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Nowadays, we often hear about autonomous Unmanned Aerial Vehicles because of their growing diffusion and ability to adapt to multiple application contexts. When speaking of UAVs, we refer to a category of small/medium-sized aerial vehicles that can fly autonomously. A category of great interest is that of fixed-wing UAVs, due to its inherent energy...
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This paper compares a conventional interacting multiple model Kalman filter (IMM-KF) filter and an interacting multiple models with maximum correntropy Kalman filter (IMMMCKF). A nonlinear UAV dynamics model was used to compare these two methods. The compared filters estimated the position of the UAV under the noise distribution. Although KF has re...
Focusing on the actuator fault of the quadrotor unmanned aerial vehicle (QUAV), an active fault-tolerant control scheme based on fixed-time linear active disturbance rejection control is proposed. Firstly, in order to simplify the complex dynamic model, the virtual control quantity is introduced to decouple the flight control system of the QUAV. Se...
This paper presents a novel concept of a modular multirotor aerial robotic platform that can be used for specific profiles of heavy payload missions. A comprehensive mathematical model of the multirotor unmanned aerial vehicle (UAV) is presented, which is divided into the dynamic model and the control allocation scheme that describes the configurat...
Tail-sitter unmanned aerial vehicles (UAVs) are promising vertical takeoff and landing (VTOL) UAV suitable for multi-missions but the road to the commercialization of tail-sitter UAVs is tortuous. This paper aims to provide a systematic design methodology and present the development process for a novel biplane quadrotor tail-sitter UAV platform nam...
Tilt-rotor unmanned aerial vehicles (UAV) have gained significant importance in the aeronautical industry due to their ability to transition between vertical and horizontal flight. One of the important steps in the development of such UAVs is to assess their performance and stability characteristics. Simulation of flight dynamics is an essential to...
Citations
... The 6 degrees-of-freedom fixed-wing UAV and wind dynamics have been implemented in a Matlab software-in-theloop UAV platform developed at TU Delft, which replicates the open-source ArduPilot autopilot code (cf. [49] for implementation details and for all the details about the UAV model, which is a based on a Hobby-King Bixler UAV). We take the following environmental conditions: constant wind amplitude is W = 4 m/s with wind angle ψ W = 230 • ; and a Dryden turbulence [9,Sect. ...
The high maneuverability of fixed-wing unmanned aerial vehicles (UAVs) exposes these systems to several dynamical and parametric uncertainties, severely affecting the fidelity of modeling and causing limited guidance autonomy. This article shows enhanced autonomy via adaptation mechanisms embedded in the guidance law: a vector-field method is proposed that does not require a priori knowledge of the UAV course time constant, coupling effects, and wind amplitude/direction. Stability and performance are assessed using the Lyapunov theory. The method is tested on software-in-the loop and hardware-in-the-loop UAV platforms, showing that the proposed guidance law outperforms state-of-the-art guidance controllers and standard vector-field approaches in the presence of significant uncertainty.
... The numerical values of the gains used in each of the five loops for ArduPilot are in Table I. These gains are in line with those presented in [44], which are the result of gains tuned on Bixler UAV, using the AutoTune procedure of ArduPilot [45]. ...
... To make the tests realistic, the ArduPilot functionalities have been emulated in Matlab according to the ArduPilot documentation and code, which allows to perform software-in-the-loop tests. More details on this software-in-the-loop platform, developed and maintained by some of the authors, are in [43], [44]. The simulation environment comprises sensor measurement noises and control deflection limits (aileron: ±30 degrees, elevator: ±15 degrees, rudder: ±25 degrees). ...
... More complete discussions of UAV dynamics can be found in [27,Chap. 3] and a complete list of parameters is in [44]. Figure 6 illustrates the axes of motion of the UAV. ...
