Quadrotor Helicopter Research Articles

Event-driven PID control of autonomous quadrotor helicopters

This paper proposes an event-driven PID control mechanism for autonomous quadrotor helicopters that will reduce the usage of communication channels. Compared to traditional PID controller, the event-driven PID controller can maintain the satisfactory stabilization effect with the ability of reducing the number of transmissions significantly. The simplified dynamics model of quadrotor helicopter is also established. Finally, the improvements realized by the developed method are verified in the computer simulations.

A novel hybrid model predictive control design with application to a quadrotor helicopter

SummaryIn this paper, a novel control design strategy based on a hybrid model predictive control in combination with fuzzy logic control is presented for a quadrotor helicopter system. In the proposed scheme, a 2‐part control structure is used. In the first part, a linear model predictive controller with receding horizon design strategy is combined with a nonlinear model predictive controller, which is applied as the main controller. In the second part, a 2‐level fuzzy logic controller is utilized to assist the first controller when the error exceeds a predefined value. The proposed nonlinear predictive control method utilizes a novel approach in which a prediction of the future outputs is used in the modeling stage. Using this simple technique, the problem can be solved using linear methods and, thereby, due to considerable reduction in the computational cost, it will be applicable for the systems with fast dynamics. Moreover, the fuzzy logic controller is used as a supervisor to adjust a proportional‐integral‐derivative controller to enhance the system performance by decreasing the tracking error. The proposed scheme is applied to a model of quadrotor system such that the difference between the predicted output of the system and the reference value is minimized while there are some constraints on inputs and outputs of the nonlinear quadrotor system. Simulation results demonstrate the efficiency of the proposed control scheme for the quadrotor system model.

Development of a robust attitude control for nonidentical rotor quadrotors using sliding mode control

This work proposes a novel development of sliding mode control (SMC) for quadrotor helicopters utilizing offset cancellation technique. Most of the works on sliding mode control for quadrotors assumed that all rotors were identical, but in fact, the rotors even from the same factory are not exactly the same in aerodynamics properties. In addition, rotor deformation due to shock or heavy usage during operation may cause changes in parameters such as lift and drag coefficients, and so on, which, lead to offset error in the responses of attitude control. By applying the proposed offset cancellation technique to the sliding mode control, the attitude error is forced to have a zero average. The proposed controller is used to control attitude and position of a quadrotor helicopter which is composed of four direct current (DC) brushless motors to generate lift forces independently. Performance comparison with the other control algorithms such as the proportional–integral–derivative controller and the conventional sliding mode control is simulated and experimented on two real quadrotor platforms and results are discussed.

Simplified fuzzy ‐Padé controller for attitude control of quadrotor helicopters

In this study, a simplified fuzzy-Pade controller (FPC) for attitude control of quadrotor helicopters is proposed, which is non-linear, fractional, and model independent. To determine some of the unknown coefficients of the Pade approximant, a proportional-derivative-type fuzzy logic controller (FLC) is first designed. The responses of the simplified FPC due to step set-point manoeuvres are compared with those of the FLC in terms of several performance indices such as rise time, settling time, percentage overshoot, integral absolute error, integral of time multiplied by AE, central processing unit time, and energy consumption. Simulation results demonstrate that in each case the proposed FPC presents an improved performance over the FLC. The asymptotic stability of the simplified FPC is proved with Lyapunov stability theory and La Salle's invariant set theorem. Unlike the FLC, the proposed FPC is simple enough to be implemented on the on-board electronics of the quadrotor. Flight experiments in hovering conditions are given to demonstrate the effectiveness of the simplified FPC.

Comparison of Parameter-Varying Decoupling Based Control Schemes for a Quadrotor

Abstract This paper presents and compares approaches to the design of flight controllers for quadrotor helicopters based on Linear Parameter-Varying (LPV) decoupling techniques. It is shown that parameter-varying decoupling makes it possible to use SISO LTI control design to address all degrees of motion freedom subject to high-speed maneuvers that require large pitch and roll angles. Specifically a decoupling method based on local linearizations (gain-scheduling decoupling) is compared to a global scheduling-dependent decoupling method inspired by computed-torque control, where the scheduling is based on the tilt angels of the drone. Based on an extensive simulation study, it is demonstrated that such a relatively simple control architecture can achieve significantly better performance than LTI control. Conceptually, the presented techniques can be used for the design of control schemes for aircraft and missiles.

