Wearables & Sensors

Body worn devices and the sensing elements inside them: optical heart rate, inertial motion units, satellite positioning, and the physiological sensors that read pulse, respiration, and metabolic signals. This is where raw signal first leaves the body, and where comfort, placement, and power budgets shape everything that follows.

Wearables & Sensors technologies

Pulse from reflected light.

Optical Heart Rate Sensor

A wrist sensor that estimates pulse from light reflected off the skin, the technique known as photoplethysmography. It is comfortable and suited to all day wear, which is why it dominates consumer wearables, but high frequency motion genuinely corrupts the signal it reads. Accuracy is strong at rest and during steady effort and weaker during intervals and irregular movement.

Wrist or forearm wearable

Motion in three dimensions.

Inertial Motion Unit

An accelerometer, gyroscope, and magnetometer combined so that fusion yields orientation none of them could report alone. The gyroscope tracks smoothly but drifts, the accelerometer corrects drift against gravity, and the magnetometer anchors heading. Almost every cadence, stride, and repetition metric depends on this fusion working well underneath.

Body worn or embedded

Pace and route from orbit.

GNSS Positioning

Satellite positioning fused with motion data to reconstruct pace, distance, and route without a tethered phone. It is good enough to map a run through a city but too coarse and slow for tracking bodies packed onto a pitch. Accuracy degrades among tall buildings and dense cover, where the satellite signal is obstructed or reflected.

Outdoor wearable