Design And Implementation Of The Horizon Sensor Based On MEMS Gyroscope

Because of its unique function,the horizon has always been regarded as the primary flight instrument,known as "the king of instruments".Any aircraft or spacecraft has to be equipped with the instrument device and plays an important role in aerospace and other fields.With the development of aviation instruments,the traditional horizon is composed of a mechanical gyroscope.Due to its large size and poor reliability,it is difficult to meet its performance requirements of small size,low cost and high precision.Inertial navigation technology with its own advantages in any harsh environment,without external auxiliary equipment can achieve a variety of carrier navigation information measurement(attitude,speed and location,etc.),in which the MEMS(micro-electro-mechanical system)devices are widely used in attitude measurement systems because of their high reliability.Aiming at the shortcomings of the traditional system,this paper designs a set of horizon system based on MEMS gyroscope.This system can accurately measure the attitude information of vehicles without any external information,and has the advantages of small size,low cost and reliability In addition to being applied to the aerospace field,the advanced features can also be applied to the fields of stable platforms,marine equipment,automotive smart electronics and the like.The main work of this paper is as follows:(1)Design of attitude calculation algorithm and simulation analysis.Based on traditional Mahony Complementary filter algorithm,designed the improved adaptive Mahony Complementary filter algorithm.At the same time,the extended Kalman filter algorithm model of the system is established.Through simulation experiments,the design of the improved adaptive Mahony Complementary filter algorithm is more adaptive to flight conditions than extended Kalman filter algorithm.(2)The overall design and implementation of the horizon system based on MEMS gyroscope.First according to the requirements of the system,the main components of the system were selected.and then the hardware platform of the system is built and the software system is designed.The hardware platform of the system is mainly divided into three parts: inertial navigation system board and inertial measurement unit installation board and power module.inertial navigation system board collect the data of sensor and calculate the attitude,then the attitude information sent out through the serial port RS-232;inertial measurement unit mounting plate is to achieve the system level design,the inertial measurement unit is fixedly connected to the bottom of the shell,with the transfer board to achieve inertial measurement unit and inertial navigation system board communication;power module to achieve the power of each module of the system.The software system design includes system initialization,IMU data acquisition and calibration,attitude calculation and data transmission.(3).System test verification.In order to verify the actual performance of the system,conducted a series of tests such as electrical interface test,high and low temperature test,static turntable test,racing car test and flight test.The test results are as follows: the attitude precision of the static state is 0.2 degrees;and the attitude precision under the dynamic state is within 3 degrees.The experimental data show that the horizon system to meet the aircraft attitude measurement performance requirements,and low cost,small size,does not rely on external information,reliable performance.