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Modeling novel methodologies for unmanned aerial systems–Applications to the UAS-S4 Ehecatl and the UAS-S45 Bálaam

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Chinese Journal of Aeronautics 2019年第1期32卷 58-77页

作者： Maxime Alex Junior KUITCHE Ruxandra Mihaela BOTEZ ETS Laboratory of Active ControlsAvionics and AeroServoElasticity LARCASE

The rising demand for unmanned Aerial Systems(UASs) to perform tasks in hostile environments has emphasized the need for their simulation models for the preliminary evaluations of their missions. The efficiency of the UAS model is directly related to its capacity to estimate its flight dynamics with minimum computational resources. The literature describes several techniques to estimate accurate aircraft flight dynamics. Most of them are based on system identification. This paper presents an alternative methodology to obtain complete model of the S4 and S45 unmanned aerial systems. The UAS-S4 and the UAS-S45 models were divided into four sub-models, each corresponding to a specific discipline: aerodynamics, propulsion, mass and inertia, and actuator. The‘‘aerodynamic" sub-model was built using the Fderivatives in-house code, which is an improvement of the classical DATCOM procedure. The ‘‘propulsion" sub-model was obtained by coupling a two-stroke engine model based on the ideal Otto cycle and a Blade Element Theory(BET) analysis of the propeller. The ‘‘mass and the inertia" sub-model was designed utilizing the Raymer and DATCOM methodologies. A sub-model of an actuator using servomotor characteristics was employed to complete the model. The total model was then checked by validation of each submodel with numerical and experimental data. The results indicate that the obtained model was accurate and could be used to design a flight simulator.

关键词： Aerodynamics Aerospace propulsion Flight dynamics unmanned aerial vehicles modeling

A novel gradient climbing control for seeking the best communication point for data collection from a seabed platform using a single unmanned surface vehicle

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Frontiers of Information Technology & Electronic Engineering 2019年第6期20卷 751-759页

作者： Jiu-cai JIN Jie ZHANG Zhi-chao LV First Institute of Oceanography Ministry of Natural Resources Qingdao 266061 China College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

A novel controller for finding the best communication point is proposed for collecting data from a seabed platform by a single unmanned surface vehicle(USV) using underwater acoustic communication(UAC). As far as we know, extremum seeking based on climbing control is usually implemented by multiple vehicles or agents because of the large range of measurement and easy acquisition of gradient estimation. A single vehicle cannot rapidly estimate the field because of the limited extent for measurement;therefore, it is difficult for a single vehicle to seek the extremum point in a field. In this study, an oscillation motion(OM) is designed for a single USV to acquire UAC’s link strength data between the seabed platform and the USV. The field for UAC’s link strength is updated using new measurement from an OM of the USV based on a multi-variable weight linear iteration method. A controller for seeking the best UAC’s point of the USV is designed using gradient climbing and artificial potential considering iterative estimation of an unknown field and an OM operation, and the stability is proved. The reliability and efficiency are shown in simulation results.

关键词： unmanned surface vehicle Data collection Underwater acoustic communication Gradient climbing Extremum seeking

Robust adaptive compensation control for unmanned autonomous helicopter with input saturation and actuator faults

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Chinese Journal of Aeronautics 2019年第10期32卷 2299-2310页

作者： Kun YAN Mou CHEN Qingxian WU Ronggang ZHU College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Luoyang Institute of Electro-Optical Equipment of AVIC Luoyang 471000China

This paper studies a robust adaptive compensation Fault Tolerant Control(FTC)for the medium-scale unmanned Autonomous Helicopter(UAH)in the presence of external disturbances,actuator faults and input *** improve the disturbance rejection capacity of the UAH system in actuator healthy case,an adaptive control method is adopted to cope with the external disturbances and a nominal controller is proposed to stabilize the ***,compensation control inputs are designed to reduce the negative effects derived from actuator faults and input *** on the backstepping control and inner-outer loop control technologies,a robust adaptive FTC scheme is developed to guarantee the tracking errors *** the presented FTC controller,the uniform ultimate boundedness of all closed-loop signals is ensured via Lyapunov stability *** results demonstrate the effectiveness of the proposed control algorithm.

