Simulator networking method, system and device based on data distribution service and medium

Abstract

The invention provides a simulator networking method, system and device based on data distribution service and a medium, and the method comprises the steps: determining all interface data needed by simulator networking according to an interface definition language determination rule, and obtaining an interface definition language file; generating a publishing and subscribing communication template program of the data distribution service in the data distribution service unit according to the interface definition language file in combination with an interface definition language template program generation tool; according to the interface definition language file, a simulator interface definition rule is combined, and a simulator interface program is generated; and mapping simulator interface data and data distribution network data according to the publish-subscribe communication template program and the simulator interface program. Simulator networking is achieved by mapping simulator interface data and data distribution network data in a modular mounting mode, the development process during networking function implementation is shortened, time delay and bandwidth consumption are reduced, and high efficiency and communication real-time performance during networking function implementation are improved.

Description

Technical Field

[0001] The present invention relates to the field of simulator networking technology, and in particular to a simulator networking method, system, device and medium based on data distribution service. Background Art

[0002] In the field of simulator networking technology, distributed network communication technology plays a key role when multiple simulators conduct flight formation training and collaborative combat simulation. It can ensure low latency and high reliability of data transmission, which is crucial to improving the realism of the simulation environment and the effectiveness of training. Current distributed network communication technologies usually involve architectures such as Distributed Interactive Simulation (DIS), High Level Architecture (HLA), and Data Distribution Service (DDS). However, due to the differences in the degree of implementation of DIS interface standards and HLA interface standards by different manufacturers, there are usually challenges in the interconnection of systems based on these standards from different manufacturers. In contrast, since the underlying layer of the DDS architecture uniformly adopts the Real-Time Publish Subscribe (RTPS) protocol, the DDS-based networking solution can more conveniently achieve interoperability between simulators.

[0003] There are two main DDS-based simulator networking methods. One method is to upgrade the simulator through the DDS middleware forwarding software to enable the simulator to have networking capabilities. The other method is to embed the DDS data interface directly into the simulator simulation software to realize the functional development and upgrade of the simulator simulation software, so that the simulator has networking capabilities. However, the former increases the time delay and bandwidth consumption of network communication and reduces the real-time performance of communication, while the latter requires the original platform code to be upgraded and compiled as a whole, which requires a large investment in manpower and time. The above shows that the current DDS-based simulator networking method is insufficient in terms of real-time communication or efficiency in realizing networking functions. Summary of the invention

[0004] The present invention provides a simulator networking method, system, device and medium based on data distribution service, which are used to solve the defects of the current simulator networking method based on DDS in terms of insufficient efficiency and real-time communication when realizing the networking function. It is realized without adding DDS middleware forwarding software and without upgrading and compiling the simulation platform code as a whole. Only by generating a simulator interface program and a simulator interface program according to an interface definition language file, the simulator interface data and the data distribution network data can be mapped to realize the simulator networking, shortening the development process when realizing the networking function, reducing time delay and bandwidth consumption, and thus improving the efficiency and real-time communication when realizing the networking function.

[0005] The present invention provides a simulator networking method based on data distribution service, comprising the following steps.

[0006] According to the interface definition language determination rules, all interface data required for the simulator to be connected to the network are determined, and an interface definition language file is obtained.

[0007] According to the interface definition language file and in combination with the interface definition language template program generation tool, a publish-subscribe communication template program of the data distribution service is generated in the data distribution service unit.

[0008] According to the interface definition language file and in combination with the simulator interface definition rules, a simulator interface program is generated in the data distribution service unit.

[0009] According to the publish-subscribe communication template program and the simulator interface program, the simulator interface data and the data distribution network data are mapped.

[0010] According to a simulator networking method based on data distribution service provided by the present invention, the publish-subscribe communication template program includes: a subscription class family publish-subscribe communication template program and a publishing class family publish-subscribe communication template program; according to the publish-subscribe communication template program and the simulator interface program, the simulator interface data and the data distribution network data are mapped, including: according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, the data distribution network data in the subscription class family is read, and the data distribution network data is written to the first pointer position in the simulator interface program; according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, the simulator interface data is read from the second pointer position in the simulator interface program, and the simulator interface data is written to the data distribution service network.

[0011] According to a simulator networking method based on data distribution service provided by the present invention, it also includes: in the data distribution service manager, instantiating the subscription class family as a first class object and instantiating the publishing class family as a second class object; passing the first pointer position corresponding to the simulator interface data to the first class object, and passing the second pointer position corresponding to the simulator interface data to the second class object; initializing the network status of the first class object and the second class object; when the initialization is completed and the network connection is established, updating the simulator interface data in the publishing class family.

[0012] According to a simulator networking method based on data distribution service provided by the present invention, the mapping result includes: a mapping relationship between the simulator and the data distribution service network, and a publish-subscribe relationship between the data distribution service unit and other functional simulation units of the simulator.

[0013] A simulator networking method based on data distribution service provided according to the present invention also includes: when the data distribution network data is status data, a fixed-frequency calling method is used to update the status data; when the data distribution network data is interactive data, an interrupt processing method is used to perform interrupt processing and solve the interactive data to obtain a solution result; and simulation is performed according to the solution result.

[0014] According to a simulator networking method based on data distribution service provided by the present invention, an interrupt processing method is adopted to perform interrupt processing and solving on interactive data to obtain a solving result, including: determining an interrupt request according to relevant information of the interactive data; when the interrupt request matches interrupt registration information, assigning the interactive data to interrupt data, and generating a target interrupt request carrying the interrupt data, the interrupt registration information is pre-registered in the interrupt trigger source system; according to the target interrupt request, triggering the corresponding interrupt registration information processing function, solving the interrupt data, and obtaining a solving result.

