381 results about "Ship motions" patented technology

A method for a short-term prediction of future ship motion in open water to furnish visual cueing information that can be remotely presented to a pilot during an aircraft landing is described. Two sets of samples of the sea surface geometry along a radial azimuth line from a ship as a function of elevation of a sensor are first acquired. These are compensated to remove the components due to the ship's motion. Two wave traces are then separately derived in Cartesian format from the two sets of acquired samples. These wave traces are subjected to a Fast Fourier Transform to detect the amplitudes and phases of the individual wavelength components. The direction of the wavelength components is determined using a measure of their phase change in the scan direction during the time interval between the two scans together with their measured wavelength. The amplitude, direction and phase of each component is utilized together with the known motion characteristics of the moving ship in order to derive a short-term prediction of future ship motion in the time domain. A quiescent period of the ship motion is located by comparing the short-term prediction with the pre-defined operating limit criteria. Finally, a message signal is transmitted to the pilot of the aircraft indicating Time-to-Land and the duration of the quiescent period.

An offshore floating production, storage, and off-loading vessel has a hull of generally cylindrical or polygonal configuration surrounding a central double tapered conical moon pool and contains water ballast and oil and / or liquefied gas storage compartments. The exterior side walls of the polygonal hull have flat surfaces and sharp corners to cut ice sheets, resist and break ice, and move ice pressure ridges away from the structure. An adjustable water ballast system induces heave, roll, pitch and surge motions of the vessel to dynamically position and maneuver the vessel to accomplish ice cutting, breaking and moving operations. The moon pool shape and other devices on the vessel provide added virtual mass for increasing the natural period of the roll and heave modes, reducing dynamic amplification and resonance due to waves and vessel motion, and facilitate maneuvering the vessel. A disconnectable turret buoy at the bottom of the moon pool connects risers and mooring lines.

A motion control system for a ship has one or more sensors generating sea condition data and at least one ship control system. Analyzer software receives the sea condition data and predicts a sea condition event. Calculator software calculates one or more commands in preparation for the sea condition event. Interface software communicates the one or more commands to the at least one ship control system and the at least one ship control system implements a command in advance of the event. The at least one ship control system may comprise a ride control system having one or more motion control devices. The at least one ship control system may also comprise an auto pilot system.

This invention provides a global strategic picture of commodity movements generated by tracking ships from satellite and other sources and then combining ship location and movement information with at least one other data set, such as vessel, port, cargo, weather, or market data. Ship positions are integrated with other data, such as vessel, port, cargo, weather, and market information, to create a global strategic picture of commodity flows. A global strategic picture may then be generated by combining (i) ship movements gathered by satellite and other sources, with (ii) vessel, port, cargo, weather, market, and other data from existing sources, and (iii) a time history of these data sets.

A system and method of generating a landing trajectory for use in landing an aircraft onto a deck of a waterborne ship includes sensing motion of the ship, and sensing wind speed and wind direction. The sensed motion of the ship is processed to generate estimates of ship attitude and vertical speed, and the sensed wind speed and wind direction are processed to generate estimates of air-wake disturbances ahead of the aircraft. The landing trajectory is generated based on the estimates of ship attitude and vertical speed and the estimates of air-wake disturbances. The system and method implement model predictive control to calculate the control maneuvers multiple steps ahead, which provides the capability to smoothly control the timing of the aircraft touchdown phase.

The ship motion simulator as one integral electromechanical apparatus consists of a six-freedom motion platform and large hydraulic cylinder connected serially, and the experiment cabin is fixed to the top of the six-freedom motion platform supported by the large hydraulic cylinder. The present invention can simulate the motion of ship in sea based on the requirement of experiment. The two-stages composite motion simulator of the present invention has great motion range for simulating ship motion state of ship in 1-6 scale of sea state. After one sea state scale, say 6 scale, in the range is given, the control system will give the motion locus of ship in the said sea state, 6 scale of sea state and the simulating platform will move in the given locus under the drive of the hydraulically driven simulating platform.

