Modular AUV system based on CAN bus elastic networking

Abstract

The invention discloses a modular AUV (Autonomous Underwater Vehicle) system based on CAN (Controller Area Network) bus elastic networking, and belongs to the technical field of AUV modularization. The invention aims to solve the problem that the single communication channel design of the existing modular AUV has a communication bottleneck and affects the communication efficiency. Comprising a bow section module, a front auxiliary propulsion section module, a load section module, a core control section module, a navigation section module, a rear auxiliary propulsion section module and a stern section module in sequence from the bow to the stern, each module is provided with a load carrying interface, and connection of carrying equipment is controlled through corresponding control nodes; the data of the carrying equipment is transmitted through a three-way CAN bus and a network cable, and is communicated with the main control module; adjacent modules of the AUV system are correspondingly connected through modular interfaces. According to the invention, a wider communication channel and redundant space are provided for the AUV, and the reliability and stability of communication are enhanced.

Description

Technical Field

[0001] The present invention relates to a modular AUV system based on CAN bus elastic networking, belonging to the technical field of AUV modularization. Background Art

[0002] Modular design, a key trend in the development of autonomous underwater vehicles (AUVs), has greatly enhanced their flexibility and scalability. However, as modular AUV systems become increasingly complex, challenges in communication efficiency, payload distribution, and system self-diagnosis capabilities are becoming increasingly prominent, becoming key factors hindering further improvement in modular AUV performance.

[0003] In terms of communication, modular AUVs typically consist of multiple modules with distinct functions, which require a communication bus for data transmission and command control. However, traditional single-channel designs often lead to communication bottlenecks, especially in complex underwater environments. Inefficient information transmission is a significant constraint on the performance of modular AUVs. Although CAN (Controller Area Network) bus technology is widely used in modular AUV communication design due to its high communication speed, reliability, and flexible connectivity, designing an efficient and stable CAN bus architecture to support multi-module and multi-mission communication in complex environments remains an urgent challenge. Payload distribution is particularly complex for modular AUVs. Due to the varying physical size, power consumption, and mission requirements of each module, traditional static load distribution methods often fail to meet the flexibility and efficiency requirements of modular AUVs during dynamic mission execution. In complex underwater environments, designing an intelligent load distribution solution that dynamically adjusts the installation position and operating status of each module based on mission requirements, equipment power consumption, and physical layout to maximize the AUV's cargo space and energy utilization is key to improving payload flexibility and mission efficiency in modular AUVs.

[0004] Furthermore, the modular AUV's system self-checking capabilities are a significant factor limiting its performance. Due to the modular AUV's complexity and numerous components, and its susceptibility to environmental complexity and equipment aging during underwater operations, various faults are prone to occur. Traditional fault detection methods typically rely on manual inspections or scheduled maintenance, which are not only inefficient but also difficult to detect potential faults in a timely manner. Therefore, designing an efficient self-checking solution that can regularly self-check the modular AUV's bus status, device connectivity, and functional integrity, and promptly detect and report potential faults, has become a key means of improving the efficiency and safety of modular AUV operations and maintenance.

[0005] In summary, the industry urgently needs an innovative solution to the problems of modular AUVs in communication efficiency, payload distribution, and system self-checking capabilities. Summary of the Invention

[0006] Aiming at the problem that the single communication channel design of existing modular AUVs has a communication bottleneck and affects the communication efficiency, the present invention provides a modular AUV system based on CAN bus elastic networking.

