Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Fixed-wing UAV guidance.
Artykuły w czasopismach na temat „Fixed-wing UAV guidance”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 43 najlepszych artykułów w czasopismach naukowych na temat „Fixed-wing UAV guidance”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.
1
Israr, Amber, Eman H. Alkhammash i Myriam Hadjouni. "Guidance, Navigation, and Control for Fixed-Wing UAV". Mathematical Problems in Engineering 2021 (16.10.2021): 1–18. http://dx.doi.org/10.1155/2021/4355253.
Pełny tekst źródłaStreszczenie:
The purpose of this paper is to develop a fixed-wing aircraft that has the abilities of both vertical take-off (VTOL) and a fixed-wing aircraft. To achieve this goal, a prototype of a fixed-wing gyroplane with two propellers is developed and a rotor can maneuver like a drone and also has the ability of vertical take-off and landing similar to a helicopter. This study provides guidance, navigation, and control algorithm for the gyrocopter. Firstly, this study describes the dynamics of the fixed-wing aircraft and its control inputs, i.e., throttle, blade pitch, and thrust vectors. Secondly, the inflow velocity, the forces acting on the rotor blade, and the factors affecting the rotor speed are analyzed. Afterward, the mathematical models of the rotor, dual engines, wings, and vertical and horizontal tails are presented. Later, the flight control strategy using a global processing system (GPS) module is designed. The parameters that are examined are attitude, speed, altitude, turn, and take-off control. Lastly, hardware in the loop (HWIL) based simulations proves the effectiveness and robustness of the navigation guidance and control mechanism. The simulations confirm that the proposed novel mechanism is robust and satisfies mission requirements. The gyrocopter remains stable during the whole flight and maneuvers the designated path efficiently.
2
Zhai, Rui Yong, Wen Dong Zhang, Zhao Ying Zhou, Sheng Bo Sang i Pei Wei Li. "Trajectory Tracking Control for Micro Unmanned Aerial Vehicles". Advanced Materials Research 798-799 (wrzesień 2013): 448–51. http://dx.doi.org/10.4028/www.scientific.net/amr.798-799.448.
Pełny tekst źródłaStreszczenie:
This article considers the problem of trajectory tracking control for a micro fixed-wing unmanned air vehicle (UAV). With Bank-to-Turn (BTT) method to manage lateral deviation control of UAV, this paper discusses the outer loop guidance system, which separates the vehicle guidance problems into lateral control loop and longitudinal control loop. Based on the kinematic model of the coordinated turning of UAV, the aircraft can track a pre-specified flight path with desired error range. Flight test results on a fixed-wing UAV have indicated that the trajectory tracking control law is quite effective.
3
Wang, Shuo, Ziyang Zhen, Ju Jiang i Xinhua Wang. "Flight Tests of Autopilot Integrated with Fault-Tolerant Control of a Small Fixed-Wing UAV". Mathematical Problems in Engineering 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/2141482.
Pełny tekst źródłaStreszczenie:
A fault-tolerant control scheme for the autopilot of the small fixed-wing UAV is designed and tested by the actual flight experiments. The small fixed-wing UAV called Xiang Fei is developed independently by Nanjing University of Aeronautics and Astronautics. The flight control system is designed based on an open-source autopilot (Pixhawk). Real-time kinematic (RTK) GPS is introduced due to its high accuracy. Some modifications on the longitudinal and lateral guidance laws are achieved to improve the flight control performance. Moreover, a data fusion based fault-tolerant control scheme is integrated in altitude control and speed control for altitude sensor failure and airspeed sensor failure, which are the common problems for small fixed-wing UAV. Finally, the real flight experiments are implemented to test the fault-tolerant control based autopilot of UAV. Real flight test results are given and analyzed in detail, which show that the fixed-wing UAV can track the desired altitude and speed commands during the whole flight process including takeoff, climbing, cruising, gliding, landing, and wave-off by the fault-tolerant control based autopilot.
4
Iong, P. T., S. H. Chen i Y. Yang. "Vision guidance of a fixed wing UAV using a single camera configuration". Aeronautical Journal 117, nr 1188 (luty 2013): 147–73. http://dx.doi.org/10.1017/s0001924000007922.
Pełny tekst źródłaStreszczenie:
Abstract In this paper a single camera vision guidance system for fixed wing UAV is developed. This system searches for and identifies a target object with known colour and shape from images captured by an onboard camera. HSV colour space and moment invariants are utilised to describe the colour and shape features of the target object. Position, area and rotation angle of the target object in the image plane are collected. This information is then processed by the Extended Kalman Filter to estimate the relative positions and attitudes of the UAV. The vision guidance system guides the UAV towards the target object automatically based on these estimated states by using a proportional controller. A Senior Telemaster aircraft model kit installed with an onboard camera and computer is used for flight test. The target object for the flight test is a white flag with a red cross. Flight simulations and flight tests results are presented in this paper, showing that the vision guidance system can recognise the target object and guide the UAV effectively.
5
Xiong, Wei, Zhao Ying Zhou i Xiao Yan Liu. "Study of Low Cost Micro Autopilot for Fixed-Wing UAV". Advanced Materials Research 317-319 (sierpień 2011): 1672–76. http://dx.doi.org/10.4028/www.scientific.net/amr.317-319.1672.
Pełny tekst źródłaStreszczenie:
From the cost-effective viewpoint of low cost Bank-to-Turn (BTT) Unmanned Air Vehicles (UAV) and target drone, a low cost flight control system, with the fewest number of sensors, is studied in this paper for the fixed-wing UAV. The structure of the control system is described which is able to estimate necessary information to provide stabilization and guidance for a small fixed wing BTT UAV. The practical flight control system structure and control law for roll hold loop, altitude hold loop, trajectory tracking loop are designed based on the sensor configuration with only a MEMS rate gyro, a MEMS pressure sensor and global positioning system (GPS) receiver only. A prototype low cost autopilot is trial-produced to control a typical UAV. The Experimental results show the effectiveness of navigation and control methods of f the proposed methodology.
6
Lee, C.-S., i F.-B. Hsiao. "Implementation of vision-based automatic guidance system on a fixed-wing unmanned aerial vehicle". Aeronautical Journal 116, nr 1183 (wrzesień 2012): 895–914. http://dx.doi.org/10.1017/s000192400000734x.
