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A Software-in-the-Loop Implementation of Adaptive Formation Control for Fixed-Wing UAVs 被引量:5
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作者 Jun Yang Ximan Wang +2 位作者 Simone Baldi Satish Singh Stefano Fari 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1230-1239,共10页
This paper discusses the design and software-in-theloop implementation of adaptive formation controllers for fixedwing unmanned aerial vehicles(UAVs) with parametric uncertainty in their structure, namely uncertain ma... This paper discusses the design and software-in-theloop implementation of adaptive formation controllers for fixedwing unmanned aerial vehicles(UAVs) with parametric uncertainty in their structure, namely uncertain mass and inertia. In fact, when aiming at autonomous flight, such parameters cannot assumed to be known as they might vary during the mission(e.g.depending on the payload). Modeling and autopilot design for such autonomous fixed-wing UAVs are presented. The modeling is implemented in Matlab, while the autopilot is based on ArduPilot, a popular open-source autopilot suite. Specifically, the ArduP ilot functionalities are emulated in Matlab according to the Ardupilot documentation and code, which allows us to perform software-in-the-loop simulations of teams of UAVs embedded with actual autopilot protocols. An overview of realtime path planning, trajectory tracking and formation control resulting from the proposed platform is given. The software-inthe-loop simulations show the capability of achieving different UAV formations while handling uncertain mass and inertia. 展开更多
关键词 ArduPilot ADAPTIVE formation control fixed-wing UAVs software-in-the-loop simulations
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Radio Controlled “3D Aerobatic Airplanes” as Basis for Fixed-Wing UAVs with VTOL Capability 被引量:1
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作者 Chung-How Poh Chung-Kiak Poh 《Open Journal of Applied Sciences》 2014年第12期515-521,共7页
There are fundamental performance compromises between rotary-wing and fixed-wing UAVs. The general solution to address this well-known problem is the design of a platform with some degree of reconfigurable airframes. ... There are fundamental performance compromises between rotary-wing and fixed-wing UAVs. The general solution to address this well-known problem is the design of a platform with some degree of reconfigurable airframes. For critical missions (civilian or military), it is imperative that mechanical complexity is kept to a minimum to help achieve mission success. This work proposes that the tried-and-true radio controlled (RC) aerobatic airplanes can be implemented as basis for fixed-wing UAVs having both speed and vertical takeoff and landing (VTOL) capabilities. These powerful and highly maneuverable airplanes have non-rotatable nacelles, yet capable of deep stall maneuvers. The power requirements for VTOL and level flight of an aerobatic RC airplane are evaluated and they are compared to those of a RC helicopter of similar flying weight. This work provides quantitative validation that commercially available RC aerobatic airplanes can serve as platform to build VTOL capable fixed-wing UAVs that are agile, cost effective, reliable and easy maintenance. 展开更多
关键词 Aerobatics Unmanned AERIAL Vehicle fixed-wing VTOL HOVER
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Retarded Harrier Maneuver as a New and Efficient Approach for Fixed-Wing Aircraft to Achieve S/VTOL