Tracking Control of Two-wheeled Quadrotor Helicopter Moving on Ground and Ceiling

Tracking Control of Two-wheeled Quadrotor Helicopter Moving on Ground and Ceiling

Actuator and Sensor Fault Detection and Diagnosis for Unmanned Quadrotor Helicopters

In this paper, the problem of actuator and sensor fault detection and diagnosis (FDD) for unmanned quadrotor helicopters (UQHs) is addressed by utilizing the interacting multiple model (IMM) approach. The mathematical model of UQHs, including actuator and sensor faults, is firstly introduced. Actuator faults are modelled as the loss of control effectiveness in motors and sensor faults are assumed to be bias fault. In order to reduce the intensive computational load due to the large fault model set, a state augmentation (SA) strategy is applied. This strategy can not only reduce the number of elemental filter, but also identify the magnitude of faults. Through combining the IMM algorithm and the SA strategy, the proposed FDD scheme can effectively detect and diagnose multiple actuator and sensor faults. Finally, the effectiveness of the FDD scheme is validated by two simulation scenarios, and the obtained results prove that the proposed scheme is an effective tool to deal with actuator and sensor faults.

Neural network fuzzy control for enhancing the stability performance of quad-rotor helicopter

Recently, the quad-rotor helicopter has gained increasing attention owing to its very good flexibility, its ability to execute various flight missions even in harsh environments. The quad-rotor helicopter can implement different fight attitudes, which is attributed to the effective control of the motor speed about four propellers. In order to make the quad-rotor helicopter can better finish flight mission, the performance of flight stability then becomes particularly important. A neural network fuzzy control algorithm is proposed in this paper so as to guarantee the stability performance of the quad-rotor helicopter. The proposed algorithm is based on the neural network, which keeps the self-organization and self-learning ability, besides this, it utilizes the strong impression ability of constitutive knowledge as to the fuzzy logic. The proposed control scheme aims to implement good abilities such as describing qualitative knowledge, strong learning mechanism and direct processing about quantitative data of the quad-rotor helicopter. In the practical flight process of the quad-rotor helicopter, while the deviation of position and attitude information become larger, fuzzy control is adopted so as to shorten the overshoot and adjustment time. On the other hand, if the deviation of position and attitude become relatively smaller, neural network PID control will be used so as to reduce the error. Experimental results show that the proposed neural network fuzzy control algorithm exhibits good performance in the flight process of the quad-rotor helicopter.

Trajectory Tracking Control of Autonomous Quadrotor Helicopter Using Robust Neural Adaptive Backstepping Approach

AbstractThis paper presents the design and analysis of a robust neural adaptive backstepping control (RNABC) for an autonomous quadrotor helicopter perturbed by time-varying external disturbances. ...

Adaptive fault tolerant control for trajectory tracking of a quadrotor helicopter

In this paper, an adaptive fault tolerant controller based on [Formula: see text] control is developed and applied to the trajectory tracking for a quadrotor helicopter. Both multiplicative and additive actuator faults are considered. The proposed design is based on nonlinear feed-forward compensations and a typical nonlinear quadrotor model with uncertain inertial parameters and external disturbances. The [Formula: see text] adaptive control design is slightly modified to adapt with the position and the attitude error dynamics. The proposed adaptive controller yields uniformly verifiable bounds on the transient and the steady-state tracking error for any designated bounded reference trajectory. In the presence of fast adaptation, the adaptive controller compensates for actuator fault and disturbances in a particular frequency range. Finally, simulation results are included to validate the effectiveness of the proposed design.

Adaptive Sliding Mode Fault-Tolerant Control for an Unmanned Aerial Vehicle

Sliding mode control (SMC) is known as a robust control method to maintain system performance and keep it insensitive to system uncertainties. To achieve this objective, the knowledge of the uncertainty bound is usually needed, but sometimes it could be a hard task. Hence, the adaptive technology is introduced to be synthesized with SMC. In this paper, a novel adaptive SMC (ASMC) scheme is proposed to accommodate system uncertainties caused by actuator faults. An integral sliding mode controller is used as the baseline controller. When actuator faults occur, there is no need to know the exact bound of the uncertainties in control effectiveness matrix. The post-fault control effectiveness matrix can be estimated by the proposed adaptive control scheme, and the control inputs will be changed accordingly. In such a way, the robustness of the controller to actuator faults is improved. With the help of adaptive change of both continuous and discontinuous control parts, a minimum value of the discontinuous control gain can be guaranteed. In this case, the resulting control effort is reduced accordingly to avoid control chattering effect. Owing to the minimized control effort to accommodate uncertainties compared to the conventional SMC, the proposed ASMC can still maintain the system performance when severer faults occur. The effectiveness of the developed algorithm is demonstrated by the simulation results based on an unmanned quadrotor helicopter under various faulty conditions.

