Based on the analysis of UAV mission scenarios and operational requirements, this paper designs a pure electric multi-function, long endurance submarine launched UAV, and carries out a series of design, analysis and calculation. Determine the launch form, application scenario, size constraint, design index and aerodynamic layout of the UAV, and then design the wing, fuselage, power layout and tail fin of the UAV according to the overall design goal, and determine the preliminary design scheme of the UAV. Using CATIA software to draw the overall surface model; The calculation method is explained. The flow grid is drawn by CFD and the boundary conditions are set. Fluent was used for aerodynamic analysis, and a set of data of lift, drag and pitch moment coefficients were obtained according to different angles of attack. The static stability of the whole air-craft was analyzed, and the overall aerodynamic design and analysis of the submarine-launched UAV was completed. The re-sults showed that the aerodynamic characteristics of the UAV were good and the design index requirements were met. The pa-rameter table and electronic prototype of the whole machine are given.

微型无人机栖息设计研究对提升微型无人机续航、增强微型无人机环境适应性和提高微型无人机长时间侦察监视能力具有重要的意义.随着人们对微型无人机续航性能和复杂环境的适应性要求越来越高,科研工作者对微型无人机的栖息设计技术进行了深入研究,并取得了显著成果.主要梳理了微型无人机的栖息原理、栖息机构、栖息方法,分析了栖息机构的特点与发展趋势.同时介绍了变体无人机在栖息领域的研究,并阐述了无人机栖息与抓取和爬壁之间的联系.此外将无人机分为多旋翼和固定翼2大类来进行栖息方法的研究分析,内容主要包括无人机的栖息位置选择、基于时间接触理论的仿生轨迹设计、视觉栖息导航、无人机的气动分析和动力学建模以及相应的栖落机动控制等.通过对无人机栖息设计技术的研究归纳分析,可为后续从事该方面的研究人员提供参考和借鉴.

Based on the wind field characteristics of high-rise buildings, this paper studies the wind resistance stability of multi-rotor UAV flight platform, conducts research on the design technology of high-wind resistance flight platform, improves the safety and reliability of fire fighting and extinguishing UAV, and provides technical support for the design and optimization of fire fighting and extinguishing UAV. Based on various aerodynamic data under no-load and on-load conditions, the wind resistance of the UAV is analyzed, and a set of wind resistance evaluation methods for the multi-rotor fire fighting and extinguishing UAV is proposed. The wind static model of the multi-rotor fire fighting UAV is established to evaluate the wind resistance of the UAV. The results show that: the designed fire-fighting UAV can theoretically resist the wind of level 7 (16 m/s), and the UAV can achieve the balance of force and torque by adjusting its attitude under the horizontal action of level 7 wind.

High-rise building fire extinguishing UAV is a new equipment used in high-rise building fire extinguishing and rescue. However, the turbulent environmental airflow in the high-rise building area and the complex wind field pose a threat to the stability of fire fighting and fire fighting drones, which puts forward higher requirements for the stability and wind resistance of multi-rotor UAV flight platforms. Therefore, aiming at multi-rotor drones that perform fire fighting tasks in high-rise buildings, the characteristics of wind fields between buildings in high-rise buildings are studied to provide technical references for the design and optimization of fire-fighting drones, which not only has important theoretical significance, but also has high practical value. With multi-rotor firefighting drones as the background, based on the computational fluid dynamics (CFD) theory and Fluent software, the wind field characteristics around high-rise buildings are studied, carrying out numerical simulation analysis of the wind field around single buildings and multiple buildings to provide a reference for the actual flight of fire extinguishing drones between buildings. The analysis results show that: Compared to the single building, the wind field around the building has changed a lot when the two buildings are arranged, and the aerodynamic interference between the two buildings is significantly weakened as the distance between the buildings increases; Layout and the surrounding buildings play a shielding role. The wind and shadow areas are superimposed on each other, and the air flow is complicated. Drones should avoid flying in these complex wind fields as for as possible.

This paper proposes a new type of pure electric vertical take-off and landing fixed wing general long endurance UAV, and carries out a series of design, calculation and analysis on it. Firstly, use CATIA to perform three-dimensional modeling of the UAV, determine the aerodynamic shape of the UAV, and analyze the calculation method. Secondly, use CFD to divide the mesh, set the boundary conditions, and verify the independence of the mesh. Finally, Fluent is used to calculate the aerodynamic characteristics, the lift-drag characteristic curve, the pitching torque curve, the corresponding pressure cloud graph and the aerodynamic characteristics of the whole UAV under different lateral wind speeds at different attack angles are obtained. The calculation results show that the aerodynamic characteristics of the UAV are good and meet the design index requirements.