[0007] The present invention provides a modular AUV system based on CAN bus flexible networking. The AUV system includes the following modules from bow to stern:

[0008] The bow section module is equipped with a bow section load carrying interface, controls the connection of the carried equipment through the bow section control node, and transmits the data of the carried equipment through three CAN buses and network cables to communicate with the main control module;

[0009] The front auxiliary propulsion section module is equipped with a front auxiliary propulsion payload loading interface, controls the connection of the loaded equipment through the front auxiliary propulsion section control node, and transmits the data of the loaded equipment through three CAN buses and network cables to communicate with the main control module;

[0010] The payload segment module is equipped with sensor and actuator mounting interfaces, controls the connection of the mounted devices through the payload segment control node, transmits the data of the mounted devices through three CAN buses and network cables, and communicates with the main control module;

[0011] The core control segment module is configured with the main control module, as well as the onboard interfaces of key devices, power management, adaptive adjustment mechanism, GPS and navigation system. It controls the connection of onboard devices through the core control segment control node, and transmits the data of the onboard devices through three CAN buses and network cables to communicate with the main control module.

[0012] The navigation segment module is equipped with a navigation device and an additional lithium battery mounting interface. It controls the connection of the mounted device through the navigation segment control node, transmits the data of the mounted device through three CAN buses and network cables, and communicates with the main control module.

[0013] The rear auxiliary propulsion section module is equipped with a rear auxiliary propulsion payload carrying interface, controls the connection of the carried equipment through the rear auxiliary propulsion section control node, and transmits the data of the carried equipment through three CAN buses and network cables to communicate with the main control module;

[0014] The stern module is equipped with interfaces for the main propulsion and steering gear, controls the connection of the onboard equipment through the stern control node, and transmits the data of the onboard equipment through three CAN buses to communicate with the main control module;

[0015] Adjacent modules of the AUV system are connected via modular interfaces.

[0016] According to the modular AUV system based on CAN bus elastic networking of the present invention, the bow section control node, the front auxiliary propulsion section control node, the payload section control node, the core control section control node, the navigation section control node, the rear auxiliary propulsion section control node and the stern section control node are respectively connected to the three CAN buses through three CAN controllers;

[0017] The bow section control node, front auxiliary propulsion section control node, payload section control node, core control section control node, navigation section control node and rear auxiliary propulsion section control node are connected by network cables through switches in sequence. The switch corresponding to the core control section control node is the main switch; the core control section control node is also equipped with an optical terminal to remotely control and debug each module of the AUV system through optical fiber communication.

[0018] According to the modular AUV system based on CAN bus elastic networking of the present invention, the main control module adopts PC104 as the main control unit, and manages and schedules system functions based on the received data;

[0019] The main control module replaces the equipment and communication paths of each module through each control node according to the task instructions to realize the flexible networking mechanism; the equipment carried by each module includes network protocol equipment and CAN bus protocol equipment;

[0020] The three-way CAN bus forms three independent communication channels between the main control module and each module of the AUV system.

[0021] According to the modular AUV system based on CAN bus elastic networking of the present invention, the main control module allocates a data transmission bus to the onboard equipment to be connected based on the judgment of the load status of the communication network; the communication network is formed by three CAN buses and a network cable; the data transmission bus includes three CAN buses and one network cable;

[0022] The main control module dynamically adjusts the network parameters of the communication network formed by the three-way CAN bus and the network cable, and performs performance evaluation and optimization of the communication network.

[0023] The main control module monitors the load status of each data transmission bus and preferentially assigns the device to be connected to the data transmission bus in the idle state; further, if there is no idle data transmission bus, the device to be connected is preferentially assigned to the data transmission bus in the low-load state; further, if there is no low-load data transmission bus, the current load of each data transmission bus is determined, and the device to be connected is preferentially assigned to the data transmission bus with the lowest load rate;

[0024] Otherwise, the device to be connected will be added to the waiting queue, and the load status of the waiting queue and each data transmission bus will be checked regularly; the data transmission buses will be sorted according to the low-load priority of the load status, and the data transmission bus will be allocated to the current first waiting device to be connected according to the sorting result. The low-load priority of the load status is idle state, low-load state and lowest load rate state in sequence.

