The invention discloses a four-rotor aircraft fault-tolerant control method and belongs to the field of aerocraft control. According to the method, first, based on a mathematical model of an aircraft, an attitude model under the condition of system faults of the aircraft is established; then, according to the attitude model, an adaptive law of fault estimation of an aircraft system is brought out, and a transfer function of loss of actuator effectiveness of the aircraft is also established; an adaptive law of fault estimation of loss of actuator effectiveness is put forward based on the loss of actuator effectiveness; and at last, based on the fault estimation of the system and the fault estimation of loss of actuator effectiveness, a fault-tolerant controller of an aircraft attitude system is designed. Thus, fault-tolerant control of four-rotor aircrafts is realized. By means of the method, probability of air crashes of four-rotor aircrafts is remarkably reduced, and flying reliability and safety of aircrafts are improved.

Four-rotor aircraft fault-tolerant control method

The invention discloses an intelligent rudder system and a control method thereof; the system comprises a programmable automatic controller, a combined navigator, a propelling system device, a control system device and an emergency operation device. The method comprises the steps that: (1) the global positioning system (GPS) navigator and a three-dimensional electronic compass combined navigator which are arranged on a ship body are used for detecting the actual position and the course of the ship; (2) the programmable automatic controller converts and extracts characters, and then accounts the position, processes the course and computes a yaw angle; (3) the yaw distance d and the yaw angle Psi of the ship are computed; (4) whether the ship deviates or not is judged; and (5) the navigating state of the ship body at the next moment is detected, Step (1) is returned to, and the real-time closed-loop control is realized. The invention adopts a secondary gear to carry out reducing transmission, so that the operation precision of a rudder angle is improved. A host controller and a relay are adopted to timely control the propelling system and the control system, so that the sailing risks of the ship can be greatly reduced, and the intelligent steering stability when the ship is sailed is improved.

Intelligent rudder system and control method thereof

The invention provides an intelligent control method of a navigational speed of a ship. According to the intelligent control method, a given navigational speed is compared with an actual navigational speed measured by a navigational speed measuring device on the ship and an acquired navigational speed error is sent to a conventional PID (Proportional Integral Derivative) controller and a cerebellar model neural network; the conventional PID controller is used for control when a ship navigational speed control system runs; a control signal Up is output by the conventional PID controller to a navigational speed follow-up system till the navigational speed error becomes zero; the cerebellar model neural network in the ship navigational speed control system is of feed-forward control and used for realizing an inverse dynamic model of a controlled object; and at the end of each control period, a weight value of the cerebellar model neural network is adjusted by a learning algorithm based on a difference value between a total output navigational speed control signal U and an output signal Uc of the cerebellar model neural network. According to the invention, the advantages of the PID controller, such as simple design and definite physical significance, and the advantages of the cerebellar model neural network, such as strong nonlinear mapping capability, excellent instantaneity and strong robustness can be exerted very well, thereby endowing the ship navigational speed control system with more excellent control performance.

Intelligent control method of navigational speed of ship

The invention discloses a fault-tolerant control method for a networked control system with time-varying delay. In view of conditions of parameter perturbation, time-varying delay, external disturbance and random failure happening to an actuator, a discrete time closed-loop nonlinear networked control system model is firstly built, a Lyapunov-Krasovskii function with the delay information is then built, a Lyapunov stability theory and a linear matrix inequality analysis method are used, sufficient condition for asymptotic stability of the nonlinear networked control system and existence of an H-infinity fault-tolerant controller are obtained, a Matlab LMI toolbox is used for solution, and a gain matrix for a non-fragile fault-tolerant controller is: K=K P; and conditions for optimizing the minimum disturbance rejection rate gamma is given, and the controller gain matrix K optimized under the minimum disturbance rejection rate gammamin= square root of e is acquired. The condition of time-varying delay existing in the system is considered, the time-varying delay is analyzed and processed based on a free-weighting matrix method, and the conservation is reduced.

Fault-tolerant control method for networked control system with time-varying delay

A T-shaped hydrofoil capable of changing wing area and aspect ratio comprises a column, a horizontal main wing and extensible auxiliary wings. The upper end of the column is fixed at the hull bottom, and the lower end thereof is connected with the horizontal main wing. When needed, the auxiliary wings are pushed out from auxiliary wing tanks of the horizontal main wing by the aid of hydraulic oil cylinders, so that larger wing area and higher aspect ratio are obtained, lift coefficient is increased, and effects of restraining pitching and heaving are enhanced; when not needed, the auxiliary rings are recovered into the horizontal main wing by the aid of the hydraulic oil cylinders so as to reduce resistance, and accordingly fuel can be saved while speed is increased.

