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71.
基于能量优化的无人机机动能够使无人机在不失去决定性位置优势的情况下获取相对于对手的能量优势,足够的能量优势可转换为有效的位置优势,有利于无人机在空战中随时改出当前机动并投入下一机动动作,对于无人机获取空战胜利至关重要。开展了基于能量优化的无人机机动轨迹生成方法研究,通过在无人机机动飞行包线内设计合适的机动指令,使得无人机能量性能指标最优。以上升转弯机动为例进行了机动轨迹生成的详细设计,并与常规上升转弯机动轨迹生成结果进行对比,仿真结果显示所设计的机动动作完成时间缩短了28.6%~83.8%,总能量变化减少了64.7%~70.1%,实现了无人机机动飞行的能量优化。 相似文献
72.
针对小型无人机飞控系统在功耗、成本、可靠性以及集成度等方面的较高要求,设计了一种基于Freescale M56F807型DSP和PID控制策略的飞控系统。针对某型号的无人机,详细阐述了系统的设计思想及其基本硬件和软件结构。采用了时域信号的取样积累平均方法,减少了算法的实现难度,提高了采样精度。对硬件设计中的关键技术进行了研究,系统具有设计精炼,可靠性高,开放性好等优点。基于DSP的现代高速数字处理飞控系统,能够赋予无人机更大的机动性、更高的灵活性和更广泛的适用性。 相似文献
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77.
Three-dimensional path planning for unmanned aerial vehicle based on interfered fluid dynamical system 总被引:1,自引:0,他引:1
This paper proposes a method for planning the three-dimensional path for low-flying unmanned aerial vehicle(UAV) in complex terrain based on interfered fluid dynamical system(IFDS) and the theory of obstacle avoidance by the flowing stream. With no requirement of solutions to fluid equations under complex boundary conditions, the proposed method is suitable for situations with complex terrain and different shapes of obstacles. Firstly, by transforming the mountains, radar and anti-aircraft fire in complex terrain into cylindrical, conical, spherical, parallelepiped obstacles and their combinations, the 3D low-flying path planning problem is turned into solving streamlines for obstacle avoidance by fluid flow. Secondly, on the basis of a unified mathematical expression of typical obstacle shapes including sphere, cylinder, cone and parallelepiped, the modulation matrix for interfered fluid dynamical system is constructed and 3D streamlines around a single obstacle are obtained. Solutions to streamlines with multiple obstacles are then derived using weighted average of the velocity field. Thirdly, extra control force method and virtual obstacle method are proposed to deal with the stagnation point and the case of obstacles’ overlapping respectively. Finally, taking path length and flight height as sub-goals, genetic algorithm(GA) is used to obtain optimal 3D path under the maneuverability constraints of the UAV. Simulation results show that the environmental modeling is simple and the path is smooth and suitable for UAV. Theoretical proof is also presented to show that the proposed method has no effect on the characteristics of fluid avoiding obstacles. 相似文献
78.
《中国航空学报》2020,33(11):2825-2827
With the rapid development of Unmanned Aerial Vehicle (UAV) technology, one of the emerging fields is to utilize multi-UAV as a team under autonomous control in a complex environment. Among the challenges in fully achieving autonomous control, Cooperative task assignment stands out as the key function. In this paper, we analyze the importance and difficulties of multi-UAV cooperative task assignment in characterizing scenarios and obtaining high-quality solutions. Furthermore, we present three promising directions for future research: Cooperative task assignment in a dynamic complex environment, in an unmanned-manned aircraft system and in a UAV swarm. Our goal is to provide a brief review of multi-UAV cooperative task assignment for readers to further explore. 相似文献
79.
针对大中型无人机系统实现远程测控与信息传输的技术需求,在参考国外"捕食者"、"全球鹰"等先进无人机系统技术体制和实现方案的基础上,提出了利用商业或军用通信卫星作为空中中继平台,建立无人机卫星中继数据链,实现我国远程无人机系统的超视距遥控、遥测和侦察信息实时传输的解决方案,这对延伸无人机系统的作用距离、提高作战效能具有重要意义。文中分析了无人机系统卫星中继数据链的技术体制,提出了工程应用中的关键技术,对具体的工程实现具有一定的指导意义。 相似文献
80.
《中国航空学报》2021,34(3):129-144
In this paper, an Unmanned Aerial Vehicle (UAV)-assisted relay communication system is studied, where a UAV is served as a flying relay to maintain a communication link between a mobile source node and a remote destination node. Specifically, an average outage probability minimization problem is formulated firstly, with the constraints on the transmission power of the source node, the maximum energy consumption budget, the transmission power, the speed and acceleration of the flying UAV relay. Next, the closed-form of outage probability is derived, under the hybrid line-of-sight and non-line-of-sight probability channel model. To deal with the formulated nonconvex optimization, a long-term proactive optimization mechanism is developed. In particular, firstly, an approximation for line-of-sight probability and a reformulation of the primal problem are given, respectively. Then, the reformulated problem is transformed into two subproblems: one is the transmission power optimization with given UAV’s trajectory and the other is the trajectory optimization with given transmission power allocation. Next, two subproblems are tackled via tailoring primal–dual subgradient method and successive convex approximation, respectively. Furthermore, a proactive optimization algorithm is proposed to jointly optimize the transmission power allocation and the three-dimensional trajectory. Finally, simulation results demonstrate the performance of the proposed algorithm under various parameter configurations. 相似文献