removed, the kit stops together so takes stay matched.
• Mixed cameras. Mono, Stereo and Stereo GS cameras can be members of the same kit.

Setting up and pairing

Kits are paired at the factory. To pair cameras yourself, re-pair after replacing a camera, or remove a camera from a kit, see Set up a Wrist Kit.

Recordings from a kit

Each camera writes its own files to its own card. Takes recorded together share a kit prefix (grp…) in their file names, so the matching files from each camera are easy to group. The Python toolkit can play kit takes side by side and verify their sync — see View a kit take in sync — and the wireless UTC tool can place every take on UTC time.

Watching a kit in the field

With firmware 0.5.9 or newer, every camera broadcasts its recording status over Bluetooth. The Trinet app's Wireless status screen shows each kit and camera — recording or idle, card present, take number, model and firmware — and can alert you if a camera stops unexpectedly. The app only listens; it never connects to or controls the cameras.

Accuracy

Measure	Typical
Motion data to video, within one camera	Sub-millisecond
Camera to camera within a kit	Under 1 ms (measured: typically about 50 µs — validation report)

For the first one to two seconds after a take starts, cameras that are still locking on can be less accurate; trim the first seconds if you need the tightest alignment.

In a kit, every camera records at about 29.7 fps instead of 30 — on purpose, so each camera can hold its frames in step with the kit's master camera. A camera recording on its own runs at 30 fps. To check a take — frame drops, frame rate, sync — see Check a recording or kit take. More in Timing and sync.