共查询到20条相似文献，搜索用时 453 毫秒
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在介绍数字化安防综合监控系统的功能和特点的基础上,着重阐述了中南大学医学图书馆新馆安防综合监控系统的实施情况。 相似文献
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在分析目前现有安防系统存在问题的基础上,提出了分布式光纤监控预警系统与视频、红外等安防监控系统的联动解决方案。就系统结构、传感光缆敷设方式、监控中心的设计等问题进行了详细的阐述,分析了分布式光纤监控预警系统的特点。 相似文献
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机场安防系统主要由安检系统、视频监控系统、门禁系统(或称出入口控制系统)、防盗报警系统、周界电子防范系统、火灾报警系统、巡更系统和公共广播系统等几部分组成.本文通过对国內某权场通道门安防系统的设计分析,阐述了通道门安防系统在机场中安全管理中的重要作用;并对相关子系统的结构及功能进行了介绍. 相似文献
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雷电对安装在室外的安防监控系统具有重大的威胁,缺少防护措施将导致不堪设想的后果.因此本文从理论上阐述了安防监控系统工程中防雷设计重要性,结合案例示范对安防监控系统从监控机房线路及室外监控摄像机的防雷避雷作了详细的描述. 相似文献
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<正>（一）背景与研究意义随着科技的快速发展和城市化进程的加速,安防监控系统在维护社会治安、保障人民生命财产安全等方面发挥着越来越重要的作用。传统的安防监控系统主要依赖人工监控,存在诸多局限性,如信息传递速度慢、准确性低等。为了克服这些问题,智能安防监控系统应运而生,通过多源数据融合技术,提高监控效率和准确性。 相似文献
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根据厂房安防监控的实际问题,提出现场、前台、后台三层架构的解决方案。在阐述方案总体结构和硬件平台的基础上,设计软件框架,设计实现了信息检索、移动侦测算法、广域网监控等关键技术。实验表明,移动侦测算法比常规的移动侦测算法稳定性好效率高,监控软件成本低、易于维护、运行稳定,具有推广应用价值。 相似文献
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《Journal of The Franklin Institute》2023,360(11):7481-7500
The study aims to solve the problem of real time tracking and precise landing of unmanned aerial vehicle (UAV) during unmanned surface vehicle (USV) navigation. In this paper, a UAV-USV cooperative tracking and landing control strategy based on nonlinear model predictive control (NMPC) is proposed. Firstly, the UAV-USV heterogeneous intelligent body collaborative system is constructed based on the mathematical model of UAV and USV; secondly, the tracking controller is designed based on NMPC algorithm to ensure that the UAV can track the USV in real time; finally, a UAV-USV cooperative landing control strategy is proposed to realize the heave motion of the USV to the peak vertex, thus, the UAV completes the precise landing with the minimum impact. As the simulation experimental results show, the UAV-USV cooperative tracking and landing control scheme proposed in this paper can provide effective solution against real time tracking and accurate landing of UAV during the navigation of USV. 相似文献
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《Journal of The Franklin Institute》2021,358(17):8811-8837
This paper investigates the finite-time cooperative formation control problem for a heterogeneous system consisting of an unmanned ground vehicle (UGV) - the leader and an unmanned aerial vehicle (UAV) - the follower. The UAV system under consideration is subject to modeling uncertainties, external disturbance as well as actuator faults simultaneously, which is associated with aerodynamic and gyroscopic effects, payload mass, and other external forces. First, a backstepping controller is developed to stabilize the leader system to track the desired trajectory. Second, a robust nonsingular fast terminal sliding mode surface is designed for UAV and finite-time position control is achieved using terminal sliding mode technique, which ensures the formation error converges to zero in finite time in the presence of actuator faults and other uncertainties. Furthermore, by combining the radial basis function neural networks (NNs) with adaptive virtual parameter technology, a novel NN-based adaptive nonsingular fast terminal sliding formation controller (NN-ANFTSMFC) is developed. By means of the proposed adaptive control strategy, both uncertainties and actuator faults can be compensated without the prior knowledges of the uncertainty bounds and fault information. By using the proposed control schemes, larger actuator faults can be tolerated while eliminating control chattering. In order to realize fast coordinated formation, the expected position trajectory of UAV is composed of the leader position information and the desired relative distance with UGV, based on local distributed theory, in the three-dimensional space. The tracking and formation controllers are proved to be stable by the Lyapunov theory and the simulation results demonstrate the effectiveness of proposed algorithms. 相似文献
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《Journal of The Franklin Institute》2023,360(3):1953-1977
In this study, a new robust homography-based visual tracking control approach for the quadrotor unmanned aerial vehicle (UAV) is developed. Specifically, employing the homography matrix as feedback, a hierarchical homography-based visual servoing (HBVS) scheme with a new command attitude extraction method to account for the underactuation of UAV is proposed. On this basis, a smooth hyperbolic tangent function is fulfilled as an augmented part of the backstepping control scheme, which guarantees the non-negative total thrust and avoid singularity. Additionally, a cascaded filter-based estimator and adaptive laws with integrable functions are embedded to counteract uncertainties including external perturbations, unknown acceleration of the moving target, and unknown image depth, and to facilitate the system’s asymptotic stability simultaneously. The theoretical analysis testifies that the whole close-loop system is asymptotically stable. Simulations further verify that the proposed HBVS controller can realize the visual tracking with a superior performance. 相似文献
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Yixuan Wang Yan Shi Maolin Cai Weiqing Xu Qihui Yu 《Journal of The Franklin Institute》2018,355(17):8554-8575
