Fuzzy logic control, due to its simple control structure, easy and cost-effective design, has been successfully employed to the application of guidance and control in robotic fields. This paper aims to review fuzzy-logic-based guidance and control in an important branch of robots—marine robotic vehicles. First, guidance and motion forms including the maneuvering, path following, trajectory tracking, and position stabilization are described. Subsequently, the application of three major classes of fuzzy logic control, including the conventional fuzzy control (Mamdani fuzzy control and Takagi–Sugeno–Kang fuzzy control), adaptive fuzzy control (self-tuning fuzzy control and direct/indirect adaptive fuzzy control), and hybrid fuzzy control (fuzzy PID control, fuzzy sliding mode control, and neuro-fuzzy control) are presented. In particular, we summarize the design and analysis process of direct/indirect adaptive fuzzy control and fuzzy PID control in marine robotic fields. In addition, two comparative results between hybrid fuzzy control and the corresponding single control are provided to illustrate the superiority of hybrid fuzzy control. Finally, trends of the fuzzy future in marine robotic vehicles are concluded based on its state of the art.

Survey on Fuzzy-Logic-Based Guidance and Control of Marine Surface Vehicles and Underwater Vehicles

Prerequisites to the successful application of the H∞ control design technique to the marine dynamic positioning (DP) control problem are a realistic nominal model, relative bounds on modelling uncertainty, a set of frequency-dependent weighting functions to translate the control design specification into a control solution and a performance index to quantify the robustness. The authors propose procedures and algorithms to achieve these objectives. The H∞ robust control design technique is then used to calculate a robust controller which has superior properties to the conventional DP systems. The trade-off between track keeping and station keeping is undertaken via appropriate weighting functions and a two-degree-of-freedom control structure is employed. The technique proposed shows that effective wave filtering can be obtained with guaranteed stability robustness. The advantage of the proposed control design technique is demonstrated using ship nonlinear simulations.

H∞ robust control design for dynamic ship positioning : Special section on marine control

Adaptive fuzzy output-feedback control for output constrained nonlinear systems in the presence of input saturation

At present, with the development of waterborne transport vehicles, research on ship faces a new round of challenges in terms of intelligence and autonomy. The concept of maritime autonomous surface ships (MASS) has been put forward by the International Maritime Organization in 2017, in which MASS become the new focus of the waterborne transportation industry. This paper elaborates on the state-of-the-art research on motion control of MASS. Firstly, the characteristics and current research status of unmanned surface vessels in MASS and conventional ships are summarized, and the system composition of MASS is analyzed. In order to better realize the self-adaptability of the MASS motion control, the theory and algorithm of ship motion control-related systems are emphatically analyzed under the condition of classifying ship motion control. Especially, the application of intelligent algorithms in the ship control field is summarized and analyzed. Finally, this paper summarizes the challenges faced by MASS in the model establishment, motion control algorithms, and real ship experiments, and proposes the composition of MASS motion control system based on variable autonomous control strategy. Future researches on the accuracy and diversity of developments and applications to MASS motion control are suggested.

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State-of-the-Art Research on Motion Control of Maritime Autonomous Surface Ships

The backstepping control is a kind of nonlinear controller design algorithm. To simplify the nonlinear controller design process, decrease the number of undetermined parameters, improve the robustness, and reduce the energy consumption of the course-keeping controller for ships, an improved concise design method is proposed by introducing an arctan nonlinear function passed through by course error signal under the backstepping design framework, while the design process of the controller is simplified to only one step. The simulation results indicate that, compared with the backstepping-based controller, the maximum response performance (quantified by the mean absolute error) under the proposed controller increases by 57.8%, the maximum energy cost performance (quantified by the mean integral absolute) reduces by 28.6% and the maximum smoothness performance (quantified by the mean total variation) reduces by 44.3% with the strong ability of disturbances rejection. The algorithm given in the note has advantages of the simple design process, strong robustness, and low energy consumption.

/pdf/nonlinear-improved-concise-backstepping-control-of-course-19tr65dx1q.pdf

Nonlinear Improved Concise Backstepping Control of Course Keeping for Ships

In this article, a sliding mode control scheme for the autopilot system of a ship is presented, which also incorporates actuator saturation. Under the designed controller, the actuator doesn’t ente...

https://journals.sagepub.com/doi/pdf/10.1177/1729881417703568

Sliding mode control design of a ship steering autopilot with input saturation

In this paper, an optimal control scheme is presented for a ship in the presence of external disturbances. Using the backstepping technique and a disturbance observer method, a nonlinear control sc...

Optimal backstepping control for a ship using firefly optimization algorithm and disturbance observer

In this article, a MIMO autopilot control for a marine vessel has been designed such that it can perform well in the presence of input saturation and external disturbances. In order to tackle input saturation, a method based upon fuzzy logic is presented. Fuzzy logic ensures that the control input doesn't enter saturation mode. A disturbance observer (DO) has been used to estimate the external disturbance and remove its effects from the system. All these methods are amalgamated with a backstepping control scheme. The stability of the disturbance observer based backstepping control with anti-saturation via fuzzy logic has been proved via Lyapunov stability criteria. For validation of the proposed controller, numerical simulation is performed on a model ship named Cybership II. In addition, the simulation results of the proposed controller are compared with the traditional backstepping and PID controllers. The effectiveness of the proposed control methodology can be inferred from these results.

Disturbance observer based backstepping MIMO control design for a marine vessel in the presence of input saturation and external disturbance

This paper proposes an idea about the quadrotor unmanned aerial vehicles (UAVs) flying formation reconfiguration with collision avoidance and computation of the probabilistic roadmap (PRM) navigation method for nonlinear quadcopter model in dynamic environment. The safe zone and dangerous zone strategy have been adopted to reach the target position. A novel algorithm using probabilistic roadmap is proposed for collision avoidance. Two dimensional PD controllers are proposed for better path tracking and stability. The complete model of this system is simulated in MATLAB/Simulink. The response of path tracking, collision avoidance and flying formation of each UAV are discussed in detail. Results highlight the collision avoidance depends upon a total number of nodes and distance between two consecutive nodes according to the roadmap.

Muhammad Ejaz

Papers

Sliding mode control design of a ship steering autopilot with input saturation

Optimal backstepping control for a ship using firefly optimization algorithm and disturbance observer

Disturbance observer based backstepping MIMO control design for a marine vessel in the presence of input saturation and external disturbance

Quadrotor UAVs Flying Formation Reconfiguration with Collision Avoidance Using Probabilistic Roadmap Algorithm

Miniaturized frequency selective surface with high angular stability