[0015] The present invention also provides a simulator networking system based on data distribution service, characterized in that it includes: a subscription class family, a publishing class family, a data distribution service unit and a data distribution service manager of the data distribution service; wherein the subscription class family is used to subscribe to the data distribution network data of the data distribution service network; the publishing class family is used to publish simulator interface data to the data distribution service network; the data distribution service unit is used to determine the publish-subscribe communication template program and the simulator interface program, the publish-subscribe communication template program is generated based on the interface definition language file and the interface definition language template program generation tool, and the simulator interface program is generated based on the interface definition language file and the simulator interface definition rule; the data distribution service manager is used to instantiate the subscription class family as a first type of object and instantiate the publishing class family as a second type of object; pass the first pointer position corresponding to the simulator interface data to the first type of object, and pass the second pointer position corresponding to the simulator interface data to the second type of object; initialize the network status of the first type of object and the second type of object; when the initialization is completed and the network connection is established, update the simulator interface data in the publishing class family. The subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program are determined based on the interface definition language file and the interface definition language template program, and the interface definition language file is determined based on the interface definition language determination rule.

[0016] The present invention also provides a simulator networking device based on data distribution service, comprising the following modules.

[0017] The file determination module is used to determine all interface data required for the simulator to be connected to the network according to the interface definition language determination rules, and obtain the interface definition language file.

[0018] The template program determination module is used to generate a publish-subscribe communication template program of a data distribution service in a data distribution service unit according to an interface definition language file and in combination with an interface definition language template program generation tool.

[0019] The interface program determination module is used to generate a simulator interface program in the data distribution service unit according to the interface definition language file and in combination with the simulator interface definition rules.

[0020] The data mapping module is used to map the simulator interface data and the data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0021] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements any of the above-mentioned simulator networking methods based on data distribution services.

[0022] The present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it implements any of the above-mentioned simulator networking methods based on data distribution services.

[0023] The present invention also provides a computer program product, including a computer program, which implements any of the above-mentioned simulator networking methods based on data distribution services when executed by a processor.

[0024] The present invention provides a simulator networking method, system, device and medium based on data distribution service, which determines all interface data required for simulator networking by determining rules according to interface definition language, and obtains interface definition language file; generates a publish-subscribe communication template program of data distribution service in data distribution service unit according to interface definition language file and interface definition language template program generation tool; generates a simulator interface program in data distribution service unit according to interface definition language file and simulator interface definition rules; maps simulator interface data and data distribution network data according to publish-subscribe communication template program and simulator interface program. The technical scheme of the present invention is used to solve the defects of the existing simulator networking method based on DDS in terms of high efficiency and communication real-time performance when realizing networking function, and realizes that there is no need to add DDS middleware forwarding software, and there is no need to upgrade and compile the simulation platform code as a whole. Only after generating simulator interface program and simulator interface program according to interface definition language file, simulator interface data and data distribution network data can be mapped to realize simulator networking, shortening the development process when realizing networking function, reducing time delay and bandwidth consumption, and thus improving the high efficiency and communication real-time performance when realizing networking function. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a scenario schematic diagram of a simulator networking method based on data distribution service provided by the present invention; Figure 2 It is a structural schematic diagram of the simulator networking system provided by the present invention; Figure 3 It is a flow chart of the simulator networking method based on data distribution service provided by the present invention.

[0027] Figure 4It is a structural schematic diagram of a simulator networking system based on data distribution service provided by the present invention.

[0028] Figure 5 It is a structural schematic diagram of a simulator networking device based on data distribution service provided by the present invention.

[0029] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to better understand the embodiments of the present invention, the background technology is first described in detail.

[0032] The current DDS-based simulator networking methods often include two methods. One method is to upgrade the simulator through the DDS middleware forwarding software to enable the simulator to have networking capabilities. The other method is to embed the DDS data interface directly into the simulator simulation software to realize the functional development and upgrade of the simulator simulation software, so that the simulator has networking capabilities.

[0033] For the first method, specifically, the DDS intermediate forwarding software communicates with the simulator and the DDS network through a socket (SOCKET). The DDS intermediate forwarding software is responsible for converting the data sent by the SOCKET into DDS communication data, or receiving the DDS network data and converting it into SOCKET data. The original simulator simulation network platform does not need to integrate and develop the DDS communication module, but such a conversion increases the time delay and bandwidth consumption of network communication, reduces the real-time nature of communication, and loses the natural technical advantages of distributed networking technology. The existence of the DDS intermediate forwarding software also increases the system maintenance cost.

[0034] For the second method, specifically, the original simulator platform is upgraded with functional development, and the DDS data communication interface is directly embedded into the simulator platform software. The whole process requires re-modification and compilation of the original platform software code, which requires a lot of manpower and time.

[0035] In summary, the current DDS-based simulator networking method has shortcomings in terms of efficiency or communication real-time when realizing networking functions.

[0036] In addition, in the current DDS-based simulator networking method, the simulator simulation nodes can act as publishers in the DDS network to send the simulator's own data to the DDS network, or as subscribers to receive other simulator data from the DDS network. It should be noted that the data processed by the simulator can be divided into two categories: state data and interaction data. Among them, state data involves the self-descriptive information of a single simulator, such as position, attitude, and airborne system status, but has no direct impact on other simulators, and generally changes in real time; interaction data directly affects the behavior of other simulators, such as collisions between simulators or weapon hits, which are triggered by specific circumstances.

[0037] The updates of the state data and interaction data involved in the above two methods are all realized through fixed-frequency calls. Due to the existence of the time difference in the call cycle, the simulation status of the interaction data between different simulators may be out of sync, which will have a negative impact on the effect of multi-machine formation or collaborative training, and even directly interrupt the training.

