Conceptual Design, Modeling, and Control Strategies of Drones

A special issue of Drones (ISSN 2504-446X). This special issue belongs to the section "Drone Design and Development".

Deadline for manuscript submissions: closed (31 January 2022) | Viewed by 91434

Special Issue Editors


E-Mail Website
Guest Editor
School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW 2052, Australia
Interests: robot navigation; deployment of drones; unmanned aerial vehicles; control of wireless communication networks; control of power systems; robust control and filtering; hybrid dynamical systems; control engineering; biomedical engineering
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Mechanical Engineering; New Mexico Institute of Mining and Technology, Socorro, NM 87801, USA
Interests: robotics and control; multi-agent systems; uncertainty quantification; optimization; asynchronous algorithm
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The use of aerial drones, also known as flying robots, unmanned aerial vehicles (UAVs) or airships, is rapidly expanding to numerous applications, such as communication, environmental monitoring, rescue operations, policing, video surveillance, product deliveries and smart agriculture. For all these applications, conceptual design, modelling and control strategies of aerial drones are critical issues. Advanced methods of modelling, navigation and control play an important role in achieving the reliable, robust, secure and cost-effective functioning of aerial drones. This Special Issue is focused on new developments in the field of modelling, navigation and control strategies for various applications. Potential topics include but are not limited to UAV control systems, advanced methods of UAV navigation and guidance, mathematical models of aerial drones, control and navigation of aerial drones for surveillance, environmental, delivery, rescue, smart agriculture, policing and security applications.

Prof. Dr. Andrey V. Savkin
Prof. Dr. Kooktae Lee
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Drones is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Navigation of aerial drones
  • Advanced control of aerial drones
  • UAV path planning
  • Modelling of drones
  • UAV control systems
  • Applications of aerial drones
  • UAV surveillance and monitoring
  • Collision-free navigation and control of aerial drones

Related Special Issue

Published Papers (19 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

25 pages, 11413 KiB  
Article
Inverted Docking Station: A Conceptual Design for a Battery-Swapping Platform for Quadrotor UAVs
by Sudam Chamikara De Silva, Maroay Phlernjai, Suchada Rianmora and Photchara Ratsamee
Drones 2022, 6(3), 56; https://doi.org/10.3390/drones6030056 - 23 Feb 2022
Cited by 14 | Viewed by 7785
Abstract
“Flight Time” and the “Scope of the mission” play major roles in using UAVs as they affect most industrial activities. Once the battery has depleted, the UAV has to land on the ground and human interaction is needed to change the battery with [...] Read more.
“Flight Time” and the “Scope of the mission” play major roles in using UAVs as they affect most industrial activities. Once the battery has depleted, the UAV has to land on the ground and human interaction is needed to change the battery with a fully charged one. Nowadays, several automatic battery swapping systems are catching interest in research. This research presents the novel concept of an Inverted Docking Station that allows a quadrotor UAV to attach to the ceiling during the automatic battery-swapping process. The proposed design consist of a docking station, a positioning system and gripper mechanisms. The proposed design allows the quadrotor to carry the load under the quadrotor and remain attached throughout the servicing period. A mathematical model and design guideline have been proposed, and a Finite Element Analysis (FEA) was performed to check that the developed platform is strong enough to withstand the above task. A ‘DJI TELLO’ small-scale quadrotor was chosen as a case study to demonstrate the proposed research. Finally the advantages and the limitations of the system are discussed. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