关键词： Compensation control Fault tolerant control Input saturation Tracking control unmanned autonomous helicopter

Placement of unmanned aerial vehicles as communication relays in two-tiered multi-agent system:clustering based methods

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Journal of Systems Engineering and Electronics 2020年第2期31卷 231-242页

作者： WU Gaofeng WAN Kaifang GAO Xiaoguang FU Xiaowei School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

The network performance and the unmanned aerial vehicle(UAV)number are important objectives when UAVs are placed as communication relays to enhance the multi-agent information *** problem is a non-deterministic polynomial hard(NP-hard)multi-objective optimization problem,instead of generating a Pareto solution,this work focuses on considering both objectives at the same level so as to achieve a balanced solution between *** on the property that agents connected to the same UAV are a cluster,two clustering-based algorithms,M-K-means(MKM)and modified fast search and find density of peaks(MFSFDP)methods,are first *** the former algorithm requires too much computational time and the latter one requires too many relays,an algorithm for the balanced network performance and relay number(BPN)is proposed by discretizing the area to avoid missing the optimal relay positions and defining a new local density function to reflect the network performance *** results demonstrate that the proposed algorithms are feasible and *** between these algorithms show that the BPN algorithm uses fewer relay UAVs than the MFSFDP and classic set-covering based algorithm,and its computational time is far less than the MKM algorithm.

关键词： unmanned aerial vehicle(UAV) relay communication clustering relay node placement wireless network

Real-time object tracking via least squares transformation in spatial and Fourier domains for unmanned aerial vehicles

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Chinese Journal of Aeronautics 2019年第7期32卷 1716-1726页

作者： Xiaoyuan YANG Ridong ZHU Jingkai WANG Zhengze LI School of Mathematics and Systems Science Beihang University

This paper addresses the problem of real-time object tracking for unmanned aerial vehicles. We consider the task of object tracking as a classification problem. Training a good classifier always needs a huge number of samples, which is always time-consuming and not suitable for realtime applications. In this paper, we transform the large-scale least-squares problem in the spatial domain to a series of small-scale least-squares problems with constraints in the Fourier domain using the correlation filter technique. Then, this problem is efficiently solved by two stages. In the first stage, a fast method based on recursive least squares is used to solve the correlation filter problem without constraints in the Fourier domain. In the second stage, a weight matrix is constructed to prune the solution attained in the first stage to approach the constraints in the spatial domain. Then, the pruned classifier is used for tracking. To evaluate proposed tracker’s performance, comprehensive experiments are conducted on challenging aerial sequences in the UAV123 dataset. Experimental results demonstrate that proposed approach achieves a state-ofthe-art tracking performance in aerial sequences and operates at a mean speed of beyond 40 frames/s. For further analysis of proposed tracker’s robustness, extensive experiments are also performed on recent benchmarks OTB50, OTB100, and VOT2016.

关键词： Correlation filter Discrete Fourier transform Least squares Object tracking unmanned aerial vehicle

Mobility control of unmanned aerial vehicle as communication relay in airborne multi-user systems

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中国航空学报：英文版 2019年第6期32卷 1520-1529页

作者： Gaofeng WU Xiaoguang GAO Xiaowei Fu Kaifang WAN Ruohai DI School of Electronics and Information Northwestern Polytechnical University

In this paper, a model-based adaptive mobility control method for an unmanned Aerial Vehicle(UAV) acting as a communication relay is presented, which is intended to improve the network performance in airborne multi-user systems. The mobility control problem is addressed by jointly considering unknown Radio Frequency(RF) channel parameters, unknown multi-user mobility, and non-available Angle of Arrival(AoA) information of the received signal. A Kalman filter and a least-square-based estimation algorithm are used to predict the future user positions and estimate the RF channel parameters between the users and the UAV, respectively. Two different relay application cases are considered: end-to-end and multi-user communications. A line search algorithm is proposed for the former, with its stability given and proven, whereas a simplified gradient-based algorithm is proposed for the latter to provide a target relay position at each decision time step, decreasing the two-dimensional search to a one-dimensional search. Simulation results show that the proposed mobility control algorithms can drive the UAV to reach or track the optimal relay position movement, as well as improving network performance. The proposed method reflects the properties of using different metrics as objective network performance functions.

