Design methodology of a mini-missile considering flight performance and guidance precision

The design of mini-missiles(MMs)presents several novel challenges.The stringent mission requirement to reach a target with a certain precision imposes a high guidance precision.The miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight performance.Pursuing a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC system.Herein,a multi-objective and multidisciplinary design optimization(MDO)is proposed.Disciplines pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO framework.The optimization problem seeks to maximize the range and minimize the guidance error.The problem is solved by using the nondominated sorting genetic algorithm II.An optimum design that balances a longer range with a smaller guidance error is obtained.Finally,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach.

ENERGY STATE APPROACH TO THE INTEGRATED FLIGHT PERFORMANCE MANAGEMENT OF COMMERCIAL AIRCRAFT

The integrated aircraft flight performance management techniques are discussed in this paper based on the point-mass energy state approximation principle. The flight performance optimization algorithms, developed with energy state approximation approach, are first introduced, the functionally integrated flight path/speed control system, so called total energy control system (TECS), is then discussed, and the guidance technique and algorithms, which relate the performance optimization results directly with the TECS, are analyzed and developed. Digital simulation results for a specific transport aircraft model demonstrate the satisfactory performances of the resulted flight performance management system.

Human factors quantification via boundary identification of flight performance margin

A systematic methodology including a computational pilot model and a pattern recognition method is presented to identify the boundary of the flight performance margin for quantifying the human factors. The pilot model is proposed to correlate a set of quantitative human factors which represent the attributes and characteristics of a group of pilots. Three information processing components which are influenced by human factors are modeled： information perception, decision making, and action execution. By treating the human factors as stochastic variables that follow appropriate probability density functions, the effects of human factors on flight performance can be investigated through Monte Carlo（MC） simulation. Kernel density estimation algorithm is selected to find and rank the influential human factors. Subsequently, human factors are quantified through identifying the boundary of the flight performance margin by the k-nearest neighbor（k-NN） classifier. Simulation-based analysis shows that flight performance can be dramatically improved with the quantitative human factors.

Interspecific comparison of the flight performance between sparrowhawks and common buzzards migrating at the Falsterbo peninsula： A radar study

In order to compare the two species＇ flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparrowhawks Accipiter ni- sus and common buzzards Buteo buteo during autumn migration. The results showed a clear difference between sparrowhawks and common buzzards in their flight altitudes and speeds, and in the wind conditions they encountered. Common buzzards had higher flight altitudes and were more selective of wind. Flight altitude was negatively related to the wind speed, which was most pronounced for common buzzards. Sparrowhawks had higher mean air- and cross-country speeds than common buzzards. Air- speed was negatively related, whereas ground and cross-country speeds were positively related to the tailwind component for both raptors. The differences between sparrowhawks and buzzards could to a large degree be explained by a larger dependence on thermal soaring among the common buzzards; a strategy associated with selectivity for favourable thermal and wind conditions during migratory flight. An additional important explanation for the interspecific differences was the habit of the sparrowhawks to combine migratory flight with hunting for prey, which makes it prone to fly at lower altitudes and use flapping flight to a much larger degree than common buzzards which do not forage during their migratory passage of the Falsterbo Peninsula [Current Zoo- logy 60（5）： 670-679, 2014].

Study on the lift and propulsive force shares to improve the flight performance of a compound helicopter

To investigate the effects of lift and propulsive force shares on flight performance,a compound helicopter model is derived.The model consists of a helicopter model,a wing model and a propeller model.At a low speed of 100 km/h,the Lift-to-Drag ratio(L/D)of the compound helicopter is improved when the wing provides 20.2%of the take-off weight.At high speeds,the L/D can be improved when the propeller provides the total propulsive force.Lowering the main rotor speed increases the wing lift share,however,the maximum L/D increases first and then decreases.The maximum L/D increases with decreasing the blade twist of the main rotor.Decreasing the blade twist from-16°to-8°increases the maximum L/D by 2.3%,and the wing lift share is increased from 65.0%to 74.7%.When the main rotor torque is balanced by the rudder,the maximum L/D is increased by 2.2%without changing the wing lift share.The wing should provide more lift as increasing the take-off weight,which reduces the induced power of the main rotor and increases the L/D.When increasing the take-off weight from 9500 kg to 11000 kg,the maximum L/D is increased by 6.5%,and the wing lift share is increased from 74.7%to 80.2%.