The invention discloses a G-N wave model-based forecast method for a large-amplitude motion of a ship in a severe sea condition, and belongs to the technical field of ship motion forecast. Through nonlinear simulation of the motion of the ship in waves, a nonlinear effect of an incident wave force and a hydrostatic restoring force of a ship body is considered, and an incident wave pressure on thewet surface of the ship body is calculated. A fluid pressure is solved based on a G-N wave theory, so that the incident wave force and a hydrostatic pressure are obtained; a radiation force and a diffraction force are solved by adopting an impulse response function method, wherein the wave surface of the diffraction force is obtained by a G-N wave model; and consistency correction can be performedin calculation. The large-amplitude motion of the ship is forecast by adopting a weak nonlinear motion equation based on coupling of three freedom degrees including heaving, pitching and rolling; RAOis calculated for analyzing motion characteristics of the ship; a simulated motion response time history significant valve, a motion extremum value and oscillation statistics are analyzed by utilizing a wave-by-wave analysis theory; and the motion of the ship body can be forecast more accurately.

The present invention is typically embodied to exert active control of two same-shipboard cranes performing joint lifting of a payload. Sensory signals indicative of ship motion, and of luff angle and hoist line length of both cranes, are transmitted to a computer. The sensory signals are processed by the computer using a ship motion cancellation algorithm, which solves for values of the respective luff angles and hoist line lengths of both cranes, such values achieving static equilibrium (e.g., zero motion horizontally, vertically, and rotationally in the same vertical geometric plane) of the suspended payload. Inverse kinematic control signals in accordance with the mathematical (e.g., minimum norm) solutions are transmitted by the computer to respective luff angle actuators and hoist line length actuators of both cranes so that the suspended payload tends toward steadiness. Inventive control thus acts on a continual basis to significantly reduce pendulation during the two-crane lifting operation.

An apparatus for installing subsea components includes the use of a motion compensator to counterbalance and offset load on the component and lowering wire caused by movement of the vessel as a result of waves and wind.

The invention discloses a ship manoeuvring and main propulsion combination control method and a simulation system thereof, and relates to the technical field of ship control. According to course steering order and speed engine order of a ship driver, the control method achieves integrative combined control of factors such as general coordinated ship maneuverability, host performance characteristic, ship loading, marine environment disturbance, safe navigation, economic navigation and the like to motion of the ship and running of a propulsion host; and the simulation system verifies validity of the ship manoeuvring and main propulsion combination control method. The control method and the simulation system have the advantages of improving integral economical efficiency and maneuverability of a ship system, improving control effect on motion of the ship, facilitating safe navigation of the ship, preventing a diesel host from overloading, and improving reliability and economical efficiency of a power device.

The invention belongs to the technical field of automatic ship anti-collision route planning and mainly relates to an automatic ship anti-collision method optimized by a wolf colony search algorithm. The method disclosed by the invention comprises the following steps: establishing a simulation interface needed by a ship simulation test, and determining ship parameters used for collision avoidance; and determining ship encounter situation and analyzing collision risk index, namely adopting the across encounter situation of two ships, analyzing the collision risk index shown in the specification of the ship and a target ship, wherein UtT is the time-based collision risk index, UdT is the space collision risk index, and only when UtT and UdT are not zero, ship collision risk exists. According to the method disclosed by the invention, the defect that the rate of convergence is reduced because the wolf colony algorithm crosses the border in the migrating, moving and surrounding processes when exceeding the search space is overcome, the improved algorithm is applied to automatic ship anti-collision route planning, and an automatic ship anti-collision method optimized by the wolf colony search algorithm is generated through establishment of a ship motion model and generation of the objective function.

The invention discloses a dynamic ship monitoring information system, in which an AIS transmitter is arranged on a ship, an AIS receiver is connected with a monitoring server which is connected with a client terminal by a communication network which is internally provided with an operation processor and a memory which is used for memorizing the AIS ship information and electronic chart data. The realization method of the invention comprises the steps as follows: a matching data module is established; the ship information is called out of the AIS data module; whether the ship motion state and a triggering rule are matched or not is compared; the proportion of the chart is calculated; an electronic chart data module is called according to the proportion and the position so as to generate a local electronic chart background module; ship drawings are laminated on the local electronic chart background module so as to obtain a local ship chart; a data module to be informed is turned to; a sending path is selected and the local ship chart is sent to the client terminal. The dynamic ship monitoring system can conveniently calculate the local ship electronic chart, to which the ship the client pays attention, and transmit the local ship electronic chart to the client terminal, thus bringing intuitionistic dynamic ship information for the clients.

A ship motion prediction system is described that includes a plurality of surface platforms and a central computer having a communications interface. The platforms each include a propulsion system for movement of the platform, a plurality of sensors operable for gathering sensor data relating to an environment proximate the platform, a processing device communicatively coupled to the propulsion system and the plurality of sensors, and a transceiver communicatively coupled to the processing device. The central computer includes a communications interface, and the processing device is programmed to transmit sensor data to the central computer via the transceiver and the communications interface. The central computer is programmed to transmit commands for operation of the propulsion system to the processing device via the communications interface and transceiver. The central computer is further programmed to predict an effect of the environments associated with the plurality of surface platforms on a water vessel or vessels operating within a vicinity of the plurality of surface platforms.

