Method of calibration mems accelerometer and magnetometer for increasing the accuracy determination angular orientation of satellite antenna reflector

Abstract

The paper is devoted to the measurement errors investigation that arise due to the influence of MEMS accelerometers' nonlinear characteristics. They appear at large inclination angles of the antenna system support-rotary platform, as well as in the presence of a magnetic inclination, which is due to the peculiarity of the Earth's magnetic field for the magnetometer. The study was conducted to assess the possibility of using such devices to increase the accuracy of a satellite antenna control with a classic rotary platform. The experimental setup for researching the parameters of MEMS sensors allows comparison of measurement results with data obtained from precision optical encoder. The experimental results show the main sources of MEMS sensors errors. An accuracy increasing method of antenna system angular position determining using a triaxial accelerometer and a magnetometer is proposed. The main advantage of the proposed estimation vector determining approach using the least squares method is the possibility of carrying out the calibration procedure without reference to the coordinate system. The method makes it possible to get rid of the zero offset error, as well as compensate for the non-unit scale of the sensor axes and the error of the magnetometer angular orientation. This method can be used for many applications including robotics, design of unmanned aerial vehicles and many other technical systems. The proposed method makes it possible to increase the reliability and reduce the cost of such systems.