This article presents an adaptive method for ArduPilot-based autopilots of fixed-wing unmanned aerial vehicles (UAVs). ArduPilot is a popular open-source unmanned vehicle software suite. We explore how to augment the PID loops embedded inside ArduPilot with a model-free adaptive control method. The adaptive augmentation, adopted for both attitude and total energy control, uses input/output data without requiring an explicit model of the UAV. The augmented architecture is tested in a software-in-the-loop UAV platform in the presence of several uncertainties (unmodeled low-level dynamics, different payloads, time-varying wind, and changing mass). The performance is measured in terms of tracking errors and control efforts of the attitude and total energy control loops. Extensive experiments with the original ArduPilot, the proposed augmentation, and alternative autopilot strategies show that the augmentation can significantly improve the performance for all payloads and wind conditions: the UAV is less affected by wind and exhibits more than 70% improved tracking, with more than 7% reduced control effort.
... where V out is the air velocity at the exit of the propeller and P 0 the atmospheric pressure. In [41], [42], it is shown that V out can be approximated as R(k mot δ t +q mot ), where R is the radius of the propeller, and the other term is its angular velocity, approximated as a linear function of the throttle δ t (in %). ...
... where b wing is the wingspan, and C Y , C l and C n are nondimensional coefficients depending on side-slip angle β , roll rate p, yaw rate r, aileron deflection δ a and rudder deflection δ r . Estimates of C Y , C l , C n , C L , C D , and C m can obtained for a fixed-wing UAV by means of USAF DATCOM [42], [43] or similar software, after inputting all the geometric characteristics of the UAV. The UAV model described in this section is in line with the literature (cf. ...
... 3 ≜ Ω γ 0 c 31 . Hence, from(42),V ≤ −ΩV when min {||x||, ||ξ ||} ≥ max {ι, ι 0 , ι 1 , ι 2 , ι 3 } ⇒ ||x|| ≥ max {ι, ι 0 , ι 1 , ι 2 , ι 3 } . ...
Effective design of autopilots for fixed-wing unmanned aerial vehicles (UAVs) is still a great challenge, due to unmodeled effects and uncertainties that these vehicles exhibit during flight. Unmodeled effects and uncertainties comprise longitudinal/lateral cross-couplings, as well as poor knowledge of equilibrium points (trimming points) of the UAV dynamics. The main contribution of this article is a new adaptive autopilot design, based on uncertain Euler–Lagrange dynamics of the UAV and where the control can explicitly take into account under-actuation in the dynamics, reduced structural knowledge of cross-couplings and trimming points. This system uncertainty is handled via appropriately designed adaptive laws: stability of the controlled UAV is analyzed. Hardware-in-the-loop tests, comparisons with an Ardupilot autopilot and with a robustified autopilot validate the effectiveness of the control design, even in the presence of strong saturation of the UAV actuators.
... This design characteristics have high inertial and loading forces which help the UAV more efficient in flight, (Johnson Okoduwa Imumbhon, (2021) [2]. In recent years, researchers are quite enthusiastic in designing and developing new aged UAV's such as a cyclo-copter with horizontal rotary wing design which is a modified model which takes the reference of Voith Schneider also called cycloidal drive propulsion system, the horizontal propulsion of cyclo-copter comes under the vertical take-off and landing aircraft models [VTOL], the research is been conducted by (Brian Davis et.al,(2021) [3].The fixed wing type UAV's are robust in structure and can carry payloads in long and medium scale missions, these are generally used for domestic and military purposes and are efficient when compared to other designs (Stefano Fari, (2017) [6]. The conventional drone models with a propeller fan, which runs on lithium batteries are highly used for surveillance purpose. ...
Unmanned Aerial Vehicle is one of many types of aircraft that growing rapidly these days for many uses from farm usage, military usage, and many more. To develop aviation technology, research is done to find a perfect winglet geometry for the airfoil NACA 4412 that used generally. Research is done with Computational Fluid Dynamics method, with ANSYS Fluent to find lift force, drag force and lift-to-drag ratio. The results will be plotted in Microsoft Excel. From this research, it is shown that the usage of a correct winglet will improve wing performance. The usage of a blended winglet has the highest value of lift-to-drag ratio, with improved performance, but it has less stability compared with curved winglet. For now, blended winglet is the best winglet for airfoil NACA 4412. It can increase the average performance by 2%-3%.