Pełny tekst źródłaStreszczenie:
Abstract This paper presents the design and implementation of a vision-based automatic guidance system on a fixed-wing unmanned aerial vehicle (UAV). The system utilises a low-cost ordinary video camera and simple but efficient image processing techniques widely used in computer-vision technology. The paper focuses on the identification and extraction of geographical tracks such as rivers, coastlines, and roads from real-time aerial images. The image processing algorithm primarily uses colour properties to isolate the geographical track of interest from its background. Hough transform is eventually used to curve-fit the profile of the track which yields a reference line on the image plane. A guidance algorithm is then derived based on this information. In order to test the vision-based automatic guidance system in the laboratory without actually flying the UAV, a hardware-in-the-loop simulation system is developed. Description regarding the system and significant simulation result are presented in the paper. Finally, an actual test flight where the UAV successfully follows a stretch of a river under automatic vision-based guidance is also presented and discussed.
7
Deng, Zhao, Zhiming Guo, Liaoni Wu i Yancheng You. "Trajectory Planning for Emergency Landing of VTOL Fixed-Wing Unmanned Aerial Vehicles". Mobile Information Systems 2021 (29.11.2021): 1–15. http://dx.doi.org/10.1155/2021/6289822.
Pełny tekst źródłaStreszczenie:
In recent years, inspired by technological progress and the outstanding performance of Unmanned Aerial Vehicles (UAVs) in several local wars, the UAV industry has witnessed explosive development, widely used in communication relay, logistics, surveying and mapping, patrol, surveillance, and other fields. Vertical Take-Off and Landing fixed-wing UAV has both the advantages of vertical take-off and landing of rotorcraft and the advantages of long endurance of fixed-wing UAV, which broadened its application field and is the most popular UAV at present. Recently, fixed-wing UAV failure analysis highlights that cruise engine shutdown is the most common reason for emergency landing, which is also a governing factor for Vertical Take-Off and Landing (VTOL) fixed-wing UAV failures. Nevertheless, the emergency landing trajectory of the latter UAV type after engine shutdown is different from that of the conventional fixed-wing UAVs due to the VTOL power system. Hence, spurred by the requirement of a safe emergency landing trajectory for VTOL fixed-wing UAVs, this paper develops an architecture capable of safe emergency landing for such platforms. The suggested method develops a particle dynamics model of the VTOL UAV and analyzes its aerodynamic characteristics utilizing Computational Fluid Dynamics (CFD) results. The UAV’s trajectory is divided into three parts for enhanced planning. For the guidance stage, the initial position and heading angle are arbitrary. Hence, the Dubins shortest cross-range and the fastest descent trajectory are adopted to steer the UAV above the landing window quickly. The spiral stage comprises a conical and cylindrical part combined with a spiral descent trajectory of variable radius for energy management and landing course alignment. Given the limited energy storage of VTOL power systems, the landing stage exploits an optimal control trajectory problem solved by a Gaussian pseudospectral method, involving trajectory conventional landing planning, unpowered landing, distance optimal landing, and wind-resistant landing. All trajectories meet the dynamics constraints, terminal constraints, and sliding performance constraints and cover both 2-dimensional and 3-dimensional trajectories. A large number of simulation experiments demonstrate that the proposed trajectories manage broad applicability and strong feasibility for VTOL fixed-wing UAVs.
8
Chen, Chao, i Jiali Tan. "Path Following for UAV using Nonlinear Model Predictive Control". Journal of Physics: Conference Series 2530, nr 1 (1.06.2023): 012021. http://dx.doi.org/10.1088/1742-6596/2530/1/012021.
Pełny tekst źródłaStreszczenie:
Abstract For the fixed-wing UAV control system, the lateral path-following system is an important part, which ensures that the UAV flies stably in accordance with the predetermined route within a certain height. For the lateral path following of UAV based on nonlinear model predictive control, the model of the lateral kinematics of the fixed-wing UAV is established first, and then the path-following problem of UAV at a constant height is considered. The objective function with constraints based on the NMPC is established, and finally the nonlinear optimization algorithm is used to minimize the designed objective function. The optimal control quantity in the rolling interval is obtained. Matlab is used to simulate the designed controller and compare it with the commonly used L1 guidance law, and the results of the simulation demonstrate that the NMPC has superior control leverage.
9
Mat, Amir Rasydan, Liew Mun How, Omar Kassim Ariff, M. Amzari M. Zhahir i Ramly Mohd Ajir. "Autonomous Aerial Hard Docking of Fixed and Rotary Wing UAVs: Task Assessment and Solution Architecture". Applied Mechanics and Materials 629 (październik 2014): 176–81. http://dx.doi.org/10.4028/www.scientific.net/amm.629.176.
Pełny tekst źródłaStreszczenie:
This paper covers exploratory efforts that attempt to address limitations and restrictions in the operating envelope of UAVs, and proposes a conceptual solution to the problem. UAVs, like aircraft, can be categorized into two main types: fixed wing and rotary wing. A fixed wing UAV flies using wings that generate lift caused by the vehicle’s forward airspeed and the shape of the wings. The greatest advantage of fixed wing UAVs obtained from utilizing aerodynamic lift is its long range and high endurance performance. However, this primary advantage comes from the fact that most fixed wing UAVs have wings that are of a high aspect ratio, which becomes a liability in confined operating conditions. An autonomous aerial hard docking system is proposed as a system that manages to enable different UAV platforms to have operational envelopes which far exceed the operational envelopes of the constituent UAV platforms. The paper outlines necessary subsystems that need to exist for autonomous aerial hard docking capability. It presents practical requirements of the various constituent subsystems, namely the guidance and navigation subsystem, the grasping subsystem and the damping subsystem. For each of the subsystems, the challenges which have to be overcome to ensure the effectiveness of the complete system are examined. It further elaborates the testing, investigation and development steps that need to be implemented to realize this capability. It ends by elaborating on the work already underway and future development plans. Note that this paper presents a conceptual logical and architectural solution, and as such detailed analysis findings are inappropriate and premature.
10
Lee, Jehoon, i Sanghyuk Park. "Pre-simulation based Automatic Landing Approach by Waypoint Guidance for Fixed-Wing UAV". Journal of the Korean Society for Aeronautical & Space Sciences 49, nr 7 (31.07.2021): 557–64. http://dx.doi.org/10.5139/jksas.2021.49.7.557.
