Aircraft convention defines the attitude parameters in terms of three angles: roll,
pitch and heading. These angles are referenced to the local horizontal plane defined by
gravity vector. Attitude information for aircraft is obtained by using spinning rotor or
ring laser gyroscopes. These systems are very precise but they suffer from many
problems such as high cost, large size and weight and the requirements for elaborate and
intricate mechanical structure.
These problems can be reduced by the exploitation of the micromachined technology.
In this work, an attitude measuring system based on the ADXL202
accelerometer, the HMC2003 magnetic sensor and the ADuC812 microcontroller has
been designed and implemented. An algorithm for decoding of the ADXL202 output
signals is described and implemented as software programs written in C-language to
perform and display the attitude measurements and a correction method for the errors
introduced by tilt angles is described.
The measuring system operation is examined by the test of the reading’s
repeatability and constancy. A good repeatability and constancy with a high degree of
precision and small amounts of error and dispersion are found from these tests.