The invention provides a ship motion control system with control input restraints considered. The ship motion control system comprises a guide system, a control system, a sensor system, a differential homeomorphism convertor and a data processing system and further comprises an input compensation system. The guide system calculates the expected pose and the expected speed of a ship at each moment according to the input expected value and the initial position of the ship; a sensor collects actual pose information and actual speed information of the ship; the data processing system obtains low-frequency pose information and the low-frequency speed of the ship; the differential homeomorphism convertor obtains new state variables; the control system conducts corresponding solution according to the new state variables to obtain corresponding control instruction information; the control instruction information is transmitted to the input compensation system to be compensated, and a final control instruction is obtained and sent to an execution mechanism of the ship. According to the ship motion control system, a model has an unknown non-linear function, the control input restraints are considered, and the ship motion control system is designed on the basis of self-adaption neural network estimation and through the filtering back-stepping method.

There is disclosed a predictive filter for predicting the future position of a look direction of a rotating directional antenna mounted on a vessel. Prediction of a look direction of the antenna at any instant is made from input of ship's compass data including roll data, pitch data and heading data, as well as data describing a rotational position of the antenna, output from an antenna synchro device. Smoothing of the digital roll, pitch and heading data and antenna position data is followed by application of a moving time window, filter which removes any offset from the data within of the moving time window to produce data having a zero mean. The zero mean data is input into an auto-regression algorithm, the output of which is combined with mean roll, pitch, heading, position and antenna velocity data to obtain predicted positions of the antenna relative to the vessel, and a predicted motion of the vessel. The combined vessel motion prediction and antenna position and velocity prediction can be used to establish a predictive future look direction of the antenna for a period of between 0.1 and 5 seconds into the future.

The invention relates to an auxiliary carrier landing guiding and display system used for an unmanned helicopter. The auxiliary carrier landing guiding and display system is distinguished from a conventional unmanned plane carrier landing information display system in that flight state information of the unmanned helicopter is contained, and ship motion state information and carrier landing landmark position information are also contained, so that the auxiliary carrier landing guiding and display system is capable of assisting operation personnel of an unmanned plane ground control station to sense the situation of the unmanned helicopter in all directions, and safe carrier landing operation is further completed. In addition, auxiliary carrier landing guiding information is expressed by symbols, so that a display interface of the ground station is clearer and simpler, the display content is more visual, and the human-computer interface is friendly. By means of simple transformation, the auxiliary carrier landing guiding and display system can be applied to carrier landing of the unmanned helicopter.

The invention relates to a ship position motion test platform, which comprises upper and lower layers which make two-dimensional translation, wherein the upper and lower layers are controlled by a motion lock to make relative motion, and a position sensor, a compass and a global positioning system (GPS) are installed on a central platform; a sea condition simulation computer receives current sea conditions input by a keyboard, calculates and simulates the impact of external interference on a ship position and sends a two-dimensional translation command to control the lower layer to be used for simulating the sea conditions, and a ship motion console issues corresponding control commands to a rudder and a side thruster according to the detected ship position; and a ship model computer receives the commands issued by the ship motion console, obtains the current rubber angle and the position of a ship under the action of the side thruster by calculation, issues the two-dimensional translation commands to control the upper layer to move relative to the lower layer, issues rotating commands to control the central platform to rotate, and simulates the deflection of the ship under the action of the side thruster at the current rudder angle. In the ship position motion test platform, the ship parameters and the sea conditions can be arbitrarily set to realize the semi-physical simulation test of the dynamic positioning and automatic berthing or unberthing of the ship.

The invention relates to a force analysis method of a single point buoy mooring system of an extra-large ship under the coupling action of stormy waves and provides a mooring force mathematical model suitable for a single point buoy anti-typhoon mooring system of the extra-large ship, which are used for performing identification modeling on a non-steady motion strained condition under a typhoon environment and performing a mathematical simulation test and actual measurement verification on the force motion of the ship without power and interference effects of the typhoon environment. Required input and output data are provided for the identification modeling of the mathematical model through a ship motion physical model test of a single point mooring ship model under the action of wind, currents and waves; and a mooring curve of a buoy type anti-typhoon single point mooring system is deduced and the influence of all component parts on the mooring curve is analyzed by researching a ship-buoy motion law based on catenary and cubic parabola theories, so that the key technical problem of the design of the single point buoy anti-typhoon mooring system is solved.