[0038] In order to solve the above technical problems, the embodiments of this statement provide a simulator networking method based on data distribution service. There is no need to add DDS middleware forwarding software, nor is there any need to upgrade and compile the simulation platform code as a whole. Only by generating the simulator interface program and the simulator interface program according to the interface definition language file, the simulator interface data and the data distribution network data can be mapped to realize simulator networking, shortening the development process when realizing the networking function, reducing time delay and bandwidth consumption, and thereby improving the efficiency and real-time communication when realizing the networking function.

[0039] In addition, the DDS networking of the original simulator is upgraded through modular mounting. The data distribution service unit (DDSUnit) is mounted in the simulator simulation network. There is no need to upgrade and compile the simulation platform code as a whole. The DDS network data is directly mapped with the individual simulation network data of the simulator (such as simulator interface data). There is no need to communicate through SOCKET, which avoids the time consumption and bandwidth occupation of SOCKET communication and reduces the maintenance cost of the intermediate forwarding software.

[0040] Furthermore, DDS network data is divided into state data and interaction data according to functional characteristics, and different processing schemes are adopted. Among them, state data is mapped by fixed-frequency calling to ensure that the simulator can write and update individual published data and read and update network subscription data in each simulation cycle; interaction data is mapped by interrupt triggering. When DDS network data is received, the interrupt handler is directly triggered without calling and waiting, avoiding the simulation state difference caused by the calling time difference.

[0041] In order to better understand the embodiments of the present invention, the scenario of the simulator networking method based on the data distribution service is described in detail.

[0042] Figure 1 is a schematic diagram of a scenario of a simulator networking method based on data distribution service provided by the present invention, such as Figure 1 As shown, the scenario of the simulator networking method based on data distribution service includes at least one simulator, a data distribution service unit and a DDS network.

[0043] Among them, at least one simulator may include: Simulator1, Simulator2, Simulator3, Simulator4, ..., SimulatorN, etc., where N is the total number of simulators linked to the DDS network, and N is a positive integer, which is not limited in this embodiment.

[0044] For the i-th simulator Simulatori among N simulators, the simulator may include: a data distribution service unit (DDS Unit), and may also include: peripheral simulation modules such as a motion system (Motion), an instructor console system (Instructor Operating Station, IOS), a sound system (Sound), a visual system (Visual) and a cockpit system (Cockpit).

[0045] Among them, the motion system responds to the posture changes of the simulated subject by obtaining the 6-degree-of-freedom (DOF) data output by the main simulation system; the instructor console system can inject settings such as weather, repositioning, malfunction, subject, etc. into the simulation system of the main simulation system, and can also accept the aircraft parameters (Parameter) of the main simulation system for display; the sound system is used to play environmental sounds (Environment) and audio sounds (Audio) to simulate various sounds heard in the cockpit; the visual system is used to present the external picture of the cockpit observed by the eye point in the cockpit, including the scene that changes with the position / posture of the main perspective eye point (Eye), the weather environment (Weather), the entity target (Entity), etc., and the visual system can return the height above the ground (HAT) and terrain height information (HOT) to the main simulation system. The cockpit equipment system (Cockpit) is installed with real or simulated parts that are consistent with the real aircraft equipment. It provides cockpit operation signal input to the main simulation system through the cockpit interface system (CockpitIO). The indicator lights and other components in the cockpit obtain the signal output of the main simulation system through the cockpit interface system, presenting an indication status consistent with the real aircraft.

[0046] In addition, the main simulation system of the simulator also includes other functional simulation units of the simulator, such as flight, airborne, avionics, fire control and environment. Data communication is carried out between the simulation units through the simulator simulation network.

[0047] Specifically, in the scenario of the simulator networking method based on data distribution service, the basic principles for realizing modular networking of the simulator include: networking principle and modularization principle.

[0048] Networking principle: The simulator data of the simulator emulation network is published to the DDS network through DDSUnit, and other simulator data is subscribed from the DDS network and published to the simulator emulation network.

[0049] Modular principle: A complete flight simulator simulation system includes a simulator simulation network. The simulator simulation network supports mounting different simulation function modules. DDSUnit can be modularly mounted to the corresponding simulator simulation network. Specifically, in order to achieve high efficiency when developing simulator networking functions, the original functional parts are not modified. Instead, a networking module, namely DDSUnit, is added to the original simulator simulation network. Among them, DDSUnit is used to realize the interaction between DDS network data and simulator simulation network data, and can be compiled into a dll file or so file for the simulator simulation platform to call; DDSUnit is also used to subscribe to obtain data from other functional simulation units of the simulator, and publish the data of the simulator to the shared area for use by other functional simulation units of the simulator.

[0050] Figure 2 It is a structural diagram of the simulator networking system provided by the present invention, such as Figure 2 As shown, the simulator networking system may include: a data distribution service unit (DDSUnit), a data distribution service subscription class family (DDS Subscriber), a data distribution service publishing class family (DDS Publisher), a data distribution service manager (DDS Manager), a data distribution service module unit (DDSModulUnit), a compilation file module (Makefile) and a calling function (DDS Lib).

[0051] Among them, the data distribution service unit is used to determine the publish-subscribe communication template program and the simulator interface program. The publish-subscribe communication template program is generated based on the interface definition language file and the interface definition language template program generation tool. The simulator interface program is generated based on the interface definition language file and the simulator interface definition rules.

[0052] The subscription class family is used to subscribe to the data distribution network data of the data distribution service network; the publishing class family is used to publish the simulator interface data to the data distribution service network.

[0053] The data distribution service manager is used to uniformly manage the class initialization, data update, etc. of the subscription class and the publishing class.