18 pages, 6608 KiB  
Article
Local Control of Unmanned Air Vehicles in the Mountain Area
by Pavol Kurdel, Marek Češkovič, Natália Gecejová, František Adamčík and Mária Gamcová
Drones 2022, 6(2), 54; https://doi.org/10.3390/drones6020054 - 21 Feb 2022
Cited by 22 | Viewed by 3366
Abstract
The task of increasing the accuracy and stabilization of the flight of unmanned aerial vehicles (UAV) in the alpine environment is a complex problem. It is related to the evaluation of UAV flight parameters and control conditions for the operator’s place. The purpose [...] Read more.
The task of increasing the accuracy and stabilization of the flight of unmanned aerial vehicles (UAV) in the alpine environment is a complex problem. It is related to the evaluation of UAV flight parameters and control conditions for the operator’s place. The purpose of the UAV’s autonomous flight control is to ensure stable control of the UAV’s flight parameters. Flight control systems are affected by various disturbances caused by both internal and external conditions. In general, the number of autonomous control systems corresponds to the number of degrees of freedom, which determines the flight of an autonomous vehicle. An important factor in assessing the quality of such a UAV is its readiness for an autonomous flight together with the level of its safe guidance on the route. The presented article focuses on the analysis of UAV flight control and the quality of prediction and elimination of errors that exist during maneuvers toward the place of a successful UAV landing. The aim of the article is to point out the solvability of the complexities of such a flight procedure with the evaluation of the readiness for the descent phase of the autonomous UAV. The given problem is caused by the social demand for the creation of a way of providing health care in the mountain area of the High Tatras in Slovakia. The existing database of data obtained from the flying vehicles used in Slovakia was compared with the data obtained from the simulated flights, with their subsequent evaluation in the MATLAB software (Version R2021b) environment. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

18 pages, 1806 KiB  
Article
Homogeneous Agent Behaviours for the Multi-Agent Simultaneous Searching and Routing Problem
by Thomas Kent, Arthur Richards and Angus Johnson
Drones 2022, 6(2), 51; https://doi.org/10.3390/drones6020051 - 17 Feb 2022
Cited by 4 | Viewed by 2524
Abstract
Through the use of autonomy Unmanned Aerial Vehicles (UAVs) can be used to solve a range of of multi-agent problems that exist in the real world, for example search and rescue or surveillance. Within these scenarios the global objective might often be better [...] Read more.
Through the use of autonomy Unmanned Aerial Vehicles (UAVs) can be used to solve a range of of multi-agent problems that exist in the real world, for example search and rescue or surveillance. Within these scenarios the global objective might often be better achieved if aspects of the problem can be optimally shared amongst its agents. However, in uncertain, dynamic and often partially observable environments centralised global-optimisation techniques are not achievable. Instead, agents may have to act on their own belief of the world, making the best decisions independently and potentially myopically. With multiple agents acting in a decentralised manner how can we discourage competitive behaviour and instead facilitate cooperation. This paper focuses on the specific problem of multiple UAVs simultaneously searching for tasks in an environment whilst efficiently routing between them and ultimately visiting them. This paper is motivated by this idea that collaboration can be simple and achieved without the need for a dialogue but instead through the design of the individual agent’s behaviour. By focusing on what is communicated we expand the use of a single agent behaviour. Which through minor modifications can produce distinct agents demonstrating independent, collaborative and competitive behaviour. In particular by investigating the role of sensor and communication ranges this paper will show that increased sensor ranges can be detrimental to system performance, and instead the simple modelling of nearby agents’ intent is a far better approach. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

12 pages, 18782 KiB  
Article
Thrust Vector Observation for Force Feedback-Controlled UAVs
by Lennart Werner, Michael Strohmeier, Julian Rothe and Sergio Montenegro
Drones 2022, 6(2), 49; https://doi.org/10.3390/drones6020049 - 17 Feb 2022
Viewed by 4722
Abstract
This paper presents a novel approach to Thrust Vector Control (TVC) for small Unmanned Aerial Vehicles (UAVs). The difficulties associated with conventional feed-forward TVC are outlined, and a practical solution to conquer these challenges is derived. The solution relies on observing boom deformations [...] Read more.
This paper presents a novel approach to Thrust Vector Control (TVC) for small Unmanned Aerial Vehicles (UAVs). The difficulties associated with conventional feed-forward TVC are outlined, and a practical solution to conquer these challenges is derived. The solution relies on observing boom deformations that are created by different thrust vector directions and high-velocity air inflow. The paper describes the required measurement electronics as well as the implementation of a dedicated testbed that allows the evaluation of mid-flight force measurements. Wind-tunnel tests show that the presented method for active thrust vector determination is able to quantify the disturbances due to the incoming air flow. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