This paper designs a large-load multi-rotor fire-fighting UAV. Use CATIA three-dimensional drawing software for auxiliary design to control the size and weight of the drone within a reasonable range. After obtaining the three-dimensional model of the fire-fighting drone, HyperWorks finite element analysis software was used to perform finite element analysis on the airframe structure composed of carbon fiber composite materials and aluminum alloy. The results showed that the strength and rigidity of the airframe structure meet the design and use requirements.

In this paper, two basic aspects of multi-rotor UAV, the air braking capability and obstacle avoidance function, are analyzed and studied on a certain type of fire-fighting UAV. Firstly, based on the motion model, the force analysis of the UAV is carried out to explore the factors that affect the braking ability; the mathematical relationship is established between the influencing factors and the braking distance, and the braking problem is solved in PYTHON. After that, the obstacle avoidance function of the multi-rotor UAV is developed based on the ROS environment. Several commonly used obstacle detection technologies and path planning algorithms are introduced and their advantages and disadvantages are compared. Under the ROS environment, simulating the advanced obstacle avoidance strategy according to VFH algorithm, and using PX4 external control mode in Gazebo simulation environment to verify the feasibility of the designed obstacle avoidance strategy. The results show that in actual flight, when the braking pitch angle is 30°, the UAV can slow down and hover within a safe distance of 10 m, meanwhile the advanced strategy based on VFH algorithm can be realized in simulation environment.

In recent years, the application demand of UAV has been increasing rapidly. In the face of complex tasks, the mission capability of a single UAV is limited. Comparatively, multi UAV formation can greatly improve the efficiency, reliability and redundancy. This paper presents a multi UAV formation method based on ROS system. Firstly, several UAV formation methods are introduced. With the comparison of these methods, the distributed formation method is adopted. Then, the software architecture of UAV formation system is designed based on ROS system. And on this basis, the estimation node, control node, formation node and display node are designed. By subscribing to Px4 flight control node, the estimation node obtains the UAV status, position, speed and Euler angle. Then the estimation node converts the message format and publishes them for other nodes to use. The control node subscribes to the formation control command of the formation node, estimates the UAV state information of the node, calculates the expected speed of the UAV through the previously adopted formation control algorithm, and sends the message to the Px4 control module. In addition, the control node establishes contact with the control module to realize the functions of unlocking, locking, takeoff and landing. The formation node can calculate the relative deviation of UAV formation position according to different formation requirements. The display node is used to display the current status of UAV, including position, speed, yaw angle, etc. Finally, the feasibility of the formation control method is verified in the Gazebo simulation environment, and the results show that the method can realize formation flying, formation transformation and maintenance. The above contents lay a certain foundation for the future related research and can be used for reference.

In this paper, two methods, basic reliability analysis and mission reliability analysis, are used to analyze and calculate the system reliability of "Sky Dragon I" eight-rotor fire-fighting UAV specially designed for high-rise building fires and developed by the research group. The two methods are based on the reliability model, considering the correlation among the units of the reliability model, the upper and lower bounds of the system reliability, system failure rate and MTTF of the series and parallel reliability model are deduced, and the reliability parameters of "Sky Dragon I" are calculated. The novel points of this paper are as follows: 1) The application of the two methods in the complex system of eight-rotor fire-fighting UAVS is a brand-new research. 2) Most of the traditional system reliability research is based on the premise that each unit is independent of each other. In this paper, a new analysis and calculation is carried out under the premise of considering the correlation among the units of the reliability model. The results show that the reliability of the UAV meets the requirements. However, the safety and reliability of the whole system are not perfect enough. In order to improve the safety and reliability of the fire-fighting UAV, the corresponding reliability design optimization and tests will be carried out later.

