scholarly journals Modeling and Identification of Podded Propulsion Unmanned Surface Vehicle and Its Course Control Research

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Dongdong Mu ◽  
Guofeng Wang ◽  
Yunsheng Fan ◽  
Yongsheng Zhao

The response model of podded propulsion unmanned surface vehicle (USV) is established and identified; then considering the USV has characteristic of high speed, the course controller with fast convergence speed is proposed. The idea of MMG separate modeling is used to establish three-DOF planar motion model of the podded propulsion USV, and then the model is simplified as a response model. Then based on field experiments, the parameters of the response model are obtained by the method of system identification. Unlike ordinary ships, USV has the advantages of fast speed and small size, so the controller needs fast convergence speed and strong robustness. Based on the theory of multimode control, a fast nonsingular terminal sliding mode (FNTSM) course controller is proposed. In order to reduce the chattering of system, disturbance observer is used to compensate the disturbance to reduce the control gain and RBF neural network is applied to approximate the symbolic function. At the same time, fuzzy algorithm is employed to realize the mode soft switching, which avoids the unnecessary chattering when the mode is switched. Finally the rapidity and robustness of the proposed control approach are demonstrated by simulations and comparison studies.

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7454
Author(s):  
Yunsheng Fan ◽  
Bowen Liu ◽  
Guofeng Wang ◽  
Dongdong Mu

This paper focuses on an issue involving robust adaptive path following for the uncertain underactuated unmanned surface vehicle with time-varying large sideslips angle and actuator saturation. An improved line-of-sight guidance law based on a reduced-order extended state observer is proposed to address the large sideslip angle that occurs in practical navigation. Next, the finite-time disturbances observer is designed by considering the perturbations parameter of the model and the unknown disturbances of the external environment as the lumped disturbances. Then, an adaptive term is introduced into Fast Non-singular Terminal Sliding Mode Control to design the path following controllers. Finally, considering the saturation of actuator, an auxiliary dynamic system is introduced. By selecting the appropriate design parameters, all the signals of the whole path following a closed-loop system can be ultimately bounded. Real-time control of path following can be achieved by transferring data from shipborne sensors such as GPS, combined inertial guidance and anemoclinograph to the Fast Non-singular Terminal Sliding Mode controller. Two examples as comparisons were carried out to demonstrate the validity of the proposed control approach.


Author(s):  
Guo Pengfei ◽  
Liang Zhenying ◽  
Wang Xi ◽  
Jin Zengke

In this paper, the fixed-time stabilization problem for a class of uncertain chained system is addressed by using a novel nonsingular recursive terminal sliding mode control approach. A fixed-time controller and an adaptive law are designed to guarantee the uncertain chained form system both Lyapunov stable and fixed-time convergent within the settling time. The advantage of the controller based on the sliding mode is that the settling time does not depend on the system initial state. Furthermore, we use RBF neural network to estimate the uncertainty of the system. Finally, the simulation results demonstrate the performance of the control laws.


2014 ◽  
Vol 898 ◽  
pp. 514-520 ◽  
Author(s):  
Chang Kai Xu ◽  
Ming Li ◽  
Jian Yin

In this paper, a neural network sliding mode controller for a kind of 5DOFs robotic manipulator is proposed. A radial basis function (RBF) neural network is used as an estimator to approximate uncertainties of the system. The learning algorithm of the neural network improves the performance of the system. A globle terminal sliding mode control (GTSMC) is designed to guarantee the stability and improve the dynamic performance of the robotic manipulator. Simulation results show that the proposed NNSMC strategy is effective to ensure the robustness and dynamic performance of the 5DOFs robotic manipulator.


2019 ◽  
Vol 2019 ◽  
pp. 1-17
Author(s):  
Jingshuai Huang ◽  
Hongbo Zhang ◽  
Guojian Tang ◽  
Weimin Bao

For the terminal guidance problem of a missile intercepting a maneuvering target, a profile-tracking-based adaptive guidance law is proposed with inherent continuity in this paper. To flexibly and quantitatively control the convergence rate of the line-of-sight rate, a standard tracking profile is designed where the convergence rate is analytically given. Then, a nonsingular fast terminal sliding-mode control approach is used to track the profile. By estimating the square of the upper bound of target maneuver, an adaptive term is constructed to compensate the maneuver. Therefore, no information of target acceleration is required in the derived law. Stability analysis shows that the tracking error can converge to a small neighborhood of zero in finite time. Furthermore, a guidance-command-conversion scheme is presented to convert the law into the one appropriate for endoatmospheric interceptions. Simulation results indicate that the proposed law is effective and outperforms existing guidance laws.


Author(s):  
Xin Zhang ◽  
Ran Shi

Aiming at the manipulator control system is susceptible to model parameter uncertainty and external disturbance. In this article, an adaptive non-singular fast terminal sliding mode control based on variable exponential power reaching law is proposed. First, due to the slow convergence speed and large chattering of the traditional reaching law, the variable exponential power reaching law is designed in this article. It can adaptively change the reached speed according to the system state, improve the accuracy of the control system and reduce chattering. Second, compared to the slow convergence speed of traditional sliding mode surfaces, this article uses non-singular fast terminal sliding mode surfaces to speed up the system error convergence speed. At the same time, in view of the problem that the disturbance has an uncertain upper bound in the actual problem, the adaptive law is used to estimate the uncertain upper bound of the system disturbance. And by introducing a time-varying boundary layer to improve the symbolic function in the control law. Finally, the Lyapunov function is used to prove the stability of the control system. The simulation results show that the controller designed in this article has good position tracking performance and strong anti-disturbance ability.


Author(s):  
To Xuan Dinh ◽  
Kyoung Kwan Ahn

This article proposed a variable gain fast terminal sliding mode controller with an estimator of the uncertainty model for a piezo positioning stage system. The designed terminal sliding mode control has some advantages over the linear sliding mode control such as fast convergence and chattering reduction while maintains its robustness to the uncertainties. Next, an indirect technique is developed to enable the elimination of the singularity problem corresponding to initial terminal sliding mode control. In addition, a cerebellar model articulation controller is carried out to estimate the nonlinear dynamics of the piezo positioning stage. To deal with unknown bounds of uncertainties and disturbances, the proposed scheme consists of using online tuning control gains that ensure the establishment of a real terminal sliding mode in a finite time. Moreover, a fuzzy logic scheme is presented to smooth out the discontinuity part of the control signal, hence improve the control performance. Stability analysis of closed loop system is provided using the Lyapunov function method. Experiment results are presented to evaluate the effectiveness of the designed control approach.


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