Reliable flight performance assessment of multirotor based on interacting multiple model particle filter and health degree

Multirotor has been applied to many military and civilian mission scenarios. From the perspective of reliability, it is difficult to ensure that multirotors do not generate hardware and software failures or performance anomalies during the flight process. These failures and anomalies may result in mission interruptions, crashes, and even threats to the lives and property of human beings.Thus, the study of flight reliability problems of multirotors is conductive to the development of the drone industry and has theoretical significance and engineering value. This paper proposes a reliable flight performance assessment method of multirotors based on an Interacting Multiple Model Particle Filter(IMMPF) algorithm and health degree as the performance indicator. First, the multirotor is modeled by the Stochastic Hybrid System(SHS) model, and the problem of reliable flight performance assessment is formulated. In order to solve the problem, the IMMPF algorithm is presented to estimate the real-time probability distribution of hybrid state of the established SHS-based multirotor model, since it can decrease estimation errors compared with the standard interacting multiple model algorithm based on extended Kalman filter. Then, the reliable flight performance is assessed with health degree based on the estimation result. Finally, a case study of a multirotor suffering from sensor anomalies is presented to validate the effectiveness of the proposed method.

Lysophosphatidylcholine Biomarkers of Lung Cancer Detected by Ultra-performance Liquid Chromatography Coupled with Quadrupole Time-of-flight Mass Spectrometry

Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients and 34 healthy volunteers were prepared with this approach. With ultra-performance liquid chromatography（UPLC） coupled with quadrupole time-of-flight mass spectrometry（Q-TOF MS） analysis, the samples were investigated in order to find potential disease biomarkers. After data acquisition, orthogonal signal correction partial least squares models were built to differentiate the healthy volunteers from lung cancer patients and to identify metabolites that showed significantly different expression between the two groups. Several metabolite ions were identified as potential biomarkers according to the variable importance in the project（VIP） value in both ion modes. Five lysophosphatidylcholines were further identified as specifically lysoPC 16：0, isomer of lysoPC 16：0, lysoPC 18：0, lysoPC 18：1 and lysoPC 18：2. These results suggest that UPLC coupled with Q-TOF MS is an effective technique for the analysis of plasma metabolites in metabonomic studies.

基于Matlab/Flightgear飞机飞行性能的可视化仿真系统

通过建立非线性六自由度飞行动力学模型和飞行仿真模型,借助Matlab可视化编程工具,利用Flightgear（飞行模拟器）的输入/输出接口将仿真数据实时传输。驱动Flightgear模拟器实现了飞行仿真的可视化,真实的模拟了飞机的降落过程,并得到飞机飞行性能参数随时间变化的曲线。

Screening for Plant Toxins in Honey and Herbal Beverage by Ultrahigh-Performance Liquid Chromatography-Ion Mobility-Quadrupole Time of Flight Mass Spectrometry

The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time of flight mass spectrometry (IM-QTOF MS) in positive ion mode. A database of 308 plant toxins including retention time, collision cross-section (CCS) and its fragment ions was established. Honey dissolved in water or herbal beverage was extracted by acetonitrile and purified with PSA sorbent, and then acquired by ultrahigh-performance liquid chromatography IM-QTOFMS. The acquired data were processed by comparing with the database we established to confirm the target compounds. The average recoveries for samples at two levels ranged from 60.6% - 120.1%, with relative standard deviation (n = 6) less than 25%. The limit of quantitation for plant toxins ranged from 1 - 20 μg/kg. The developed screening method was used in determination of honey, herbal beverage and honey flavored tea beverage samples. The results showed that berberine was detected in one honey with 1 μg/kg and caffeine was present in some beverages with the concentration from 200 and 5500 μg/kg. This method could meet the requirement for rapid screening of plant toxins in honey and herbal beverage. It can be used for the quality control of honey and herbal beverage in enterprises or quality inspection departments. It also can be used in the rapid screening of food poisoning.

Performance analysis and design of loitering munitions: A comprehensive technical survey of recent developments

Loitering munitions are increasingly used in armed conflicts.An extensive database of loitering munitions is developed based on information available in the public domain.This database includes dimensions,weights,and performance parameters such as flight endurance and communication range.Based upon this dataset,6 categories of loitering munitions are identified and statistical trends in the form of equations are provided for each category.The statistical trends are supported by aircraft performance theory tailored to loitering munitions applications.Altogether,the combination of the database,statistical trends and aircraft performance theory can be used to analyse the flight performance and design considerations of new loitering munitions of which only limited non-technical information is available in the public domain such as pictures and news articles.Based on the statistical trends and aircraft performance theory it is concluded that for long range applications,the preferred design solution is the conventional configuration.The cruciform configuration is beneficial in case precision flight path control is of prime importance.The tandem wing configuration combines the benefits of a canister launch and relatively high aspect ratio wings suitable for long range flight.Finally,the delta wing design provides a large internal volume and a high terminal attack airspeed.Two example case studies are included to illustrate the flight performance capabilities of two types of loitering munitions used in the current conflict in Yemen(a long range conventional design and a delta wing configuration).