24 pages, 1560 KiB  
Article
Robust Hierarchical Formation Control of Unmanned Aerial Vehicles via Neural-Based Observers
by Yang Fei, Yuan Sun and Peng Shi
Drones 2022, 6(2), 40; https://doi.org/10.3390/drones6020040 - 06 Feb 2022
Cited by 2 | Viewed by 2906
Abstract
Herein, we investigate the robust formation control problem for a group of unmanned aerial vehicles (UAVs) with system uncertainty. A hierarchical formation control strategy is introduced to ensure the uniform ultimate boundedness of each UAV’s reference tracking error. First, a group of saturated [...] Read more.
Herein, we investigate the robust formation control problem for a group of unmanned aerial vehicles (UAVs) with system uncertainty. A hierarchical formation control strategy is introduced to ensure the uniform ultimate boundedness of each UAV’s reference tracking error. First, a group of saturated high-level virtual agents are defined to act as the trajectory planners that offer feasible position references to the actual UAVs. A sliding mode neural-based observer is then constructed to estimate the nonlinear uncertainty in the UAV model. Furthermore, sliding mode controllers are designed for both the position loop and the attitude loop of the UAV. To attenuate the chattering phenomenon in the control input, a saturated and smoothed differentiator is proposed along with an observation introduction function. The effectiveness of the proposed control scheme is validated by both the Lyapunov stability theory and numerical simulations based on a multiple-UAV system. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

34 pages, 9688 KiB  
Article
Distributed 3D Navigation of Swarms of Non-Holonomic UAVs for Coverage of Unsteady Environmental Boundaries
by Alexey S. Matveev and Anna A. Semakova
Drones 2022, 6(2), 33; https://doi.org/10.3390/drones6020033 - 20 Jan 2022
Cited by 4 | Viewed by 2626
Abstract
A team of non-holonomic constant-speed under-actuated unmanned aerial vehicles (UAVs) with lower-limited turning radii travel in 3D. The space hosts an unknown and unpredictably varying scalar environmental field. A space direction is given; this direction and the coordinate along it are conditionally termed [...] Read more.
A team of non-holonomic constant-speed under-actuated unmanned aerial vehicles (UAVs) with lower-limited turning radii travel in 3D. The space hosts an unknown and unpredictably varying scalar environmental field. A space direction is given; this direction and the coordinate along it are conditionally termed as the “vertical” and “altitude”, respectively. All UAVs should arrive at the moving and deforming isosurface where the field assumes a given value. They also should evenly distribute themselves over a pre-specified range of the “altitudes” and repeatedly encircle the entirety of the isosurface while remaining on it, each at its own altitude. Every UAV measures only the field intensity at the current location and both the Euclidean and altitudinal distances to the objects (including the top and bottom of the altitudinal range) within a finite range of visibility and has access to its own speed and the vertical direction. The UAVs carry no communication facilities, are anonymous to one another, and cannot play distinct roles in the team. A distributed control law is presented that solves this mission under minimal and partly inevitable assumptions. This law is justified by a mathematically rigorous global convergence result; computer simulation tests confirm its performance. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

22 pages, 1869 KiB  
Article
Robotic Herding of Farm Animals Using a Network of Barking Aerial Drones
by Xiaohui Li, Hailong Huang, Andrey V. Savkin and Jian Zhang
Drones 2022, 6(2), 29; https://doi.org/10.3390/drones6020029 - 19 Jan 2022
Cited by 21 | Viewed by 6595
Abstract
This paper proposes a novel robotic animal herding system based on a network of autonomous barking drones. The objective of such a system is to replace traditional herding methods (e.g., dogs) so that a large number (e.g., thousands) of farm animals such as [...] Read more.
This paper proposes a novel robotic animal herding system based on a network of autonomous barking drones. The objective of such a system is to replace traditional herding methods (e.g., dogs) so that a large number (e.g., thousands) of farm animals such as sheep can be quickly collected from a sparse status and then driven to a designated location (e.g., a sheepfold). In this paper, we particularly focus on the motion control of the barking drones. To this end, a computationally efficient sliding mode based control algorithm is developed, which navigates the drones to track the moving boundary of the animals’ footprint and enables the drones to avoid collisions with others. Extensive computer simulations, where the dynamics of the animals follow Reynolds’ rules, show the effectiveness of the proposed approach. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