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作者 Chung-Kiak Poh Chung-How Poh 《Advances in Aerospace Science and Technology》 2021年第2期81-92,共12页
Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span styl... Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span style="font-family:Verdana;"> com</span><span style="font-family:Verdana;">pared to tilt-wings or tilt-rotors in the pre-80’s era. Radio-controlled </span><span style="font-family:Verdana;">aerobatic airplanes have thrust-to-weight ratio of greater than unity and are capable of performing a range of impressive maneuvers including the so-called harrier maneuver. We hereby present a new maneuver known as the retarded harrier </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">that is applicable to un/manned fixed-wing aircraft for achieving VTOL flight with a better forward flight performance than a quadplane in terms of weight, speed and esthetics.</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> An airplane with tandem roto-stabilizers is also presented as an efficient airframe to achieve VTOL via retarded harrier maneuver, and detailed analysis is given for hovering at 45° and 60° and comparison is made against the widely adopted quadplane. This work also includes experimental demonstration of retarded harrier maneuver using a small remotely pilot airplane of wingspan 650 mm.</span></span></span> 展开更多
关键词 fixed-wing Aircraft Roto-Stabilizer Vertical Takeoff and Landing Short Takeoff Harrier Maneuver Distributed VTOL System (DVS) Urban Air Mo-bility (UAM)
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关节镜下外-内缝合法结合Fast-Fix系统治疗膝关节盘状半月板外侧撕裂伤 被引量:8
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作者 胡月正 温宏 +3 位作者 潘孝云 张宇 陈成旺 余华晨 《中医正骨》 2011年第12期42-44,共3页
膝关节盘状半月板在东方人种中多见,由于其充填并占据胫股关节间隙,不仅影响膝关节活动,而且易于受到挤压、扭转等暴力而导致损伤。盘状半月板损伤以分层损伤为主,部分患者合并有外侧边缘撕裂伤。
关键词 关节镜检查 半月板 胫骨撕裂伤外-内缝合法 Fast—fix
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基于Super-Twisting滑模S面的无人机路径跟踪控制
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作者 张国兵 石上瑶 +2 位作者 李佳成 常哲 陈鹏云 《火力与指挥控制》 CSCD 北大核心 2024年第2期11-17,共7页
针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控... 针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控制。考虑到S面控制求导易导致积分爆炸的问题引入了二阶微分器,并对外界风组成进行建模研究。最后通过空间特殊曲线来验证所设计算法的控制性能。仿真结果表明,所设计的算法可以实现固定翼无人机对期望路径的精确跟踪,并具有良好的鲁棒性和抗干扰性能。 展开更多
关键词 固定翼无人机 Super-Twisting滑模 S面控制 风干扰
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Wing kinematics measurement and aerodynamics of free-flight maneuvers in drone-flies 被引量:11
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作者 Yanlai Zhang Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第3期371-382,共12页
The time courses of wing and body kinematics of two free-flying drone-flies, as they performed saccades, were measured using 3D high-speed video, and the morpho- logical parameters of the wings and body of the insects... The time courses of wing and body kinematics of two free-flying drone-flies, as they performed saccades, were measured using 3D high-speed video, and the morpho- logical parameters of the wings and body of the insects were also measured. The measured wing kinematics was used in a Navier-Stokes solver to compute the aerodynamic forces and moments acting on the insects. The main results are as following. (1) The turn is mainly a 90° change of heading. It is made in about 10 wingbeats (about 55 ms). It is of interest to note that the number of wingbeats taken to make the turn is approximately the same as and the