Performance Analysis of Slowed Rotor Compound Helicopter

The performance of slowed-rotor compound aircraft,particularly at high-speed flight condition,is examined.The forward flight performance calculation model of the composite helicopter is established,and the appropriate wing and propeller parameters are determined.The predicted performance of isolated propeller,wing and rotor combination is examined.Three kinds of tip speed and a range of load share setting are investigated.Propeller bearing 80%of the thrust with wing sharing lift is found to be the best condition to have better performance and the maximum L/D for maximum forward speed.Detailed rotor,propeller,and wing performance are examined for sea level,1000 m,and 2000 m cruise altitude.Rotor,propeller,and wing power are found to be largely from profile drag,except at low speed where the wing is near stall.Increased elevation offloads lift from the rotor to the wing,dropping the total power required and increasing the maximum speed limit over 400 km/h.

SA METHOD FOR PREDICTING THE PERFORMANCE OF DASH STOP MANEUVER OF HELICOPTER

The Dash Stop flight at the extreme condition is the primary interest of this study. This paper describes some research on the flight characteristics of helicopter in Dash Stop. A set of equations which govern the Dash Stop is developed. A method which determines the acceleration and deceleration is proposed. Formulas are then developed which relate the aircraft angular rates and attitudes to flight speed, angle of attack and acceleration or deceleration. Finally the DOLPHIN helicopter is taken as an example to calculate its acceleration/deceleration capability, pilot control and aircraft attitudes in space. It is found that the results are reasonable.

Optimal speed of hypersonic cruise flight

A coupling frame of speed gain and maintain was suggested to assess the flight performance of hypersonic cruise vehicles(HCV).The optimal cruise speed was obtained by analyzing the flight performance measured by the ratio of initial boost mass to generalized payload.The performance of HCVs based on rockets and air-breathing ramjets was studied and compared to that of a minimum-energy ballistic trajectory under a certain flight distance.It is concluded that rocket-based HCVs flying at the optimal speed are a very competitive choice at the current stage.

Performance of two different modules of long-strip multi-gap resistive plate chamber

Long-strip multi-gap resistive plate chamber(LMRPC) were built with(Module 1) or without(Module 2) adhesive tapes and silicones.Their performances were investigated by working gas mixtures of different gradient contents(Test 1:94%freon,5%iso-butane and 1%SF_6;Test 2:90%freon,5%iso-butane and 5%SF_6).Both the modules achieved 100%efficiency,with time resolutions of 75 and 70 ps.Comparatively,the Module 1 works with a lower applied HV at the higher noise level,and time resolution was not influenced greatly by the adhesive tapes and silicones.

动压相似对缩比飞行的影响

模型飞行试验作为空气动力学研究的重要手段之一,正逐步成为新型飞机研发中一种有效和低风险的技术途径。目前低速飞行试验技术已经相对成熟,而高速飞行试验尚存在许多困难。本文分析结果显示,来流动压对缩比飞行试验具有显著影响。动压相似保证缩比飞机与原型机表现出相似的动力学特性,但同时也限制了缩比飞机的飞行性能。研究发现,对于本文中的高升阻比飞机,通过飞行方案设计,缩比飞机能够克服动压相似带来的约束,获得与原型机相仿甚至超过原型机的飞行性能,对后续开展其他缩比模型飞行试验具有一定的借鉴意义,同时可为我国低成本高性能靶标系统建设提供技术支持。

基于QAR着陆数据的跑道状况等级评估方法

跑道状况等级是飞机安全着陆的一个关键信息。为了进一步提高跑道状况评估的准确性和及时性,提出一种利用飞行快速存取记录器(Quick Access Recorder, QAR)数据快速评估跑道状况等级的方法。首先,根据飞行数据特征从繁多的数据中提取模型所需输入参数;其次,建立基于QAR数据建立飞机采用自动刹车着陆的动力学模型,并计算不同跑道状况等级对应的理论着陆距离;最后,将实际着陆距离与不同的跑道状况等级对应的理论着陆距离作对比,确定跑道状况等级。利用波音738和空客A320的QAR着陆数据分析某机场的跑道状况等级,并与该机场的雪情通告进行对比,验证了模型的准确性。研究成果可用于未来航班的着陆距离预测,为飞行员选择合适的刹车等级提供参考。

