The coaxial compound helicopter has two possible strategies for heading control: collective differential and rudder deflection. A flight dynamics model is developed to assess the effect of different heading control st...The coaxial compound helicopter has two possible strategies for heading control: collective differential and rudder deflection. A flight dynamics model is developed to assess the effect of different heading control strategies. This includes the trim characteristics, steady flight performance,controllability, and manoeuvrability. The trim study demonstrates that heading control strategies are less influential on trim results, and the steady flight performance is also not significantly affected by the heading control strategy adopted. The controllability analysis shows although heading bandwidth and phase delay results at various speeds with different heading control strategies are all satisfied, the control derivative of the collective differential decreases as speed increases, and its heading aggressive agility is degraded into Level 3 in high-speed flight. In addition, using collective differential would lead to severe heading-rolling coupling as forward speed increases. On the contrary, the control derivative and aggressive agility of the rudder deflection is improved with forward speed, and there is no evidence of heading-rolling coupling. Finally, the transient turn MissionTask-Element(MTE) is utilized to investigate the heading manoeuvre characteristics in different heading control strategies, which indicates that the collective differential would add the amplitude of control input and the power consumption during this MTE.展开更多
This paper assesses the vehicle dynamics of a new cargo bike concept developed for euro pallet sized cargo. The cargo bike developed is for last-mile delivery. Different aspects of manoeuvrability and stability are ex...This paper assesses the vehicle dynamics of a new cargo bike concept developed for euro pallet sized cargo. The cargo bike developed is for last-mile delivery. Different aspects of manoeuvrability and stability are examined using a series of manoeuvres based on tests from the automotive industry combined with bicycle industry regulations. These manoeuvres objectively evaluate and determine the handling capabilities of the cargo bike concept. Those tests can be compared using the results of the benchmark vehicles. The results conclude the new cargo bike has proper vehicle dynamics above the majority of benchmark vehicles but there is still room for improvement.展开更多
This study creates and combines the general maneuver libraries for fixed-wing aircraft to implement tactical maneuvers.First,the generalized maneuver libraries are established by analyzing the characteristics of tacti...This study creates and combines the general maneuver libraries for fixed-wing aircraft to implement tactical maneuvers.First,the generalized maneuver libraries are established by analyzing the characteristics of tactical maneuvers required in battlefields.The 7th order polynomial is applied to both the creation of the maneuver libraries and the generation of the trajectories or flight paths for modal inputs.To track the desired trajectory,we design the Attitude Command Attitude Hold(ACAH)system and the Rate Command Rate Hold(RCRH)system using Model Following Controller(MFC).Moreover,the Line-of-Sight(LOS)guidance law is designed.In particular,the CONDUIT~?is employed to optimize the gains so that the control systems meet the aircraft Handling Qualities(HQ)criteria.Finally,flight simulations are performed for the longitudinal loop,immelmann-turn,and climb-slalom-descent maneuvers to verify that tactical aggressive maneuvers are realizable via the combination of maneuver libraries.This study can contribute to the development of flight techniques for aircraft tactical maneuvers and to the revision of air force operational manuals.展开更多
