Quadrotor Helicopter Research Articles

Extreme learning machine based actuator fault detection of a quadrotor helicopter

Actuator fault might occur during quadrotor helicopter’s flight. It is a demand to detect actuator fault in real-time. An actuator fault detection method based on extreme learning machine is propos...

Integral backstepping sliding mode control for quadrotor helicopter under external uncertain disturbances

In this paper, a novel nonlinear control strategy along with its simulation for a quadrotor helicopter is proposed. The normal 6-DOF dynamic model of the quadrotor based on the Newton–Euler formula as well as the model with external uncertain disturbances are established. Considering the underactuated and strongly coupled characteristics of quadrotor helicopter, we design a nonlinear control method by using integral backstepping combined with the sliding mode control (integral BS-SMC) to stabilize the quadrotor attitude and to accomplish the task of trajectory tracking. The designed controllers based on the hierarchical control scheme can be divided into rotational controller and translational controller and their stability are validated by the Lyapunov stability theorem. By means of the proposed controllers, the chattering phenomenon and discontinuousness of control inputs faced by traditional sliding mode control (SMC) can be avoided. The feasibility of the control approach presented in this paper is verified by the simulations under different scenarios. The results show that the nonlinear control method not only has a better tracking performance than others but also has a higher robustness when unknown disturbances occur.

Full control of a quadrotor using parameter-scheduled backstepping method: implementation and experimental tests

This paper proposes a nonlinear controller for a quadrotor helicopter, under the control of which the system is globally asymptotically stabilized with good control quality. The proposed controller is synthesized by Command Filtered Backstepping method with a novel parameter scheduling scheme. By scheduling controller parameters within the system-stabilizing region, the convergence speeds of errors in each step are adaptively adjusted based on different flight conditions. Amplitudes of control signals are reduced during fast tracking progress to avoid actuator saturation, which is hardly modeled and may cause instability. The controller also allows more aggressive tuning that achieves better regulation accuracy. The technology to implement the proposed controller is illustrated in detail, and key parameters of quadrotor model and the actuator’s dynamics are identified by experiments. To validate the proposed method, experimental flight tests are conducted under three typical flight conditions. Results comparing to other methods such as PID, sliding mode control and dynamic surface control are demonstrated, showing that the proposed controller is practical to an actual quadrotor system and can achieve good control performance.

Active Fault-Tolerant Control of Unmanned Quadrotor Helicopter Using Linear Parameter Varying Technique

By adopting the linear parameter varying (LPV) control technique, this paper presents an active fault-tolerant control (FTC) strategy with application to unmanned quadrotor helicopter (UQH). Adverse effects from payload grasping and dropping caused variations of system dynamics as well as battery drainage induced loss of actuator effectiveness are expected to be counteracted in this study. First, the UQH is manipulated by a well designed baseline controller. In the presence of either payload grasping/dropping or battery drainage, their magnitudes are then obtained from a LPV-based fault detection and diagnosis (FDD) scheme. Next, based on the estimated values, a fault-tolerant tracking controller, which is linear parameter dependent, is devised in a convex polytopic LPV representation schedules to a new status in corresponding to the system variations, so that the negative impacts can be compensated. The parameters that change with system variations are specified as scheduling scalars for the LPV controller, while the ultimate control rule is obtainable by employing a set of well-established linear matrix inequality (LMI) conditions. Finally, both numerical simulations on a nonlinear model of UQH and experiments on a real UQH are conducted so as to testify the effectiveness of proposed methodology.

Control Strategy for a Quadrotor Helicopter with State Delay via Improved Guaranteed Cost Control and Quantum Adaptive Control

AbstractImproved guaranteed cost control and quantum adaptive control are developed in this study for a quadrotor helicopter with state delay and actuator faults. Improved guaranteed cost control i...

Improved adaptive fuzzy sliding mode controller for robust fault tolerant of a Quadrotor

In this paper, a model for a Quadrotor helicopter has been considered when a fault has been occurred in its actuators. The sliding mode control technique has been utilized as one of a robust passive fault tolerant control methods to control the Quadrotor’s attitude. An adaptive fuzzy system, as a compensator has been used to compensate the estimation error of nonlinear functions and faulty parts. Although increasing the adaptation rate enhances the responding speed, it is accompanied by closed loop system instability. In order to avoid instability and to increase the robustness of the closed loop system, in this paper, a new parallel fuzzy system has been proposed along with a main fuzzy system. The adaptation rules of the main and parallel fuzzy systems were extracted from Lyapunov’s stability theory. During the numerical simulation, the efficiency of the proposed method has been shown against actuator faults.

A Flying Odor Compass to Autonomously Locate the Gas Source

The design of a flying odor compass is proposed for the localization of gas source. The compass is built on a quad-rotor helicopter and contains three gas sensors. A data processing method is proposed to estimate the direction which the odor comes from. The method adopts continuous wavelet transform and modulus maxima approaches to uncover the time difference information hidden in the gas sensor signals. Experiments have demonstrated the effectiveness of this design.

