Aiming at the unmanned aerial vehicle strapdown attitude and heading reference system（ AHRS）which is made of a three-axis magnetic sensor

a three-axis micro-electro-machanical system（ MEMS）accelerometer and a three-axis MEMS rate gyroscope

based on a detailed analysis of the errors sources of the three types of sensors

error mathematical models according to the error sources of the sensors are established. Relying on own characteristics of sensor and measurement characteristics of nine-axis sensor

corresponding error compensation algorithm are proposed. Experimental results show that the maximum error of heading angle of the fluxgate sensor is reduced from 15° to 1. 6° after compensation. The maximum error of pitch angle is 0. 25° and the maximum error of tilt angle is 0. 35°. For static error compensation of rate gyroscope within 3. 5 minutes

the heading angle error is ± 0. 3°

the pitch angle error is ± 0. 4° after compensation

the tilt angle error is ± 0. 4° after compensation. When the speed is less than 15°/s

dynamic error is controlled within ± 1°.