[0025] According to the modular AUV system based on CAN bus flexible networking of the present invention, the main control module also performs dynamic resource allocation and scheduling based on the judgment of the load status of the communication network:

[0026] The main control module monitors the load status of each data transmission bus, including the number of real-time data packets and the load change rate;

[0027] For a data transmission bus whose load rate reaches a set threshold, selecting the devices on board to switch the data transmission bus according to the priority order;

[0028] The main control module also conducts real-time evaluation of the data transmission requirements, processing power requirements, and real-time requirements of each onboard device based on the received data; dynamically allocates data transmission bus resources based on the evaluation results, and assigns matching data transmission buses, processing priorities, and storage resources to each onboard device.

[0029] According to the modular AUV system based on CAN bus flexible networking of the present invention, the method for the main control module to perform real-time evaluation of the data transmission requirements, processing capacity requirements, and real-time requirements of each onboard device is as follows:

[0030] The basic information of the mounted devices is read from the configuration file, and the mounted devices are compound-classified based on the data volume and real-time requirements of the mounted devices; the mounted devices are prioritized based on the classification results to obtain a sorted list.

[0031] According to the modular AUV system based on CAN bus elastic networking of the present invention, the main control module designs a bus selection strategy for the corresponding onboard equipment based on the load status monitoring results of each data transmission bus and a sorted list; based on the bus selection strategy, a matching data transmission bus access is dynamically selected for the onboard equipment.

[0032] According to the modular AUV system based on CAN bus elastic networking of the present invention, the main control module is also used to perform status self-check on the three CAN buses:

[0033] The main control module sends a bus self-test command to each control node through the CAN controller; the status of the CAN bus is determined based on the self-test response returned by each control node. A CAN bus with normal communication is considered normal, while a CAN bus with abnormal communication or no response after timeout is considered faulty.

[0034] For the CAN bus in fault state, the main control module performs fault recovery operations:

[0035] Restart the CAN controller corresponding to the CAN bus in the faulty state and reconfigure the bus parameters of the CAN bus in the faulty state; if the CAN bus in the faulty state recovers successfully, it is judged to be in normal state; otherwise, the CAN bus in the faulty state is marked as a permanent fault state and removed from the AUV system or switched to a backup bus;

[0036] When the CAN bus is marked as a permanent fault state, the main control module switches all the devices on the CAN bus in the permanent fault state to the backup bus and updates the communication configuration information of the AUV system; then the state self-check process is performed until all CAN buses are in normal state;

[0037] The main control module records the information of each status self-check in a log file.

[0038] According to the modular AUV system based on CAN bus flexible networking of the present invention, the main control module is also used to perform equipment self-test on all onboard equipment:

[0039] The main control module sends an access request to the CAN controller corresponding to the mounted device through the CAN bus, and determines that the connection is successful based on the response of the CAN controller; after the connection is successful, corresponding functional checks are performed in turn according to the functions of each mounted device; for mounted devices that fail the initial self-test, the device status is repaired by resending instructions, reconfiguring parameters and re-powering on. For mounted devices that fail to be repaired, they are marked as devices to be repaired.

[0040] According to the modular AUV system based on CAN bus elastic networking of the present invention, the network protocol equipment includes a forward-looking sonar, a camera, a laser scanner, a multi-beam bathymetric sonar, a side-scan sonar, a low-frequency synthetic aperture sonar and a CCD;

[0041] The CAN bus protocol equipment includes CTD, thruster, shallow layer profiler, acoustic positioning, strobe light, magnetometer, altimeter, depth gauge, water leakage detection device, load jettisoning mechanism, power management, adaptive attitude adjustment mechanism, GPS, Beidou, digital radio, Iridium, inertial navigation, DVL, additional lithium battery system and steering gear.

[0042] Beneficial effects of the invention: The present invention proposes a modular autonomous underwater vehicle (AUV), which realizes intelligent CAN bus elastic networking and system self-checking between the equipment carried by each module through configuration, solving the problems faced by traditional AUVs in complex underwater operations, such as communication bottlenecks, uneven load distribution and insufficient system self-checking capabilities.