Pełny tekst źródła
11
Gong, Zheng, Zan Zhou, Zian Wang, Quanhui Lv, Jinfa Xu i Yunpeng Jiang. "Coordinated Formation Guidance Law for Fixed-Wing UAVs Based on Missile Parallel Approach Method". Aerospace 9, nr 5 (18.05.2022): 272. http://dx.doi.org/10.3390/aerospace9050272.
Pełny tekst źródłaStreszczenie:
This paper presents a classic missile-type parallel-approach guidance law for fixed-wing UAVs in coordinated formation flight. The key idea of the proposed guidance law is to drive each follower to follow the virtual target point. Considering the turning ability of each follower, the formation form adopts the semi-perfect rigid form, which does not require the vehicle positions form a rigid formation, and the orientations keep consensus. According to the mission characteristics of the follower following a leader and the leader following a route, three guidance laws for straight, turning, and circling flight are designed. A series of experiments demonstrate the proposed guidance law’s improved response and maneuvering stability. The results of hardware-in-the-loop simulations and real flight tests prove that the proposed guidance law satisfies the practical UAV formation flight control demands.
12
Yang, Jun, Arun Geo Thomas, Satish Singh, Simone Baldi i Ximan Wang. "A Semi-Physical Platform for Guidance and Formations of Fixed-Wing Unmanned Aerial Vehicles". Sensors 20, nr 4 (19.02.2020): 1136. http://dx.doi.org/10.3390/s20041136.
Pełny tekst źródłaStreszczenie:
Unmanned Aerial Vehicles (UAVs) have multi-domain applications, fixed-wing UAVs being a widely used class. Despite the ongoing research on the topics of guidance and formation control of fixed-wing UAVs, little progress is known on implementation of semi-physical validation platforms (software-in-the-loop or hardware-in-the-loop) for such complex autonomous systems. A semi-physical simulation platform should capture not only the physical aspects of UAV dynamics, but also the cybernetics aspects such as the autopilot and the communication layers connecting the different components. Such a cyber-physical integration would allow validation of guidance and formation control algorithms in the presence of uncertainties, unmodelled dynamics, low-level control loops, communication protocols and unreliable communication: These aspects are often neglected in the design of guidance and formation control laws for fixed-wing UAVs. This paper describes the development of a semi-physical platform for multi-fixed wing UAVs where all the aforementioned points are carefully integrated. The environment adopts Raspberry Pi’s programmed in C++, which can be interfaced to standard autopilots (PX4) as a companion computer. Simulations are done in a distributed setting with a server program designed for the purpose of routing data between nodes, handling the user inputs and configurations of the UAVs. Gazebo-ROS is used as a 3D visualization tool.
13
Zhan, Guang, Zheng Gong, Quanhui Lv, Zan Zhou, Zian Wang, Zhen Yang i Deyun Zhou. "Flight Test of Autonomous Formation Management for Multiple Fixed-Wing UAVs Based on Missile Parallel Method". Drones 6, nr 5 (19.04.2022): 99. http://dx.doi.org/10.3390/drones6050099.
Pełny tekst źródłaStreszczenie:
This paper reports on the formation and transformation of multiple fixed-wing unmanned aerial vehicles (UAVs) in three-dimensional space. A cooperative guidance law based on the classic missile-type parallel-approach method is designed for the multi-UAV formation control problem. Additionally, formation transformation strategies for multi-UAV autonomous assembly, disbandment, and special circumstances are formed, effective for managing and controlling the formation. When formulating the management strategy for formation establishment, its process is divided into three steps: (i) selecting and allocating target points, (ii) forming loose formations, and (iii) forming short-range formations. The management of disbanding the formation is formulated through reverse thinking: the assembly process is split and recombined in reverse, and a formation disbanding strategy that can achieve a smooth transition from close to lose formation is proposed. Additionally, a strategy is given for adjusting the formation transformation in special cases, and the formation adjustment is completed using the adjacency matrix. Finally, a hardware-in-the-loop simulation and measured flight verification using a simulator show the practicality of the guidance law in meeting the control requirements of UAV formation flight for specific flight tasks.
14
Ángeles-Rojas, David, Omar-Jacobo Santos-Sánchez, Sergio Salazar i Rogelio Lozano. "Finite Horizon Nonlinear Suboptimal Control for an Autonomous Soaring UAV". Mathematical Problems in Engineering 2022 (12.03.2022): 1–15. http://dx.doi.org/10.1155/2022/2214217.
Pełny tekst źródłaStreszczenie:
In this paper, a suboptimal nonlinear discrete control for nonlinear discrete affine systems is implemented in an autonomous soaring unmanned aerial vehicle (UAV) to improve energy consumption and performance. General expressions for this controller are obtained from the continuous nonlinear guidance model of a fixed-wing UAV and applied in a multiloop control structure. Simulation results in the task of trajectory tracking inside a thermal updraft and a comparative study with a proportional derivative (PD) controller validated the effectiveness of this method.
15
Kim, Myungkang, Chunggil Ra, Seungkeun Kim i Jinyoung Suk. "Guidance and Control Algorithm Design for Terrain-Following Flight of a Fixed-Wing UAV". Journal of the Korean Society for Aeronautical & Space Sciences 51, nr 5 (31.05.2023): 299–306. http://dx.doi.org/10.5139/jksas.2023.51.5.299.
Pełny tekst źródła
16
Xi, Yong-Zai, Gui-Xiang Liao, Ning Lu, Yong-Bo Li i Shan Wu. "Study on the Aeromagnetic System between Fixed-Wing UAV and Unmanned Helicopter". Minerals 13, nr 5 (20.05.2023): 700. http://dx.doi.org/10.3390/min13050700.
