变距变转速多轴旋翼飞行器性能分析与试验

分析了制约现有多旋翼无人机性能方面的影响因素，提出通过旋翼变距变转速来改善其飞行性能的方法；综合动态失速、桨叶非定常挥舞与旋翼动态入流模型，建立了旋翼变距与变转速的气动模型，为准确的性能分析奠定基础；研制了变距变转速多旋翼试验样机并进行了飞行试验。试飞试验结果与理论计算结果表明:飞行器随着起飞质量的增加，需用功率明显增加；飞行器在不同起飞质量，不同旋翼转速下的需用功率值理论结果与试飞试验结果对比表明,小起飞质量下的功率计算值与实验值相符程度达到97%,而在大负载下理论计算值与实验值相符程度也在95%左右,证明了理论分析方法能较好的预估飞行器的气动特性和性能指标。进一步的理论计算表明,旋翼变距和变转速技术能够有效提高多旋翼飞行器起飞质量，续航时间等关键性能指标。 

Performance analysis and test of multi-rotor aircraft withvariable rotor collective pitch and rotation speed

The critical influential factors limiting the flight performance of conventional multi-axis aircraft were analyzed. The method to improve the flight performance of multi-rotor aircraft was studied by means of variation of rotor collective pitch and rotational speed. Based on dynamic stall, unsteady flap and dynamic inflow model, a comprehensive aerodynamic theoretical model was developed to analyze the flight performance. A demonstrator multi-axis rotor aircraft was developed for flight test. The flight experimental results and theoretical results showed that the aircraft required power increases obviously with the increase of takeoff weight. Under different payloads and rotor rotational speed conditions, experimental and theoretical required very good agreement of the power results up to 97% at light load reach and 95% at heavy load respectively. By means of comparison and analysis, the theoretical performance analysis method was validated. And furthermore the simulation demonstrated that variation of the rotor collective pitch and rotational speed evidently improved maximal take-off weight and flight duration of multi-axis aircraft.