基于改进互补滤波器的低成本微小飞行器姿态估计方法

摘要

针对微飞行器(MAV)在不同机动状态下如何获得对重力加速度的有效估计这一问题,提出一种具有增益调节机制的显性互补滤波器,对微飞行器类似周期性盘旋等典型状态,利用陀螺仪的测量和指示空速的估计构建了向心加速度补偿机制,使得基于重力加速度估计的互补滤波器能获得较为精确的姿态估计,并克服了传统互补滤波器对姿态估计进行重构的缺点.在比例积分补偿环节中,对俯仰角和横滚角的估计赋予不同的截止频率,使得比例增益和积分增益具有较好的自适应性.对比实验表明,姿态角估计误差能保持在±2°之内,与现有的典型滤波算法相比,该方法在算法效率和估计误差方面具有良好的综合性能,并适合用低成本的微惯性测量单元实现微飞行器的精确姿态估计.%Concerning the issue of how to achieve effective estimation of gravitational acceleration for attitude estimation of Micro Air Vehicle (MAV) under all dynamic conditions,an improved explicit complementary filter was proposed in combination with stepped-gain schedule.In order to validate the nonlinear complementary filter in the case when a MAV circled for an extended period,a centripetal acceleration mode was built using gyroscopes and indicated airspeed data,which resulted in precise estimation based on the estimation of gravitational acceleration and avoided reconstructing an estimation of the attitude.In the phase of Proportional-Integral (PI) compensation,the proportional gain and integral gain can achieve better adaptability by assigning different cut-off frequency value to the estimation of pitch and roll angles respectively.The experimental results show that the attitude angle estimation can be maintained under the range of ± 2°.Compared with the typical filter algorithm,a better performance was achieved with respect to the efficiency and estimation error,so the algorithm proposed in this paper can be applied to accurate attitude estimation for MAV with low-cost inertial measurement units.