[0054] The module unit of the data distribution service, also known as the simulator simulation network data interface docking module, is used to subscribe to the data of other functional simulation units of the simulator from the simulator simulation network and publish the DDS network data to the simulator simulation network.

[0055] Compile files, compile all programs in DDSUnit and link the basic library files required for DDS communication to generate the final dll library or so library that can be called by the simulator simulation network platform.

[0056] Specifically, the specific principles for implementing modular networking of the simulator through the functional parts in DDSUnit may include: networking principle and modularization principle.

[0057] The networking principle includes: integrating the library files of DDS Lib, which provide interface methods for joining the DDS network and reading / writing data. Only by integrating these library files into the networking function module can the DDS network be accessed through the functional interfaces provided in the library files; integrating DDS Publisher, which contains one or more DDS publishing classes generated by interface definition language files. Each DDS publishing class can use the DDS initialization function interface provided by DDS Lib to implement the network access function of the publishing class, and use the DDS network data writing interface to write the data of other functional simulation units of the simulator obtained by DDSModulUnit into the DDS network; integrating DDS Subscriber, which contains one or more DDS subscription classes generated by interface definition language files. Each DDS subscription class can use the DDS initialization function interface provided by DDS Lib to implement the network access function of the subscription class, and use the DDS network data reading interface to write the data received in the DDS network into the interface data defined in DDSModulUnit; due to the DDS Subscriber and DDS Publisher may contain multiple networking class interfaces, and multiple class interfaces contain common behaviors such as initialization. In order to uniformly call the common behaviors of DDS Subscriber and DDS Publisher, each family is instantiated in the DDS Manager function part, and then the instantiated objects (i.e. class objects) of each family are added to the corresponding publishing class container or subscription class container. Finally, the container is traversed to achieve unified call control of initialization and other behaviors.

[0058] The modularization principle includes: integrating the DDSModulUnit class. The DDSModuleUnit class is a class developed according to the calling rules of the simulator simulation platform. After being compiled into the DDSModuleUnit.dll or DDSModuleUnit.so file, it can be integrated and called by the simulation platform. DDSModulUnit establishes a publish / subscribe data cross-linking relationship with other functional modules in the simulator simulation system in the startup phase according to the simulation platform calling module development rules. In the running phase, it can receive the calculation output of other simulation modules according to the simulation scheduling frequency and transmit it to the DDS Publisher, and then write the data to the DDS network through the DDS Publisher. It can also send the obtained DDS network data to other functional modules in the simulator simulation network; the Makefile file can compile DDSUnit into DDSModuleUnit.dll or DDSModuleUnit.so files for the simulator simulation platform to mount. Because DDSUnit is developed according to the calling rules of the simulator simulation platform, DDSUnit supports the data interaction function with other functional modules provided by the simulator simulation platform. The simulator simulation platform loads the DDSModuleUnit.dll or DDSModuleUnit.so callable file at startup, instantiates the DDSModulUnit functional module, and establishes a publish / subscribe data cross-linking relationship with the instantiated objects of other functional modules. Then, during the running phase, the cross-linking data between different functional modules is uniformly updated according to the simulation call frequency. In addition, the Makefile links the basic library files required for DDS communication, so DDSUnit supports the function of interacting with the DDS network. DDSUnit realizes two-way data interaction between the simulator simulation network and the DDS data network.

[0059] It should be noted that the execution subject involved in the embodiment of the present invention can be a simulator networking device based on data distribution services, or it can be an electronic device. Optionally, the electronic device can include: a computer, a mobile terminal, etc.

[0060] The embodiment of the present invention is further described below by taking an electronic device as an example.

[0061] Figure 3 is a flow chart of a simulator networking method based on data distribution service provided by the present invention, such as Figure 3 As shown, the method includes the following steps 301 to 304.

[0062] Step 301: Determine all interface data required for the simulator to connect to the Internet according to the interface definition language determination rules, and obtain an interface definition language file.

[0063] The interface definition language determination rules are rules for defining interface data required for simulator networking, and usually depend on the specific interface definition language specification or programming language standard used.

[0064] An interface definition language file is an abstract language file used to define software component interfaces and is not dependent on any specific programming language.

[0065] Specifically, according to the interface definition language determination rules, all interface data required for the simulator to connect to the Internet are determined, and the interface definition language file is compiled. Throughout the process, the interface definition language file can be used to define the specifications of data types, interfaces, methods, and other software components, which can then be converted into codes in multiple programming languages, thereby achieving cross-language communication and integration.

[0066] Step 302: Generate a publish-subscribe communication template program of a data distribution service in a data distribution service unit according to the interface definition language file and in combination with an interface definition language template program generation tool.

[0067] Among them, the data distribution service unit is used to determine the publish-subscribe communication template program and the simulator interface program. The publish-subscribe communication template program is generated based on the interface definition language file and the interface definition language template program generation tool. The simulator interface program is generated based on the interface definition language file and the simulator interface definition rules.

[0068] The interface definition language template program generation tool is a tool for generating template programs, which is not limited in this embodiment.

[0069] Specifically, after obtaining the interface definition language file, combined with the interface definition language template program generation tool, in the data distribution service unit, a publish-subscribe communication template program is generated based on the interface definition language file and the interface definition language template program generation tool, thereby reducing the repetitive work of developers and significantly improving development efficiency.

[0070] Step 303: Generate a simulator interface program in the data distribution service unit according to the interface definition language file and in combination with the simulator interface definition rules.

[0071] The simulator interface program is used to subscribe to the data of other parts of the simulator in the simulator individual simulation network, and publish the DDS network data to the simulator individual simulation network.

[0072] Specifically, based on the simulator interface definition rules, in the data distribution service unit, a simulator interface program is generated according to the interface definition language file, thereby reducing the repetitive work of developers and significantly improving development efficiency.

