All Outputs (87)

Adaptive sliding mode attitude control of 2-degrees-of-freedom helicopter system with actuator saturation and disturbances (2023)
Journal Article
Li, R., Lei, C., Shi, B., Zhu, Q., & Yue, X. (in press). Adaptive sliding mode attitude control of 2-degrees-of-freedom helicopter system with actuator saturation and disturbances. Journal of Vibration and Control, https://doi.org/10.1177/10775463231212530

The modelling uncertainties, external disturbance and actuator saturation issues will degrade the performance and even the safety of flight. To improve control performance, this study proposes an adaptive U-model based double sliding control (UDSMC)... Read More about Adaptive sliding mode attitude control of 2-degrees-of-freedom helicopter system with actuator saturation and disturbances.

Model-free robust decentralised control of multi-input-multi-output nonlinear interconnected dynamic systems (2023)
Journal Article
Zhu, Q., Li, R., Zhang, J., & Shi, B. (in press). Model-free robust decentralised control of multi-input-multi-output nonlinear interconnected dynamic systems. Journal of Vibration and Control, https://doi.org/10.1177/10775463231206601

This study presents a generalised framework for model-free robust decentralised control (MFRDC) of interconnected MIMO dynamic systems, with the goal of significantly reducing complexity in model-based design. A model-free robust sliding mode control... Read More about Model-free robust decentralised control of multi-input-multi-output nonlinear interconnected dynamic systems.

Neural network-enhanced fault diagnosis of robot joints (2023)
Journal Article
Zhang, Y., & Zhu, Q. (2023). Neural network-enhanced fault diagnosis of robot joints. Algorithms, 16(10), Article 489. https://doi.org/10.3390/a16100489

Industrial robots play an indispensable role in flexible production lines, and the faults caused by degradation of equipment, motors, mechanical system joints, and even task diversity affect the efficiency of production lines and product quality. Aim... Read More about Neural network-enhanced fault diagnosis of robot joints.

Two iterative reweighted algorithms for systems contaminated by outliers (2023)
Journal Article
Chen, J., Hu, M., Liu, Y., & Zhu, Q. (2023). Two iterative reweighted algorithms for systems contaminated by outliers. IEEE Transactions on Instrumentation and Measurement, 72, https://doi.org/10.1109/tim.2023.3308255

This study proposes two iterative reweighted (IRE) algorithms for systems whose data are contaminated by outliers. For the negative effect caused by the outliers, traditional least squares (LSs) and gradient descent (GD) algorithms cannot obtain unbi... Read More about Two iterative reweighted algorithms for systems contaminated by outliers.

Model-free robust decoupling control of nonlinear nonaffine dynamic systems (2023)
Journal Article
Zhu, Q., Li, R., & Zhang, J. (2023). Model-free robust decoupling control of nonlinear nonaffine dynamic systems. International Journal of Systems Science, 54(13), 2590-2607. https://doi.org/10.1080/00207721.2023.2245543

This study presents a model-free robust input-output decoupling control with Nonlinear-Dynamic-Coupling Inversion/Inverter (NDCI) in a U-control framework. Regarding the decoupling, an input/output (I/O) coupling matrix function is proposed to derive... Read More about Model-free robust decoupling control of nonlinear nonaffine dynamic systems.

Model-free sliding mode enhanced proportional, integral, and derivative (SMPID) control (2023)
Journal Article
Zhu, Q. (2023). Model-free sliding mode enhanced proportional, integral, and derivative (SMPID) control. Axioms, 12(8), Article 721. https://doi.org/10.3390/axioms12080721

This study proposes a type of Sliding Mode-based Proportional, Integral, and Derivative (SMPID) controllers to establish a model-free (treat dynamic plants as a whole uncertainty) sliding model control (MFSMC) platform for Bounded-Input and Bounded-O... Read More about Model-free sliding mode enhanced proportional, integral, and derivative (SMPID) control.

Non-predictive model-free control of nonlinear systems with unknown input time delay (2023)
Journal Article
Zhu, Q., Zhang, J., & Zhang, W. (2023). Non-predictive model-free control of nonlinear systems with unknown input time delay. Entropy, 25(7), Article 1076. https://doi.org/10.3390/e25071076

This study presents a general framework for the control of unknown dynamic systems with unknown input delay. A concise output feedback control system is structured with tuning stabilization/dynamic response by an output feedback low gain, removing st... Read More about Non-predictive model-free control of nonlinear systems with unknown input time delay.