服务中国民航,成就中国机长——飞行性能课程思政探索

以“服务中国民航,成就中国机长”为教育目标,培养民航人“敬畏生命、敬畏规章、敬畏职责”的职业素养是飞行性能课程思政的主要元素,如何恰到好处地将其融入课堂教学和线上平台,是飞行性能课程思政建设的核心问题。本文分析了在飞行性能课程教学中进行课程思政教育的必要性,从教学设计、教学方法及教学实施等方面进行了课程思政的探索,实现了将传播知识、培养能力、引导思想和塑造价值观有机融合的教学理念。

梯度风场滑翔仿生飞行器设计与仿真

将信天翁从梯度风场中获取能量滑翔数千英里的飞行策略应用在飞行器上是突破飞行器续航瓶颈的重要方法之一。本文结合信天翁身体特性和飞行策略,设计了一种具有信天翁仿生外形、气动布局和控制方式的仿信天翁飞行器,巡航时升阻比为梯形翼飞行器的1.13倍,最大可达梯形翼飞行器升阻比的1.31倍,通过翼尖变形阻力最高可减小12%,翼根载荷减小35%。根据信天翁在滑翔时不时扑动翅膀的行为提出了间歇动力梯度风滑翔方法,对仿信天翁飞行器进行了风梯度滑翔操控性能仿真。结果表明实际飞行路径与风梯度滑翔路径的误差小于5%,能量消耗为匀速飞行的51.5%,验证了间歇动力梯度风滑翔策略的合理性。

复合露酒的非挥发性成分鉴定及抗疲劳效应

该研究采用高效液相色谱-四级杆飞行时间串联质谱联用(HPLC-Q-TOF-MS/MS)法对复合露酒(38%vol)中的非挥发性化合物进行检测,并将复合露酒灌胃至小鼠22 d,考察其对小鼠负重游泳的影响,评价其抗疲劳的保健作用。结果表明,从复合露酒(0.2257 g生药/mL)中共鉴定出52种非挥发性物质,包括皂苷类24种、黄酮类6种、核苷类4种、氨基酸类4种、生物碱类3种、其他11种。与模型组相比,低、中、高剂量组小鼠体质量减少量均极显著减少(P<0.01);中、高剂量组小鼠负重游泳时间均极显著延长(P<0.01);低、中剂量组小鼠血尿素氮(BUN)含量显著增加(P<0.01,P<0.05);低、中、高剂量组小鼠乳酸脱氢酶(LDH)活力、肝糖原(LG)含量显著增加(P<0.01,P<0.05),说明该款复合露酒非挥发性成分丰富,可增强身体对负荷的适应性,具有明显的抗疲劳效果,对功能性食品开发提供一定的基础。

超高效液相色谱-四极杆-飞行时间高分辨质谱用于化妆品中15种前列腺素类似物的快速筛查和测定

建立了超高效液相色谱-四极杆-飞行时间高分辨质谱(UPLC-Q-TOF MS)快速筛查和测定化妆品中15种前列腺素类似物的方法。样品以饱和氯化钠作为分散剂(蜡质类样品以四氢呋喃分散),经乙腈提取,离心取上清液过滤后,采用Poroshell 120 EC-C_(18)柱(150 mm×3.0 mm,2.7μm)分离,以5 mmol/L甲酸铵(含0.1%甲酸)-乙腈为流动相梯度洗脱。在ESI正离子模式下,采用Targeted MS/MS模式采集15种前列腺素类似物的质谱信息,构建筛查数据库进行快速筛查,确证后的目标物通过外标法定量。结果表明,15种前列腺素类似物的线性关系良好,相关系数(r^(2))均大于0.99;检出限为0.3~17.6μg/g,定量下限为1.1~58.8μg/g。在低、中、高3个加标水平下,水剂、膏霜、乳类、粉类、凝胶5类化妆品基质的回收率为70.1%~134%,相对标准偏差不大于7.5%。该方法简单高效、准确度好,可用于化妆品中前列腺素类似物的定性确证和定量分析,为化妆品风险识别提供技术支撑。