[0073] Step 304: Map the simulator interface data and the data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0074] The publish-subscribe communication template program includes: a subscription family publish-subscribe communication template program and a publishing family publish-subscribe communication template program.

[0075] According to the publish-subscribe communication template program and the simulator interface program, the simulator interface data and the data distribution network data are mapped to obtain the mapping result. The whole process does not require the overall upgrade and compilation of the simulation platform code, making development faster and more efficient.

[0076] In some embodiments, the mapping result includes: a mapping relationship between the simulator and the data distribution service network, and a publish-subscribe relationship between the data distribution service unit and other functional simulation units of the simulator.

[0077] Among them, other functional simulation function parts of the simulator may be peripheral simulation systems such as a motion system, an instructor console system, a sound system, a visual system, and a cockpit system, and this embodiment does not limit this.

[0078] In some embodiments, according to the publish-subscribe communication template program and the simulator interface program, the specific implementation method of mapping the simulator interface data and the data distribution network data includes the following: according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, reading the data distribution network data in the subscription class family, and writing the data distribution network data to the first pointer position in the simulator interface program; according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, reading the simulator interface data from the second pointer position in the simulator interface program, and writing the simulator interface data to the data distribution service network.

[0079] The first pointer position is a position for storing written data distribution network data, and the second pointer position is a position for storing simulator interface data.

[0080] Specifically, after determining the publish-subscribe communication template program and the simulator interface program, read the data distribution network data in the subscription class family according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, and write the data distribution network data to the first pointer position in the simulator interface program; at the same time, read the simulator interface data from the second pointer position in the simulator interface program according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, and write the simulator interface data to the data distribution service network. In the whole process, the data distribution network data can be accurately found through the first pointer position, and the simulator interface data can be accurately read through the second pointer position, thereby improving the data writing efficiency.

[0081] In some embodiments, it also includes: in the data distribution service manager, instantiating the subscription class family as a first class object and instantiating the publishing class family as a second class object; passing the first pointer position corresponding to the simulator interface data to the first class object, and passing the second pointer position corresponding to the simulator interface data to the second class object; initializing the network status of the first class object and the second class object; when the initialization is completed and the network connection is established, updating the simulator interface data in the publishing class family.

[0082] The first type of object is a subscription interface instantiated based on the subscription class family, and the second type of object is a publishing interface instantiated based on the publishing class family.

[0083] Specifically, in order to realize the mapping of simulator interface data and data distribution network data, in the data distribution service manager, it is necessary to instantiate the subscription class family as the first class object and instantiate the publishing class family as the second class object; pass the first pointer position corresponding to the simulator interface data to the first class object, and pass the second pointer position corresponding to the simulator interface data to the second class object; initialize the network status of the first class object and the second class object; after the initialization is completed and the network connection is established, update the simulator interface data in the publishing class family. The whole process does not require communication through middleware, and does not need to update the simulator interface data in the publishing class family, making development faster and more efficient.

[0084] Conventionally, data distribution network data is updated in a fixed frequency manner. The embodiments of the present invention involve processing state data and interaction data in different manners.

[0085] Among them, for status data, a fixed-frequency call method is used to update data. When the DDS Subscriber receives DDS network data of status data, it does not directly write the status data into the simulator simulation network, but waits for the next call of the simulator simulation program to update the received status data to the simulator simulation network.

[0086] In some embodiments, it also includes: when the data distribution network data is status data, a fixed-frequency calling method is used to update the status data; when the data distribution network data is interactive data, an interrupt processing method is used to perform interrupt processing and solve the interactive data to obtain a solution result; and simulation is performed based on the solution result.

[0087] Among them, the fixed-frequency calling method is for reading and writing the published and subscribed data for the status data. The interrupt processing method is not to wait for the simulator program to call the periodic call for the interactive data, but to directly send the interrupt information to the simulator in the form of an interrupt. For the system that needs to process the interactive data, the interrupt processing mechanism is triggered, and the next step of processing and solving is directly performed according to the interrupt information.

[0088] Specifically, determine whether the data distribution network data is status data or interactive data. When the data distribution network data is status data, use a fixed-frequency call method to update the status data; when the data distribution network data is interactive data, use an interrupt processing method to perform interrupt processing and solve the interactive data to obtain the solution result; and perform simulation based on the solution result. The entire process uses fixed-frequency calls to update data to avoid the stability problem of the simulation platform caused by a large number of interrupt trigger processing, making the simulation system more stable and controllable. The interactive data is mapped through interrupt triggering. When the DDS network data is received, the interrupt handler is directly triggered without calling and waiting. It has higher real-time performance and avoids the simulation state difference caused by the call time difference.

[0089] In some embodiments, an interrupt processing method is adopted to perform interrupt processing and solving on the interaction data, and the specific implementation method for obtaining the solution result includes the following: determining an interrupt request based on the relevant information of the interaction data; when the interrupt request matches the interrupt registration information, assigning the interaction data to the interrupt data, and generating a target interrupt request carrying the interrupt data, and the interrupt registration information is pre-registered in the interrupt trigger source system; according to the target interrupt request, triggering the corresponding interrupt registration information processing function, solving the interrupt data, and obtaining the solution result.

[0090] The interrupt registration information includes the interrupt trigger source system name, interrupt type, interrupt name, and interrupt processing function, etc. The relevant information of the interactive data may be, for example, the type and meaning of the DDS data, etc., which is not limited in this embodiment.

