head-motion-ema

Ecological Momentary Assessment of Head Motion

Data collected from 10 subjects with Actigraph GT9X Link IMUs attached to waist and head.

• Sensors: accelerometer and gyroscope
• Sampling rate: 100 Hz
• Axes:
  • x: anterior/posterior (positive forward)
  • y: medial/lateral (positive left)
  • z: vertical (positive upward, perpendicular to Reid's plane for the head sensor)

Data is stored in the netCDF format with the following specification:

Dimensions:

axis:       ('x', 'y', 'z')
sample:     datetime64[ns]

Coordinates:

gender      string (M/F)
age         int64
weight      int64
height      int64
subject_id  string (001-010)

Data variables:

AccHead     (sample, axis) float64
GyrHead     (sample, axis) float64
AccWaist    (sample, axis) float64
GyrWaist    (sample, axis) float64

Accelerometer measurements of head (AccHead) and waist (AccWaist) are stored in g (1g = 9.81m/s). Gyroscope measurements of head (GyrHead) and waist (GyrWaist) are stored in rad/s. Excluded periods for either sensor location are stored as nan.

Files are stored in data/XXX.nc where XXX is the subject identifier (001-010). Demographic information is additionally available in data/subject_info.csv.