Pełny tekst źródłaStreszczenie:
Based on the CH-3 and WH-110A unmanned aerial vehicle (UAV) platforms, we independently developed aeromagnetic systems for fixed-wing UAVs (FUAV) and modified unmanned helicopters (MUH), respectively. These systems overcome key technological challenges in system integration, aeromagnetic compensation, and electromagnetic (EM) compatibility. We conducted a 1:100,000 aeromagnetic test using both systems in a tidal flat area in Jiangsu province, China. Both systems successfully completed 240 line km measurement lines and collected high-quality data with magnetic compensation accuracies of 0.01428 nT and 0.04690 nT, respectively. The dynamic noise was below 0.14 nT, accounting for 95.72% and 100% of the measurements. These results indicate that both systems offer high measurement accuracy, efficiency, low cost, convenience, and flexibility. We compared the two aeromagnetic systems based on their system parameters, integration modes, magnetic compensation methods and effects, and practical applications. By comprehensively analyzing their characteristics and application fields, we provide guidance for UAV-based aeromagnetic surveys in mineral exploration, basic geological survey and other related fields. And the FUAV and MUH aeromagnetic systems presented in this paper serve as a valuable reference for future research in this area.
17
Chen, Yang, Nan Li, Wei Zeng i Yongliang Wu. "Curved Path Following Control for a Small Fixed-Wing UAV with Parameters Adaptation". Applied Sciences 12, nr 9 (21.04.2022): 4187. http://dx.doi.org/10.3390/app12094187.
Pełny tekst źródłaStreszczenie:
This paper presents an approach to address the curved-path following problem of a fixed-wing UAV, which can reach uniform optimal path-following performance for different initial states and control processes. First, a proper guidance law is designed following a class of horizontal smooth paths with fixed control parameters. The stability of the relative nonlinear system is guaranteed by the Lyapunov stability theory. The influence of the control parameters on path-following performance has been analyzed. Second, the rules of the time-varying control parameters are designed separately. The rules of the time-varying P-like parameter are designed by analyzing the dynamic characteristics of the nonlinear system with different initial flight states. The rules of the time-varying D-like parameter are designed based on the fuzzy logic technique. The stability of the corresponding nonautonomous nonlinear system is also proved. The simulations are carried out in the Matlab/Simulink environment with an Aerosonde UAV model. The results are presented to illustrate the effectiveness and high path-following performances of the proposed control strategies.
18
Muslimov, Tagir Z., i Rustem A. Munasypov. "Multi-UAV cooperative target tracking via consensus-based guidance vector fields and fuzzy MRAC". Aircraft Engineering and Aerospace Technology 93, nr 7 (7.08.2021): 1204–12. http://dx.doi.org/10.1108/aeat-02-2021-0058.
Pełny tekst źródłaStreszczenie:
Purpose This paper aims to propose a multi-agent approach to adaptive control of fixed-wing unmanned aerial vehicles (UAVs) tracking a moving ground target. The approach implies that the UAVs in a single group must maintain preset phase shift angles while rotating around the target so as to evaluate the target’s movement more accurately. Thus, the controls should ensure that the UAV swarm follows a moving circular path whose center is the target while also attaining and maintaining a circular formation of a specific geometric shape; and the formation control system is capable of self-tuning because the UAV dynamics is uncertain. Design/methodology/approach This paper considers two interaction architectures: an open-chain where each UAV only interacts with its neighbors; and a cooperative leader, where the leading UAV is involved in attaining the formation. The cooperative controllers are self-tuned by fuzzy model reference adaptive control (MRAC). Findings Using open-chain decentralized architecture allows to have an unlimited number of aircraft in a formation, which is in line with the swarm behavior concept. The approach was tested for efficiency and performance in various scenarios using complete nonlinear flying-wing UAV models equipped with configured standard autopilot models. Research limitations/implications Assume the target follows a rectilinear trajectory at a constant speed. The speed is supposed to be known in advance. Another assumption is that the weather is windless. Originality/value In contrast to known studies, this one uses Lyapunov guidance vector fields that are direction- and magnitude-nonuniform. The overall cooperative controller structure is based on a decentralized and centralized consensus.
19
Safwat, Ehab, Weiguo Zhang, Ahmed Mohsen i Mohamed Kassem. "Design and Analysis of a Robust UAV Flight Guidance and Control System Based on a Modified Nonlinear Dynamic Inversion". Applied Sciences 9, nr 17 (2.09.2019): 3600. http://dx.doi.org/10.3390/app9173600.
Pełny tekst źródłaStreszczenie:
The work presented in this paper focuses on the design of a robust nonlinear flight control system for a small fixed-wing UAV against uncertainties and external disturbances. Toward this objective, an integrated UAV waypoints guidance scheme based on Carrot Chasing guidance law (CC) in comparison with the pure pursuit and line of sight-based path following (PLOS) guidance law is analyzed. For path following based on CC, a Virtual Track Point (VTP) is introduced on the path to let the UAV chase the path. For PLOS, the pure pursuit guidance law directs the UAV to the next waypoint, while the LOS guidance law steers the vehicle toward the line of sight (LOS). Nonlinear Dynamic Inversion (NLDI) awards the flight control system researchers a straight forward method of deriving control laws for nonlinear systems. The control inputs are used to eliminate unwanted terms in the equations of motion using negative feedback of these terms. The two-time scale assumption is adopted here to separate the fast dynamics—three angular rates of aircraft—from the slow dynamics—the angle of attack, sideslip, and bank angles. However, precise dynamic models may not be available, therefore a modification of NLDI is presented to compensate the model uncertainties. Simulation results show that the modified NLDI flight control system is robust against wind disturbances and model mismatch. PLOS path-following technique more accurately follows the desired path than CC and also requires the least control effort.
20
Lee, C. S., W. L. Chan, S. S. Jan i F. B. Hsiao. "A linear-quadratic-Gaussian approach for automatic flight control of fixed-wing unmanned air vehicles". Aeronautical Journal 115, nr 1163 (styczeń 2011): 29–41. http://dx.doi.org/10.1017/s0001924000005340.
Pełny tekst źródłaStreszczenie:
AbstractThis paper presents the design and implementation of automatic flight controllers for a fixed-wing unmanned air vehicle (UAV) by using a linear-quadratic-Gaussian (LQG) control approach. The LQG design is able to retain the guaranteed closed-loop stability of the linear-quadratic regulator (LQR) while having incomplete state measurement. Instead of feeding back the actual states to form the control law, the estimated states provided by a separately designed optimal observer, i.e. the Kalman filter are used. The automatic flight controllers that include outer-loop controls are constructed based on two independent LQG regulators which govern the longitudinal and lateral dynamics of the UAV respectively. The resulting controllers are structurally simple and thus efficient enough to be easily realized with limited onboard computing resource. In this paper, the design of the LQG controllers is described while the navigation and guidance algorithm based on Global Positioning System (GPS) data is also outlined. In order to validate the performance of the automatic flight control system, a series of flight tests have been conducted. Significant results are presented and discussed in detail. Overall, the flight-test results show that it is highly feasible and effective to apply the computationally efficient LQG controllers on a fixed-wing UAV system with a relatively simple onboard system. On the other hand, a fully automatic 44km cross-sea flight demonstration was successfully conducted using the LQG-based flight controllers. Detailed description regarding the event and some significant flight data are given.
