Quadrotor Helicopter Research Articles

Construction of Power Line Inspection System Using a Quadrotor Helicopter

This work presents a construction of a novel system for autonomous inspection of power transmission lines using a quadrotor helicopter. The aircraft follows the power lines at a constant distance and acquires high‐resolution images of the conductors, dampers, and towers. Monitoring of the vegetation under the power lines is also performed. The traditional inspection is carried out by helicopters equipped with high‐resolution cameras or by direct visual examination by personnel climbing over de‐energized power lines. However, visual inspection is time‐consuming, labor‐intensive, and dangerous, and often, helicopter cameras cannot capture the acute details needed for accurate and comprehensive examinations. This work successfully evaluates a mathematical model for the quadrotor helicopter used in autonomous inspection through simulations and flight experiments. Two control strategies for power line tracking are compared: a classical PID and a fuzzy PD control. Several simulations and experimental results confirm the efficiency of both control laws, but the fuzzy controller performs better under strong wind disturbances. The results of this work will be implemented by an electric power company to inspect electrical transmission facilities regularly. © 2024 The Author(s). IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Optimal control for quadrotors during inspection of power utility assets

Renewable energy and power utilities inspection by autonomous aircraft enables rapid and effective risk-free assessment of the state of systems, and provides a qualitative and accurate assessment of defects and damages. To realize maximum operational benefits of aerial inspections, effective controls for autonomous aircraft must be ensured and the system should be operated in an optimal policy. Hence, the objective of this paper is to consider optimal control strategies for a quadrotor helicopter type UAV. Based on some structural properties of the considered system, in particular the flatness property, we suggest a control strategy that ensures tracking a time parameterized path that connects two given points in the state space while minimizing the energy consumption. The proposed controller enables longer-endurance missions for the quadrotor and effective supervision and inspection of large energy systems and power plants. In this paper the analysis of the control law takes into consideration the highly nonlinear dynamic model of the quadrotor and the electrical actuator model. The current approach in solving the optimal control problem under consideration allows one to eliminate the differential equation and to reformulate the optimal control problem to a nonlinear dynamic programming problem. The approach can make monitoring operations of renewable energy plants by aerial vehicles, more efficient.

Adaptive-Neural Finite-Time Sliding Mode Control for Quadrotor Helicopter Attitude Stabilization in Complex Environments

Adaptive-Neural Finite-Time Sliding Mode Control for Quadrotor Helicopter Attitude Stabilization in Complex Environments

Trajectory tracking control for a quadrotor helicopter in the presence of cyber attacks

In this paper, the secure trajectory tracking issue is investigated for a quadrotor helicopter system with unknown-but-bounded (UBB) noises. It is assumed that the generated reference trajectory is sent to the helicopter via wireless networks which could be vulnerable to malicious attacks. The proposed encoding–decoding approach (EDA) can significantly improve the attack detection rate (DR), which is designed as a monotone and continuous function. Moreover, it is illustrated that both the DR and the tracking error can be affected by the parameter of the EDA. In addition, the zonotopic unknown input observer (ZUIO) is designed to estimate the helicopter’s states, which can be utilized to deal with UBB noises. Then, the gains of both the controller and the ZUIO can be calculated by minimizing the P−radius of the corresponding zonotopes. Finally, numerical examples are provided to demonstrate that the parameter of EDA can increase the DR and decrease the false alarm rate (FAR).

Discrete Integral Optimal Controller for Quadrotor Attitude Stabilization: Experimental Results

The Unmanned Aerial Vehicle (UAV) attitude stabilization problem has been dealt with in many previous works through applying a vast range of philosophies of control strategies. In this paper, a discrete controller based on a Linear Quadratic Regulator (LQR) plus integral action is synthesized to stabilize the attitude and altitude of a quadrotor helicopter. This kind of control strategy allows us to reduce the energy consumption rate, and the desired UAV behavior is properly achieved. Experimental tests are conducted with external disturbances such as crosswinds deliberately added to affect the performance of the aerial vehicle. This provides experimental evidence that the integral part considered in the proposed control strategy contributes to improving the performance of the vehicle under external disturbances. In fact, a comparative analysis of potential and kinetic energy consumption is developed between the Optimal Integral Controller (OIC) and a Proportional Integral Derivative Controller (PID), allowing us to determine the level of improvement of the closed-loop system when the discrete Integral Optimal Controller is applied.