The invention discloses a hardware in-loop simulation system for comprehensive optimization control of main power and manipulation of a ship. The system comprises a virtual ship motion simulation system, a ship main power and manipulation comprehensive optimization controller, a ship steering and main engine console, a ship monitoring simulation system, a system scheduling server and an Ethernet, wherein the virtual ship motion simulation system, the ship main power and manipulation comprehensive optimization controller, the ship monitoring simulation system and the system scheduling server exchange data with each other through the Ethernet respectively; and the ship main power and manipulation comprehensive optimization controller is directly connected with the ship steering and main engine console through analogue level. Because a user of the invention can set different ship parameters such as length of the ship, draft and block coefficient and sea condition parameters such as wind wave strength, direction and the like on a user interface provided in the ship monitoring simulation system as required, the control simulation effects of various types of ships under various sea conditions can be simulated.

A motion compensation method and system is included in a radar antenna system mounted on a moving platform which is subject to pitch, yaw and roll. The radar antenna system includes a main array antenna, and an auxiliary antenna. The auxiliary channel associated with the auxiliary antenna utilizes roll, pitch and yaw angle motion compensations as its auxiliary antenna always steers a horizontal fan shape beam at the horizon to blank any surface (land or sea) based EM interferences. Such motion compensations are provided by a ship motion compensator component and process included within the antenna system. The ship motion compensator component in response to platform motion signals indicative of changes in platform motion angles generates new sets of values using an initial set of weighting coefficient values as a function of such angle motion changes. This produces changes in both amplitude and phase weighting coefficient values which results in both the quadrant phase rotation and the element weighting rotation. The process steers and spreads out the received auxiliary antenna pattern making sidelobe coverage broad enough to compensate for such changes in platform motion.

The invention is directed to a tensioner / slip-joint module for providing a conduit from a floating vessel at the surface of the ocean to the blowout preventer stack, or production tree, which is connected to the wellhead at the sea floor. The tensioner / slip-joint module compensates for vessel motion induced by wave action and heave and maintains a variable tension to the riser string alleviating the potential for compression and thus buckling or failure of the riser string. The tensioner / slip-joint module of the present invention preferably includes at least one mandrel having at least one hang-off donut; at least one upper flexjoint swivel assembly, at least one radially ported manifold, at least one tensioning cylinder, and at least one slip-joint assembly combined in a single unit.

The invention discloses a method for improving the display speed of ship motion tracks on an electronic navigation chart client. The method comprises the steps of: dividing a display scale of an electronic navigation chart into different levels, wherein each level corresponds to one display scale range; presetting a data compression threshold for each display scale level; utilizing a vector data compression method to mark the display scale level for each position point in the ship motion track, wherein a scale is larger and corresponding ship motion track points are more; and only downloading data of the ship motion track points which are positioned in the geographical range displayed by the navigation chart of the client or the properly amplified range and correspond to the display scale of the navigation chart of the client from a server and displaying the data by the client. Through the method, when a user performs the display of the ship motion tracks on the electronic navigation chart client, only a less amount of ship track data is downloaded and displayed, which can effectively improve the download and display speed of the ship track data.

The invention discloses an unmanned ship heading and speed cooperative control method based on a fuzzy adaptive algorithm. In order to solve the problems that in a conventional control method, a motion model is hard to accurately determine, the dynamic response is not ideal, and the anti-jamming capability is low, the fuzzy control algorithm is adopted for improving the fitness of a USV control method under undetermined water conditions, and the ship motion modeling problem in the conventional method is solved. The two-input and two-output improved USV fuzzy control algorithm is put forwards, a range ambiguity domain function is added to serve as the algorithm input, the heading and the speed are brought into the autonomous control range to conduct cooperative control, the convergence rate of USV motion control is increased, and the control robustness is improved; the course angle deviation ratio is adopted as the measurement of the operation environment uncertainty and the running state deviation degree, interval parameters are adjusted and controlled automatically, the control algorithm can adjust control parameters in a self-adaptive mode according to the control environment change, , and the intelligence of an autonomous control system is further improved.