21
Wu, Kun, Zhihao Cai, Jiang Zhao i Yingxun Wang. "Target Tracking Based on a Nonsingular Fast Terminal Sliding Mode Guidance Law by Fixed-Wing UAV". Applied Sciences 7, nr 4 (29.03.2017): 333. http://dx.doi.org/10.3390/app7040333.
Pełny tekst źródła
22
Samaniego, Franklin, Javier Sanchis, Sergio Garcia-Nieto i Raul Simarro. "Smooth 3D Path Planning by Means of Multiobjective Optimization for Fixed-Wing UAVs". Electronics 9, nr 1 (28.12.2019): 51. http://dx.doi.org/10.3390/electronics9010051.
Pełny tekst źródłaStreszczenie:
Demand for 3D planning and guidance algorithms is increasing due, in part, to the increase in unmanned vehicle-based applications. Traditionally, two-dimensional (2D) trajectory planning algorithms address the problem by using the approach of maintaining a constant altitude. Addressing the problem of path planning in a three-dimensional (3D) space implies more complex scenarios where maintaining altitude is not a valid approach. The work presented here implements an architecture for the generation of 3D flight paths for fixed-wing unmanned aerial vehicles (UAVs). The aim is to determine the feasible flight path by minimizing the turning effort, starting from a set of control points in 3D space, including the initial and final point. The trajectory generated takes into account the rotation and elevation constraints of the UAV. From the defined control points and the movement constraints of the UAV, a path is generated that combines the union of the control points by means of a set of rectilinear segments and spherical curves. However, this design methodology means that the problem does not have a single solution; in other words, there are infinite solutions for the generation of the final path. For this reason, a multiobjective optimization problem (MOP) is proposed with the aim of independently maximizing each of the turning radii of the path. Finally, to produce a complete results visualization of the MOP and the final 3D trajectory, the architecture was implemented in a simulation with Matlab/Simulink/flightGear.
23
Deng, Zhao, Liaoni Wu i Yancheng You. "Modeling and Design of an Aircraft-Mode Controller for a Fixed-Wing VTOL UAV". Mathematical Problems in Engineering 2021 (29.09.2021): 1–17. http://dx.doi.org/10.1155/2021/7902134.
Pełny tekst źródłaStreszczenie:
Vertical takeoff and landing (VTOL) is an essential feature of unmanned aerial vehicles (UAVs). On the one hand, VTOL can expand and enhance the applications of UAVs; yet, on the other hand, it makes the design of control systems for UAVs more complicated. The most challenging demand in designing the control system is to achieve satisfactory response sharpness of fixed-wing UAVs to control commands and ensure that the aircraft mode channels are effectively decoupled. In this work, a six-degree-of-freedom (6-DoF) model with forces and moments is established based on the aerodynamic analysis, which is carried out through computational fluid dynamics (CFD) numerical simulation. The improved proportional derivative (PD) controller based on the extended state observer (ESO) is proposed to design the inner-loop attitude control, which increases the anti-interference ability for internal and external uncertainty of the UAV system. The motion equations of the UAV are established and divided into independent components of longitudinal and lateral motion to design the outer loop control law under minor disturbance conditions. A total energy control system (TECS) for the longitudinal height channel is proposed, which separates speed control and track control. L1 nonlinear path tracking guidance algorithm is used for lateral trajectory tracking so as to improve curve tracking ability and wind resistance. Effectiveness of this approach is proved by actual flight experiment data. Finally, a controller based on angular velocity control is designed to prevent the attitude and head reference system (AHRS) from malfunctioning. Its effectiveness is verified by the response test of the control system.
24
Kayacan, Erdal, Mojtaba Ahmadieh Khanesar, Jaime Rubio-Hervas i Mahmut Reyhanoglu. "Learning Control of Fixed-Wing Unmanned Aerial Vehicles Using Fuzzy Neural Networks". International Journal of Aerospace Engineering 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/5402809.
Pełny tekst źródłaStreszczenie:
A learning control strategy is preferred for the control and guidance of a fixed-wing unmanned aerial vehicle to deal with lack of modeling and flight uncertainties. For learning the plant model as well as changing working conditions online, a fuzzy neural network (FNN) is used in parallel with a conventional P (proportional) controller. Among the learning algorithms in the literature, a derivative-free one, sliding mode control (SMC) theory-based learning algorithm, is preferred as it has been proved to be computationally efficient in real-time applications. Its proven robustness and finite time converging nature make the learning algorithm appropriate for controlling an unmanned aerial vehicle as the computational power is always limited in unmanned aerial vehicles (UAVs). The parameter update rules and stability conditions of the learning are derived, and the proof of the stability of the learning algorithm is shown by using a candidate Lyapunov function. Intensive simulations are performed to illustrate the applicability of the proposed controller which includes the tracking of a three-dimensional trajectory by the UAV subject to time-varying wind conditions. The simulation results show the efficiency of the proposed control algorithm, especially in real-time control systems because of its computational efficiency.
25
Ruggles, Samantha, Joseph Clark, Kevin W. Franke, Derek Wolfe, Brandon Reimschiissel, R. Abraham Martin, Trent J. Okeson i John D. Hedengren. "Comparison of SfM computer vision point clouds of a landslide derived from multiple small UAV platforms and sensors to a TLS-based model". Journal of Unmanned Vehicle Systems 4, nr 4 (1.12.2016): 246–65. http://dx.doi.org/10.1139/juvs-2015-0043.