[0043] The present invention provides AUV with a wider communication channel and redundant space by introducing a three-way independent CAN bus architecture, thereby enhancing the reliability and stability of communication. In terms of intelligent elastic networking, the load status of each CAN bus can be monitored in real time based on an intelligent algorithm, and the device access strategy can be intelligently adjusted. When a bus is busy, the device to be connected is allocated to an idle or lightly loaded bus based on the evaluation, thereby achieving dynamic optimization of resource allocation, avoiding communication bottlenecks, and improving communication efficiency. In terms of intelligent load distribution, combined with the modular design of the AUV, the operating status of each module is dynamically adjusted according to various factors such as mission requirements, equipment power consumption, and physical layout, maximizing the use of the AUV's carrying space and energy, breaking through traditional load limitations, and supporting more complex mission execution. In addition, the system of the present invention can also realize CAN bus self-test, can regularly perform self-tests on the bus status, equipment connectivity, and functional integrity, promptly discover and report potential faults, improve the operation and maintenance efficiency and safety of the AUV, reduce the system failure rate, and extend its service life.

[0044] By introducing a three-way CAN bus for intelligent and flexible networking, payload distribution, and comprehensive self-testing, this invention significantly improves the modular AUV's communication efficiency, payload flexibility, and system reliability. This provides new technical insights and solutions for AUV design and application, and promotes the advancement and development of underwater exploration and operation technologies. This invention is not only applicable to modular AUVs but also provides a reference for the design and optimization of other similar underwater robots or unmanned systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic diagram of the network connection of the modular AUV system based on CAN bus elastic networking according to the present invention;

[0046] Figure 2 yes Figure 1 Schematic diagram of the system architecture of the bow section control node, front auxiliary propulsion section control node, payload section control node and core control section control node;

[0047] Figure 3 yes Figure 1 Schematic diagram of the system architecture of the core control segment control node, navigation segment control node, rear auxiliary propulsion segment control node and stern segment control node;

[0048] Figure 4This is a flowchart of the elastic networking mechanism;

[0049] Figure 5 It is a flowchart of network initialization and configuration;

[0050] Figure 6 It is a resource allocation and scheduling flow chart;

[0051] Figure 7 It is a flow chart of the intelligent allocation mechanism;

[0052] Figure 8 It is a flow chart of the dynamic adjustment mechanism;

[0053] Figure 9 It is a self-test flow chart;

[0054] Figure 10 It is a flow chart of the fault bus switching mechanism;

[0055] Figure 11 It is a bus specific switching flow chart;

[0056] Figure 12 This is a schematic diagram of the payload that a modular AUV can carry. DETAILED DESCRIPTION

[0057] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0058] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0059] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0060] Specific implementation method 1. Combination Figures 1 to 3 As shown, the present invention provides a modular AUV system based on CAN bus elastic networking. The AUV system includes the following modules from bow to stern:

[0061] The bow module is equipped with a bow payload loading interface. The bow control node controls the connection of loaded equipment and transmits data from these equipment via three CAN buses and a network cable, communicating with the main control module. The bow control node is responsible for controlling the bow payload system, including the access and management of devices such as the CTD and forward-looking sonar. The CTD uses the RS232 protocol to transmit data via the CAN bus, while other devices transmit data via a network cable.

[0062] The front auxiliary propulsion section module is equipped with a front auxiliary propulsion payload carrying interface, controls the connection of the carried equipment through the front auxiliary propulsion section control node, and transmits the data of the carried equipment through three CAN buses and network cables to communicate with the main control module; the front auxiliary propulsion section control node is equipped with front side thrusters and front vertical thrusters according to motion control needs, and communicates with the main control module through the CAN bus.

[0063] The payload segment module is equipped with interfaces for sensors and actuators. It controls the connection of the onboard equipment through the payload segment control node, transmits the data of the onboard equipment through three CAN buses and network cables, and communicates with the main control module. The payload segment control node is equipped with various sensors and actuators according to mission requirements, such as laser scanners and multi-beam bathymetric sonars, and transmits data through network cables and CAN buses.

