Gyroscope
Gyroscope is available on Tag iMU only.
The role of the Gyroscope is to measure angular velocity around three orthogonal axes.
The Gyroscope provides the following functionalities:
- Orientation Determination*
- Send measured data*
*only one of these functionalities can be active per tag at one time
Rotation Determination
From the angular velocity, relative orientation of the tag around 3-dimension axes can be calculated. However, the sensor itself also has limitation when used on its own. Further description can be found in section Spatial Rotation Determination.
Available Data Formats
Three axis gyroscope data are received by any anchor in vicinity and provided to user via API.
There are two modes of operation.
- Send RAW data
- Send corrected data
Send RAW data
If this mode is active, the tag send RAW data measured by gyroscope.
Send corrected data
Tag subtracts the zero offsets from the RAW data before they are sent. These offsets are determined during inertial measurement unit calibration, which is described in Console Configuration and Calibration section Spatial rotation determination. In RTLS Manager, you can only enable or disable the streaming of gyroscope data, and RAW data are also available in this way. If you want to stream uncorrected data, you need to set it via console.
The user can set the dynamic range of the gyroscope. It is again possible via console or via wireless config message from RTLS Manager. Dynamic range can be set to ±250 dps, ±500 dps, ±1000 dps or ±2000 dps. The dynamic range should be set according to use case. If user sets low dynamic range, gyroscope can capture slow rotation, but fast rotation will be saturated. On the contrary if the high dynamic range is set, slow rotation will not be detected.
This functionality can be set in console or via wireless config message from the RTLS Manager.
Conversion formulas
Measured angular velocity is not sent in base units [rad s-1] but as dimensionless numbers. It is necessary to convert it by using following formulas. Used formula depends on dynamic range setting:
Dynamic range = ±250 dps
Dynamic range = ±500 dps
Dynamic range = ±1000 dps
Dynamic range = ±2000 dps