Pełny tekst źródłaStreszczenie:
Structure from motion (SfM) computer vision is a remote sensing method that is gaining popularity due to its simplicity and ability to accurately characterize site geometry in three dimensions (3D). While many researchers have demonstrated the potential for SfM to be used with unmanned aerial vehicles (UAVs) to model in 3D various geologic features, such as landslides, little is understood concerning how the selection of the UAV platform can affect the resolution and accuracy of the model. This study evaluates the resolution and accuracy of 3D point cloud models of a large landslide that occurred in 2013 near Page, Arizona, that were developed from various small UAV platform and camera configurations. Terrestrial laser scans were performed at the landslide and were used to establish a comparative baseline model. Results from the study indicate that point cloud resolution improved by more than 16% when using multi-rotor UAVs instead of fixed-wing UAVs. However, accuracy of the points in the point cloud model appear to be independent of the UAV platform, but depend principally on the selected camera and the image resolution. Additional practical guidance on flying various UAV platforms in challenging field conditions is provided for geologists and engineers.
26
WU, Weinan, i Naigang Cui. "A distributed and integrated method for cooperative mission planning of multiple heterogeneous UAVs". Aircraft Engineering and Aerospace Technology 90, nr 9 (14.11.2018): 1403–12. http://dx.doi.org/10.1108/aeat-05-2017-0124.
Pełny tekst źródłaStreszczenie:
Purpose The purpose of this paper is to develop a distributed and integrated method to get a fast and feasible solution for cooperative mission planning of multiple heterogeneous unmanned aerial vehicles (UAVs). Design/methodology/approach In this study, the planning process is conducted in a distributed framework; the cooperative mission planning problem is reformulated with some specific constraints in the real mission; a distributed genetic algorithm is the algorithm proposed for searching for the optimal solution; genes of the chromosome are modified to adapt to the heterogeneous characteristic of UAVs; a fixed-wing UAV’s six degrees-of-freedom (DOF) model with a path following method is used to test the proposed mission planning method. Findings This method not only has the ability to obtain good feasible solutions but also improves the operating rate vastly. Research limitations/implications This study is only applied to the case where the communication among UAVs is linked during the mission. Practical implications This study is expected to be practical for a real mission because of its fast operating rate and good feasible solution. Originality/value This solution is tested on a fixed-wing UAV’s 6-DOF model by a path following method, so it is believable from the perspective of an autonomous UAV guidance and control system.
27
Alturbeh, Hamid, i James F. Whidborne. "Visual Flight Rules-Based Collision Avoidance Systems for UAV Flying in Civil Aerospace". Robotics 9, nr 1 (25.02.2020): 9. http://dx.doi.org/10.3390/robotics9010009.
Pełny tekst źródłaStreszczenie:
The operation of Unmanned Aerial Vehicles (UAVs) in civil airspace is restricted by the aviation authorities, which require full compliance with regulations that apply for manned aircraft. This paper proposes control algorithms for a collision avoidance system that can be used as an advisory system or a guidance system for UAVs that are flying in civil airspace under visual flight rules. A decision-making system for collision avoidance is developed based on the rules of the air. The proposed architecture of the decision-making system is engineered to be implementable in both manned aircraft and UAVs to perform different tasks ranging from collision detection to a safe avoidance manoeuvre initiation. Avoidance manoeuvres that are compliant with the rules of the air are proposed based on pilot suggestions for a subset of possible collision scenarios. The proposed avoidance manoeuvres are parameterized using a geometric approach. An optimal collision avoidance algorithm is developed for real-time local trajectory planning. Essentially, a finite-horizon optimal control problem is periodically solved in real-time hence updating the aircraft trajectory to avoid obstacles and track a predefined trajectory. The optimal control problem is formulated in output space, and parameterized by using B-splines. Then the optimal designed outputs are mapped into control inputs of the system by using the inverse dynamics of a fixed wing aircraft.
28
Zhang, Zhitao, Changchuan Xie, Wei Wang i Chao An. "An Experimental and Numerical Evaluation of the Aerodynamic Performance of a UAV Propeller Considering Pitch Motion". Drones 7, nr 7 (6.07.2023): 447. http://dx.doi.org/10.3390/drones7070447.
Pełny tekst źródłaStreszczenie:
Considering the vibration generated by a propeller-driven UAV or encountering gust, the propeller will perform a very complex follower motion. A pitch and rotating coupled motion is proposed in the present work that can take more complex unsteady performance of follower force than a regular fixed-point rotating motion. In order to evaluate the unsteady follower force and conduct parametric study, an extensive ground test bench was designed for this purpose where the whole test system was driven by a linear servo actuator and the follower force was measured by a 6-component balance. For CFD simulation, coupled motion in particular needs detailed unsteady aerodynamic model; therefore, a high-fidelity CFD-based study integrated with the overset mesh method was complemented to solve the unsteady fluid of varying conditions. The results suggest that a significant influence on unsteady follower force is observed, and the mean value of in-plane force does not equal to zero during the coupled motion process. Compared with the regular fixed-point rotation of propeller, the fluctuation frequency of follower force in present work couples the rotation and pitch motion frequencies. In addition, the oscillation amplitude of out-plane force and torque is positively related with the pitch frequency, pitch amplitude, and relative length from leading edge of wing to the rotation center. For example, the oscillation amplitude of 1-blade’s out-plane force and torque increases by 57.122% and 66.542% for the 5 Hz-5 deg case compared with the 5 Hz-3 deg case, respectively. However, the torque is not sensitive to frequency of pitch motion. The generally excellent agreement evident between the ground test and numerical simulation results is important as guidance for our future investigation on “dynamic” aerodynamic performance of a propeller-driven UAV.
29
Pogorzelski, G., i F. J. Silvestre. "Autonomous soaring using a simplified MPC approach". Aeronautical Journal 123, nr 1268 (15.03.2019): 1666–700. http://dx.doi.org/10.1017/aer.2019.6.
Pełny tekst źródłaStreszczenie:
ABSTRACTThe need for efficient propulsion systems allied to increasingly more challenging fixed-wing UAV mission requirements has led to recent research on the autonomous thermal soaring field with promising results. As part of that effort, the feasibility and advantages of model predictive control (MPC)-based guidance and control algorithms capable of extracting energy from natural occurring updrafts have already been demonstrated numerically. However, given the nature of the dominant atmospheric phenomena and the amplitude of the required manoeuvres, a non-linear optimal control problem results. Depending on the adopted prediction horizon length, it may be of large order, leading to implementation and real-time operation difficulties. Knowing that, an alternative MPC-based autonomous thermal soaring controller is presented herein. It is designed to yield a simple and small non-linear programming problem to be solved online. In order to accomplish that, linear prediction schemes are employed to impose the differential constraints, thus no extra variables are added to the problem and only linear bound restrictions result. For capturing the governing non-linear effects during the climb phase, a simplified representation of the aircraft kinematics with quasi-steady corrections is used by the controller internal model. Flight simulation results using a 3 degree-of-freedom model subjected to a randomly generated time varying thermal environment show that the aircraft is able to locate and exploit updrafts, suggesting that the proposed algorithm is a feasible MPC strategy to be employed in a practical application.
