Small wearable sensors can provide movement information
during daily-living tasks, performed within realworld
environments, instead of the simulated activities
used in most clinical assessments. Gyroscopes and accelerometers
are inertial sensors that are inexpensive, small,
portable, and can be applied in common point-of-care
environments or in the community (i.e., outdoors, stairs,
ramps, etc.). Inertial sensors directly measure angular
velocity and linear acceleration of body segments, from
which other body motion parameters can be calculated.
Inertial sensors in physical activity-monitoring systems
have been used to detect falls, and several review papers
summarize advances in this area