Horizontal Fixed Attitude Flight of Quad Rotor Helicopter with Tilting Rotor

A quad rotor helicopter (QRH), a type of unmanned aerial vehicle (UAV), uses a tilted attitude to generate a horizontal thrust component in the flying direction. In the case of autonomous control, the attitude control system is used to tilt the airframe against disturbances such as crosswinds. Consequently, the flying attitude of a QRH is always inclined. In this study, a tilting mechanism for rotors (TMR) was mounted on a QRH to maintain a horizontal attitude. The TMRs were tilted to generate thrust against disturbances without inclining the airframe. The system was constructed using a QRH and TMRs tilted around only one axis and allocated every 90°. Because the airframe is always horizontal, this system can be used for the precise measurement of landforms and buildings. This paper reports the dynamic modeling of QRH equipped with TMRs and discusses the horizontal constant attitude flight using the proposed system.

Leader-Following Formation Tracking for Multiple Quadrotor Helicopters Over Switching Networks

In this paper, we study the leader-following formation tracking problem for multiple quadrotor helicopters via the distributed observer approach. In contrast with existing results in the literature, our approach offers the following features. First, our results apply to jointly connected switching communication networks, which are more general than static communication networks. Second, our control law is fully distributed in the sense that we do not assume that every vehicle can access the information of the desired formation trajectory. Third, with the virtual leader system being modeled by an exosystem, our control law can accomplish the formation tracking for a large class of leader’s trajectories. Two numerical examples are used to illustrate our design.

LIGHT PAYLOAD QUADCOPTER DESIGN FOR THE TRANSPORTATION OF ESSENTIAL GOODS TO PEOPLE IN SELF-ISOLATION

A quadcopter, also called a quadrotor helicopter or quadrotor is a multirotor helicopter that is lifted and propelled by four rotors. In case of lockdown or self-isolation, companies as well as governments can make use of unmanned aerial vehicles equipped with obstacle detection and collision avoidance technology. It is paramount to understand the importance of flight safety with unmanned aerial vehicles. If rules and restrictions are not followed because the user with the controller made an error or was unconscious, a sophisticated system will detect possible conflict and save the drone before collision. In this paper, a digital model was created using MatLab software, in order to analyze and understand how a quadcopter works in its environment. Using the trajectory tools, a well-defined trajectory is defined for a quadcopter in order to better represent its behavior during a light parcel transport assignment. The results obtained can be used to design a drone for the delivery of small packages containing essential goods for people in self-isolation.

GPS spoofing detection algorithm for quad-rotor helicopter based on speed/height comparison

In order to detect whether the GPS is abnormal in the flight state of small size quad-rotor, a GPS spoofing detection algorithm based on data fusion is proposed. Firstly, the velocity data from the monocular camera is calculated by using the self-velocity measurement algorithm based on the improved pyramid optical flow method. Secondly, the speed and altitude data of the IMU sensor unit of the small size quad-rotor were obtained, exactly the speed data were fused with the velocity data measured by using the optical flow method to obtain the optimal velocity estimation at that time. Finally, the small size quad-rotor GPS sensor data information is obtained, the aircraft speed and altitude data are calculated, and comparing with the data calculated in the previous step, to determine whether the GPS data at this time is abnormal. The experimental results on Anafi show that the present GPS spoofing detection algorithm can quickly detect data anomalies during flight. It can be seen that the present algorithm can provide strong technical support for GPS spoofing detection of quad-rotor.

