Mathematical Model for Studying the Evolution of Multi-Role Unmanned Aerial Vehicle in Turbulent Atmosphere

2013 ◽  
Vol 325-326 ◽  
pp. 984-989
Author(s):  
Cristina Mihailescu ◽  
Ioan Farcasan

The paper purpose is to present some aspects regarding the control system of unmanned aerial vehicle - UAV, used for local observations, surveillance and monitoring of interest area or as a training target for anti-aircraft systems. The calculus methodology allows a numerical simulation of UAV evolution in bad atmospheric conditions by using a nonlinear model, as well as a linear one for obtaining the guidance command. The UAV model which will be presented has six DOF (degrees of freedom), and an autonomous control system. This theoretical development allows us to build the stability matrix, command matrix and the control matrix and finally to analyze the stability of autonomous UAV flight. A robust guidance system, based on Kalman filter will be evaluated for different fly conditions and the results will be presented. The flight parameters and guidance will be analyzed. The paper is inspired by national project SAMO (Autonomous Aerial Monitoring System for Interest Areas of Great Endurance). Keywords: UAV, Simulation, Control, Guidance, Endurance, Surveillance, Monitoring, Kalman filter

2018 ◽  
Vol 7 (2.3) ◽  
pp. 18
Author(s):  
Mishell D. Lawas ◽  
Sherwin A. Guirnaldo

The stability of an Unmanned Aerial Vehicle (UAV) during actual flight conditions is one parameter that is very important in systems design in Avionics. In this research, two sensors, the autopilot microcontroller and the smartphone gyroscope sensing mechanism, are fused together and calibrated to monitor the flying behavior of the UAV prior to actual test flights. The two fused sensors and installed inside the UAV for relatively increased sensing accuracy and best flight monitoring capabilities. A Kalman filter is used as fusion technique and a Stewart Motion tracker is also used to test the ruggedness and accuracy of the fused sensor system. Experiment results show that fused system can give an overall mean square error or 1.9729.


Author(s):  
Mehmet Gokberk Patan ◽  
Fikret Caliskan

This article handles the issue of fault-tolerant control of a quadrotor unmanned aerial vehicle (UAV) in the existence of sensor faults. A general non-linear model of the quadrotor is presented. Several non-linear Kalman filters namely, the extended Kalman filter, the unscented Kalman filter and the cubature Kalman filter (CKF) are utilized to estimate the states of the quadrotor and to compare the estimation performances. Some flight scenarios are simulated, and the simulation results show that the CKF has the smallest estimation error as expected in theory. Control of the quadrotor heavily depends on the measured values received from sensors. Therefore, the control system requires fault-free sensors. However, small quadrotors and UAVs are mostly equipped with low-cost and low-quality sensors, and hence, they may fail to indicate correct measurement values. If the sensors are faulty, then the control system itself should be actively tolerant to sensor faults. Measurements of these kinds of sensors suffer from bias and external noise due to temperature variations, vibration and other external conditions. Since the bias is one of the very common faults in these sensors, a sensor bias is taken into consideration as a fault and occurs abruptly at a certain time and continues throughout the considered scenarios. By using the residual signals generated by the non-linear filters, sensor faults are detected and isolated. Then, two different methods are proposed for removing the effects of faults and achieving active fault–tolerant control. The effectiveness of the presented two techniques is shown in the simulations.