[0064] The core control segment module is equipped with the main control module, as well as the interfaces for key equipment, power management, adaptive adjustment mechanism, GPS, and navigation systems. The core control segment control node controls the connection of the onboard equipment and transmits the data of the onboard equipment through three CAN buses and network cables to communicate with the main control module. The core control segment control node is equipped with key equipment such as the depth gauge, water leakage detection device, and load jettisoning device, as well as navigation systems such as power management, adaptive adjustment mechanism, GPS, and Beidou navigation, and communicates with the main control module through the CAN bus.

[0065] The navigation segment module is equipped with interfaces for navigation equipment and additional lithium batteries. It controls the connection of the onboard equipment through the navigation segment control node, transmits the data of the onboard equipment through three CAN buses and network cables, and communicates with the main control module. The navigation segment control node is equipped with navigation equipment such as inertial navigation and DVL (Doppler velocimeter), as well as additional lithium batteries, and transmits data through the CAN bus.

[0066] The rear auxiliary propulsion section module is equipped with a rear auxiliary propulsion payload loading interface. It controls the connection of the loaded equipment through the rear auxiliary propulsion section control node, transmits the data of the loaded equipment through three CAN buses and network cables, and communicates with the main control module. The rear auxiliary propulsion section control node carries the rear side thrusters and rear vertical thrusters according to motion control requirements and communicates with the main control module through the CAN bus.

[0067] The stern module is equipped with interfaces for the main thruster and steering gear. It controls the connection of the onboard equipment through the stern control node and transmits the data of the onboard equipment through three CAN buses to communicate with the main control module. The stern control node is equipped with the main thruster and steering gear, and realizes precise motion control through the CAN bus.

[0068] Adjacent modules of the AUV system are connected via modular interfaces.

[0069] The system of the present invention designs a modular AUV from four aspects: system architecture, elastic networking mechanism, intelligent allocation technology and self-checking technology.

[0070] Furthermore, the bow section control node, the front auxiliary propulsion section control node, the payload section control node, the core control section control node, the navigation section control node, the rear auxiliary propulsion section control node and the stern section control node are respectively connected to the three CAN buses through three CAN controllers;

[0071] The bow section control node, front auxiliary propulsion section control node, payload section control node, core control section control node, navigation section control node and rear auxiliary propulsion section control node are connected by network cables through switches in sequence. The switch corresponding to the core control section control node is the main switch; the core control section control node is also equipped with an optical terminal to remotely control and debug each module of the AUV system through optical fiber communication.

[0072] This implementation utilizes the high bandwidth and low attenuation characteristics of fiber-optic communication to achieve stable remote control and debugging of modular AUVs, significantly improving the convenience of operation and the response speed of the system. In addition, by introducing a network switch, a high-speed information network is built between the payload modules, enabling high-speed data transmission and sharing, further enhancing the system's data processing capabilities, mission execution flexibility, and overall performance.

[0073] Combine Figures 4 to 6 As shown, the main control module uses PC104 as the main control unit, which manages and schedules system functions based on the received data to ensure accurate and efficient task execution;

[0074] The main control module replaces the equipment and communication paths of each module through each control node according to the task instructions to realize the flexible networking mechanism; the equipment carried by each module includes network protocol equipment and CAN bus protocol equipment;

[0075] The three-way CAN bus forms three independent communication channels between the main control module and each module of the AUV system.