Attitude and Altitude Control of Quadrotor Carrying a Suspended Payload using Genetic Algorithm

The need for quick airborne transportation is critical, especially in emergencies. Drones with suspended payloads might be used to accomplish quick airborne transportation. Due to the environment or the drone's motion, the slung load may oscillate and lead the drone to fall. The altitude and attitude controls are the backbones of the drone's stability, and they must be adequately designed. Because of their symmetrical and simple structure, quadrotor helicopters are one of the most popular drone classes. In this work, a genetic algorithm with two weighted terms fitness function is used to adjust a Proportional-Integral-Derivative (PID) controller to compensate for the altitude and attitude controllers in a quadrotor drone with a slung load.

Stabilization control of quadrotor helicopter through matching solution by controlled Lagrangian method

AbstractThis paper implements the controlled Lagrangian method on nonlinear quadrotor system with two degrees of underactuation. A Lagrangian system based on virtual angles is developed for the quadrotor. Based on the model, the matching conditions presented by nonlinear partial differential equations are explicitly solved for the nonlinear quadrotor system without decoupling or division. Besides, it is demonstrated that a constant controlled kinetic matrix could be utilized for energy shaping and simplify the matching conditions since gyroscopic force terms are omitted. Smooth state feedback control laws guaranteeing asymptotic stability of quadrotor system are obtained. Stability analysis and range of the control parameters are deduced based on the reshaped closed‐loop energy. Simulation for a quadrotor helicopter shows the feasibility and efficiency of the theoretical results.

Real-Time Improvement of a Trajectory-Tracking Control Based on Super-Twisting Algorithm for a Quadrotor Aircraft

This article addresses the development and experimental validation of a trajectory-tracking control for a miniature autonomous Quadrotor helicopter system (X4-prototype) using a robust algorithm control based on second-order sliding mode technique or also known as super-twisting algorithm in outdoor environments. This nonlinear control strategy guarantees the convergence in finite time to a desired path r(t) in the presence of external disturbances or uncertainties in the model affecting the appropriate behavior of our Quadrotor helicopter. For this purpose, a polynomial smooth curve trajectory is selected as a reference signal where the corresponding derivatives of the function are bounded. Moreover, we consider disturbances due to wind gusts acting on the aerial vehicle, and the reference signal is pre-programmed in an advanced autopilot system. The proposed solution consists of implementing a real-time control law based on super-twisting control using GPS measurements in order to obtain the position in the xy-plane to accomplish the desired trajectory. Simulation and experimental results of trajectory-tracking control are presented to demonstrate the performance and robustness of the proposed nonlinear controller in windy conditions.

On Active Vibration Absorption in Motion Control of a Quadrotor UAV

Conventional dynamic vibration absorbers are physical control devices designed to be coupled to flexible mechanical structures to be protected against undesirable forced vibrations. In this article, an approach to extend the capabilities of forced vibration suppression of the dynamic vibration absorbers into desired motion trajectory tracking control algorithms for a four-rotor unmanned aerial vehicle (UAV) is introduced. Nevertheless, additional physical control devices for mechanical vibration absorption are unnecessary in the proposed motion profile reference tracking control design perspective. A new dynamic control design approach for efficient tracking of desired motion profiles as well as for simultaneous active harmonic vibration absorption for a quadrotor helicopter is then proposed. In contrast to other control design methods, the presented motion tracking control scheme is based on the synthesis of multiple virtual (nonphysical) dynamic vibration absorbers. The mathematical structure of these physical mechanical devices, known as dynamic vibration absorbers, is properly exploited and extended for control synthesis for underactuated multiple-input multiple-output four-rotor nonlinear aerial dynamic systems. In this fashion, additional capabilities of active suppression of vibrating forces and torques can be achieved in specified motion directions on four-rotor helicopters. Moreover, since the dynamic vibration absorbers are designed to be virtual, these can be directly tuned for diverse operating conditions. In the present study, it is thus demonstrated that the mathematical structure of physical mechanical vibration absorbers can be extended for the design of active vibration control schemes for desired motion trajectory tracking tasks on four-rotor aerial vehicles subjected to adverse harmonic disturbances. The effectiveness of the presented novel design perspective of virtual dynamic vibration absorption schemes is proved by analytical and numerical results. Several operating case studies to stress the advantages to extend the undesirable vibration attenuation capabilities of the dynamic vibration absorbers into trajectory tracking control algorithms for nonlinear four-rotor helicopter systems are presented.

