The thesis describes development of an attitude and heading reference system (AHRS). The thesis includes the description of used hardware of a magneto-inertial measurement unit (IMU) and description of a Kalman filter. The Kalman filter algorithm was used to upgrade IMU into AHRS. Integrated 3D gyroscope, 3D accelerometer and 3D magnetometer make IMU a 9 degree of freedom measurement device.
Development of IMUs, that is driven by progress of integrated circuits and the necessity for simple measurements of orientation is described in introduction. There are also a few areas of IMU usage listed and some products already available on the market, that use IMU, for tracking motion.
The second chapter gives the description of three versions of Kalman filter. From the very first version of the discrete Kalman filter to the Extended Kalman filter, and finally the Unscented Kalman filter, that was used for AHRS.
Detailed description of hardware is given in the third chapter. Measuring principles of IMU sensors and their properties are listed there. Communication module is IEEE 802.15 and ZigBee compliant, so description of both standards is given. The comparison of the ZigBee and Bluetooth technologies is provided.
In the fourth chapter software for AHRS is described. Description of it's user interface, Kalman filter implementation and communication is given there.
Measurements of normal and fast motion are analysed in the last chapter. For each measurement there is a graph of sensors output, graph of calculated and measured quaternion and difference between them, transformed into error angle.
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