[0076] In this embodiment, the AUV system is highly flexible and adaptable, and can replace corresponding functional modules, i.e., payload equipment, according to different mission requirements, thereby completing a variety of underwater missions. The equipment that can be carried can be classified according to the communication transmission method, including but not limited to the following equipment:

[0077] As an example, the network protocol devices include forward-looking sonar, camera, laser scanner, multi-beam bathymetric sonar, side-scan sonar, low-frequency synthetic aperture sonar and CCD devices;

[0078] The CAN bus protocol equipment includes CTD, thruster, shallow subsurface profiler, acoustic positioning, strobe light, magnetometer, altimeter, depth gauge, water leakage detection device, load jettisoning mechanism, power management, adaptive attitude adjustment mechanism, GPS, Beidou, digital radio, Iridium, inertial navigation, DVL, additional lithium battery system and steering gear, etc.

[0079] Depending on the different payload combinations, the following tasks can be completed but are not limited to: marine ecological research, seabed topography mapping, underwater archaeological surveys, marine environmental testing, underwater pipeline inspections, etc.

[0080] The three-way CAN bus serves as the main communication channel of the system communication line, connecting the main control module and various functional modules to form three independent communication channels to ensure the reliability and stability of communication.

[0081] Network cables are used to transmit data that requires high bandwidth, such as video streams, high-resolution images, and data from some sensors.

[0082] Elastic networking mechanism:

[0083] Flexible networking means that modular AUVs can intelligently adjust device access and communication paths based on the current network status and mission requirements, thereby achieving dynamic resource optimization and efficient utilization. The core of this mechanism lies in its ability to intelligently allocate device access and communication resources based on factors such as bus load, device type, data volume, and real-time requirements, thereby avoiding communication congestion and improving communication efficiency and stability.

[0084] The main control module allocates a data transmission bus to the connected device based on the judgment of the load status of the communication network; the communication network is formed by three CAN buses and a network cable; the data transmission bus includes three CAN buses and one network cable;

[0085] The main control module dynamically adjusts the network parameters of the communication network formed by the three-way CAN bus and the network cable, and performs performance evaluation and optimization of the communication network.

[0086] The main control module monitors the load status of each data transmission bus and preferentially assigns the device to be connected to the data transmission bus in the idle state; further, if there is no idle data transmission bus, the device to be connected is preferentially assigned to the data transmission bus in the low-load state; further, if there is no low-load data transmission bus, the current load of each data transmission bus is determined, and the device to be connected is preferentially assigned to the data transmission bus with the lowest load rate;

[0087] Otherwise, the device to be connected will be added to the waiting queue, and the load status of the waiting queue and each data transmission bus will be checked regularly; the data transmission buses will be sorted according to the low-load priority of the load status, and the data transmission bus will be allocated to the current first waiting device to be connected according to the sorting result. The low-load priority of the load status is idle state, low-load state and lowest load rate state in sequence.

[0088] Furthermore, the main control module also performs dynamic resource allocation and scheduling based on the judgment of the communication network load status:

[0089] The main control module monitors the load status of each data transmission bus, including the number of real-time data packets and the load change rate;

[0090] For a data transmission bus whose load rate reaches a set threshold, selecting the devices on board to switch the data transmission bus according to the priority order;

[0091] The main control module also conducts real-time evaluation of the data transmission requirements, processing power requirements, and real-time requirements of each onboard device based on the received data; dynamically allocates data transmission bus resources based on the evaluation results, and assigns matching data transmission buses, processing priorities, and storage resources to each onboard device.

[0092] The specific steps are as follows:

[0093] 1) Network initialization and configuration:

[0094] 1. During the AUV system startup phase, the network topology is initialized first;

[0095] 2. Determine the main control unit (PC104) as the network center node, responsible for management and scheduling;

[0096] 3. Each functional module (such as sensors, actuators, etc.) serves as a network edge node and is connected to the main control unit through a high-speed communication bus (such as Ethernet or CAN bus);

[0097] 4. Assign a unique network address and communication port to each functional module based on the system configuration.

[0098] 2) Determine the load status:

[0099] 1. Real-time monitoring of network performance data, such as latency, packet loss rate, bandwidth utilization, etc.;

[0100] 2. Dynamically adjust network parameters based on performance data to improve communication efficiency and overall system performance;

[0101] 3. Regularly evaluate and optimize network performance to adapt to different task requirements and environmental changes.

