Semi-Global Output Feedback Tracking Control for Fully Actuated Ships

Jialu Du,Shuanghe Yu,Xingru Wang 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

In this paper a new output feedback trajectory tracking controller for fully actuated ships is designed whenonly the position and the heading measurements are available. The considered 3 DOF ship model includes the Coriolisand Centripetal induced forces and moments and a nonlinear damping term. The gains of the constructed observer arenonlinear and time-variant, which can be used to globally dominate the difficult term resulting from the Coriolis andCentripetal term in the observer error dynamics. The acquired output feedback tracking control system is proveduniformly semi-globally exponential stable by applying nonlinear cascaded system theory. Furthermore, simulationstudies are carried out by utilizing Matlab’s Simulink Toolbox. Simulation results on a model ship Cybership II arepresented to validate the proposed output feedback tracking controller with a separate stability result for observer.

Robust Adaptive Finite-time Fault-tolerant Control for Dynamic Positioning of Vessels

Yongyi Lin,Jialu Du,Jian Li 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.9

In this paper, a novel robust adaptive finite-time fault-tolerant control (FTC) scheme is presented for the dynamic positioning (DP) of vessels under thruster faults with unknown model parameters and environmental disturbances. The thruster effectiveness factor to express the loss-of-effectiveness fault state is transformed into a new unknown parameter, which is obtained by the adaptive law. Furthermore, based on the finite-time control technique, neural networks (NNs) technique and the sliding mode differentiator, a novel robust adaptive finite-time FTC strategy is developed for DP of vessels by resorting the backstepping design technique. It is theoretically proved that the proposed FTC scheme can force the vessel arrive at the desired position and heading in a finite time, while guaranteeing the boundedness of all signals in the closed-loop of DP control system. Simulation study results are provided to demonstrate the effectiveness of the proposed FTC scheme.

Command filtered adaptive NN trajectory tracking control of underactuated autonomous underwater vehicles

Jian Li,Jialu Du 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

In this paper, an adaptive neural network (NN) trajectory tracking control scheme is developed for underactuated autonomous underwater vehicles (AUVs) subject to unknown dynamic parameters and unknown disturbances. A novel additional control based on Nussbaum function is proposed to handle the underactuation problem of AUVs. The radial basis function NNs with minimal learning parameter (MLP) are employed to online approximate the compounded uncertain item due to unknown dynamic parameters and unknown disturbances. On the basics of the above, an adaptive NN trajectory tracking control law is proposed using command filtered vector-backstepping design tool. As a result, the computational burden of the developed trajectory tracking control scheme is significantly reduced. Theoretical analysis indicates that the proposed control law can force the AUV track the desired trajectory and guarantee that all signals in the trajectory tracking closed-loop control system are bounded. Simulation results on an AUV verify the effectiveness of our developed control scheme.

SIFT-Based 3D Feature Matching and Reconstruction with Binocular Stereo Vision

Shuanghe Yu,Jialu Du,Siyuan Wang,He Xu 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

In this paper, we address the problem of 3D (three-dimensional) feature matching and reconstruction method with SIFT(scale invariant feature transform)-based algorithm under binocular stereo vision. The technique is fulfilled by camera calibration, image processing, feature detection and 3D calculation. Zhang plane-based calibration and Harris corner point detection method are utilized for Camera calibration. SIFT algorithm is focused as feature extraction and matching algorithm to obtain the image coordinates of matching points. The obtained 3D coordinates are validated by the measurement results with a laser sensor. Finally the depth map of 3D environment is produced with the measured results. VC++.NET and OpenCV are used to compile the algorithm for the experiment in this research.

Adaptive Robust Course-tracking Control of Time-varying Uncertain Ships with Disturbances

Rui Wu,Jialu Du 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.7

In this paper, we address the problem of course-tracking for ships with unknown time-varying parameters, completely unknown time-varying control coefficient, and unknown time-varying bounded environmentaldisturbances. Incorporating a Nussbaum function and an adaptive law into the backstepping design method, wepropose a course-tracking control law. The strict stability analysis shows that the designed course-tracking controllaw makes the course-tracking error settle into an arbitrarily small compact and guarantees the global uniform ultimate boundedness of all signals of the resulting closed-loop system by appropriately choosing design parameters. Simulation results and simulation comparisons on two ships demonstrate the effectiveness and the superiority ofthe proposed course-tracking control law.