30
Zhao, Yu, Jifeng Guo, Chengchao Bai i Hongxing Zheng. "Reinforcement Learning-Based Collision Avoidance Guidance Algorithm for Fixed-Wing UAVs". Complexity 2021 (16.01.2021): 1–12. http://dx.doi.org/10.1155/2021/8818013.
Pełny tekst źródłaStreszczenie:
A deep reinforcement learning-based computational guidance method is presented, which is used to identify and resolve the problem of collision avoidance for a variable number of fixed-wing UAVs in limited airspace. The cooperative guidance process is first analyzed for multiple aircraft by formulating flight scenarios using multiagent Markov game theory and solving it by machine learning algorithm. Furthermore, a self-learning framework is established by using the actor-critic model, which is proposed to train collision avoidance decision-making neural networks. To achieve higher scalability, the neural network is customized to incorporate long short-term memory networks, and a coordination strategy is given. Additionally, a simulator suitable for multiagent high-density route scene is designed for validation, in which all UAVs run the proposed algorithm onboard. Simulated experiment results from several case studies show that the real-time guidance algorithm can reduce the collision probability of multiple UAVs in flight effectively even with a large number of aircraft.
31
Kalra, Arti, Sreenatha Anavatti i Radhakant Padhi. "Aggressive Formation Flying of Fixed-Wing UAVs with Differential Geometric Guidance". Unmanned Systems 05, nr 02 (kwiecień 2017): 97–113. http://dx.doi.org/10.1142/s2301385017500078.
Pełny tekst źródłaStreszczenie:
A nonlinear differential geometric guidance scheme is presented in this paper for aggressive autonomous formation flying of fixed-wing unmanned aerial vehicles (UAVs) in the leader-follower framework. It is assumed that the desired location of the followers are known in the velocity frame of the leader. It is also assumed that the followers can also access the position, velocity and acceleration parameters of the leader as necessary auxiliary information. By utilizing this information and manipulating their own dynamics, the proposed logic autonomously guides the followers to their respective desired positions. Depending on the leader’s velocity and acceleration information as well as the intended relative location, the formulation also ensures an appropriate direction of the velocity vectors of the followers at the desired relative locations, including its rate of change if any. This leads to minimal transient effects while maintaining the formation even under maneuvering conditions. Usage of quaternions and other innovations ensure that the formulation is singularity-free and hence formation flying is ensured even under aggressive maneuvers of the leader without any restriction on its velocity vector direction. The desired thrust, angle of attack and bank angle are generated using a nonlinear point mass model of a vehicle. The generated guidance commands are then realized using a nonlinear six-DOF model, making the formulation practically more relevant. Extensive simulation studies demonstrate that the proposed approach is capable of bringing the UAVs from arbitrary initial locations to the desired formation and then maintaining the formation even under highly agile motion of the leader.
32
Coates, Erlend M., i Thor I. Fossen. "Geometric Reduced-Attitude Control of Fixed-Wing UAVs". Applied Sciences 11, nr 7 (1.04.2021): 3147. http://dx.doi.org/10.3390/app11073147.
Pełny tekst źródłaStreszczenie:
This paper presents nonlinear, singularity-free autopilot designs for multivariable reduced-attitude control of fixed-wing aircraft. To control roll and pitch angles, we employ vector coordinates constrained to the unit two-sphere and that are independent of the yaw/heading angle. The angular velocity projected onto this vector is enforced to satisfy the coordinated-turn equation. We exploit model structure in the design and prove almost global asymptotic stability using Lyapunov-based tools. Slowly-varying aerodynamic disturbances are compensated for using adaptive backstepping. To emphasize the practical application of our result, we also establish the ultimate boundedness of the solutions under a simplified controller that only depends on rough estimates of the control-effectiveness matrix. The controller design can be used with state-of-the-art guidance systems for fixed-wing unmanned aerial vehicles (UAVs) and is implemented in the open-source autopilot ArduPilot for validation through realistic software-in-the-loop (SITL) simulations.
33
Lehr, William J. "THE POTENTIAL USE OF SMALL UAS IN SPILL RESPONSE". International Oil Spill Conference Proceedings 2008, nr 1 (1.05.2008): 431–33. http://dx.doi.org/10.7901/2169-3358-2008-1-431.
Pełny tekst źródłaStreszczenie:
ABSTRACT For the last several decades, the sensors available for remote sensing of oil spills have changed significantly while the platforms for these sensors have remained unaltered. The limitations on these platforms are well known. Satellites are expensive, remote, and inflexible. Fixed-wing aircraft cannot hover easily over the spill site and often fly too fast for good observations. Helicopters are expensive, require specially trained pilots, and can be more hazardous than other alternatives. Unmanned aircraft systems (UAS) provide a potentially new alternative platform for monitoring spill location and clean-up operations. The aircraft (also called unmanned aerial or airborne vehicles) fit into three general categories. Very large aircraft require much or more of the infrastructure of manned aircraft and will probably be deployed only in spills of national significance. Mid-range vehicles have proven their worth monitoring forests fires, emergencies with many similar requirements to oil spills, but still require designated landing and take-off facilities. A rapidly expanding category is the very small UAS that can be field launched and recovered. The range, guidance, and sensor availability of these aircraft have improved considerably from early prototypes. This paper explores the possibility of incorporating particularly these smaller UAS into spill response. Potential roadblocks include weather limitations, operator training, payload restrictions and regulatory restrictions. This last roadblock is presently the most difficult to overcome although re-consideration at the Federal Aviation Administration could modify existing regulations, making use of low-flying unmanned aircraft more plausible. Assuming the necessary regulatory changes, the paper explores typical applications and expected benefits from such system.
34
Park, Sanghyuk. "Rendezvous Guidance on Circular Path for Fixed-Wing UAV". International Journal of Aeronautical and Space Sciences, 30.04.2020. http://dx.doi.org/10.1007/s42405-020-00281-8.