18 pages, 2256 KiB  
Article
GPS-Spoofing Attack Detection Technology for UAVs Based on Kullback–Leibler Divergence
by Elena Basan, Alexandr Basan, Alexey Nekrasov, Colin Fidge, Nikita Sushkin and Olga Peskova
Drones 2022, 6(1), 8; https://doi.org/10.3390/drones6010008 - 29 Dec 2021
Cited by 22 | Viewed by 7181
Abstract
Here, we developed a method for detecting cyber security attacks aimed at spoofing the Global Positioning System (GPS) signal of an Unmanned Aerial Vehicle (UAV). Most methods for detecting UAV anomalies indicative of an attack use machine learning or other such methods that [...] Read more.
Here, we developed a method for detecting cyber security attacks aimed at spoofing the Global Positioning System (GPS) signal of an Unmanned Aerial Vehicle (UAV). Most methods for detecting UAV anomalies indicative of an attack use machine learning or other such methods that compare normal behavior with abnormal behavior. Such approaches require large amounts of data and significant “training” time to prepare and implement the system. Instead, we consider a new approach based on other mathematical methods for detecting UAV anomalies without the need to first collect a large amount of data and describe normal behavior patterns. Doing so can simplify the process of creating an anomaly detection system, which can further facilitate easier implementation of intrusion detection systems in UAVs. This article presents issues related to ensuring the information security of UAVs. Development of the GPS spoofing detection method for UAVs is then described, based on a preliminary study that made it possible to form a mathematical apparatus for solving the problem. We then explain the necessary analysis of parameters and methods of data normalization, and the analysis of the Kullback—Leibler divergence measure needed to detect anomalies in UAV systems. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

16 pages, 1297 KiB  
Article
Using Ground-Based Passive Reflectors for Improving UAV Landing
by Dmitry Yasentsev, Timofey Shevgunov, Evgeny Efimov and Boris Tatarskiy
Drones 2021, 5(4), 137; https://doi.org/10.3390/drones5040137 - 19 Nov 2021
Cited by 13 | Viewed by 3320
Abstract
The article reviews the problem of landing on hard-to-reach and poorly developed territories, especially in the case of unmanned aerial vehicles. Various landing systems and approaches are analyzed, and their key advantages and disadvantages are summarized; afterwards, an approach with passive reflectors is [...] Read more.
The article reviews the problem of landing on hard-to-reach and poorly developed territories, especially in the case of unmanned aerial vehicles. Various landing systems and approaches are analyzed, and their key advantages and disadvantages are summarized; afterwards, an approach with passive reflectors is considered. A formal definition is provided for the main factors relative to the accuracy analysis, and a model is presented. The way to improve the landing procedure, while simultaneously meeting various practical constraints, is analyzed; the results of numerical simulation are presented, followed by the detailed conclusion describing still remaining challenges and subjects for further research. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