Trajectory tracking of a quadrotor using extend state observer based U-model enhanced double sliding mode control (2023)
Journal Article
Li, R., Zhu, Q., Nemati, H., Yue, X., & Narayan, P. (2023). Trajectory tracking of a quadrotor using extend state observer based U-model enhanced double sliding mode control. Journal of The Franklin Institute, 360(4), 3520-3544. https://doi.org/10.1016/j.jfranklin.2022.11.036

This paper develops a novel U-model enhanced double sliding mode controller (UDSMC) for a quadrotor based on multiple-input and multiple-output extended-state-observer (MIMO-ESO). UDSMC is designed using Lyapunov synthesis and Hurwitz stability to no... Read More about Trajectory tracking of a quadrotor using extend state observer based U-model enhanced double sliding mode control.

A comprehensive review of scab disease detection on Rosaceae family fruits via UAV imagery (2023)
Journal Article
Ali, Z. A., Yang, C., Israr, A., & Zhu, Q. (2023). A comprehensive review of scab disease detection on Rosaceae family fruits via UAV imagery. Drones, 7(2), 97. https://doi.org/10.3390/drones7020097

Disease detection in plants is essential for food security and economic stability. Unmanned aerial vehicle (UAV) imagery and artificial intelligence (AI) are valuable tools for it. The purpose of this review is to gather several methods used by our p... Read More about A comprehensive review of scab disease detection on Rosaceae family fruits via UAV imagery.

Second-order optimization methods for time-delay Autoregressive eXogenous models: Nature gradient descent method and its two modified methods (2022)
Journal Article
Chen, J., Pu, Y., Guo, L., Cao, J., & Zhu, Q. (2023). Second-order optimization methods for time-delay Autoregressive eXogenous models: Nature gradient descent method and its two modified methods. International Journal of Adaptive Control and Signal Processing, 37(1), 211-223. https://doi.org/10.1002/acs.3519

This article proposes several second-order optimization methods for time-delay ARX model. Since the time-delay in the information vector makes the traditional identification algorithms be inefficient, a redundant rule based method is utilized to tran... Read More about Second-order optimization methods for time-delay Autoregressive eXogenous models: Nature gradient descent method and its two modified methods.

Greedy search method for separable nonlinear models using stage Aitken gradient descent and least squares algorithms (2022)
Journal Article
Chen, J., Mao, Y., Gan, M., Wang, D., & Zhu, Q. (2023). Greedy search method for separable nonlinear models using stage Aitken gradient descent and least squares algorithms. IEEE Transactions on Automatic Control, 68(8), 5044-5051. https://doi.org/10.1109/TAC.2022.3214474

Aitken gradient descent (AGD) algorithm takes some advantages over the standard gradient descent (SGD) and Newton methods: (1) can achieve at least quadratic convergence in general; (2) does not require the Hessian matrix inversion; (3) has less comp... Read More about Greedy search method for separable nonlinear models using stage Aitken gradient descent and least squares algorithms.

U-Model-Based adaptive sliding mode control using a deep deterministic policy gradient (2022)
Journal Article
Lei, C., & Zhu, Q. (2022). U-Model-Based adaptive sliding mode control using a deep deterministic policy gradient. Mathematical Problems in Engineering, 2022, 1-14. https://doi.org/10.1155/2022/8980664

This paper presents a U-model-based adaptive sliding mode control (SMC) using a deep deterministic policy gradient (DDPG) for uncertain nonlinear systems. The configuration of the proposed methodology consisted of a U-model framework and an SMC with... Read More about U-Model-Based adaptive sliding mode control using a deep deterministic policy gradient.

Modified multi-direction iterative algorithm for separable nonlinear models with missing data (2022)
Journal Article
Chen, J., Hu, M., Mao, Y., & Zhu, Q. (2022). Modified multi-direction iterative algorithm for separable nonlinear models with missing data. IEEE Signal Processing Letters, 29, 1968-1972. https://doi.org/10.1109/LSP.2022.3204408

Multi-direction iterative (MUL-DI) algorithm is an efficient algorithm for large-scale models, and it establishes a theoretical linkage between least squares (LS) and gradient descent (GD) algorithms. However, it involves Givens transformation and de... Read More about Modified multi-direction iterative algorithm for separable nonlinear models with missing data.

Hierarchical multi-innovation stochastic gradient identification algorithm for estimating a bilinear state-space model with moving average noise (2022)
Journal Article
Gu, Y., Dai, W., Zhu, Q., & Nouri, H. (2023). Hierarchical multi-innovation stochastic gradient identification algorithm for estimating a bilinear state-space model with moving average noise. Journal of Computational and Applied Mathematics, 420, 114794. https://doi.org/10.1016/j.cam.2022.114794

This paper considers the combined parameter and state estimation problem of a bilinear state space system with moving average noise. There are product terms of state variables and control variables in bilinear systems, which brings difficulties to pa... Read More about Hierarchical multi-innovation stochastic gradient identification algorithm for estimating a bilinear state-space model with moving average noise.