俄ЦАГИ在地面飞行模拟试验和飞行试验数据的统计分析基础上,提出了一个频域最佳C*响应操纵灵敏度——A值的概念,并找出了驾驶杆特性(pχ)和静态操纵灵敏度(pny、χny)最佳值与A值的表达式,以及它们偏离最佳值时飞行品质评分(PR)与...俄ЦАГИ在地面飞行模拟试验和飞行试验数据的统计分析基础上,提出了一个频域最佳C*响应操纵灵敏度——A值的概念,并找出了驾驶杆特性(pχ)和静态操纵灵敏度(pny、χny)最佳值与A值的表达式,以及它们偏离最佳值时飞行品质评分(PR)与人机耦合振荡(PIO)评分(PIOR)随相对偏离量的关系曲线。 A 将此关系曲线用于预测评估人感系统相关参数对PIO趋势的影响,称之为A准则。本文从应用的角度详细地进行了计算公式的推导,讨论了准则在推导过程中所采用的假设和其适用情况,重新整理和校核了计算步骤和算例,以便于我国航空界使用。展开更多
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions of China, the program of China Scholarships Council (No. 201706830016)the National Natural Science Foundation of China (No. 11672128)
文摘The coaxial compound helicopter has two possible strategies for heading control: collective differential and rudder deflection. A flight dynamics model is developed to assess the effect of different heading control strategies. This includes the trim characteristics, steady flight performance,controllability, and manoeuvrability. The trim study demonstrates that heading control strategies are less influential on trim results, and the steady flight performance is also not significantly affected by the heading control strategy adopted. The controllability analysis shows although heading bandwidth and phase delay results at various speeds with different heading control strategies are all satisfied, the control derivative of the collective differential decreases as speed increases, and its heading aggressive agility is degraded into Level 3 in high-speed flight. In addition, using collective differential would lead to severe heading-rolling coupling as forward speed increases. On the contrary, the control derivative and aggressive agility of the rudder deflection is improved with forward speed, and there is no evidence of heading-rolling coupling. Finally, the transient turn MissionTask-Element(MTE) is utilized to investigate the heading manoeuvre characteristics in different heading control strategies, which indicates that the collective differential would add the amplitude of control input and the power consumption during this MTE.
文摘This paper assesses the vehicle dynamics of a new cargo bike concept developed for euro pallet sized cargo. The cargo bike developed is for last-mile delivery. Different aspects of manoeuvrability and stability are examined using a series of manoeuvres based on tests from the automotive industry combined with bicycle industry regulations. These manoeuvres objectively evaluate and determine the handling capabilities of the cargo bike concept. Those tests can be compared using the results of the benchmark vehicles. The results conclude the new cargo bike has proper vehicle dynamics above the majority of benchmark vehicles but there is still room for improvement.
基金High-Speed Compound Unmanned Rotorcraft(HCUR)research laboratory with the support of Agency for Defense Development(ADD).
文摘This study creates and combines the general maneuver libraries for fixed-wing aircraft to implement tactical maneuvers.First,the generalized maneuver libraries are established by analyzing the characteristics of tactical maneuvers required in battlefields.The 7th order polynomial is applied to both the creation of the maneuver libraries and the generation of the trajectories or flight paths for modal inputs.To track the desired trajectory,we design the Attitude Command Attitude Hold(ACAH)system and the Rate Command Rate Hold(RCRH)system using Model Following Controller(MFC).Moreover,the Line-of-Sight(LOS)guidance law is designed.In particular,the CONDUIT~?is employed to optimize the gains so that the control systems meet the aircraft Handling Qualities(HQ)criteria.Finally,flight simulations are performed for the longitudinal loop,immelmann-turn,and climb-slalom-descent maneuvers to verify that tactical aggressive maneuvers are realizable via the combination of maneuver libraries.This study can contribute to the development of flight techniques for aircraft tactical maneuvers and to the revision of air force operational manuals.
文摘俄ЦАГИ在地面飞行模拟试验和飞行试验数据的统计分析基础上,提出了一个频域最佳C*响应操纵灵敏度——A值的概念,并找出了驾驶杆特性(pχ)和静态操纵灵敏度(pny、χny)最佳值与A值的表达式,以及它们偏离最佳值时飞行品质评分(PR)与人机耦合振荡(PIO)评分(PIOR)随相对偏离量的关系曲线。 A 将此关系曲线用于预测评估人感系统相关参数对PIO趋势的影响,称之为A准则。本文从应用的角度详细地进行了计算公式的推导,讨论了准则在推导过程中所采用的假设和其适用情况,重新整理和校核了计算步骤和算例,以便于我国航空界使用。