Development, Control Adjustment, and Gesture Recognition of a Quadrotor Helicopter

Quadrotor helicopters (quadcopters) have become popular in recent years; because they are simple to operate and steady, they are used in aerial photography, competitive flying, and search-and-rescue missions. In addition, wireless sensors have enabled gesture recognition, and therefore, this study investigated the use of gesture recognition to control a quadcopter. A quadcopter was built using Arduino NANO and MPU-6050 modules, which provided insights into the flight principles of a quadrotor system; furthermore, a proportional integrative derivative controller was modified for steady flight. A Leap Motion device was used to understand the logic behind hand gestures and test the success rate of each gesture, and was then combined with a Parrot AR.Drone 2.0 to achieve gesture recognition controls and uncover problems with connections between hand gestures. These problems were addressed by changing the code in the gesture control program. The results of the completed gesture control experiment demonstrated high gesture recognition performance as well as the ability to meet the requirements for controlling a quadcopter.

Sliding Mode Fault Tolerant Control for a Quadrotor with Varying Load and Actuator Fault

In this paper, an adaptive sliding mode fault-tolerant control scheme based on prescribed performance control and neural networks is developed for an Unmanned Aerial Vehicle (UAV) quadrotor carrying a load to deal with actuator faults. First, a nonsingular fast terminal sliding mode (NFTSM) control strategy is presented. In virtue of the proposed strategy, fast convergence and high robustness can be guaranteed without stimulating chattering. Secondly, to obtain correct fault magnitudes and compensate the failures actively, a radial basis function neural network-based fault estimation scheme is proposed. By combining the proposed fault estimation strategy and the NFTSM controller, an active fault-tolerant control algorithm is established. Then, the uncertainties caused by load variation are explicitly considered and compensated by the presented adaptive laws. Moreover, by synthesizing the proposed sliding mode control and prescribed performance control (PPC), an output error transformation is defined to deal with state constraints and provide better tracking performance. From the Lyapunov stability analysis, the overall system is proven to be uniformly asymptotically stable. Finally, numerical simulation based on a quadrotor helicopter is carried out to validate the effectiveness and superiority of the proposed algorithm.

Conditional integrator sliding mode control of an unmanned quadrotor helicopter

Sliding mode control (SMC) is a widely used control law for quadrotor regulation and tracking control problems. The purpose of this article is to solve the tracking problem of quadrotors using a relatively novel nonlinear control law based on SMC that makes use of a conditional integrator. It is demonstrated by a motivation example that the proposed control law can improve the transient response and chattering shortcomings of the previous approaches of similar SMC based controllers. The adopted Newton–Euler model of quadrotor dynamics and controller design is treated separately in two subsystems: attitude and position control loops. The stability of the control technique is demonstrated by Lyapunov’s analysis and the effectiveness and performance of the proposed method are compared with a similar integral law, also based on SMC, and validated by tracking control problems using numerical simulations. Simulations were developed in the presence of external disturbances in order to evaluate the controller robustness. The effectiveness of the proposed controller was verified by performance indexes, demonstrating less accumulated tracking errors and control activity and improvement in the transient response and disturbance rejection when compared to a conventional integrator sliding mode controller.