Robust adaptive dynamic surface control scheme for a class of single‐input and single‐output uncertain nonlinear systems in strict‐feedback form (2022)
Journal Article
Soukkou, Y., Tadjine, M., Nibouche, M., & Zhu, Q. (2022). Robust adaptive dynamic surface control scheme for a class of single‐input and single‐output uncertain nonlinear systems in strict‐feedback form. International Journal of Adaptive Control and Signal Processing, 36(11), 2938-2952. https://doi.org/10.1002/acs.3486

This article presents a robust adaptive dynamic surface control using σ-modification adaptation laws for a class of single-input and single-output (SISO) uncertain nonlinear systems in strict-feedback form with parametric uncertainties and external d... Read More about Robust adaptive dynamic surface control scheme for a class of single‐input and single‐output uncertain nonlinear systems in strict‐feedback form.

An improved U-control design for nonlinear systems represented by input/output differential models with a disturbance observer (2022)
Journal Article
Li, R., Zhu, Q., Zhang, W., Yue, X., & Narayan, P. (2023). An improved U-control design for nonlinear systems represented by input/output differential models with a disturbance observer. International Journal of Control, 96(11), 2737-2748. https://doi.org/10.1080/00207179.2022.2111370

This paper presents a new method to calculate the inversion of the controlled linear/nonlinear dynamic plants which are described by input–output differential equation models. This new U-model-based inverter (U-inverter), cancels both system dynamics... Read More about An improved U-control design for nonlinear systems represented by input/output differential models with a disturbance observer.

A comprehensive expectation identification framework for multirate time-delayed systems (2022)
Journal Article
Chen, J., Gao, J., Liu, Y., Wang, C., & Zhu, Q. (2023). A comprehensive expectation identification framework for multirate time-delayed systems. IEEE Transactions on Industrial Informatics, 19(5), 7011-7021. https://doi.org/10.1109/TII.2022.3194656

The expectation maximization (EM) algorithm has been extensively used to solve system identification problems with hidden variables. It needs to calculate a derivative equation and perform a matrix inversion in the EM-M step. The equations related to... Read More about A comprehensive expectation identification framework for multirate time-delayed systems.

Least square algorithm based on bias compensated principle for parameter estimation of canonical state space model (2022)
Journal Article
Liu, L., Long, Z., Azar, A. T., Zhu, Q., Ibraheem, I. K., & Humaidi, A. J. (2022). Least square algorithm based on bias compensated principle for parameter estimation of canonical state space model. Measurement and Control, 55(5-6), https://doi.org/10.1177/00202940211064179

Due to the existence of system noise and unknown state variables, it is difficult to realize unbiased estimation with minimum variance for the parameter estimation of canonical state space model. This paper presents a new least squares estimator base... Read More about Least square algorithm based on bias compensated principle for parameter estimation of canonical state space model.

Adaptive fixed-time neural networks control for pure-feedback non-affine nonlinear systems with state constraints (2022)
Journal Article
Li, Y., Zhu, Q., Zhang, J., & Deng, Z. (2022). Adaptive fixed-time neural networks control for pure-feedback non-affine nonlinear systems with state constraints. Entropy, 24(5), 737. https://doi.org/10.3390/e24050737

A new fixed-time adaptive neural network control strategy is designed for pure-feedback non-affine nonlinear systems with state constraints according to the feedback signal of the error system. Based on the adaptive backstepping technology, the Lyapu... Read More about Adaptive fixed-time neural networks control for pure-feedback non-affine nonlinear systems with state constraints.

Robust variable-step perturb-and-observe sliding mode controller for grid-connected wind-energy-conversion systems (2022)
Journal Article
Toumi, I., Meghni, B., Hachana, O., Azar, A. T., Boulmaiz, A., Humaidi, A. J., …Bahgaat, N. K. (in press). Robust variable-step perturb-and-observe sliding mode controller for grid-connected wind-energy-conversion systems. Entropy, 24(5), 731. https://doi.org/10.3390/e24050731

In order to extract efficient power generation, a wind turbine (WT) system requires an accurate maximum power point tracking (MPPT) technique. Therefore, a novel robust variable-step perturb-and-observe (RVS-P&O) algorithm was developed for the machi... Read More about Robust variable-step perturb-and-observe sliding mode controller for grid-connected wind-energy-conversion systems.