变速变姿态下飞机燃油体积解算技术

Aircraft fuel volume calculation technique in state of variable velocity and attitude

为准确测量飞机不规则油箱内的燃油体积,在传统的查表插值法基础上,提出了基于等效传感器的自适应步长切割法(ASCM),用于建立燃油质量特性数据库,通过引入等效传感器概念,实现了不同姿态下多传感器的信息融合;该方法根据切片截面积的变化率调整切割步长,从而减小了燃油体积解算时的插值误差;利用多传感器的输出值实现了燃油平面的最小二乘(LMS)拟合,当有效传感器较少时,再结合等效燃油平面姿态角拟合燃油平面,消除了加速度对燃油平面的影响;对传统的三维查表插值法进行改进,减小了由于燃油平面姿态角插值引起的误差。基于UG二次开发,设计了燃油体积解算平台。实际油箱CAD仿真验证结果表明:该方法所建的数据库数据规模小,燃油解算速度快,实现了加速度和姿态误差修正,并减小了差值误差,进一步提高了燃油的测量精度。

To accurately measure remaining fuel in irregular tank, the adaptive step size cutting method （ASCM） which is used to build fuel quantity database is presented based on traditional look-up table and interpolation method. With the help of equivalent sensor, the method has integrated outputs of multi-sensor under different attitude. The method adjusts step size depending on the change rate of cross-sectional area to minimize interpolation error in fuel volume calculation. With multi-sensor＇ s outputs to fit fuel surface by least mean square（LMS） method. When valid output is less, equivalent surface attitude angles are taken to fit fuel surface. It eliminates influence on fuel surface caused by acceleration. Three-dimensional look-up table interpolation method is improved to minimize deviation caused by attitude angle. Fuel volume calculation software is programmed with UG development kits. A number of CAD simulations with actual tank model are done. The results suggest that the method has compressed database size, accelerated calculation speed, corrected deviation resulting from acceleration and attitude, and reduced interpolation error. Thus, fuel measurement accura- cy is improved.