[0091] Specifically, the interrupt registration information such as the interrupt trigger source system name, interrupt type, interrupt name and interrupt processing function are agreed upon, and the interrupt information is registered to the simulator simulation network when the simulator program is started, so that the simulator program waits for the trigger information when it is running. When the subscription class family receives the subscribed interactive data, the interrupt request is first defined according to the type and meaning of the DDS data, including the interrupt trigger source system name, interrupt data, interrupt data type, interrupt name, etc., where the interrupt trigger source system name, interrupt type, and interrupt name information must be consistent with the information for processing interrupt registration. Then the data received by the subscription class family is assigned to the interrupt data, and finally the interrupt request is sent. After the interrupt request is sent, the interrupt processing function consistent with the interrupt registration information will be entered. To further ensure the correctness of the interrupt data, after entering the interrupt function, the corresponding interrupt registration information processing function is triggered according to the target interrupt request. First, the interrupt data quantity verification and type verification operations are required. After determining that the received interrupt data quantity and type are consistent with the target interrupt data quantity and type, the value of the interrupt data is taken out, and further logical processing is performed according to the value of the interrupt data.

[0092] The advantage of this setting is that the state data is mapped by fixed-frequency calling, ensuring that the simulator can write and update individual published data and read and update network subscription data in each simulation cycle. Interactive data is mapped by interrupt triggering. When DDS network data is received, the interrupt handler is directly triggered without calling and waiting, avoiding the simulation state difference caused by the call time difference.

[0093] The present invention provides a simulator networking method based on data distribution service, which determines all interface data required for simulator networking according to interface definition language determination rules, and obtains interface definition language files; generates a publish-subscribe communication template program of data distribution service in a data distribution service unit in combination with interface definition language template program generation tool according to interface definition language files; generates a simulator interface program in a data distribution service unit in combination with simulator interface definition rules according to interface definition language files; maps simulator interface data and data distribution network data according to publish-subscribe communication template program and simulator interface program. Based on the above embodiments, the technical scheme of the present invention is used to solve the defects of the existing simulator networking method based on DDS in terms of efficiency and communication real-time performance when realizing networking functions, and realizes that there is no need to add DDS middleware forwarding software, and there is no need to upgrade and compile the simulation platform code as a whole. Only by generating simulator interface program and simulator interface program according to interface definition language files, the simulator interface data and data distribution network data can be mapped to realize simulator networking, shortening the development process when realizing networking functions, and reducing time delay and bandwidth consumption, thereby improving efficiency and communication real-time performance when realizing networking functions.

[0094] Figure 4 is a structural diagram of a simulator networking system based on data distribution services provided by the present invention, such as Figure 4 As shown, the simulator networking system 400 based on the data distribution service includes a subscription class 401 of the data distribution service, a publishing class 402, a data distribution service unit 403 and a data distribution service manager 404.

[0095] Among them, the subscription class family is used to subscribe to the data distribution network data of the data distribution service network 10; the publishing class family is used to publish the simulator interface data to the data distribution service network; the data distribution service unit is used to determine the publish-subscribe communication template program and the simulator interface program, the publish-subscribe communication template program is generated based on the interface definition language file and the interface definition language template program generation tool, and the simulator interface program is generated based on the interface definition language file and the simulator interface definition rule; the data distribution service manager is used to instantiate the subscription class family as a first-class object and instantiate the publishing class family as a second-class object; pass the first pointer position corresponding to the simulator interface data to the first-class object, and pass the second pointer position corresponding to the simulator interface data to the second-class object; initialize the network status of the first-class object and the second-class object; when the initialization is completed and the network connection is established, update the simulator interface data in the publishing class family. Among them, the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program are determined based on the interface definition language file and the interface definition language template program, and the interface definition language file is determined based on the interface definition language determination rule.

[0096] Among them, the simulator networking system based on data distribution service also includes DDS Lib calling function, which is the library file for DDS distributed network communication and the basis for implementing DDS networking function calling. The simulator networking system based on data distribution service also includes Makefile compilation file, which is used to compile all programs in the data distribution service unit and link the basic library files required for DDS communication to generate the final dll or so library that can be called by the simulator simulation network platform.

[0097] Specifically, the library file provides an interface method for joining the DDS network and reading / writing data. Only by integrating these library files into the simulator networking system based on the data distribution service can the DDS network be accessed through the functional interface provided in the library file. The publishing class family contains one or more DDS publishing classes generated by interface definition language files. Each DDS publishing class can use the DDS initialization function interface provided by DDS Lib to implement the network access function of the publishing class, and use the DDS network data writing interface to write the data of other simulation function modules of the simulator obtained by the data distribution service unit into the DDS network. The subscription class family contains one or more DDS subscription classes generated by interface definition language files. Each DDS subscription class can use the DDS initialization function interface provided by DDS Lib to implement the network access function of the subscription class, and use the DDS network data reading interface to write the data received in the DDS network into the interface data defined in the data distribution service unit.

[0098] Furthermore, since the publishing class family and the subscription class family may contain multiple networking class interfaces, and multiple class interfaces contain common behaviors such as initialization, in order to uniformly call the common behaviors of the publishing class family and the subscription class family, the class is instantiated in the data distribution service manager part, and then the instantiated object of the class is added to the publishing class container or the subscription class container, and finally the container is traversed to achieve unified call control of initialization and other behaviors.