[0102] 3) Intelligent distribution equipment:

[0103] 1. When a functional module is to be connected, check whether there is an idle or low-load bus;

[0104] 2. If there is a suitable bus, assign the functional module to the bus;

[0105] 3. If there is no suitable bus, add the functional module to the waiting queue and set up a periodic check mechanism;

[0106] 4. Regularly check the waiting queue and bus load status. Once the bus is idle or the load is reduced, immediately remove the functional module from the waiting queue for allocation.

[0107] 4) Dynamic resource allocation and scheduling:

[0108] 1. Continuously monitor the load of each bus, including the number of real-time data packets and load change rate;

[0109] 2. If the current bus load is too high, select the appropriate bus for switching based on the load conditions of other buses;

[0110] 3. Evaluate the data transmission requirements, processing capabilities, and real-time requirements of each functional module;

[0111] 4. The main control module dynamically allocates resources based on task requirements, the status of each functional module, and evaluation results, allocating appropriate communication bandwidth, processing priority, and storage resources to each functional module;

[0112] 5. When the system load changes, and during task execution, based on real-time feedback and demand changes, re-evaluate the allocation of each functional module, make necessary adjustments to optimize resource utilization, and dynamically adjust resource allocation.

[0113] Combine Figure 7 and Figure 8 As shown in the figure, the method for the main control module to conduct real-time evaluation of the data transmission requirements, processing capacity requirements and real-time requirements of each device is as follows:

[0114] The basic information of the mounted devices is read from the configuration file, and the mounted devices are compound-classified based on the data volume and real-time requirements of the mounted devices; the mounted devices are prioritized based on the classification results to obtain a sorted list.

[0115] The main control module designs a bus selection strategy for the corresponding mounted device based on the load status monitoring results of each data transmission bus and the sorting list; and dynamically selects a matching data transmission bus access for the mounted device based on the bus selection strategy.

[0116] The specific implementation steps of intelligent allocation technology are as follows:

[0117] 1) Get module information:

[0118] 1. Read basic information about the functional module from the configuration file (type, estimated data volume, real-time requirements, etc.);

[0119] 2. Preprocess the read information, such as verifying the integrity and rationality of the data.

[0120] 2) Classification and sorting:

[0121] 1. Design a composite classification method based on data volume and real-time requirements;

[0122] 2. Prioritize the classified functional modules to form a sorted list.

[0123] 3) Select bus access:

[0124] 1. Real-time monitoring of the load status of each CAN bus (such as bandwidth occupancy, delay time, etc.);

[0125] 2. Design a bus selection strategy based on the communication requirements of the functional modules and the physical characteristics of the bus;

[0126] 3. Implement the bus selection algorithm to select the most suitable bus from the available buses for access.

[0127] 4) Dynamic adjustment mechanism:

[0128] 1. Implement a flexible routing mechanism to dynamically adjust data packet transmission paths based on network status and task requirements;

[0129] 2. Monitor the load of each communication link to avoid network congestion and bottlenecks;

[0130] 3. When it is detected that a link is overloaded, part of the data transmission task will be automatically transferred to other links to achieve load balancing.

[0131] Combine Figures 9 to 11 As shown, the main control module is also used to perform status self-test on the three CAN buses:

[0132] The main control module sends a bus self-test command to each control node through the CAN controller; the status of the CAN bus is determined based on the self-test response returned by each control node. A CAN bus with normal communication is considered normal, while a CAN bus with abnormal communication or no response after timeout is considered faulty.

[0133] For the CAN bus in fault state, the main control module performs fault recovery operations:

[0134] Restart the CAN controller corresponding to the CAN bus in the faulty state and reconfigure the bus parameters of the CAN bus in the faulty state; if the CAN bus in the faulty state recovers successfully, it is judged to be in normal state; otherwise, the CAN bus in the faulty state is marked as a permanent fault state and removed from the AUV system or switched to a backup bus;

[0135] When the CAN bus is marked as a permanent fault state, the main control module switches all the devices on the CAN bus in the permanent fault state to the backup bus and updates the communication configuration information of the AUV system; then the state self-check process is performed until all CAN buses are in normal state;

[0136] The main control module records the information of each status self-check in a log file.