Composite Hierarchical Anti-Disturbance Control of a Quadrotor UAV in the Presence of Matched and Mismatched Disturbances

Quadrotor helicopter is an unstable system subject to matched and mismatched disturbances. To stabilize the quadrotor dynamics in the presence of these disturbances, the application of a composite hierarchical anti-disturbance controller, combining a sliding mode controller and a disturbance observer, is presented in this paper. The disturbance observer is used to attenuate the effect of constant and slow time-varying disturbances. Whereas, the sliding mode controller is used to attenuate the effect of fast time-varying disturbances. In addition, sliding mode control attenuates the effect of the disturbance observer estimation errors of the constant and slow time-varying disturbances. In this approach, the upper bounds of the disturbance observer estimation errors are required instead of the disturbances’ upper bounds. The disturbance observer estimation errors are found to be bounded when the disturbance observer dynamics are asymptotically stable and the disturbance derivatives and initial disturbances are bounded. Moreover, due to the highly nonlinear nature of the quadrotor dynamics, the upper bounds of a part of the quadrotor states and disturbance estimates are required. The nonlinear terms in the rotational dynamics are considered as disturbances, part of which is mismatched. This assumption simplifies the control system design by dividing the quadrotor’s model into a position subsystem and a heading subsystem, and designing a controller for each separately. The stability analysis of the closed loop system is carried out using Lyapunov stability arguments. The effectiveness of the developed control scheme is demonstrated in simulations by applying different sources of disturbances such as wind gusts and partial actuator failure.

Study on the sliding mode fault tolerant predictive control based on multi agent particle swarm optimization

For a class of uncertain discrete-time systems with time varying delay, the problem of robust fault-tolerant control for such systems is studied by combining the design of sliding mode control (SMC) and model predictive control (MPC). A sliding mode fault tolerant predictive control based on multi agent particle swarm optimization (PSO) is presented, and the design, analysis and proof of the scheme are given in detail. Firstly, the sliding mode prediction model of the system is designed by assigning poles of the output error of the system. The model has time varying characteristics, and it can improve the motion quality of the system while ensuring the sliding mode is stable. Secondly, a new discrete reference trajectory considering time-delay systems subjected simultaneously to parameter perturbations and disturbances is proposed, which not only can ensure that the state of the system has good robustness and fast convergence in the process of approaching sliding mode surface, but also can inhibit chattering phenomenon. Thirdly, the multi agent PSO improves the receding-horizon optimization, which can quickly and accurately solve the control laws satisfying the input constraints, and can effectively avoid falling into local extrema problem of the traditional PSO. Finally, the theoretical proof of robust stability of the proposed control scheme is given. Experimental results of quad-rotor helicopter semi physical simulation platform show that the state of uncertain discrete-time systems with time varying delay is stable under the action of the proposed control scheme in this paper. The advantages of fast response, less overshoot and small control chattering prove the feasibility and effectiveness of the proposed control scheme.

Modeling, System Identification and PID-A Controller for Tethered Unmanned Quad-Rotor Helicopter

In this paper, a strategy for the preliminary design of Quad-Rotor problem with emphasis on utilizing system identification methods for system modeling. The algorithm of forgetting least square is applied for the realtime prediction of the system parameters. The presented strategy is applied to the mass-varying tethered Quad-Rotor. The presented system identification method provides the model parameters while the adaptive (Proportional, Integral, Derivative, and Accelerator) PID-A controller controls the system response in real-time flight. In this paper, a mathematical model for the Quad-Rotor is derived. The sensitivity analys is of the system is provided in detail. Then, a system identification algorithm is applied to study the change in parameters during flight. PID-A controller is designed to stabilize the system with mass-varying consideration. Finally, Simulation results of the full system are presented.