20 pages, 2510 KiB  
Article
A 3D Vision Cone Based Method for Collision Free Navigation of a Quadcopter UAV among Moving Obstacles
by Zhenxing Ming and Hailong Huang
Drones 2021, 5(4), 134; https://doi.org/10.3390/drones5040134 - 12 Nov 2021
Cited by 9 | Viewed by 4113
Abstract
In the near future, it’s expected that unmanned aerial vehicles (UAVs) will become ubiquitous surrogates for human-crewed vehicles in the field of border patrol, package delivery, etc. Therefore, many three-dimensional (3D) navigation algorithms based on different techniques, e.g., model predictive control (MPC)-based, navigation [...] Read more.
In the near future, it’s expected that unmanned aerial vehicles (UAVs) will become ubiquitous surrogates for human-crewed vehicles in the field of border patrol, package delivery, etc. Therefore, many three-dimensional (3D) navigation algorithms based on different techniques, e.g., model predictive control (MPC)-based, navigation potential field-based, sliding mode control-based, and reinforcement learning-based, have been extensively studied in recent years to help achieve collision-free navigation. The vast majority of the 3D navigation algorithms perform well when obstacles are sparsely spaced, but fail when facing crowd-spaced obstacles, which causes a potential threat to UAV operations. In this paper, a 3D vision cone-based reactive navigation algorithm is proposed to enable small quadcopter UAVs to seek a path through crowd-spaced 3D obstacles to the destination without collisions. The proposed algorithm is simulated in MATLAB with different 3D obstacles settings to demonstrate its feasibility and compared with the other two existing 3D navigation algorithms to exhibit its superiority. Furthermore, a modified version of the proposed algorithm is also introduced and compared with the initially proposed algorithm to lay the foundation for future work. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

18 pages, 2192 KiB  
Article
Multiloop Multirate Continuous-Discrete Drone Stabilization System: An Equivalent Single-Rate Model
by Vadim Kramar, Aleksey Kabanov and Vasiliy Alchakov
Drones 2021, 5(4), 129; https://doi.org/10.3390/drones5040129 - 01 Nov 2021
Cited by 1 | Viewed by 2414
Abstract
The article discusses the UAV lateral motion stabilization system, as a MIMO multiloop multirate continuous-discrete system, specified in the form of an input–output model in the domain of discrete Laplace transform or in the form of a structural diagram. Approaches to the construction [...] Read more.
The article discusses the UAV lateral motion stabilization system, as a MIMO multiloop multirate continuous-discrete system, specified in the form of an input–output model in the domain of discrete Laplace transform or in the form of a structural diagram. Approaches to the construction of equivalent T and NT single-rate models for MIMO multiloop multirate continuous-discrete systems are considered. Here, T is the largest common divisor of the sampling periods of the system, N is a natural number that is the smallest common multiple of the numbers characterizing the sampling periods of the system. The resulting impulse representations of the outputs of equivalent models are in the form of rational functions. The basis for the construction of these models is a matrix of sampling densities—a structural invariant of sampling chains. An example of the construction of the indicated matrix and an equivalent single-rate model are given. Obtaining equivalent single-rate models for MIMO multiloop multirate systems allows us to extend the methods of research and synthesis of MIMO continuous and continuous-discrete systems to a common theoretical base—the theory of polynomials and rational functions, which are typical elements of the description of these classes of systems. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

35 pages, 7228 KiB  
Article
Computationally-Efficient Distributed Algorithms of Navigation of Teams of Autonomous UAVs for 3D Coverage and Flocking
by Taha Elmokadem and Andrey V. Savkin
Drones 2021, 5(4), 124; https://doi.org/10.3390/drones5040124 - 25 Oct 2021
Cited by 10 | Viewed by 3300
Abstract
This paper proposes novel distributed control methods to address coverage and flocking problems in three-dimensional (3D) environments using multiple unmanned aerial vehicles (UAVs). Two classes of coverage problems are considered in this work, namely barrier and sweep problems. Additionally, the approach is also [...] Read more.
This paper proposes novel distributed control methods to address coverage and flocking problems in three-dimensional (3D) environments using multiple unmanned aerial vehicles (UAVs). Two classes of coverage problems are considered in this work, namely barrier and sweep problems. Additionally, the approach is also applied to general 3D flocking problems for advanced swarm behavior. The proposed control strategies adopt a region-based control approach based on Voronoi partitions to ensure collision-free self-deployment and coordinated movement of all vehicles within a 3D region. It provides robustness for the multi-vehicle system against vehicles’ failure. It is also computationally-efficient to ensure scalability, and it handles obstacle avoidance on a higher level to avoid conflicts in control with the inter-vehicle collision avoidance objective. The problem formulation is rather general considering mobile robots navigating in 3D spaces, which makes the proposed approach applicable to different UAV types and autonomous underwater vehicles (AUVs). However, implementation details have also been shown considering quadrotor-type UAVs for an example application in precision agriculture. Validation of the proposed methods have been performed using several simulations considering different simulation platforms such as MATLAB and Gazebo. Software-in-the-loop simulations were carried out to asses the real-time computational performance of the methods showing the actual implementation with quadrotors using C++ and the Robot Operating System (ROS) framework. Good results were obtained validating the performance of the suggested methods for coverage and flocking scenarios in 3D using systems with different sizes up to 100 vehicles. Some scenarios considering obstacle avoidance and robustness against vehicles’ failure were also used. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

