微小型无人直升机地面效应建模  

Ground effect modeling for small-scale unmanned helicopter

作　　者：陈迪仕[1] 张宇[1] 李平[1,2] 

机构地区：[1]浙江大学航空航天学院,浙江杭州310027 [2]浙江大学控制科学与工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2014年第1期154-160,共7页Journal of Zhejiang University：Engineering Science

基　　金：中央高校基本科研业务费专项资金资助项目(2012QNA4024);国家自然科学基金资助项目(61005085)

摘　　要：为了实现无人直升机近地面的平稳控制,建立较准确的近地面的直升机模型.通过实验和数据分析,研究微小型无人直升机地面效应对升力的影响.使直升机在不同载荷下保持悬停状态,测出在有地面效应(IGE)和没有地面效应(OGE)时的升力,进行定性分析比较,标定出旋翼提供的升力与总距的对应关系.保持直升机载荷不变,让直升机在不同的离地高度下,测出悬停时总距,参照第一步结果,可以算出不同高度下地效产生的升力及其占直升机自身重力的比重k,拟合出k关于高度的函数.在离地高度为某一定值的情况下,考虑此时的地效升力,搭建直升机非线性Simulink仿真模型.将实际悬停时的遥控器输入数据分别用于有地效和无地效的直升机仿真模型的输入,有地效的直升机模型输出的垂向速度和高度的变化更接近于实际试验数据,高度变化较小,证明了加入地效后的直升机模型在垂直方向上有很大的改进.A relatively accurate ground effect model of the helicopter was constructed in order to stably con- trol the small-scale unmanned helicopter when it flies close to the ground. The ground effect on lift force of small-scale unmanned helicopter was investigated through flight experiments and data analysis. When the helicopter hovered with different load, the value of lift force was respectively recorded while it was in ground effect （IGE） and out of ground effect （OGE）. The numerical relationship between the lift force provided by the rotor and collective was calibrated. The value of collective was recorded when the helicop- ter hovered at different height with the same load. The lift force provided by ground effect was calculated by referring to the former calibrated results, as well as its proportion k of the deadweight of the helicopter. Then a function combining k and height was fitted. A nonlinear simulation model of the helicopter was built, when the helicopter hovered at certain height affected by the ground effect. The sequence of control data from real hovering test was respectively inputted into IGE model and OGE model. The comparison of these two simulation results showed that output of IGE model performed closer to the actual flight data-- less variation in height, which improved the model of the helicopter in the vertical direction when involving in ground effect.

关 键 词：无人直升机 地面效应 悬停 

分 类 号：V249.122[航空宇航科学与技术—飞行器设计]