turning time is only a little different from that of fruitflies measured recently by the same approach, even if the weight of the droneflies is more than 100 times larger than that of the fruitflies. The long axis of body is about 40° from the horizontal during the maneuver. (2) Although the body rotation is mainly about a vertical axis, a relatively large moment around the yaw axis (axis perpendicular to the long axis of body), called as yaw moment, is mainly needed for the turn, because moment of inertial of the body about the yaw axis is much larger than that about the long axis. (3) The yaw moment is mainly pro- duced by changes in wing angles of attack: in a right turn, for example, the dronefly lets its right wing to have a rather large angle of attack in the downstroke (generally larger than 50°) and a small one in the upstroke to start the turn, and lets its left wing to do so to stop the turn, unlike the fruitflies who generate the yaw moment mainly by changes in the stroke plane and stroke amplitude. 展开更多
关键词 Drone-fly - Maneuver wing kinematicsmeasurement AERODYNAMICS Navier-Stokes simulation
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Optimization Design for Fixed Table of Gantry Machining Center Based on Sensitivity and Topology Analyses 被引量:3
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作者 郑彬 殷国富 +2 位作者 黄辉 陈强 方辉 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期263-268,共6页
In order to decrease the deformation and stress and increase the natural frequency of the fixed table,a method of optimization driven by the sensitivity and topology analyses is proposed.The finite element model of th... In order to decrease the deformation and stress and increase the natural frequency of the fixed table,a method of optimization driven by the sensitivity and topology analyses is proposed.The finite element model of the fixed table is constructed and analyzed by using ANSYS software.Based on the results of static analysis and modal analysis,the maximum deformation,the maximum stress,and natural frequencies are obtained.Then,the sensitivity analysis and topology optimization are carried out to find out the parameters to be optimized.The fixed table is reconstructed according to optimal design scheme.In the comparison of the results between original model and the optimized one,the maximum deformation and stress are decreased by 71.73%and 60.27%respectively.At the same time,the natural frequencies from the first mode to the sixth mode are increased by 30.28%,29.57%,29.51%,31.52%,22.19%,and 21.80%,respectively.The method can provide technology guide for the design and optimization of machining structure. 展开更多
关键词 gantry machining center sensitivity analysis topology optimization optimization design fixed tableCLC number:TG502Document code:AArticle ID:1672-5220(2013)04-0263-06
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基于终端滑模的F-16固定翼飞行器有限时间编队控制
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作者 辛颖 姜斌 +2 位作者 冒泽慧 吕迅竑 马亚杰 《控制工程》 CSCD 北大核心 2024年第6期973-980,共8页
以F-16固定翼飞行器为研究对象,采用终端滑模控制方法,实现了六自由度固定翼飞行器的有限时间编队控制。首先,根据奇异摄动理论,将固定翼飞行器十二阶微分运动方程按照响应速度快慢分为外环位置编队控制系统和内环姿态跟踪控制系统。外... 以F-16固定翼飞行器为研究对象,采用终端滑模控制方法,实现了六自由度固定翼飞行器的有限时间编队控制。首先,根据奇异摄动理论,将固定翼飞行器十二阶微分运动方程按照响应速度快慢分为外环位置编队控制系统和内环姿态跟踪控制系统。外环应用有限时间稳定性理论和非线性滑模控制方法设计了分布式控制器,实现多固定翼飞行器系统的有限时间编队控制。然后,将外环分布式控制器产生的控制信号转换为内环单架固定翼飞行器的姿态跟踪参考信号,内环应用非线性动态逆(nonlinear dynamic inversion,NDI)控制和增量非线性动态逆(incremental nonlinear dynamic inversion,INDI)控制在可能存在执行器故障的情况下实现单架固定翼飞行器姿态的跟踪控制。最后,通过仿真实例验证了该控制方法的有效性。 展开更多
