Introduction - If you have any usage issues, please Google them yourself
The attitude information is one of the most important
parameters in flight control systems. This paper describes an
attitude measurement system based on a MEMS multi-sensor. The
data from 3-axis MEMS accelerators and 3-axis MEMS gyros is used
to determine the pitch angle and the roll angle of the air vehicle using
an extended Kalman filter (EKF) equation deduced from the
direction cosine matrix. An expert system was designed to estimate
the vehicle motion to adjust the measurement noise matrix of the
extended Kalman filter equation so that the system can be used in
dynamic as well as static environments. The measured airspeed and
altitude are also used to revise the pitch angle. The heading is
determined from GPS information. Test results compare well with
an imported commercial autopilot in a static test with less accurate
results in a dynamic test.