ブレーキ機構を備えた２輪型４ロータヘリコプタの自動制御

ブレーキ機構を備えた２輪型４ロータヘリコプタの自動制御

マイクロホンアレイを搭載したクアッドロータヘリコプタによる音源探査のための繰り返しベイズフィルタを利用した最適経路計画

マイクロホンアレイを搭載したクアッドロータヘリコプタによる音源探査のための繰り返しベイズフィルタを利用した最適経路計画

Real-time altitude control for a quadrotor helicopter using a super-twisting controller based on high-order sliding mode observer

This article addresses the problem of altitude tracking for unmanned aircraft system when the altitude velocity is unknown, because in a practical implementation, the available sensors used to measure the vehicle’s altitude (barometer, global positioning system, laser, etc.) do not provide the altitude velocity. We propose a control strategy based on both the super-twisting sliding mode controller as well as a high-order sliding mode observer to control and to estimate the altitude velocity, respectively. A comprehensive stability analysis for the combined controller–observer based on the Lyapunov stability theory is presented, ensuring the asymptotic convergence of the tracking error under external bounded disturbances. To demonstrate the performance and the effectiveness of the proposed solution, an extensive set of real-time experimental tests performed at outdoor environments is presented.

Adaptive Neural Control Algorithm Design for Attitude Stabilization of Quadrotor UAV

This paper presents a new adaptive neural network control scheme to stabilize the attitude of the quadrotor helicopter. The dynamic model was developed via Newton−Euler formalism. The robust adaptive control is then realized using neural network (NN) algorithm based on a PID controller in the aim to adjust its gain parameters. The proposed algorithm is developed to adapt the structure of the conventional PID controller to a dynamic PID controller. Finally, the proposed controller is compared with that classical PID controller using MATLAB/Simulink. The simulation results show that the neural PID controller produces better performance than the conventional one, particularly in case of perturbation.

Vision-based control of a quadrotor utilizing artificial neural networks for tracking of moving targets

This paper investigates the application of an image based visual servoing (IBVS) mechanism for controlling the translational and rotational movements of a quadrotor helicopter; via this scheme, the helicopter can track a moving target by means of a camera installed underneath. The image features chosen for this purpose are the perspective image features. A direct adaptive neural controller was designed to control transitional motion. The controller makes use of neural network controller radial basis function (RBF) to deal with the image dynamic uncertainties. These uncertainties relate to the depth of visual information and the movement of the considered target. Moreover, a sliding mode controller designed by using the image features has been presented for controlling the rotational movement of the helicopter. Also, due to the lack of accurate image velocity and the Euler angles, appropriate observers have been designed and used. The designed scheme needs no geometric information from the object followed by the quadrotor; therefore, this method can be employed in unknown environments. The simulation results for ideal and non-ideal conditions indicate that, in spite of the problems such as the uncertainty of the image depth and the mobility of the target, both in the rotational and translational motions, the helicopter has been able to reach the desired altitude and to properly track the moving target.

Flatness of Multi-Input Control-Affine Systems Linearizable via One-Fold Prolongation

We study flatness of multi-input control-affine systems. We give a geometric characterization of systems that become static feedback linearizable after an invertible one-fold prolongation of a suitably chosen control. They form a particular class of flat systems. Namely, they are of differential weight $n + m+1$, where $n$ is the dimension of the state-space and $m$ is the number of controls. We propose conditions (verifiable by differentiation and algebraic operations) describing that class and provide a system of PDEs giving all minimal flat outputs. We illustrate our results by several examples, in particular, an example of the quadrotor helicopter.

High-performance software control platform designed for the autonomous navigation of quad-rotor helicopter

In recent years, unmanned aerial vehicles have gained increasing popularity. They are employed in many applications due to its features in terms of flexibility, low cost, and small size. Due to special structure of mechanical system for the quad-rotor helicopter (typical small-sized unmanned aerial vehicle), one of the main research fields for quad-rotor helicopter is to improve its stability flight control so as to well implement its autonomous navigation. However, for the quad-rotor helicopter whose power is supplied by battery, the embedded operating system directly affects its flight performance; thus, it is of very importance to implement this goal. This article aims to put forward a high-performance software platform consisted of embedded operating system and JAVA virtual machine in the quad-rotor helicopter. Then, this article also proposes an autonomous control algorithm written by real-time JAVA application, which uses image entropy to avoid obstacles and optical flow to discover the most appropriate area to fly in while avoiding obstacles; besides, image identification with image contour detection is used for the cases of junction turn and landing. The practical experimental results show that the implemented software control platform and proposed autonomous flight application are component for indoor autonomous flight of quad-rotor helicopter.