Traditional control method of air–fuel ratio (AFR) of aero engine cannot meet the performance requirement of fuel-powered unmanned aerial vehicle (UAV), which may lead to efficiency reduction and emission increase. In order to improve the control accuracy, this paper proposes a new AFR control method based on fuzzy-PID. We analyze the control results under different working conditions by using adaptive fuzzy-PID. Through simulation and experimental studies, we can draw the conclusions as follows: compared with PID control method, firstly, AFR control error can be reduced by 80% in normal condition; secondly, the control error is reduced by 55% in rapid acceleration condition; in addition, the control error can be reduced by 71% in continuous disturbance condition; comparison results with existing Fuzzy-PID also show that the improved controller has advantage in terms of resisting rapid and continuous interferences; moreover, in practical application of fuzzy-PID control, the highest AFR errors are about 3%. In normal condition, the error is reduced from 5 to 1% compared with PID control, which demonstrates the effectiveness of the improved fuzzy-PID control model. This research can be a reference in the application of UAV aero engine control. 相似文献
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A fault tolerant control scheme for actuator and sensor faults is proposed for a tilt-rotor unmanned aerial vehicle (UAV) system. The tilt-rotor UAV has a vertically take-off and landing (VTOL) capability like a helicopter during the take-off & landing while it could cruise with a high speed as a conventional airplane flight mode. A dual system in the flight control computer (FCC) and the sensor is proposed in this study. To achieve a high reliability, a fault tolerant flight control system is required for the case of actuator or sensor fault. For the actuator fault, the fault tolerant control scheme based on model error control synthesis is presented. A designed fault tolerant control scheme does not require system identification process and it provides an effective reconfigurability without fault detection and isolation (FDI) process. For the sensor fault, the fault tolerant federated Kalman filter is designed for the tilt-rotor UAV system. An FDI algorithm is applied to the federated Kalman filter in order to improve the accuracy of the state estimation even when the sensor fails. For a linearized six-degree-of-freedom linear model and nonlinear model of the tilt-rotor UAV, numerical simulation and process-in-the-loop simulation (PILS) are performed to demonstrate the performance of the proposed fault tolerant control scheme. 相似文献
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Gabriele Perozzi Denis Efimov Jean-Marc Biannic Laurent Planckaert 《Journal of The Franklin Institute》2018,355(12):4809-4838
The problem of position tracking of a mini drone subject to wind perturbations is investigated. The solution is based on a detailed unmanned aerial vehicle (UAV) model, with aerodynamic coefficients and external disturbance components, which is introduced in order to better represent the impact of the wind field. Then, upper bounds of wind-induced disturbances are characterized, which allow a sliding mode control (SMC) technique to be applied with guaranteed convergence properties. The peculiarity of the considered case is that the disturbance upper bounds depend on the control amplitude itself (i.e. the system is nonlinear in control), which leads to a new procedure for the control tuning presented in the paper. The last part of the paper is dedicated to the analysis and reduction of chattering effects, as well as investigation of rotor dynamics issues. Conventional SMC with constant gains, proposed first order SMC, and proposed quasi-continuous SMC are compared. Nonlinear UAV simulator, validated through in-door experiments, is used to demonstrate the effectiveness of the proposed controls. 相似文献
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无人机产业发展关系我国国防军工核心能力建设以及数字化低空产业经济的构建。随着国家军民融合深度发展战略的布局,我国无人机产业呈现出爆炸式增长趋势。无人机产业的深度发展与其军民融合水平评价体系建设紧密相关。目前学术界对于军民融合水平评价研究还只停留在宏观层面。本文基于扎根理论和模糊层次分析方法,构建了一种从微观视角开展无人机产业军民融合深度发展研究的理论方法。首先进行无人机产业军民融合问题的数据采集、数据编码和饱和度校验,确定融合水平影响要素的理论模型,然后将影响要素的选择性编码和主轴编码分别作为4个一级指标因素和15个二级指标因素输入,基于德尔菲方法和层次分析法,进行因素输入的权重确定和融合水平的评估。最后文中完成了3家国有无人机企业军民融合水平的实证分析,针对分析结果,提出了军民融合深度发展建设意见。本文提出的理论分析方法也可拓展应用于国家相关主管部门及其它产业。 相似文献
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This study focuses on a sampled-data fuzzy decentralized tracking control problem for a quadrotor unmanned aerial vehicle (UAV) under the variable sampling rate condition. To this end, the overall dynamics of the quadrotor is expressed as a decentralized Takagi–Sugeno (T–S) fuzzy model interconnected with each other. Although the proposed decentralized control technique divides the overall UAV control system into attitude and position subsystems, the stability of the entire control system is guaranteed. Besides, in this paper, the model uncertainty, interconnection, and reference trajectory are considered as disturbances acting on the tracking error. To attenuate these disturbances, a novel sampled-data tracking control design technique is derived based on a linear reference model to be tracked and the time-dependent Lyapunov–Krasovskii functional (LKF). By doing so, both the stability of the tracking error dynamics and the minimization of tracking performance are guaranteed. Also, the proposed tracking control design method is derived as a linear matrix inequality (LMI)-based optimal problem. Finally, a simulation example is provided to demonstrate the effectiveness and feasibility of the proposed design methodology. 相似文献
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For the purpose of fault detection and isolation (FDI), reconstruction-based contribution (RBC) analysis is carried out in a model-based way. A bank of adaptive observers are designed for a set of potential faults. From these observers, fault estimates and fault signatures are directly available, thus contribution functions are conveniently constructed to accomplish the FDI work. This integrated design of contribution analysis and adaptive observer takes advantages of both data-driven and model-based approaches, and the diagnosis performance is improved. Furthermore, quantitative isolability analysis is also studied by similarity measurement of the obtained fault signatures. Simulation study with a nonlinear unmanned aerial vehicle (UAV) model shows the effectiveness of the proposed method. 相似文献