Pełny tekst źródła
35
He, Mo, Xiaogang Wang i Naigang Cui. "Modified vector field and nonlinear guidance law for low-cost UAV path following". Aircraft Engineering and Aerospace Technology, 22.06.2022. http://dx.doi.org/10.1108/aeat-03-2019-0045.
Pełny tekst źródłaStreszczenie:
Purpose The purpose of this paper is to present a high accuracy path following method for low-cost fixed-wing UAVs. Design/methodology/approach The original vector field (VF) algorithm is condensed. A spatial integration mechanism is added to the existing VF and nonlinear guidance law, aiming to decrease steady-state cross-track-error and cope with long-term disturbance. Findings Numerical simulations show the proposed method could diminish steady-state cross-track-error effectively. Test flights show the proposed method is applicable on low-cost fixed-wing UAVs. Practical implications The path following accuracy shown in simulations and test flights indicates the proposed method could be deployed in scenarios including inflight rendezvous, formation, trafficway take-off and landing. Originality/value This paper provides an improved high-accuracy path following method for low-cost fixed-wing UAVs.
36
Wang, Ximan, Simone Baldi, Xuewei Feng, Changwei Wu, Hongwei Xie i Bart De Schutter. "A Fixed-Wing UAV Formation Algorithm Based on Vector Field Guidance". IEEE Transactions on Automation Science and Engineering, 2022, 1–14. http://dx.doi.org/10.1109/tase.2022.3144672.
Pełny tekst źródła
37
"Fixed-wing UAV guidance law for ground target over-flight tracking". Journal of Systems Engineering and Electronics 30, nr 2 (2019): 384. http://dx.doi.org/10.21629/jsee.2019.02.16.
Pełny tekst źródła
38
Zhang, Min, Pengfei Tian, Xin Chen i Xin Wang. "Ground Target Tracking Guidance Law for Fixed-Wing Unmanned Aerial Vehicle: A Search and Capture Approach". Journal of Dynamic Systems, Measurement, and Control 139, nr 10 (28.06.2017). http://dx.doi.org/10.1115/1.4036563.
Pełny tekst źródłaStreszczenie:
One important problem for unmanned aerial vehicles (UAVs) in mission applications is to track ground targets automatically. A major concern is how to keep the tracking process stable and efficient while the motion of the ground targets changes rapidly. In this brief, a new guidance strategy for the ground target “Search and Capture” based on a virtual target is proposed. First, a virtual trajectory, which is composed of straight lines and arcs, is generated based on the motion of the target. The straight lines are used to capture, while the arcs are used to search, and switch between straight line and arc when some condition is met; second, we design a new guidance law based on line-of-sight (LOS) which makes a UAV to track the virtual target automatically. This new method solves the following three problems simultaneously: (1) The UAV always keeps a constant speed to track the target with changing velocity, (2) the generated trajectory meets the flight constraints of the UAV, and (3) the speed range of the ground target can be from the stationary to almost the maximum cruising speed of the UAV. Simulation results show that the proposed guidance strategy can achieve stable tracking for various motions of the ground target.
39
Sai-fei, Wu, Wang Xin-hua, Bai Jun-jie i Tan Qing-yan. "Autonomous Landing of a Fixed Wing UAV with a Ground-based Visual Guidance System". DEStech Transactions on Engineering and Technology Research, ICMITE2016 (21.12.2016). http://dx.doi.org/10.12783/dtetr/icmite20162016/4599.
Pełny tekst źródła
40
Gryte, Kristoffer, Martin L. Sollie i Tor Arne Johansen. "Control System Architecture for Automatic Recovery of Fixed-Wing Unmanned Aerial Vehicles in a Moving Arrest System". Journal of Intelligent & Robotic Systems 103, nr 4 (29.11.2021). http://dx.doi.org/10.1007/s10846-021-01521-z.
Pełny tekst źródłaStreszczenie:
AbstractAutomatic recovery is an important step in enabling fully autonomous missions using fixed-wing unmanned aerial vehicles (UAVs) operating from ships or other moving platforms. However, automatic recovery in moving arrest systems is only briefly studied in the research literature, and is not yet an option when using low-cost, commercial off-the-shelf (COTS) autopilots. Acknowledging the reliability and low cost of COTS avionics, this paper adds recovery functionality as a modular extension based on non-intrusive additions to an autopilot with very general assumptions on its interface. This is achieved by line-of-sight guidance, which sends an augmented desired position to the autopilot, to ensure line-following along a virtual runway that guides the UAV into the arrest system. The translation and rotation of this line is determined by the pose of the arrest system, determined using two Global Navigation Satellite System (GNSS) receivers, where one is configured as a Real-Time Kinematic (RTK) base station. The relative position of the UAV and arrest system is also precisely estimated using RTK GNSS. Through extensive field testing, on two different fixed-wing UAVs, the system has shown its performance and reliability; 43 recovery attempts in a stationary net hit 0.01 ± 0.25m to the right and 0.07 ± 0.20m below the target in calm conditions. Further, 15 recoveries in a barge-mounted, ship-towed net hit 0.06 ± 0.53m to the right and 0.98 ± 0.27m below the target in winds up to 4 m/s. The remaining error is largely systematic, caused by communication delays, and could be reduced with more integral effect or through direct compensation.
41
Kim, Taerim, i Sanghyuk Park. "Fast Converging Circling Guidance for Fixed-Wing UAVs". International Journal of Aeronautical and Space Sciences, 22.06.2023. http://dx.doi.org/10.1007/s42405-023-00625-0.
Pełny tekst źródła
42
Kim, Suhyeon, Hyeongjun Cho i Dongwon Jung. "Circular Formation Guidance of Fixed-wing UAVs using Mesh Network". IEEE Access, 2022, 1. http://dx.doi.org/10.1109/access.2022.3218673.
Pełny tekst źródła
43
Yang, Yachao, Chang Liu, Jie Li, Yu Yang, Juan Li, Zhidong Zhang i Bobo Ye. "Design, implementation, and verification of a low‐cost terminal guidance system for small fixed‐wing UAVs". Journal of Field Robotics, 12.01.2021. http://dx.doi.org/10.1002/rob.22012.
Pełny tekst źródła