Active disturbance rejection and predictive control strategy for a quadrotor helicopter

In this study, an active disturbance rejection and predictive control strategy is presented to solve the trajectory tracking problem for an unmanned quadrotor helicopter with disturbances. The proposed control scheme is based on the quadrotor's dynamic model, where effects of wind gust are considered as additive disturbances on six degrees of freedom. The predictive controller solves the path following problem with extended state observers to estimate and compensate disturbances. The active disturbance rejection control scheme is used for the stabilisation of rotational movements. The suggested control structure is verified in simulation studies with the presence of external disturbances and parametric uncertainties. The proposed method improves the robustness for the modelling error and disturbances while performing a smooth tracking of the reference trajectory.

Design, development, and flight testing of a high endurance micro quadrotor helicopter

This paper describes the experimental design studies conducted to maximize the hover endurance of a micro air vehicle-scale quadrotor helicopter (gross weight < 50 g) by careful design and selection of the individual subsystems while understanding their interdependencies. The different subsystems of the quadrotor that were examined include the rotors, motors, electronic speed controllers, gear transmission systems, battery, and airframe structure. An optimized micro air vehicle-scale rotor with a diameter of 110 mm and a figure of merit of 0.67 served as the basis for the vehicle design. Brushed and brushless motor systems were paired with the optimized rotor and were examined for maximum system level efficiency and capability to produce the required thrust. Propulsion systems using brushed motors with speed controllers and the optimum gear ratio showed up to 35% improvement in efficiency over brushless outrunner motors with speed controllers. Lithium-ion polymer batteries were compared and evaluated on voltage drop-off characteristics and achievable endurance versus weight. Quadrotor airframe weight has been minimized to 7.4% of the gross weight, representing a 30–50% decrease compared existing similarly sized quadrotors. The highest endurance was obtained using brushed motors with a 5.33:1 gear ratio and a 650 mAh battery. Presently, the longest continuous hover endurance achieved with this design is 31 min.

Disturbance observer-based feedback linearization control of an unmanned quadrotor helicopter

Feedback linearization is widely used for the purpose of quadrotor control. Unfortunately, feedback linearization is highly sensitive to any quadrotor model uncertainties. This paper provides feedback linearization-based control with robustness by integrating it with a disturbance observer. The proposed approach maintains the simplicity of the control structure without ignoring the high nonlinearities existing in the model by considering these nonlinearities as disturbances to be attenuated by the disturbance observer. Thus, the requirement to include complex high-order Lie derivatives in the controller is eliminated even in the presence of the high nonlinearities. Simulation results show that the proposed controller successfully force the quadrotor to follow the desired position and heading trajectories in the presence of different types of disturbances including ignored nonlinear dynamics, wind disturbances and partial actuator failure.

Forwarding-based trajectory tracking control for nonlinear systems with bounded unknown disturbances

There are only a few methods for controlling high-order nonlinear systems, except for standard backstepping technique. Due to the fact that I&I theory proposed by Astolfi and Ortega is able to accomplish the system immersion by selecting a lower-order target system and a vital mapping, a bottom-up recursive procedure for designing tracking control laws for a class of n-dimensional strict-feedback nonlinear systems is focused in our work. The required mappings are transformed into virtual control inputs, and system order reduction is realized as design step is implemented repetitively. A first-order filter is employed at each step to compute analytic derivatives of mappings. The benefit of our proposed algorithm can not only improve the computation efficiency to simplify all controls’ forms, but also suppress the high-frequency noise. While the off-the-manifold coordinate is rendered insensitive to the time-varying and bounded but unknown disturbance, the robust stability can be ultimately guaranteed. A quadrotor helicopter is used to show designing procedures and controller performance via various simulations.

Flight Characteristics of Quad Rotor Helicopter with Thrust Vectoring Equipment

[abstFig src='/00280003/09.jpg' width=""300"" text='Thrust vectoring mechanisms for WRH' ] A quad rotor helicopter (QRH) is a radio controlled (RC) aircraft that tilts its attitude to generate a horizontal force component to move in a certain direction. Using autonomous control, the attitude control system tilts the airframe against disturbances, such as wind. Thus, the attitude of a flying QRH is always slanted. In this study, three types of deflecting thruster were compared to maintain the position and horizontal attitude of the QRH. The extra thrusters are tilted to generate a thrust against disturbances without causing the airframe to incline. It is suitable for precise measurements for which the airframe posture should remain horizontal.

Reduced-Order Observer Based Sliding Mode Control for a Quad-Rotor Helicopter

[abstFig src='/00280003/05.jpg' width=""230"" text='Quadcopter for repeated control verification' ] The reduced-order observer design we present estimates the velocity states of a quadrotor helicopter, or quadcopter, based on sampled measurements of position and attitude states. This observer is based on the forward-differentiation Euler model. The observer is robust enough against observation noise that the gain of a closed-loop controller is high enough to improve control performance. A sliding-mode controller stabilizes and implements quadcopter tracking control effectively, as is verified experimentally when compared to a conventional backward-difference method.