Retrofit fault‐tolerant tracking control design of an unmanned quadrotor helicopter considering actuator dynamics

SummaryThis paper presents a retrofit fault‐tolerant tracking control (FTTC) design method with application to an unmanned quadrotor helicopter (UQH). The proposed retrofit fault‐tolerant tracking controller is developed to accommodate loss‐of‐effectiveness faults in the actuators of UQH. First, a state feedback tracking controller acting as the normal controller is designed to guarantee the stability and satisfactory performance of UQH in the absence of actuator faults, while actuator dynamics of UQH are also considered in the controller design. Then, a retrofit control mechanism with integration of an adaptive fault estimator and an adaptive fault compensator is devised against the adverse effects of actuator faults. Next, the proposed retrofit FTTC strategy, which is synthesized by the normal controller and an additional reconfigurable fault compensating mechanism, takes over the control of the faulty UQH to asymptotically stabilize the closed‐loop system with an acceptable performance degradation in the presence of actuator faults. Finally, both numerical simulations and practical experiments are conducted in order to demonstrate the effectiveness of the proposed FTTC methodology on the asymptotic convergence of tracking error for several combinations of loss‐of‐effectiveness faults in actuators.

A novel hybrid back-stepping and fuzzy logic control strategy for a quadcopter

ABSTRACTThis article aims to present a novel control strategy for quadrotor helicopter. It is composed of three main parts constituting the system modelling, the integral back-stepping control, and fuzzy logic compensator. In the first part, a non-linear model is presented taking in consideration some non-linearities and variables that are usually neglected. In the second part, a controller based on the integral back-stepping algorithm has been developed for the system in order to make the system follows a desired path. However, due to complexity of paths and to the presence of unknown disturbances, a fuzzy logic compensator is added in parallel to the integral back-stepping controller to improve trajectory tracking in some critical conditions (high wind speed, mass variation, etc.). Simulation results have been presented to show the effectiveness of the proposed approach.

Local and Distributed Rendezvous of Underactuated Rigid Bodies

This paper solves the rendezvous problem for a network of underactuated rigid bodies such as quadrotor helicopters. A control strategy is presented that makes the centres of mass of the vehicles converge to an arbitrarily small neighborhood of one another. The convergence is global, and each vehicle can compute its own control input using only an on-board camera and a three-axis rate gyroscope. No global positioning system is required, nor any information about the vehicles' attitudes.

Learning Quadcopter Maneuvers with Concurrent Methods of Policy Optimization

This study presents an aerial robotic application of deep reinforcement learning that imparts an asynchronous learning framework and trust region policy optimization to a simulated quad-rotor helicopter (quadcopter) environment. In particular, we optimized a control policy asynchronously through interaction with concurrent instances of the environment. The control system was benchmarked and extended with examples to tackle continuous state-action tasks for the quadcoptor: hovering control and balancing an inverted pole. Performing these maneuvers required continuous actions for sensitive control of small acceleration changes of the quadcoptor, thereby maximizing the scalar reward of the defined tasks. The simulation results demonstrated an enhancement of the learning speed and reliability for the tasks.

Stable Path-Following Control for a Quadrotor Helicopter Considering Energy Consumption

A substantial interest in aerial robots has grown in recent years. However, the energetic cost of flying is one of the key challenges nowadays. Rotorcrafts are heavier-than-air flying machines that use lift generated by one or several rotors (vertically oriented propellers), and because of this, they spend a large proportion of their available energy to maintain their own weight in the air. In this brief, this concept is used to evaluate the relationship between navigation speed and energy consumption in a miniature quadrotor helicopter, which travels over a desired path. A novel path-following controller is proposed in which the speed of the rotorcraft is a dynamic profile that varies with the geometric requirements of the desired path. The stability of the control law is proved using the Lyapunov theory. The experimental results using a real quadrotor show the good performance of the proposed controller, and the percentages of involved energy are quantified using a model of a lithium polymer battery that was previously identified.

Multivariable finite‐time output feedback trajectory tracking control of quadrotor helicopters

SummaryA continuous multivariable output feedback control scheme is developed for trajectory tracking and attitude stabilization of quadrotor helicopters. The whole closed‐loop system is composed by position loop and attitude loop. The homogeneous technique is used to design finite‐time stabilizing controller and observer in each loop. The virtual control is introduced in position loop to ensure that the real control is smooth enough such that it can be tracked by attitude loop. The finite‐time stability of the closed‐loop system is guaranteed through homogeneity and Lyapunov analysis. Finally, the efficiency of the proposed algorithm is illustrated by numerical simulations.