Hydraulically-driven variable-area T-shaped anti-rolling hydrofoil

The invention provides a path deviation generation analysis method for a ship at sea, which comprises the following steps of: (1) inputting longitude and latitude coordinates Q (xq, yq and zq) of a place of a departure, longitude and latitude coordinates M (xm, ym and zm) of a destination; (2) computing an expected optimum path; (3) correcting the expected path in segments; (4) computing the deviation between the ship and the path section; (5) judging whether the ship is in the current path section; and (6) if so, repeating the step (4), otherwise conducting the calculation of the next path section, and repeating the step (4). The path obtained by the invention can realize more economic and safer sailing, is beneficial to navigation, brings great convenience for autopilot sailing only by increasing shorter sailing distance, is also beneficial to path control, and also improves the control precision of paths.

Path deviation generation analysis method for ship at sea

The invention provides a ship course intelligent coordination control method which comprises the steps of: 1, setting an expected course angle; 2, calculating a deviation of a real course angle and the expected course angle; 3, obtaining a tilt control command signal; 4, calculating a course angle really output by a ship; 5, identifying a ship motion inverse system model, regulating parameters of a least square support vector machine; and 6, repeating the calculation of the step 2. By adopting a ship course compounding control measure combining inverse control with fuzzy control, the invention effectively overcomes the defect of inverse control caused by inaccurate identification of the inverse model based on input and output data, establishes a ship control inverse system model by adopting the least square support vector machine, has the advantages of simple structure design and high steady state accuracy, and can realize accurate control of course holding by combining with the advantages of rapid response, strong anti-interference capability and good robustness of the fuzzy control.

Ship course intelligent coordination control method

The invention provides an intelligent stepping fault-tolerance control method comprising the following steps of: (1) establishing a database of a robust fault-tolerance controller of a failure working condition; (2) dispatching and running a normal-operation working condition controller; (3) circularly checking and judging whether a signal exceeds a threshold value; (4) dispatching and running a passive-operation robust fault-tolerance controller; (5) diagnosing specific failure information of a system; (6) switching to a reconstructing fault-tolerance controller; and (7) repeating the step (3). The invention adopts the intelligent stepping fault-tolerance control method, organically combines robust passive fault-tolerance control with high real-time performance and poor performance and active fault-tolerance control with good performance and poor real-time performance, sufficiently exerts respective advantages, carries out the intelligent stepping fault-tolerance control of the system and reduces the real-time processing requirements and the difficulty of a system failure checking unit. Compared with the single passive and active fault-tolerance design, the invention has the advantages of simple structure, strong reliability, good real-time performance, strong universality, and the like and completely satisfies the requirements of engineering design.

Intelligent stepping fault-tolerance control method

The invention provides a multifunctional control device of a small waterline plane ship hydrofoil and column rudder, comprising two hydrofoils and a column rudder mechanism; each hydrofoil and the column rudder mechanism comprise hydrofoils; a hydrofoil strut fixed on the hydrofoil, two wing flaps symmetrically distributed on the hydrofoil and at the both sides of the hydrofoil strut and a columnrudder arranged on the hydrofoil strut; two hydrofoils and the column rudder mechanism are respectively installed at the front part and the rear part of a small waterplane area twin-hull ship; two sheet bodies of the hydrofoil and the small waterplane area twin-hull ship are fixedly connected according to a certain installation angle; the hydrofoil strut is fixedly connected with a connection body at the upper part of the small waterplane area twin-hull ship. The multifunctional control device of the invention has multiple functions, can shorten transient time from hullborne operation to foilborne operation, weaken heave motion and pitching motion of the small waterplane area twin-hull ship, weaken rolling motion of the catamaran, control inclination angle of the ship, has course control function, can effectively shorten steering gyration radius, and improve the safety, navigability and maneuverability of the small waterplane area twin-hull ship.

Multifunctional control device of small waterline plane ship hydrofoil and column rudder

The invention provides a drag-reducing device of a anti-rolling fin of a ship wing flap, comprising a fin and a wing flap, wherein one end of the fin is provided with a fin shaft; one end of the wing flap is provided with a wing flap fin shaft; the fin shaft and the wing flap fin shaft are connected with a ship hull; the upper fin surface at the free end of the fin is provided with an upper fin surface baffle, and the lower fin surface at the free end of the fin is provided with a lower fin surface baffle; the upper wing flap fin surface at the free end of the wing flap is provided with an upper wing flap fin surface baffle, and the lower wing flap fin surface at the free end of the wing flap is provided with a lower wing flap fin surface baffle The invention has simple structure and easy installation and realization and can effectively reduce the induced resistance of a fin stabilizer, enhance the lift efficiency of the anti-rolling fin of the wing flap, prevent a water flow medium cavitation phenomenon from generation and enhance the anti-rolling effect of the anti-rolling fin of the wing flap and the safety and the economy of ship navigation

Xucheng Chang

Papers

Path deviation generation analysis method for ship at sea

Ship course intelligent coordination control method

Intelligent stepping fault-tolerance control method

Multifunctional control device of small waterline plane ship hydrofoil and column rudder

Drag-reducing device of anti-rolling fin of ship wing flap