关键词 有限时间稳定 固定翼编队控制 滑模控制 增量非线性动态逆
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Fixed Point Theorems of the Iterated Function Systems
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作者 Ji You-qing Liu Zhi Ri Song-il 《Communications in Mathematical Research》 CSCD 2016年第2期142-150,共9页
In this paper, we present some fixed point theorems of iterated function systems consisting of α-ψ-contractive type mappings in Fractal space constituted by the compact subset of metric space and iterated function s... In this paper, we present some fixed point theorems of iterated function systems consisting of α-ψ-contractive type mappings in Fractal space constituted by the compact subset of metric space and iterated function systems consisting of Banach contractive mappings in Fractal space constituted by the compact subset of generalized metric space, which is Mso extensively applied in topological dynamic system. 展开更多
关键词 fixed point α-ψ-contractive mapping iterated function system gener-alized metric space
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Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds
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作者 Hao LU Lan GAO +2 位作者 Yunda YAN Mingzhe HOU Chenliang WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第2期431-445,共15页
Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight path.To cope with various wind conditions,this paper proposes a wind disturbance compensated path following... Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight path.To cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the inner-loop.Since the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal components.Moreover,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector field.High-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds. 展开更多
关键词 Path following Guiding vector field Wind disturbance Disturbance rejection fixed wings
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西黄胶囊联合TP方案对晚期非小细胞肺癌患者血清Foxp3、Ang-2水平的影响 被引量:7
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作者 刘小红 杨庆辉 +2 位作者 张永恒 王荦楠 袁红昌 《世界中西医结合杂志》 2022年第6期1214-1217,1222,共5页
目的探讨西黄胶囊联合TP方案治疗晚期非小细胞肺癌患者的临床疗效。方法选取2017年6月—2019年6月期间新乡医学院第一附属医院收治的晚期非小细胞肺癌患者86例,采用随机摸球法分为对照组和治疗组,每组各43例。对照组采用TP方案化疗,治... 目的探讨西黄胶囊联合TP方案治疗晚期非小细胞肺癌患者的临床疗效。方法选取2017年6月—2019年6月期间新乡医学院第一附属医院收治的晚期非小细胞肺癌患者86例,采用随机摸球法分为对照组和治疗组,每组各43例。对照组采用TP方案化疗,治疗组在此基础上加用西黄胶囊治疗。两组患者均连续治疗42 d后,观察两组患者近期疗效及不良反应发生情况,同时观察两组患者治疗前后中医证候症状积分、血清叉头翼状螺旋转录因子3(Forkhead or winged helix transcription,Foxp3)、血管生成素-2(Angiopoietin-2,Ang-2)、美国东部肿瘤协作组体能状况(Eastern cooperative oncology group performance status,ECOGPS)评分变化。结果治疗后治疗组有效率为46.51%、疾病控制率为83.72%,与对照组有效率25.38%、疾病控制率65.12%比较,差异有统计学意义(P<0.05)。治疗后,两组患者咳嗽、气短、胸闷、出汗、乏力、畏寒肢冷、腰膝酸软积分及总分较治疗前均降低,差异有统计学意义(P<0.05);且治疗组低于对照组,差异有统计学意义(P<0.05)。治疗后两组患者血清Foxp3、Ang-2水平较治疗前明显降低,差异有统计学意义(P<0.05);且治疗组低于对照组,差异有统计学意义(P<0.05)。治疗后两组ECOGPS评分均较治疗前降低,差异有统计学意义(P<0.05);且治疗组低于对照组(P<0.05)。治疗组发热(30.23%)、恶心呕吐(30.23%)、血小板减少(34.88%)、白细胞减少(41.86%)及肝肾功能损伤(30.23%)发生率与对照组(53.49%、60.47%、55.81%、48.84%、44.19%)比较,差异有统计学意义(P<0.05)。结论西黄胶囊联合TP方案治疗NSCLC的效果显著,能明显改善患者临床症状及体能状况,减轻化疗毒副反应,并降低血清Foxp3、Ang-2表达水平发挥抗癌作用。 展开更多
关键词 西黄胶囊 TP方案 晚期非小细胞肺癌 叉头翼状螺旋转录因子3(forkhead or winged helix transcription Foxp3) 血管生成素-2(angiopoietin-2 Ang-2)
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基于N-S方程的地面效应数值模拟研究 被引量:10
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作者 岳锋 石亚军 李凤蔚 《航空计算技术》 2005年第2期62-65,共4页