One of the biggest technical challenges of supersonic flight is the mitigation of sonic boom. To deal with this problem, the Gulfstream Aerospace Corporation came up with the spike concept, and it showed to be efficient. However, there also remain several problems, the first one is that installing the spike makes it harder to balance for supersonic transport and the another one is that the movement equipment is complex. In this paper, a new concept by replacing the multi-stage of the normal spike with smooth transistion cones is proposed. The concept simultaneously uses the CFD solver HUNS3D based on the Reynolds average (RANS) equation and the far-field FL-BOOM sound explosion propagation program based on Thomas waveform parameter method. The effectiveness of the present scheme to suppress supersonic aircraft sound explosion is verified according to the concept. It is proved that the increased length is good for low blast and the main factor affecting the blast reduction effect of multistage mute cone is length rather than series by the analysis. The results have important reference value for the silent cone design of supersonic aircraft.

After the conceptual design of a six-rotor UAV, a detailed 3D model was built in CATIA, in which complete details of the structure was designed. Then static and dynamic structural analysis was carried out by using ANSYS. By applying the loads and the other forces which will effect on the structure, analysis was done on the complete UAV. Also, the structure analysis is carried out on the landing gear by applying all the forces which are acting on it. Through the analysis of the stress on the six-rotor UAV under different working conditions, the results show that the UAV is strong enough under the loading condition of 5 kg.

A hybrid aerial vehicle (HAV), featured combination of a quadrotor system and a fixed-wing system, is one of the most promising configurations having both a vertical take-off and landing (VTOL) capability and high cruise performance. In this paper, a HAV has been designed and prototyped to analyze the performance of the HAV. The specifications of the HAV are summarized. The aerodynamic coefficients of the HAV derived from CFD data and the influence of axial flow on the maximum thrust of quad propellers that is calculated using QPROP are demonstrated, respectively. The wind resistant capability of the HAV is analyzed from two aspects according to different wind direction. The factors which have important influence on the wind resistant capability of the HAV are analyzed and the solutions to improve the wind resistant capability of the HAV are presented.

A preliminary study of optimizing the skin lamination on the straight section of the fuselage has be done when only the airtight loads is considered. Combined the finite element software NASTRAN solver and the genetic algorithm to achieve the specific process by ISIGHT software,and to make up for deficiencies by ISIGHT C + + programming. Under airtight loading,analysis obtained the best lamination sequence,ply angles and layers of the fuselage skin. Contrast the before and after the optimization of composite fuselage,the equivalent section of the fuselage to reduce the 16. 2% of the body weight of the structure; contrast to the metal air-frame of A320-200,corresponding fuselage sections reduced 26. 5%,improving the structural efficiency.The calculation method can be automated to improve the computational efficiency. This method can achieve the initial read,automated calculations and read the results of the whole process,and reduces the amount of computation time.

The oleo-pneumatic damper with two air chambers will have optimal performance by the rational design of structure parameter.The landing gear prototyping model should be established based on an existing landing gear, dynamic analysis of the impacting with the run way procedure were simulated with the established model using ADAMS/Aircraft, some data points could be obtained.The function relationship between parameters and optimization ob-ject could be built with sample point based on the weighting nonlinear response surface meth-od.Setting the efficiency of buffer as optimization object, the max vertical load and stroke as constraint condition, the parameters can be optimized.The conclusion suggested that there are 1.2%difference between the optimization results and the simulation results, and the effi-ciency of buffer has 4.6% increases.This paper developed a method of buffer design and improving.

Sonic boom reduction will be an issue of utmost importance in future supersonic transport, due to strong regulations on acoustic nuisance. The paper describes a new multi-objective optimization method for supersonic aircraft design. The method is developed by coupling Seebass–George–Darden (SGD) inverse design method and multi-objective genetic algorithm. Based on the method, different codes are developed. Using a computational architecture, a conceptual supersonic aircraft design environment (CSADE) is constructed. The architecture of CSADE includes inner optimization level and out optimization level. The low boom configuration is generated in inner optimization level by matching the target equivalent area distribution and actual equivalent area distribution. And low boom/low drag configuration is generated in outer optimization level by using NSGA-II multi-objective genetic algorithm to optimize the control parameters of SGD method and aircraft shape. Two objective functions, low sonic boom and low wave drag, are considered in CSADE. Physically reasonable Pareto solutions are obtained from the present optimization. Some supersonic aircraft configurations are selected from Pareto front and the optimization results indicate that the swept forward wing configuration has benefits in both sonic boom reduction and wave drag reduction. The results are validated by using computational fluid dynamics (CFD) analysis.