2020 ◽  
Vol 4 (157) ◽  
pp. 178-183
Author(s):  
L. Romaniuk ◽  
I. Chykhira

Purpose. The aim of the article is to reveal the mechanism of formation of safe UAV movement in the conditions of radio attacks. Methodology. Scientists from Ternopil National Technical University named after Ivan Pulyuy have consistently developed and studied several mechanisms for the formation of safe movement of unmanned aerial vehicles in radio attacks in order to create a perfect model with which to launch UAVs in areas with high radio attack. As a result of previous work, the mechanism of formation of safe movement of UAVs in the conditions of radio attacks based on methods of increasing the stability of providing information about the route of the unmanned aerial vehicle in the use of REP and air defense systems. Results. The article reveals the mechanism of formation of safe movement of unmanned aerial vehicle in the conditions of radio attacks. Analysis of known solutions in the field of increasing the stability of the control path of unmanned aerial vehicles and electronic suppression demonstrated the relevance of the problem of forming flight routes of unmanned aerial vehicles bypassing opposing enemy areas, taking into account the use of air defense and electronic warfare. The authors emphasize that most drone control tasks are now automated due to their high complexity and versatility. An automated control system operating under the control of a human operator is used as a control factor on an unmanned aircraft. It is emphasized that the main threats to unmanned aerial vehicles in modern conditions are the possibility of their destruction by air defense systems, as well as disruption of the radio communication and control system between the control center and the UAV by electronic suppression. The need for constant tracking of UAV flight by transmitting commands from the launcher is revealed. It is also emphasized the low level of automation of the onboard control system of the unmanned aerial vehicle and the inability to make adequate decisions on information received from onboard sensors in complex situations that require constant monitoring of UAV flight by a human operator. Scientific novelty. For the first time the functional scheme of the UAV recognition mechanism in the conditions of radio attacks is developed and the mechanism of formation of safe movement of the UAV in the conditions of radio attacks which is based on three basic techniques is defined. The first method is the method of clustering the flight zones of an unmanned aerial vehicle according to the degree of control stability. Based on the second method, the authors propose a method of forming the routes of UAV flights, taking into account the location of air defense and electronic warfare. The last link is the method of assessing the stability of providing information about the route of the unmanned aerial vehicle in terms of the use of air defense and electronic warfare. Practical relevance. The results of the work can be implemented in the process of forming the safe movement of UAVs in the conditions of radio attacks. Keywords: unmanned aerial vehicle; air traffic control; space; security; flight.


2020 ◽  
Vol 1 (1) ◽  
pp. 22-27
Author(s):  
S. LYSENKO ◽  

The paper presents an intellectualized control system for unmanned aerial vehicles. It is based on the use of the fuzzy logic, implementation of which in the Controller of the unmanned aerial device allowed to track and control the trajectory of its movement. The experimental researches prove the efficiency of the device application of fuzzy logic for control of the drone in conditions of external influences implementation. To construct an intellectualized control system of unmanned aerial vehicles, their structure was considered. The base of the system is used for quadunmanned aerial vehicle, which includes four screws, located symmetrically around the central building. The peculiarity of the drone is that its adjacent screws must spin the opposite one from each other. This requirement is explained by the need to prevent system rotation around its own central axis. Depending on the required trajectory, an important aspect was the ability to set different values of the power of the drone engines. Despite the fact that the simplicity of its structure are characterized, they are able to implement a large set of motion models together with a demonstration of high maneuverability. It is reached the presence of six degrees of freedom, which consist of three progressive and three rotating components to set the trajectory of a movement. In order to solve this problem, it was possible to solve the apparatus of fuzzy logic as the basis of the mathematical model of the system. This allowed to ensure a vague logical control of the fog, and, in turn, intellectualize the behavior of drone in the air in the conditions of external influences on the change of a predetermined trajectory of its movement. At the heart of the Intellectualized unmanned Aerial vehicle control system, two fuzzy controllers were involved in the production of control signals for the command of a UAV flight height and an angle of inclination.


2021 ◽  
Vol 24 (4) ◽  
pp. 200-216
Author(s):  
V. V. Nguyen ◽  
E. E. Usina

Purpose or research. Improving guidance accuracy of robotic capture mounted on an unmanned aerial vehicle and the stability of combined aerial manipulation system is the main objective of this study. In order to achieve this goal, a particular task of developing a manipulator control system that considers joint working space of manipulator and unmanned aerial vehicle has been solved. Methods. Kinematic model of a manipulator with three degrees of freedom is proposed in this work. This is a part of air manipulation system of quadrotor. Rotary movement of two successive links is performed by means of hinge joint. Direct and inverse kinematic tasks were solved for this manipulator. Equations for dynamic model were also obtained. Dynamic response of each link is sufficient for quick stabilization of the system with little re-adjustment. Self-tuning fuzzy proportional-integral-differentiating (PID) regulator was developed based on these data to control the manipulator. Control system for each manipulator link consists of a PID regulator and a fuzzy PID output using Mamdani method. Results. Simulation of developed manipulator control system was carried out in the absence of disturbances. The proposed control system satisfies specified requirements and ensures continuous and smooth movement of manipulator links in calculated trajectory. Conclusion. The developed three-link manipulator motion control method provides a horizontal mass center shift not more than 1.25 mm, which is an acceptable result for rapid stabilization of unmanned aerial manipulator and further practical experiments.