Adaptive fast nonsingular terminal sliding mode control for underactuated surface vessel trajectory tracking

Junfeng Qin,Jialu Du 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

In this paper, we investigate the trajectory tracking control problem for underactuated surface vessels (USVs) in the presence of time-varying disturbances with unknown upper bounds. First, in order to handle the underactuation of the USVs, we introduce a coordinate transformation to redefine the output variables of the USVs. Then, the adaptive trajectory tracking control law is proposed based on the adaptive fast nonsingular terminal sliding mode (FNTSM) control technique, where the adaptive law online provides the estimation of the parameters. It is proved that the designed control law can force the USV to track the desired trajectory and tracking errors of closed-loop system converge to zero in finite time. Simulation results on an underactuated model ship verify the effectiveness of the proposed control law.

Robust Fuzzy Controller Design for Dynamic Positioning System of Ships

Werneld Egno Ngongi,Jialu Du,Rui Wang 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.5

This paper presents a robust fuzzy controller design approach for dynamic positioning (DP) system of ships using optimal H∞ control techniques. The H∞ control technique is used to exterminate the effects of environmental disturbances. Firstly, a Takagi-Sugeno (TS) fuzzy model is applied to approximate the nonlinear DP system. Next, linear matrix inequality (LMI) and general eigenvalue problem (GEVP) methods are employed to find a positive definite matrix and controller gains. The stability of the controller is proven by using Lyapunov stability theorems. A positive definite matrix is determined by solving LMI equations using robust control toolbox available in MATLAB. The obtained positive definite matrix proves that the designed fuzzy controller is stable. Finally, a uniformly ultimately bound (UUB) and control performance for the dynamic position system is guaranteed. Simulation is carried out, and results are presented to validate the effectiveness and performance of the proposed control system.

Fuzzy Control with Pole Assignment and Variance Constraints for Continuous-time Perturbed Takagi-Sugeno Fuzzy Models: Application to Ship Steering Systems

Wen-Jer Chang,Yan-Horng Lin,Jialu Du,Chih-Ming Chang 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.10

The stability analysis and controller design of stochastic systems have become much more important because the stochastic behaviors usually exist in practical nonlinear systems. In this paper, a robust fuzzy controller design approach is proposed with multiple constraints, including state variance constraints, output variance constraints, and pole placement constraints. At first, nonlinear systems are expressed as the Takagi-Sugeno fuzzy model, and the parallel distributed compensation method is applied to design the robust fuzzy controllers. Next, considering the stability analysis and the performance constraints of perturbed Takagi-Sugeno fuzzy models, Lyapunov conditions are developed based on covariance control theory, pole placement theory and robust control theory. By constructing the stability conditions with multiple constraints, the proposed fuzzy control problem can be effectively transferred into the linear matrix inequality problem. It can be solved by the convex optimal programming algorithm. At last, a nonlinear ship steering system is selected to verify the effectiveness and applicability of the proposed robust fuzzy controller design method.

Determination of spalling strength of rock by incident waveform

Tao, Ming,Zhao, Huatao,Li, Xibing,Ma, Jialu,Du, Kun,Xie, Xiaofeng Techno-Press 2017 Geomechanics & engineering Vol.12 No.1

An experimental technique for determining the spalling strength of rock-like materials under a high strain rate is developed. It is observed that the spalling strength of a specimen can be determined by only knowing the wavelength, loading peak value and length of the first spallation of an incident wave under a specific loading waveform. Using this method in combination with a split-Hopkinson pressure bar (SHPB) and other experimental devices, the spalling strength of granite specimens under a high strain rate is tested. Comparisons with other experimental results show that the new measuring method can accurately calculate the dynamic tensile strength of rock materials under a high strain rate.

Design and Implementation of Vision-Based Transport for a Mobile Robot via Kalman Filter

Shuanghe Yu,Yuqing Chen,Dan Wang,Jialu Du 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

In this paper, we propose a vision-based scheme for object recognition and transport with a mobile robot. At first, the camera calibration is experimentally performed with Zhenyou Zhang"s method. A distance measurement method with monocular camera is presented ant tested. And then the proposed scheme uses HSI model as the input and the seed filling algorithm as the image segmentation approach, a Kalman Filtering algorithm is used to predict the movement of the moving target. Finally, the motion control of the pan-tilt camera and mobile robot is designed to fulfill the tracking and transport task. The experiment results on a recognition and transport task have demonstrated the robust object recognition and fast tracking capabilities of the proposed scheme.