22 pages, 5905 KiB  
Article
Nonlinear Analysis and Bifurcation Characteristics of Whirl Flutter in Unmanned Aerial Systems
by Anthony Quintana, Rui Vasconcellos, Glen Throneberry and Abdessattar Abdelkefi
Drones 2021, 5(4), 122; https://doi.org/10.3390/drones5040122 - 21 Oct 2021
Cited by 7 | Viewed by 2745
Abstract
Aerial drones have improved significantly over the recent decades with stronger and smaller motors, more powerful propellers, and overall optimization of systems. These improvements have consequently increased top speeds and improved a variety of performance aspects, along with introducing new structural challenges, such [...] Read more.
Aerial drones have improved significantly over the recent decades with stronger and smaller motors, more powerful propellers, and overall optimization of systems. These improvements have consequently increased top speeds and improved a variety of performance aspects, along with introducing new structural challenges, such as whirl flutter. Whirl flutter is an aeroelastic instability that can be affected by structural or aerodynamic nonlinearities. This instability may affect the prediction of potentially dangerous behaviors. In this work, a nonlinear reduced-order model for a nacelle-rotor system, considering quasi-steady aerodynamics, is implemented. First, a parametric study for the linear system is performed to determine the main aerodynamic and structural characteristics that affect the onset of instability. Multiple polynomial nonlinearities in the two degrees of freedom nacelle-rotor model are tested to simulate possible structural nonlinear effects including symmetric cubic hardening nonlinearities for the pitch and yaw degrees of freedom; purely yaw nonlinearity; purely pitch nonlinearity; and a combination of quadratic, cubic, and fifth-order nonlinearities for both degrees of freedom. Results show that the presence of hardening structural nonlinearities introduces limit cycle oscillations to the system in the post-flutter regime. Moreover, it is demonstrated that the inclusion of quadratic nonlinearity introduces asymmetric oscillations and subcritical behavior, where large and potentially dangerous deformations can be reached before the predicted linear flutter speed. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

19 pages, 6983 KiB  
Article
Design and Modeling of an Experimental ROV with Six Degrees of Freedom
by Aleksey Kabanov, Vadim Kramar and Igor Ermakov
Drones 2021, 5(4), 113; https://doi.org/10.3390/drones5040113 - 08 Oct 2021
Cited by 19 | Viewed by 4935
Abstract
With the development of underwater technology, it is important to develop a wide range of autonomous and remotely operated underwater vehicles for various tasks. Depending on the problem that needs to be solved, vehicles will have different designs and dimensions, while the issues [...] Read more.
With the development of underwater technology, it is important to develop a wide range of autonomous and remotely operated underwater vehicles for various tasks. Depending on the problem that needs to be solved, vehicles will have different designs and dimensions, while the issues surrounding reduced costs and increasing the functionality of vehicles are relevant. This article discusses the development of inspection class experimental remotely operated vehicles (ROVs) for performing coastal underwater inspection operations, with a smaller number of thrusters, but having the same functional capabilities in terms of controllability (as vehicles with traditionally-shaped layouts). The proposed design provides controllability of the vehicle in six degrees of freedom, using six thrusters. In classical design vehicles, such controllability is usually achieved using eight thrusters. The proposed design of the ROV is described; the mathematical model, the results of modeling, and experimental tests of the developed ROVs are shown. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

