HID Sensor Usage Tables - USB.org

47 HID Sensor Usages
Separation or Ellipsoid Error.
GPS A device that receives (never sends) weak radio signals from a
series of satellites orbiting high above the Earth. Together these
form the Global Positioning System. Based on the content of the
signals sent by the satellites, a GPS receiver is able to compute its
location (Latitude, Longitude, and Altitude) on the Earth and
speed (in knots). At least four satellites must be “acquired” in
order for the GPS to “get a location fix”. This may take some
time, and is affected by how clear the view is to the satellites
(streets surrounded by tall buildings, or locations inside buildings
made of metal and concrete are problematic).
Gyro A device that measures Angular Velocity around one or more
linear axes (traditionally called X, Y, and Z). A Gyro is also
called a Gyroscope or a Gyrometer.
Gyrometer Another name for Gyro.
Gyroscope Another name for Gyro.
Hall Effect Sensor A binary switch that can detect the nearby presence of a magnet.
Classic use is as a laptop lid-closed detector.
Haptic Vibrator Motor An Actuator that rotates a motor with an off-balance weight on
the axle. This results in the types of vibrations that you may be
familiar with your cellular mobile phone producing. Typically
used when in “silent mode” to indicate the arrival of an email,
SMS message, and so on.
Heading Angle with respect to North. Magnetic Heading is expressed with
respect to the Earth’s Magnetic North Pole, while True Heading is
expressed with respect to the Earth’s Geographic North Pole.
Note that the Magnetic North Pole and the Geographic North Pole
are not at the same location on the globe. The North Magnetic
Pole moves slowly over time due to constant magnetic changes in
the Earth's core. In 2001, it was near Ellesmere Island in northern
Canada. The difference between the two poles is called Magnetic
Declination or Magnetic Variation. To calculate the True
Heading, you have to subtract the Magnetic Declination from the
reported Magnetic Heading. The correct value of Magnetic
Declination depends upon your position on the globe. Heading is
also called Azimuth, especially when referring to GPS satellite
positions in the sky.
(Human) Presence A sensor used to detect the presence (Boolean true or false) of a
human in front of the sensor. This is typically done using
reflection of infrared or ultrasonic waves.
(Human) Proximity A sensor used to detect the linear distance that a human is away
from (in front of) the sensor. This is typically done using
reflection of infrared or ultrasonic waves.
Humidity Sensor Another name for Hygrometer.
Hygrometer A sensor used to measure Relative Humidity, the percent
saturation of water in the atmosphere.
Inclinometer A sensor used to measure angular tilt with respect to one or more
axes (traditionally called X, Y, and Z).
Latitude A component of position on the Earth, measured as degrees of