[0099] Specifically, a data distribution service unit is integrated into the simulator networking system based on the data distribution service. The data distribution service unit is a class developed according to the calling rules of the simulator simulation platform. After being compiled into a .dll or .so file, it can be integrated and called by the simulation platform. The data distribution service unit establishes a publish / subscribe data cross-linking relationship with other functional modules in the simulator simulation system in the startup phase according to the simulation platform calling module development rules. In the running phase, it can receive the calculation output of other simulation modules according to the simulation scheduling frequency and transmit it to the publishing class family, and then write the data to the DDS network through the publishing class family. The acquired DDS network data can also be sent to other functional modules in the simulator simulation network. The Makefile file can compile the DDS data distribution service unit into a .dll or .so file for mounting on the simulator simulation platform. Because the data distribution service unit is developed according to the calling rules of the simulator simulation platform, the data distribution service unit supports the data interaction function with other functional modules provided by the simulator simulation platform. The simulator simulation platform loads the .dll or .so callable file at startup, instantiates the data distribution service manager, and establishes a publish / subscribe data cross-linking relationship with the instantiated objects of other functional modules, and then uniformly updates the cross-linking data between different functional modules according to the simulation call frequency during the running phase. And the Makefile links the basic library files required for DDS communication, so the data distribution service unit supports the function of interacting with the DDS network. The data distribution service unit realizes the two-way data interaction between the simulator simulation network and the DDS data network.

[0100] The present invention provides a simulator networking system based on data distribution service, including a subscription class family, a publishing class family, a data distribution service unit and a data distribution service manager. The subscription class family is used to subscribe to the data distribution network data of the data distribution service network 10; the publishing class family is used to publish the simulator interface data to the data distribution service network; the data distribution service unit is used to determine the publishing and subscription communication template program and the simulator interface program, the publishing and subscription communication template program is generated based on the interface definition language file and the interface definition language template program generation tool, and the simulator interface program is generated based on the interface definition language file and the simulator interface definition rule; the data distribution service manager is used to instantiate the subscription class family as a first class object and instantiate the publishing class family as a second class object; pass the first pointer position corresponding to the simulator interface data to the first class object, and pass the second pointer position corresponding to the simulator interface data to the second class object; initialize the network status of the first class object and the second class object; when the initialization is completed and the network connection is established, update the simulator interface data in the publishing class family. Among them, the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program are determined based on the interface definition language file and the interface definition language template program, and the interface definition language file is determined based on the interface definition language determination rule. On the basis of the above embodiments, the technical solution of the present invention is used to solve the defects of the current DDS-based simulator networking method in terms of efficiency and communication real-time performance when realizing the networking function, and there is no need to add DDS middleware forwarding software, nor to upgrade and compile the simulation platform code as a whole. Only by generating the simulator interface program and the simulator interface program according to the interface definition language file, the simulator interface data and the data distribution network data can be mapped to realize the simulator networking, shortening the development process when realizing the networking function, and reducing time delays and bandwidth consumption, thereby improving the efficiency and communication real-time performance when realizing the networking function.

[0101] The following is a description of the simulator networking device based on data distribution service provided by the present invention. The simulator networking device based on data distribution service described below and the simulator networking method based on data distribution service described above can be referenced to each other.

[0102] Figure 5 is a structural diagram of a simulator networking device based on data distribution service provided by the present invention, such as Figure 5 As shown, the simulator networking device 500 based on data distribution service includes the following: a file determination module 501 , a template program determination module 502 , an interface program determination module 503 and a data mapping module 504 .

[0103] The file determination module 501 is used to determine all interface data required for the simulator to connect to the network according to the interface definition language determination rules, and obtain an interface definition language file.

[0104] The template program determination module 502 is used to generate a publish-subscribe communication template program of the data distribution service in the data distribution service unit according to the interface definition language file and in combination with the interface definition language template program generation tool.

[0105] The interface program determination module 503 is used to generate a simulator interface program in the data distribution service unit according to the interface definition language file and in combination with the simulator interface definition rules.

[0106] The data mapping module 504 is used to map the simulator interface data and the data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0107] Optionally, the publish-subscribe communication template program includes: a subscription class family publish-subscribe communication template program and a publishing class family publish-subscribe communication template program.

[0108] Optionally, the data mapping module 504 is specifically used to: read the data distribution network data in the subscription class family according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, and write the data distribution network data to the first pointer position in the simulator interface program; read the simulator interface data from the second pointer position in the simulator interface program according to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, and write the simulator interface data to the data distribution service network.

[0109] Optionally, the device further includes: a data update module. The data update module is used to: in the data distribution service manager, instantiate the subscription class family as the first class object and instantiate the publishing class family as the second class object; pass the first pointer position corresponding to the simulator interface data to the first class object, and pass the second pointer position corresponding to the simulator interface data to the second class object; initialize the network status of the first class object and the second class object; and update the simulator interface data in the publishing class family when the initialization is completed and the network connection is established.

[0110] Optionally, the mapping result includes: a mapping relationship between the simulator and the data distribution service network, and a publish-subscribe relationship between the data distribution service unit and other functional simulation units of the simulator.

[0111] Optionally, the device further includes: a simulation module. The simulation module is used to: when the data distribution network data is state data, use a fixed frequency call method to update the state data; when the data distribution network data is interactive data, use an interrupt processing method to perform interrupt processing and solve the interactive data to obtain a solution result; and perform simulation according to the solution result.

[0112] Optionally, the simulation module adopts an interrupt processing method to perform interrupt processing and solve the interaction data to obtain a solution result, which is specifically used for: determining an interrupt request based on relevant information of the interaction data; when the interrupt request matches the interrupt registration information, assigning the interaction data as interrupt data, and generating a target interrupt request carrying the interrupt data, and the interrupt registration information is pre-registered in the interrupt trigger source system; according to the target interrupt request, triggering the corresponding interrupt registration information processing function, solving the interrupt data, and obtaining a solution result.