以布兹曼双层翼为基础，采用基于压力梯度自适应的非结构网格求解欧拉方程的计算流体力学(CFD)方法，计算分析了双层翼翼型的厚度和翼面间距对阻力特性的影响。在马赫数为1.7的情况下，由于激波的反射和干涉，超声速双层翼翼型的阻力系数仅为0.00189，为相同厚度菱形翼型的1/15。本文通过进一步的研究发现：减少翼型厚度对于双层翼翼型设计马赫数的阻力系数有一定的影响，且与超声速状态相比，厚度对于亚声速状态的阻力影响更大，厚度减少20%，亚声速状态的阻力系数减少可达60%以上；翼面间距对阻力特性的影响相对复杂，设计马赫数之前的阻力系数与翼面间距成反比，而设计马赫数之后的阻力系数与翼面间距成正比。在此基础上，基于激波的反射及干涉效应，提出了一种双设计状态的双层翼翼型，在最佳设计点之前，双层翼之间的激波/膨胀波会有两次反射，使翼型前后的压力基本相同，阻力系数出现一次下降。随着马赫数的增加马赫角减少，激波经过一次反射就能使翼型前后的压力基本相同，使翼型达到最佳设计状态。计算结果表明，双设计状态双层翼能够使双层翼翼型在两个设计点都具有较低的阻力系数。

在飞机起落架优化设计的研究中,双气腔油气式缓冲器具有功量吸收能力大,缓冲效率高的特点,但性能易受初始充填情况的影响,如何对双气腔油气式缓冲器进行仿真分析成为研究重点。首先建立起落架的数字模型,通过ADAMS软件中的Aircraft计算分析模块结合特性文件对起落架着陆撞击的动力学特性进行仿真。通过对比正常充填条件下的仿真结果与试验结果,发现误差在4.3%以内,仿真方法有效可信。依据缓冲器高低压气腔不同的充填情况,分别进行仿真,对比不同充填情形下的仿真结果,得出该型起落架缓冲器的充填容差特性。建立了一种研究双气腔油气式缓冲器双腔充填对缓冲性能影响的分析方法。仿真结果有一定的工程应用和参考价值。

探索了基于混合网格的近场预测以及基于波形参数法的远场预测相结合的声爆预测方法,综合利用了结构化网格计算效率高以及非结构网格对复杂外形适应性好的优点,在保证声爆预测精度的基础上提高了计算效率.在此基础上,建立了基于声爆预测方法、响应面模型和Pareto遗传算法的声爆/气动一体化设计方法.分析表明,发动机短舱对超声速升阻特性和声爆特征都有较大影响,利用声爆/气动一体化设计方法对发动机短舱位置进行了一体化设计研究.结果表明,建立的响应面模型的精度完全满足要求,根据不同的设计偏向选择了三种优化方案,优化后方案的性能较原始方案都有不同程度的提高.

类别形状修正函数变换(CSRT)方法是在类别形状函数变换(CST)方法的基础上添加修正函数以克服其不具备局部性的缺点发展而来的新型参数化方法.通过考察参数化过程中翼型的表示误差和线性系统条件数,对CSRT和CST参数化方法的表示精度和数值单值性进行了对比.使用基于以上两种参数化方法的远场组元(FCE)激波阻力优化算法对超声速翼身组合体进行了零升激波阻力优化,结果对比得到:基于CSRT方法的两级优化具有更好的优化效果,激波阻力系数降低了34.7％.研究表明:CSRT方法需要比CST方法更多的参数数量以达到相似的精度,随参数数量的增长,CSRT参数化过程的病态化程度远低于CST方法;CSRT参数化方法可以结合适当的优化算法进行气动外形二级优化,其效果优于使用相同参数数量的CST参数化方法所进行的单级整体优化.

Sonic boom suppression method is the key technology of next generation supersonic aircraft. Low boom mechanism of the off-body energy deposition is analyzed by using the thermal chocking model. The mass flux of energy deposition region is small than no energy deposition region, and off-body energy deposition will induce a bow shock wave. The mechanism of off body energy deposition is similar with quiet spike, so it can be regard as a virtual quiet spike. Off-body energy deposition analysis software is developed based on CFD, waveform parameter method and NSGA-II genetic algorithm. The location coordinate, value, shape and location number of energy deposition are the key parameters in low boom design. Initial pressure of optimized energy deposition decrease near about 54.65 than no energy deposition, and rise time increase 543.2%.