... To address realistic problems such as unmodelled dynamics, sensor noise etc., the experiments make use of a software-inthe-loop UAV model developed in the past by some of the authors [22], [53]. This UAV model includes the low-level autopilot of a UAV (ArduPilot) and can capture unmodelled lowlevel dynamics and sensor noise. ...
This article presents a new adaptive method for formation control of unmanned aerial vehicles (UAVs) with limited leader information and communication. We study a formation control protocol in the framework of vector-field guidance where the leader can communicate its position and orientation but not its velocity. A practical motivation for this scenario is the so-called congestion-aware control, in which tradeoffs between the density of unmanned vehicles and communication interference caused by many communicating vehicles arise: these tradeoffs may require to reduce the communication load to avoid interference. To compensate for the lack of knowledge of the leader velocity, each UAV makes use of a local estimation mechanism. The resulting method is an adaptive control method, whose stability can be established using Lyapunov stability. We show that the method can be extended to a distributed communication setting with a few neighboring UAVs in place of the leader. Extensive simulations with different formation shapes (Y, V, and T formation) show that the proposed adaptation mechanism effectively achieves the formation despite the unknown leader velocity. The proposed mechanism has a very similar performance to the ideal case when the leader velocity is perfectly known, and outperforms all the nonadaptive cases in which the followers have an incorrect knowledge of the leader velocity.
... The UAV is modeled using 6 degrees-of-freedom equations of motions. Due to space limits, only the main equations are recalled, and details can be found in [4], [30]. ...
... The fixed-wing UAV and wind dynamics have been implemented in the Matlab-Simulink environment by means of the Aerospace blockset [28]. Some screen-shots from the simulator can be seen in Fig. 2 and Fig. 3. ...
This paper discusses the design and software-in-the-loop implementation of adaptive formation controllers for fixed-wing unmanned aerial vehicles (UAVs) with parametric uncertainty in their structure, namely uncertain mass and inertia. In fact, when aiming at autonomous flight, such parameters cannot assumed to be known as they might vary during the mission (e.g. depending on the payload). Modeling and autopilot design for such autonomous fixed-wing UAVs are presented. The modeling is implemented in Matlab, while the autopilot is based on ArduPilot, a popular open-source autopilot suite. Specifically, the ArduPilot functionalities are emulated in Matlab according to the Ardupilot documentation and code, which allows us to perform software-in-the-loop simulations of teams of UAVs embedded with actual autopilot protocols. An overview of realtime path planning, trajectory tracking and formation control resulting from the proposed platform is given. The software-in-the-loop simulations show the capability of achieving different UAV formations while handling uncertain mass and inertia.
... for appropriate constants a φ1 , a φ2 , where δ a is the aileron command andd φ andd χ are disturbances coming from crosseffects of neglected dynamics. Let us focus only on the lateral dynamics, most relevant to path following; details on the longitudinal UAV control loop can be found in [30]. ...
The actual performance of model-based path-following methods for Unmanned Aerial Vehicles (UAVs) show considerable dependence on the wind knowledge and on the fidelity of the dynamic model used for design. This work analyzes and demonstrates the performance of an adaptive Vector Field (VF) control law which can compensate for the lack of knowledge of the wind vector and for the presence of unmodelled course angle dynamics. Extensive simulation experiments, calibrated on a commercial fixed-wing UAV and proven to be realistic, show that the new VF method can better cope with uncertainties than its standard version. In fact, while the standard VF approach works perfectly for ideal first-order course angle dynamics (and perfect knowledge of the wind vector), its performance degrades in the presence of unknown wind or unmodelled course angle dynamics. On the other hand, the estimation mechanism of the proposed adaptive VF effectively compensates for wind uncertainty and unmodelled dynamics, sensibly reducing the path-following error as compared to the standard VF.