2016 ◽  
Vol 39 (3) ◽  
pp. 267-276 ◽  
Author(s):  
Burak Yuksek ◽  
N Kemal Ure ◽  
Fikret Caliskan ◽  
Gokhan Inalhan

In this study, a fault tolerant heading control system is designed for a one-third scale fixed wing vertical takeoff-and-landing unmanned aerial vehicle, Turac. A nonlinear six degrees-of-freedom (DoF) mathematical model is obtained and linearized at the calculated trim flight condition. A proportional heading control system is designed as a nominal horizontal flight controller. Detection and isolation of the faults that can occur during flight are performed by Kalman filters which are designed individually for each sensor output. After the fault isolation process the obtained fault data is fed to the reconfigurable Kalman filter. Then the feedback signal from the faulty sensor is blocked and the estimated output from the reconfigurable Kalman filter is fed to the control system. So, the closed-loop system could follow the reference signal without updating the controller’s parameters. Simulation studies are performed on the closed-loop system for faulty sensor situations.


Author(s):  
Hongbo Xin ◽  
Yujie Wang ◽  
Xianzhong Gao ◽  
Qingyang Chen ◽  
Bingjie Zhu ◽  
...  

The tail-sitter unmanned aerial vehicles have the advantages of multi-rotors and fixed-wing aircrafts, such as vertical takeoff and landing, long endurance and high-speed cruise. These make the tail-sitter unmanned aerial vehicle capable for special tasks in complex environments. In this article, we present the modeling and the control system design for a quadrotor tail-sitter unmanned aerial vehicle whose main structure consists of a traditional quadrotor with four wings fixed on the four rotor arms. The key point of the control system is the transition process between hover flight mode and level flight mode. However, the normal Euler angle representation cannot tackle both of the hover and level flight modes because of the singularity when pitch angle tends to [Formula: see text]. The dual-Euler method using two Euler-angle representations in two body-fixed coordinate frames is presented to couple with this problem, which gives continuous attitude representation throughout the whole flight envelope. The control system is divided into hover and level controllers to adapt to the two different flight modes. The nonlinear dynamic inverse method is employed to realize fuselage rotation and attitude stabilization. In guidance control, the vector field method is used in level flight guidance logic, and the quadrotor guidance method is used in hover flight mode. The framework of the whole system is established by MATLAB and Simulink, and the effectiveness of the guidance and control algorithms are verified by simulation. Finally, the flight test of the prototype shows the feasibility of the whole system.


2016 ◽  
Vol 817 ◽  
pp. 150-161 ◽  
Author(s):  
Marcin Szuster ◽  
Piotr Gierlak

The article focuses on the implementation of the globalized dual-heuristic dynamic programming algorithm in the discrete tracking control system of the three degrees of freedom robotic manipulator. The globalized dual-heuristic dynamic programming algorithm is included in the approximate dynamic programming algorithms family, that bases on the Bellman’s dynamic programming idea. These algorithms generally consist of the actor and the critic structures realized in a form of artificial neural networks. Moreover, the control system includes the PD controller, the supervisory term and an additional control signal. The structure of the supervisory term derives from the stability analysis, which was realized using the Lyapunov stability theorem. The control system works on-line and the neural networks’ weight adaptation process is realized in every iteration step. A series of computer simulations was realized in Matlab/Simulink software to confirm performance of the control system.


2021 ◽  
Author(s):  
Shin-Ichiro Higashino ◽  
Masahiko Hayashi ◽  
Takuya Okada ◽  
Shuji Nagasaki ◽  
Koichi Shiraishi ◽  
...  

Abstract. The authors have developed a system for the Antarctic stratospheric aerosol observation and sample-return using the combination of a rubber balloon, a parachute, and a gliding fixed-wing unmanned aerial vehicle (UAV). A rubber balloon can usually reach 20 km to 30 km in altitude, but it becomes difficult for the UAV designed as a low-subsonic UAV to directly glide back from the stratospheric altitudes because the quantitative aerodynamic characteristics necessary for the control system design at such altitudes are difficult to obtain. In order to make the observation and sample-return possible at such higher altitudes while avoiding the problem with the control system of the UAV, the method using the two-stage separation was developed and attempted in Antarctica. In two-stage separation method, the UAV first descends by a parachute after separating from the balloon at stratospheric altitude to a certain altitude wherein the flight control system of the UAV works properly. Then it secondly separates the parachute for autonomous gliding back to the released point on the ground. The UAV in which an optical particle counter and an airborne aerosol sampler were installed was launched on January 24, 2015 from S17 (69.028S, 40.093E, 607 m MSL) near Syowa Station in Antarctica. The system reached 23 km in altitude and the UAV successfully returned aerosol samples. In this paper, the details of the UAV system using the two-stage separation method including the observation flight results, and the preliminary results of the observation and analyses of the samples are shown.


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