Finite-time control for quadrotor based on composite barrier Lyapunov function with system state constraints and actuator faults

This study focuses on a finite-time control scheme for a quadrotor helicopter with implicit system state constraints subjected to multiple actuator faults and external multi-source disturbances. The quadrotor trajectory tracking problem, which includes actuator faults, bias faults, and multi-source disturbances, is transformed into an error system stability problem with state constraints. An adaptive law for the efficiency loss factor is designed on the basis of immersion and invariance theory. A finite-time dynamic scale factor is proposed for the first time, and a supervision factor is developed to supervise and regulate it at the upper level. Then, a composite time-varying barrier Lyapunov function (CTV-BLF) based on the sliding mode surface and an adaptive estimation of the upper bound of the multi-source disturbances are implemented. The constructed CTV-BLF can guarantee that the system state constraints will not be violated. A stability analysis of the new proposition proves that the trajectory tracking error is uniformly bounded in finite time. Final simulation results verify the effectiveness of the proposed scheme.

Magnetic interference mapping of four types of unmanned aircraft systems intended for aeromagnetic surveying

Abstract. Magnetic interference source identification is a critical preparation step for magnetometer-mounted unmanned aircraft systems (UAS) used for high-sensitivity geomagnetic surveying. A magnetic field scanner was built for mapping the low-frequency interference that is produced by a UAS. It was used to compare four types of electric-powered UAS capable of carrying an alkali-vapour magnetometer: (1) a single-motor fixed-wing, (2) a single-rotor helicopter, (3) a quad-rotor helicopter, and (4) a hexa-rotor helicopter. The scanner's error was estimated by calculating the root-mean-square deviation of the background total magnetic intensity over the mapping duration; averaged values ranged between 3.1 and 7.4 nT. Each mapping was performed above the UAS with the motor(s) engaged and with the UAS facing in two orthogonal directions; peak interference intensities ranged between 21.4 and 574.2 nT. For each system, the interference is a combination of both ferromagnetic and electrical current sources. Major sources of interference were identified such as servo(s) and the cables carrying direct current between the motor battery and the electronic speed controller. Magnetic intensity profiles were measured at various motor current draws for each UAS, and a change in intensity was observed for currents as low as 1 A.

Quadrotor UAV attitude stabilization using fuzzy robust control

In this paper, a robust controller for attitude stabilization of a small quadrotor helicopter is developed. The TS (Takagi-Sugeno) fuzzy model approach and the [Formula: see text] robust control are combined to produce the proposed algorithm. Besides, disturbances and parametric uncertainties are considered. First, the nonlinear model of the vehicle is linearized around several operating points to obtain the representation of a TS fuzzy model, which represents the nonlinearity of the system dynamics. Then, a robust fuzzy controller is synthesized which guarantees desired control performances. The given controller is designed using numerical tools such as linear matrix inequalities (LMI). Finally, simulation results and real-time experiments are presented to validate the performance of the proposed scheme to robustly stabilize the quadrotor dynamics at the desired reference.

A Robust Fault-Tolerant Control for Quadrotor Helicopters against Sensor Faults and External Disturbances

This paper presents an active fault-tolerant control strategy for quadrotor helicopters to simultaneously accommodate sensor faults and external disturbances. Unlike most of the existing fault diagnosis and fault-tolerant control schemes for quadrotor helicopters, the proposed fault diagnosis scheme is able to estimate sensor faults while eliminating the effect of external disturbances. Moreover, the proposed fault-tolerant control scheme is capable to eliminate the adverse effect of external disturbances as well by designing a disturbance observer to effectively estimate the unknown external disturbances and integrating with the designed integral sliding-mode controller. In this case, the continuous operation of the quadrotor helicopter is ensured while avoiding the unexpected control chattering. In addition, the stability of the closed-loop system is theoretically proved. Finally, the effectiveness and advantages of the proposed scheme are validated and demonstrated through comparative numerical simulations of the quadrotor helicopter under different faulty and uncertain scenarios.