研究了二维翼型在两种不同地面条件-移动地面和固定地面条件下的地面效应及流动特性问题。其中流场分析采用了不可压缩RANS方程,湍流模型采用Spalart-Allmaras一方程湍流模型。通过对NACA4412翼型在两种不同的地面条件及不同迎角和不同... 研究了二维翼型在两种不同地面条件-移动地面和固定地面条件下的地面效应及流动特性问题。其中流场分析采用了不可压缩RANS方程,湍流模型采用Spalart-Allmaras一方程湍流模型。通过对NACA4412翼型在两种不同的地面条件及不同迎角和不同地面高度情况下的绕流计算,结果表明,在两种不同的地面条件下,升力及力矩的差别较小,而固定地面条件的阻力略小于移动地面条件下的阻力。 展开更多
关键词 二维翼型 地面效应 固定地面 移动地面
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抗组胺药对慢性荨麻疹患者血浆TAT与FIX水平的影响 被引量:3
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作者 梁碧华 李润祥 +3 位作者 林路洋 龚业青 李振洁 朱慧兰 《中国麻风皮肤病杂志》 2013年第7期444-446,共3页
目的:观察抗组胺药对慢性荨麻疹(CU)患者血浆凝血酶-抗凝血酶复合物(TAT)与凝血因子Ⅸ(FIX)水平的影响并探讨TAT、FIX与CU发病的关系。方法:用酶联免疫吸附法检测治疗前CU患者、抗组胺治疗症状控制后CU以及健康献血者血浆TAT与FIX的水... 目的:观察抗组胺药对慢性荨麻疹(CU)患者血浆凝血酶-抗凝血酶复合物(TAT)与凝血因子Ⅸ(FIX)水平的影响并探讨TAT、FIX与CU发病的关系。方法:用酶联免疫吸附法检测治疗前CU患者、抗组胺治疗症状控制后CU以及健康献血者血浆TAT与FIX的水平。结果:CU患者治疗前的血浆TAT水平(32.13±14.72 ng/mL)明显高于正常对照组(21.94±7.95 ng/mL)(P<0.01),抗组胺治疗症状控制后的血浆TAT水平(26.53±14.43 ng/mL)较治疗前下降,但组间比较无统计学差异(P>0.05);CU患者治疗前的血浆FIX水平(2.32±0.77μg/mL)低于正常对照组(4.25±1.16μg/mL)(P<0.01),抗组胺治疗症状控制后的血浆FIX水平(3.02±1.36 ng/mL)较治疗前升高(P<0.01),但尚低于正常对照组(P<0.01)。结论:CU患者血浆TAT水平升高,FIX水平降低,提示CU患者存在凝血系统激活以及FIX消耗,抗组胺药治疗后CU患者体内凝血状态向正常水平方向改变,但短时间用药症状控制后其凝血状态并不能立即恢复正常水平。 展开更多
关键词 慢性荨麻疹 凝血酶-抗凝血酶复合物(TAT) 凝血因子IX(fix)
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二连-东乌旗地区固定翼三频航电数据反演方法应用对比研究 被引量:1
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作者 李飞 谭捍东 +2 位作者 孟庆敏 吴俊彦 丁志强 《物探与化探》 CAS 北大核心 2020年第5期1172-1182,共11页
固定翼频率域航电测量效率高,空间分辨率高。以往我国三频航电实测数据已获得良好的解释成果,但均以定性解释和一维反演为主,二维反演应用较少。本文将快速近似反演、一维反演、二维反演引入到二连-东乌旗重点航电异常实测数据的解释中... 固定翼频率域航电测量效率高,空间分辨率高。以往我国三频航电实测数据已获得良好的解释成果,但均以定性解释和一维反演为主,二维反演应用较少。本文将快速近似反演、一维反演、二维反演引入到二连-东乌旗重点航电异常实测数据的解释中,并将三种方法的应用效果进行了对比。快速近似反演以视电阻率计算为基础,一维反演采用Brent方法,二维反演采用数据空间Occam反演,采用Rodi法求解雅克比矩阵。结果显示,快速近似反演可快速有效地提供大数据量地下电性分布信息,一维反演可提供稳定的、具一定深度的反演结果,二维反演则具有明显的横向、纵向分辨率优势。 展开更多
关键词 固定翼三频航电 快速近似反演 一维反演 二维反演 二连—东乌旗
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The effects of corrugation and wing planform on the aerodynamic force production of sweeping model insect wings 被引量:13
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作者 Guoyu Luo Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期531-541,共11页
The effects of corrugation and wing planform (shape and aspect ratio) on the aerodynamic force production of model insect wings in sweeping (rotating after an initial start) motion at Reynolds number 200 and 3500 ... The effects of corrugation and wing planform (shape and aspect ratio) on the aerodynamic force production of model insect wings in sweeping (rotating after an initial start) motion at Reynolds number 200 and 3500 at angle of attack 40℃ are investigated, using the method of computational fluid dynamics. A representative wing corrugation is considered. Wing-shape and aspect ratio (AR) of ten representative insect wings are considered; they are the wings of fruit fly, cranefly, dronefly, hoverfly, ladybird, bumblebee, honeybee, lacewing (forewing), hawkmoth and dragon- fly (forewing), respectively (AR of these wings varies greatly, from 2.84 to 5.45). The following facts are shown. (1) The corrugated and flat-plate wings produce approximately the same aerodynamic forces. This is because for a sweeping wing at large angle of attack, the length scale of the corrugation is much smaller than the size of the separated flow region or the size of the leading edge vortex (LEV). (2) The variation in wing shape can have considerable effects on the aerodynamic force; but it has only minor effects on the force coefficients when the velocity at r2 (the radius of the second :moment of wing area) is used as the reference velocity; i.e. the force