Aiming at measurement problem of attitude angle of the four-rotor aircraft

using three axis accelerometer and gyro

propose an attitude signal fusion method based on Kalman filtering algorithm. In this method

the angular velocity error output by gyro is processed as time variable error

and this variable error is taken to be related with angular velocity error which gyro output in last measuring time as well as with the attitude angle which will be measured. According to this

gyro linear measurement equation is established. On this basis

the attitude angle output by gyro is modified by the attitude angle output by the accelerometer using of Kalman filtering algorithm

so as to achieve accurate measurement of attitude angle. The experimental results show that

after using Kalman filtering algorithm to fuse acceleration sensor and signal gyro

it can effectively eliminate the accumulative error and significantly improve dynamic characteristics of attitude angle measurement.