[0113] Figure 6 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 complete mutual communication through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute a simulator networking method based on a data distribution service, the method comprising: determining all interface data required for simulator networking according to an interface definition language determination rule, and obtaining an interface definition language file; generating a publish-subscribe communication template program of a data distribution service in a data distribution service unit according to the interface definition language file and in combination with an interface definition language template program generation tool; generating a simulator interface program in a data distribution service unit according to the interface definition language file and in combination with a simulator interface definition rule; and mapping simulator interface data and data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0114] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0115] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the simulator networking method based on the data distribution service provided by the above methods, and the method includes: determining rules according to an interface definition language, determining all interface data required for simulator networking, and obtaining an interface definition language file; generating a publish-subscribe communication template program for a data distribution service in a data distribution service unit according to the interface definition language file and in combination with an interface definition language template program generation tool; generating a simulator interface program in a data distribution service unit according to the interface definition language file and in combination with the simulator interface definition rules; and mapping simulator interface data and data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0116] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the simulator networking method based on the data distribution service provided by the above-mentioned methods, the method comprising: determining rules according to an interface definition language, determining all interface data required for simulator networking, and obtaining an interface definition language file; generating a publish-subscribe communication template program for a data distribution service in a data distribution service unit according to the interface definition language file and in combination with an interface definition language template program generation tool; generating a simulator interface program in a data distribution service unit according to the interface definition language file and in combination with simulator interface definition rules; and mapping simulator interface data and data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

[0117] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0118] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A simulator networking method based on data distribution service, characterized in that: include: According to the interface definition language determination rules, all interface data required for the simulator to be connected to the network are determined, and an interface definition language file is obtained; Generate a publish-subscribe communication template program of a data distribution service in a data distribution service unit according to the interface definition language file and in combination with an interface definition language template program generation tool; Generating a simulator interface program in the data distribution service unit according to the interface definition language file and in combination with the simulator interface definition rules; According to the publish-subscribe communication template program and the simulator interface program, the simulator interface data and the data distribution network data are mapped.

2. The simulator networking method based on data distribution service according to claim 1, characterized in that: The publish-subscribe communication template program includes: a subscription family publish-subscribe communication template program and a publishing family publish-subscribe communication template program; the mapping of simulator interface data and data distribution network data according to the publish-subscribe communication template program and the simulator interface program includes: According to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, read the data distribution network data in the subscription class family, and write the data distribution network data to the first pointer position in the simulator interface program; According to the subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program, the simulator interface data is read from the second pointer position in the simulator interface program, and the simulator interface data is written into the data distribution service network.

3. The simulator networking method based on data distribution service according to claim 2, characterized in that: The method further comprises: In the data distribution service manager, the subscription class family is instantiated as the first class object and the publishing class family is instantiated as the second class object; the first pointer position corresponding to the simulator interface data is passed to the first class object, and the second pointer position corresponding to the simulator interface data is passed to the second class object; the network status of the first class object and the second class object is initialized; when the initialization is completed and the network connection is established, the simulator interface data in the publishing class family is updated.

4. The simulator networking method based on data distribution service according to any one of claims 1 to 3, characterized in that: The mapping result includes: a mapping relationship between the simulator and the data distribution service network, and a publish-subscribe relationship between the data distribution service unit and other functional simulation units of the simulator.

5. The simulator networking method based on data distribution service according to any one of claims 1 to 3, characterized in that: The method further comprises: In the case where the data distribution network data is status data, a fixed frequency calling method is adopted to update the status data; In the case where the data distribution network data is interactive data, an interrupt processing method is adopted to perform interrupt processing and solving on the interactive data to obtain a solving result; and simulation is performed according to the solving result.

6. The simulator networking method based on data distribution service according to claim 5, characterized in that: The method of using an interrupt processing method to perform interrupt processing and solving on the interaction data to obtain a solving result includes: Determining an interrupt request according to relevant information of the interaction data; In the case where the interrupt request matches the interrupt registration information, assigning the interaction data as interrupt data and generating a target interrupt request carrying the interrupt data, wherein the interrupt registration information is pre-registered in the interrupt trigger source system; According to the target interrupt request, a corresponding interrupt registration information processing function is triggered, the interrupt data is solved, and the solution result is obtained.

7. A simulator networking system based on data distribution service, characterized in that: include: The subscription class, publishing class, data distribution service unit and data distribution service manager of the data distribution service; wherein, The subscription class family is used to subscribe to data distribution network data of the data distribution service network; The publishing class family is used to publish simulator interface data to the data distribution service network; The data distribution service unit is used to determine a publish-subscribe communication template program and a simulator interface program, wherein the publish-subscribe communication template program is generated based on an interface definition language file and an interface definition language template program generation tool, and the simulator interface program is generated based on the interface definition language file and a simulator interface definition rule; The data distribution service manager is used to instantiate the subscription class family as a first-class object and instantiate the publishing class family as a second-class object; pass the first pointer position corresponding to the simulator interface data to the first-class object, and pass the second pointer position corresponding to the simulator interface data to the second-class object; initialize the network status of the first-class object and the second-class object; and when the initialization is completed and the network connection is established, update the simulator interface data in the publishing class family. The subscription class family publish-subscribe communication template program and the publishing class family publish-subscribe communication template program are determined based on an interface definition language file and an interface definition language template program, and the interface definition language file is determined based on an interface definition language determination rule.

8. A simulator networking device based on data distribution service, characterized in that: include: A file determination module, used to determine all interface data required for the simulator to connect to the network according to the interface definition language determination rules, and obtain an interface definition language file; A template program determination module, used to generate a publish-subscribe communication template program of a data distribution service in a data distribution service unit according to the interface definition language file in combination with an interface definition language template program generation tool; An interface program determination module, used to generate a simulator interface program in the data distribution service unit according to the interface definition language file and in combination with simulator interface definition rules; The data mapping module is used to map the simulator interface data and the data distribution network data according to the publish-subscribe communication template program and the simulator interface program.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the simulator networking method based on data distribution service as claimed in any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the simulator networking method based on data distribution service as claimed in any one of claims 1 to 6 is implemented.

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