coefficients are almost unaffected by the variation in wing shape. (3) The effects of AR are remarkably small: whenAR increases from 2.8 to 5.5, the force coefficients vary only slightly; flowfield results show that when AR is relatively large, the part of the LEV on the outer part of the wings sheds during the sweeping motion. As AR is increased, on one hand, the force coefficients will be increased due to the reduction of 3-dimensional flow effects; on the other hand, they will be decreased due to the shedding of part of the LEV; these two effects approximately cancel each other, resulting in only minor change of the force coefficients. 展开更多
关键词 insect flight - Sweeping wing Unsteady aerodynamics wing corrugation Planform
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浅谈纵横无人机CW-10在山区测图中的应用 被引量:1
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作者 卢敏 郑金秀 《测绘与空间地理信息》 2021年第2期187-188,192,共3页
近年来,无人机行业在测绘领域迅速发展并广泛应用,市场上以单纯的固定翼或旋翼类型无人机居多,本文以纵横公司固定翼加旋翼组合的CW10无人机为搭载平台,以贵州铜仁某处山区地形为例,进行实际应用,测试其在地形起伏较大的区域执行测绘任... 近年来,无人机行业在测绘领域迅速发展并广泛应用,市场上以单纯的固定翼或旋翼类型无人机居多,本文以纵横公司固定翼加旋翼组合的CW10无人机为搭载平台,以贵州铜仁某处山区地形为例,进行实际应用,测试其在地形起伏较大的区域执行测绘任务的能力。文中设定了不同飞行高度,测试其在不同成图比例尺下的成图精度,同时考虑电池的续航里程,找出最优执行方案设计、航线设计等注意事项,方便实际操作人员高效完成现场航测任务规划,合理利用电池电量,并保障无人机安全顺利完成作业。 展开更多
关键词 无人机 固定翼加旋翼 最优方案
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空中-水面子母无人平台系统设计与协同控制 被引量:3
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作者 张洺溪 谷丰 +3 位作者 何玉庆 狄春雷 褚玲玲 聂虹宇 《无人系统技术》 2021年第4期85-96,共12页
微小型固定翼无人机和水面无人船组成的子母型无人系统是一种典型的跨域异构协同实现方式,开展有针对性的相关研究可快速提升我军现有无人装备技术水平。首先,介绍了国内外空中-水面子母无人平台系统的研究进展;其次,针对舰载固定翼无... 微小型固定翼无人机和水面无人船组成的子母型无人系统是一种典型的跨域异构协同实现方式,开展有针对性的相关研究可快速提升我军现有无人装备技术水平。首先,介绍了国内外空中-水面子母无人平台系统的研究进展;其次,针对舰载固定翼无人机难回收的问题提出了一种全新的跨域异构协作的实现方式:利用可变柔性机械臂配合拦阻索的机构辅助实现在狭小空间和恶劣条件下对微小型固定翼无人机平台的自主释放与回收,并详细介绍了该子母系统;然后,搭建半物理仿真平台、开发原理样机,分别在实现了半物理仿真以及真实水面环境下实现了空中-水面子母无人平台系统的协同控制以及全自主循环释放与回收试验;最后,该试验验证了该空中-水面异构平台系统作为一种跨域协作实现方式的可行性。该空中-水面子母无人平台以高成功率的方式实现了全自主循环释放与回收,对未来大型舰载固定翼无人机与无人船实现跨域协同具有借鉴意义。 展开更多
关键词 子母系统 跨域协作 协同控制 自主起降 微小型固定翼 异构
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基于UIF-MPC仿真的UAV环航姿态控制研究 被引量:1
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作者 朱代武 刘豪 +1 位作者 路东林 鲁力 《火力与指挥控制》 CSCD 北大核心 2023年第5期158-163,共6页
为解决无人机(unmanned aerial vehicle,UAV)在算法结构冗杂和未知外部干扰的环境下控制系统操作难度大的问题,提出一种基于UIF-MPC融合的自适应全局快速终端滑模控制方法。考虑到在环境复杂、时间敏感及通信受限条件下给出UAV姿态运动... 为解决无人机(unmanned aerial vehicle,UAV)在算法结构冗杂和未知外部干扰的环境下控制系统操作难度大的问题,提出一种基于UIF-MPC融合的自适应全局快速终端滑模控制方法。考虑到在环境复杂、时间敏感及通信受限条件下给出UAV姿态运动观测模型;提出一种多控制变量交互的UIF-MPC融合滤波姿态算法,利用滤波器和PID控制器对模型不确定性和未知干扰进行补偿;根据UAV性能及饱和控制条件设定姿态设定控制参数并设定目标位置估计均方根误差,带入UIF-MPC模型并与传统单UIF模型进行比较。结果表明UIF-MPC融合模型可以较好融合系统需求,且在运动过程中具有较好的估计精度及机动控制的鲁棒性。 展开更多
关键词 固定翼无人机 信息滤波 模型预测控制 环航姿态 控制器
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Prediction of electric-powered fixed-wing UAV endurance 被引量:2
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作者 CHENG Feng WANG Hua CUI Pin 《航空动力学报》 EI CAS CSCD 北大核心 2017年第9期2170-2179,共10页
To overcome the problems encountered in predicting the endurance of electricpowered fixed-wing unmanned aerial vehicles(UAVs),which were stemmed from the dynamic changes in electric power system efficiency and battery... To overcome the problems encountered in predicting the endurance of electricpowered fixed-wing unmanned aerial vehicles(UAVs),which were stemmed from the dynamic changes in electric power system efficiency and battery discharge characteristics under different operating conditions,the required battery power model and battery discharge model were studied.The required