The invention relates to a ship motion control algorithm test simulation system, which consists of a ship model setting and testing module, a control algorithm loading and testing module, a ship motion mathematical model module, a ship course and path curve display interface and a ship motion virtual reality simulation scene. The ship model setting and testing module and the control algorithm loading and testing module are in two-way data connection with the a ship motion mathematical model module; the ship motion mathematical model module transmits data to the ship course and path curve display interface and the ship motion virtual reality simulation scene unidirectionally; and the ship course and path curve display interface and the ship motion virtual reality simulation scene can transmit data to the ship model setting and testing module, and the control algorithm loading and testing module unidirectionally. The simulation system brings convenience to the improvement of control algorithm, reduces the frequencies of sea trial and the experimental cost, shortens the development cycle and accelerates the application of advanced control theories in practical engineering.

The invention provides a ship trajectory prediction method and system based on an LSTM automatic encoder and a bidirectional LSTM, and the method comprises the steps: carrying out the preprocessing ofship AIS trajectory data, and carrying out the feature extraction of the trajectory data through an automatic encoder; then, combining the extracted features with trajectory longitude and latitude data to represent the current navigation state of the ship; and taking the extracted features with trajectory longitude and latitude data as model input, learning a ship motion law implied in the trajectory data through a bidirectional LSTM neural network model containing an attention mechanism, and predicting the position of the ship at the next moment by using the ship motion law learned by the model. According to the method, the ship track prediction is carried out by adopting a scheme of the LSTM automatic encoder, the attention mechanism and the bidirectional LSTM neural network, and the bidirectional LSTM model can better mine the space-time association relationship of the track data on the premise of reserving enough effective information of the ship track data. According to the method, the trajectory prediction precision can be effectively improved, the real-time prediction is realized, and the requirement of a scene with relatively high trajectory prediction timeliness and accuracy is met.

The invention discloses a ship water power online forecast based ship shake reduction control system, and belongs to the technical field of ship and ocean engineering. Online self-adaption forecast ofship water power can be achieved according to a water power equation on the basis of the ship motion parameter real-time forecast and dynamic balancing idea and can be used as a basis of shake reduction control. A sensor module can measure the ship motion parameter, and a water power online estimation module and a fin angle allocation module can perform real-time self-adaption control on ship motion; and compared with the conventional shake reduction control method, the self-adaption and a water power estimation model are more perfect. The ship shake reduction system can be arranged on shipswith single-pair fins or dual-pair fins, can achieve horizontal shake reduction and vertical shake reduction of the ships with single-pair fins, can achieve horizontal shake reduction and vertical shake reduction, and vertical-horizontal shake reduction of the ships with dual-pair fins, can be widely used for shake reduction control of various water ships, and has good application prospect and good economic benefits in the field of ship shake reduction control.

The invention provides a ship safety assisted driving system based on ship motion prediction, wherein a ship motion data acquisition system acquires the ship's motion attitude data in real time; an environment perception and acquisition system collects the navigation environment information of the ship; a ship motion prediction and calculation unit calculates and predicts the trajectory of the ship in the next week in real time according to the ship's motion attitude data, and generates a ship motion prediction line; a ship motion trajectory navigation display system reconstructs the navigation environment information collected by the environment perception and acquisition system, and superimposes and displays the ship motion prediction line; and a ship safety assisted decision-making system calculates and estimates the ship safety index parameters based on the surrounding environment and motion prediction, and provides safety warning and operational recommendations. The ship safety assisted driving system provided by the invention, based on ship motion prediction and dynamic scene capture, displays the motion prediction line of the ship on the navigation aid display of the cab, assists the driver to make maneuver decisions, and improves the safety of the ship sailing and the port by berthing.

The invention provides a dynamic positioning simulation test platform and a position control method. The dynamic positioning simulation test platform comprises a ship motion simulation computer (7), a three degree-of-freedom horizontal motion platform (8), a four degree-of-freedom motion rotary table (9), a data processing computer (4), a comprehensive display and control computer (6), a compass (1), a global position system (GPS) (2), and a mobile radio unit (MRU) (3), wherein the data processing computer (4), the ship motion simulation computer (7), the three degree-of-freedom horizontal motion platform (8), and the four degree-of-freedom motion rotary table (9) are connected to form a local area network through Ethernet, the four degree-of-freedom motion rotary table (9) is installed on the three degree-of-freedom horizontal motion platform (8), the compass (1), the GPS (2), and the MRU (3) are all installed on the four degree-of-freedom motion rotary table (9) and are connected with the data processing computer (4) through serial interfaces, and a data fusion algorithm (5) is loaded in the data processing computer (4). The dynamic positioning simulation test platform and the position control method can be used for simulating six degree-of-freedom motion of ships.