3DM
®
-GX5-10
User Manual
12.
Glossary
A
A/D Value
The digital representation of analog voltages in an analog-to-digital (A/D) conversion. The accuracy of
the conversion is dependent on the resolution of the system electronics. Higher resolution produces a
more accurate conversion.
Acceleration
In physics,acceleration is the change in the rate of speed (velocity) of an object over time.
Accelerometer
A sensor used to detect and measure magnitute and direction of an acceleration force (g-force) in ref-
erence to its sensing frame. For example, at rest perpendicular to the Earth's surface an accelerometer
will measure 9.8 meters/second squared as a result of gravity. If the device is tilted the acceleration
force will change slightly, indicating tilt of the device. When the accelerometer is moving it will measure
the dynamic force (including gravity).
Adaptive Kalman Filter (AKF)
A type of Extended Kalman Filter (EKF) that contains an optimization algorithm that adapts to dynamic
conditions with a high dependency on adaptive technology. Adaptive technology refers to the ability of
a filter to selectively trust a given measurement more or less based on a trust threshold when com-
pared to another measurement that is used as a reference. Sensors that have estimation filters that
rely on adaptive control elements to improve their estimations are refered to as an AKF.
AHRS (Attitude and Heading Reference System)
A navigation device consisting of sensors on the three primary axes used to measure vehicle direction
and orientation in space. The sensor measurements are typically processed by an onboard algorthim,
such as an Estimation Filter, to produce a standardized output of attitude and heading.
Algorithm
In math and science, an algorithm is a step-by-step process used for calculations.
Altitude
the distance an object is above the sea level
Angular rate
The rate of speed of which an object is rotating. Also know as angular frequency, angular speed, or
radial frequency. It is typically measured in radians/second.
API (Applications Programming Interface)
A library and/or template for a computer program that specifies how components will work together to
form a user application: for example, how hardware will be accessed and what data structures and vari-
ables will be used.
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