14 pages, 26636 KiB  
Article
Power Line Charging Mechanism for Drones
by Boaz Ben-Moshe
Drones 2021, 5(4), 108; https://doi.org/10.3390/drones5040108 - 01 Oct 2021
Cited by 7 | Viewed by 6084
Abstract
The use of multirotor drones has increased dramatically in the last decade. These days, quadcopters and Vertical Takeoff and Landing (VTOL) drones can be found in many applications such as search and rescue, inspection, commercial photography, intelligence, sports, and recreation. One of the [...] Read more.
The use of multirotor drones has increased dramatically in the last decade. These days, quadcopters and Vertical Takeoff and Landing (VTOL) drones can be found in many applications such as search and rescue, inspection, commercial photography, intelligence, sports, and recreation. One of the major drawbacks of electric multirotor drones is their limited flight time. Commercial drones commonly have about 20–40 min of flight time. The short flight time limits the overall usability of drones in homeland security applications where long-duration performance is required. In this paper, we present a new concept of a “power-line-charging drone”, the idea being to equip existing drones with a robotic mechanism and an onboard charger in order to allow them to land safely on power lines and then charge from the existing 100–250 V AC (50–60 Hz). This research presents several possible conceptual models for power line charging. All suggested solutions were constructed and submitted to a field experiment. Finally, the paper focuses on the optimal solution and presents the performance and possible future development of such power-line-charging drones. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

15 pages, 4412 KiB  
Article
A Monocular Vision Obstacle Avoidance Method Applied to Indoor Tracking Robot
by Shubo Wang, Ling Wang, Xiongkui He and Yi Cao
Drones 2021, 5(4), 105; https://doi.org/10.3390/drones5040105 - 26 Sep 2021
Cited by 5 | Viewed by 2721
Abstract
The overall safety of a building can be effectively evaluated through regular inspection of the indoor walls by unmanned ground vehicles (UGVs). However, when the UGV performs line patrol inspections according to the specified path, it is easy to be affected by obstacles. [...] Read more.
The overall safety of a building can be effectively evaluated through regular inspection of the indoor walls by unmanned ground vehicles (UGVs). However, when the UGV performs line patrol inspections according to the specified path, it is easy to be affected by obstacles. This paper presents an obstacle avoidance strategy for unmanned ground vehicles in indoor environments. The proposed method is based on monocular vision. Through the obtained environmental information in front of the unmanned vehicle, the obstacle orientation is determined, and the moving direction and speed of the mobile robot are determined based on the neural network output and confidence. This paper also innovatively adopts the method of collecting indoor environment images based on camera array and realizes the automatic classification of data sets by arranging cameras with different directions and focal lengths. In the training of a transfer neural network, aiming at the problem that it is difficult to set the learning rate factor of the new layer, the improved bat algorithm is used to find the optimal learning rate factor on a small sample data set. The simulation results show that the accuracy can reach 94.84%. Single-frame evaluation and continuous obstacle avoidance evaluation are used to verify the effectiveness of the obstacle avoidance algorithm. The experimental results show that an unmanned wheeled robot with a bionic transfer-convolution neural network as the control command output can realize autonomous obstacle avoidance in complex indoor scenes. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

33 pages, 40870 KiB  
Article
Precision Landing for Low-Maintenance Remote Operations with UAVs
by Miguel Moreira, Fábio Azevedo, André Ferreira, Dário Pedro, João Matos-Carvalho, Álvaro Ramos, Rui Loureiro and Luís Campos
Drones 2021, 5(4), 103; https://doi.org/10.3390/drones5040103 - 24 Sep 2021
Cited by 4 | Viewed by 4776
Abstract
This work proposes a fully integrated ecosystem composed of three main components with a complex goal: to implement an autonomous system with a UAV requiring little to no maintenance and capable of flying autonomously. For this goal, was developed an autonomous UAV, an [...] Read more.
This work proposes a fully integrated ecosystem composed of three main components with a complex goal: to implement an autonomous system with a UAV requiring little to no maintenance and capable of flying autonomously. For this goal, was developed an autonomous UAV, an online platform capable of its management and a landing platform to enclose and charge the UAV after flights. Furthermore, a precision landing algorithm ensures no need for human intervention for long-term operations. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