关键词： Channel estimation Gradient methods Motion control Optimization Relay unmanned aerial vehicle Wireless networks

Bottom-following control for an underactuated unmanned undersea vehicle using integral-terminal sliding mode control

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中南大学学报：英文版 2015年第11期22卷 4193-4204页

作者：严浙平于浩淼李本银 College of Automation Harbin Engineering University

The bottom-following problem of an underactuated unmanned undersea vehicle(UUV) is addressed. A robust nonlinear controller is developed by using integral-terminal sliding mode control(ITSMC), which can exponentially drive an UUV onto a predefined path at a constant forward speed. The kinematic error equations are first derived in the Serret-Frenet frame. Using the line of sight(LOS) method, Lyapunov's direct technique and tracking differentiator, the guidance law is established. Then, the kinematic controller, the guidance law, is expanded to cope with vehicle dynamics by resorting to introduce two integral-terminal sliding surfaces. Robustness to parameter perturbation is addressed by incorporating the reaching laws associated with the upper bound of the parameter perturbation. The proposed control law can guarantee that all error signals globally exponentially converge to the origin. Finally, a series of numerical simulation results are presented and discussed. In these simulations, wave, constant unknown ocean currents(for the purposes of the controller) and the parameter perturbation are added to illustrate the robustness and effectiveness of the bottom-following control scheme.

关键词： underactuated unmanned undersea vehicle integral-t

A Multi-Point Distance-Bounding Protocol for Securing Automatic Dependent Surveillance-Broadcast in unmanned Aerial Vehicle Applications

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Journal of Computer Science & Technology 2020年第4期35卷 825-842页

作者： Zachary P.Languell Qijun Gu Department of Computer Science Texas State UniversitySan MarcosTX 78666USA

The Automatic Dependent Surveillance-Broadcast(ADS-B)protocol is being adopted for use in unmanned aerial vehicles(UAVs)as the primary source of information for emerging multi-UAV collision avoidance *** lack of security features in ADS-B leaves any processes dependent upon the information vulnerable to a variety of threats from compromised and dishonest *** could result in substantial losses or damage to *** research proposes a new distance-bounding scheme for verifying the distance and flight trajectory in the ADS-B broadcast data from surrounding *** proposed scheme enables UAVs or ground stations to identify fraudulent UAVs and avoid *** scheme was implemented and tested in the ArduPilot SITL(Software In The Loop)simulator to verify its ability to detect fraudulent *** experiments showed that the scheme achieved the desired accuracy in both flight trajectory measurement and attack detection.

关键词： automatic dependent surveillance-broadcast (ADS-B) unmanned aerial vehicle (UAV) distance bounding collision airspace safety

FBCRI Based Real-time Path Planning for unmanned Aerial Vehicles in Unknown Environments with Uncertainty

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机器人 2013年第6期35卷 641-650页

作者： LIU Wei HAO Peng ZHENG Zheng CAI Kaiyuan School of Automation Science and Electrical Engineering Beihang University Science and Technology on Aircraft Control Laboratory High-Tech Institute of Xi'an

This paper presents an FBCRI(feedback based compositional rule of inference)based novel path planning method to satisfy the requirements of real-time navigation,smoothness optimization and probabilistic obstacle *** local path-searching behaviors in regional ranges and global goal-seeking behaviors in holistic ranges,the method infers behavior weights using fuzzy reasoning embedded with feedback,and then coordinates the behaviors to generate new reference *** view of the deterministic decisions and the uncertain states of a UAV(unmanned air vehicle),chance constraints are adopted to probabilistically guarantee the UAV’s safety at a required *** results in representative scenes prove that the method is able to rapidly generate convergent paths in obstacle-rich environments,as well as highly improve the path quality with respect to smoothness and probabilistic safety.

关键词： unmanned aerial vehicle path planning fuzzy reasoning FBCRI(feedback based compositional rule of inference) uncertainty