All Outputs (132)

Variable projection algorithm for GPS positioning in multipath environments based on Aitken acceleration method (2024)
Journal Article

The multipath effect often reduce global positioning system (GPS) positioning accuracy. Traditional GPS positioning methods usually ignore the multipath effect errors, resulting in poor positioning estimation accuracy. This article proposes a variabl... Read More about Variable projection algorithm for GPS positioning in multipath environments based on Aitken acceleration method.

Feedback stabilization of a class of nonlinear systems using nonlinear normal form (2023)
Presentation / Conference Contribution

This paper investigates the design of a feedback controller via nonlinear normal form for a class of nonlinear systems. A general second-order nonlinear system affine in control is firstly presented. In general, it is more difficult to construct a no... Read More about Feedback stabilization of a class of nonlinear systems using nonlinear normal form.

Adaptive sliding mode attitude control of 2-degrees-of-freedom helicopter system with actuator saturation and disturbances (2023)
Journal Article

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.