24 pages, 2861 KiB  
Article
Terminal Impact Time Control Cooperative Guidance Law for UAVs under Time-Varying Velocity
by Zhanyuan Jiang, Jianquan Ge, Qiangqiang Xu and Tao Yang
Drones 2021, 5(3), 100; https://doi.org/10.3390/drones5030100 - 17 Sep 2021
Cited by 1 | Viewed by 2305
Abstract
Aiming at the problem that multiple Unmanned Aerial Vehicles (UAVs) attack the stationary target cooperatively under time-varying velocity, the cooperative guidance law with finite time convergence on two-dimensional plan and the three-dimensional cooperative guidance laws with impact time constraint are designed separately in [...] Read more.
Aiming at the problem that multiple Unmanned Aerial Vehicles (UAVs) attack the stationary target cooperatively under time-varying velocity, the cooperative guidance law with finite time convergence on two-dimensional plan and the three-dimensional cooperative guidance laws with impact time constraint are designed separately in this paper. Firstly, based on the relative motion equation between UAV and target on two-dimensional plane, the time cooperative guidance model of multiple UAVs is established. Then based on the consistency theory and graph theory, a distributed time cooperative guidance law is designed, which can ensure that the impact time of all UAVs can be quickly consistent in a limited time. Next, the cooperative guidance problem is expanded from two-dimensional plane to three-dimensional space, the motion model between UAV and target in three-dimensional space is established and the expression of time-to-go estimation under time-varying velocity is derived. Finally, according to whether there is the communication among UAVs under the condition of time-varying velocity, a multiple UAVs three-dimensional cooperative guidance law based on desired impact time and a multiple UAVs three-dimensional cooperative guidance law based on coordination variables are designed, respectively. The simulation results show that the cooperative guidance law with finite time convergence on two-dimensional plan and the three-dimensional cooperative guidance law with impact time constraint proposed in this paper are effective, which can both realize the saturation attack under the time-varying velocity. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

21 pages, 9154 KiB  
Article
Automated Drone Detection Using YOLOv4
by Subroto Singha and Burchan Aydin
Drones 2021, 5(3), 95; https://doi.org/10.3390/drones5030095 - 11 Sep 2021
Cited by 49 | Viewed by 13462
Abstract
Drones are increasing in popularity and are reaching the public faster than ever before. Consequently, the chances of a drone being misused are multiplying. Automated drone detection is necessary to prevent unauthorized and unwanted drone interventions. In this research, we designed an automated [...] Read more.
Drones are increasing in popularity and are reaching the public faster than ever before. Consequently, the chances of a drone being misused are multiplying. Automated drone detection is necessary to prevent unauthorized and unwanted drone interventions. In this research, we designed an automated drone detection system using YOLOv4. The model was trained using drone and bird datasets. We then evaluated the trained YOLOv4 model on the testing dataset, using mean average precision (mAP), frames per second (FPS), precision, recall, and F1-score as evaluation parameters. We next collected our own two types of drone videos, performed drone detections, and calculated the FPS to identify the speed of detection at three altitudes. Our methodology showed better performance than what has been found in previous similar studies, achieving a mAP of 74.36%, precision of 0.95, recall of 0.68, and F1-score of 0.79. For video detection, we achieved an FPS of 20.5 on the DJI Phantom III and an FPS of 19.0 on the DJI Mavic Pro. Full article
(This article belongs to the Special Issue Conceptual Design, Modeling, and Control Strategies of Drones)
Show Figures

Figure 1

Back to TopTop