battery power model was determined using an approximate model of electric power system efficiency based on wind tunnel testing and the self-adaptive penalty function.Furthermore,current correction and ambient temperature correction terms were proposed for the trained Kriging model representing the discharge characteristics under standard operation,and then the discharged capacity-terminal voltage model was established.Through numerical integration of this model with the required battery power model,the electric-powered fixed-wing UAV endurance prediction model was obtained.Laboratory tests indicated that the proposed endurance model could precisely calculate the battery discharge time and accurately describe the battery discharge process.The similarity of the theoretical and flight test results reflected the accuracy of the proposed endurance model as well as the importance of considering dynamic changes in power system efficiency in endurance calculations.The proposed endurance model meeting precision requirements can be used in practical engineering applications. 展开更多
关键词 fixed-wing unmanned aerial vehicle(UAV) ENDURANCE Peukert equation self-adaptive penalty function power system efficiency
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Energy-efficiency maximization for fixed-wing UAV-enabled relay network with circular trajectory
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作者 Chenxiao XIE Xin-Lin HUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第9期71-80,共10页
With the development of Unmanned Aerial Vehicles(UAVs), the applications of UAVs have been extensively explored. In the field of wireless communications, the relay nodes are often used to extend network coverage. Howe... With the development of Unmanned Aerial Vehicles(UAVs), the applications of UAVs have been extensively explored. In the field of wireless communications, the relay nodes are often used to extend network coverage. However, traditional fixed ground relays cannot be flexibly deployed due to their low heights and fixed locations. Hence, deploying UAV as relay node is a promising solution and has become a research hotspot. In this paper, we consider an UAVenabled relaying network in which a fixed-wing UAV is deployed between the Base Station(BS)and Ground Users(GUs). We study the energy-efficiency gap between the link “BS-UAV-GUs”and the link “BS-GUs”, and jointly optimize UAV relay transmission power and flight radius to achieve the highest energy-efficiency. Firstly, the UAV/BS-GUs channels models and the UAV energy consumption model are built. Secondly, the optimization objective function is formulated to maximize the energy-efficiency gap. Then, the solution of the optimization problem is divided into a two-step iteration process, in which the UAV relay transmission power and flight radius are adjusted to maximize the energy-efficiency gap. Finally, the experimental results under different simulation scenarios(such as cities, forests, deserts, oceans, etc.) are shown to illustrate the effectiveness of the proposed algorithm. The results show that the proposed algorithm can always find the optimal UAV relay transmission power and flight radius settings, and achieve the largest energy-efficiency gap. The convergency speed of the proposed algorithm is fast, and can obtain the optimal solution within only a few iterations. 展开更多
关键词 Circular trajectory Energy efficiency fixed wing UAV Power allocation UAV relay
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