[0137] The specific steps of bus self-test technology are as follows:

[0138] 1) Send self-test command:

[0139] 1. The main control module sends bus self-test instructions to each compartment control node through the CAN controller;

[0140] 2) Determine the simulation status:

[0141] 1. The main control module receives the self-test response from each compartment control node and determines the status of each CAN bus based on the response content:

[0142] Normal: bus communication is normal; Fault: bus communication is abnormal or timeout occurs and no response is received.

[0143] 3) Troubleshooting:

[0144] 1. For a faulty CAN bus, the main control module attempts to perform fault recovery operations:

[0145] Restart the CAN controller;

[0146] Reconfigure CAN bus parameters (such as baud rate, ID range, etc.);

[0147] If the fault recovery operation is successful, the bus is re-marked as normal;

[0148] If the failback operation fails, the bus is marked as permanently failed and removed from the system or switched to a backup bus.

[0149] 4) Bus switching:

[0150] 1. When a CAN bus fault is detected, the main control module immediately triggers the bus switching process:

[0151] Switch the functional modules connected to the faulty bus to other standby buses;

[0152] Update the system's communication configuration information;

[0153] After the bus switching is completed, the main control module performs a self-test operation on the switched bus to ensure that it is working properly.

[0154] 5) Record logs:

[0155] The main control module records the self-test results and fault handling status in the log file, including self-test time, bus name, self-test results, fault handling operations and other information.

[0156] Combine Figure 12 As shown, the main control module is also used to perform device self-tests on all installed devices:

[0157] The main control module sends an access request to the CAN controller corresponding to the mounted device through the CAN bus, and determines that the connection is successful based on the response of the CAN controller; after the connection is successful, corresponding functional checks are performed in turn according to the functions of each mounted device; for mounted devices that fail the initial self-test, the device status is repaired by resending instructions, reconfiguring parameters and re-powering on. For mounted devices that fail to be repaired, they are marked as devices to be repaired.

[0158] The specific steps for the self-test of the modular AUV sensor (onboard equipment) are as follows:

[0159] 1. Start self-test:

[0160] The main control PC 104 starts the self-test program and prepares to perform self-tests on each compartment and equipment.

[0161] 2. Access the core compartment CAN controller:

[0162] The main control PC 104 sends an access request to the core compartment CAN controller via the CAN bus;

[0163] Wait for the response from the core compartment CAN controller to confirm whether the connection is successful;

[0164] If the connection is successful, proceed to the next step; if the connection fails, record the error and try to reconnect (the number of retries can be set).

[0165] 3. Core compartment equipment self-inspection:

[0166] (1) Perform self-tests on the following devices in sequence:

[0167] Depth meter (RS485): Send self-test command, wait for response, and check whether the data is normal;

[0168] Water leakage detection (I / O): read the status and check whether the water leakage signal can be detected normally;

[0169] Jetting mechanism (I / O): Try to activate it and check whether the jettisoning command can be sent normally;

[0170] Power management (I / O): Check the power status to ensure normal power supply;

[0171] Adaptive attitude adjustment mechanism (AD): reads sensor data and checks whether the attitude adjustment is normal;

[0172] GPS (RS232), BeiDou (RS232): Send a request to obtain positioning data and check whether the data is valid;

[0173] Digital radio (RS232), Iridium (RS232): Send a test message to check whether the communication is normal.

[0174] (2) For each device, if the self-test passes, it will be recorded as normal; if the self-test fails, try to resend instructions, reconfigure parameters, re-power on, and other repair methods;

[0175] (3) If the repair fails, the device is marked as requiring manual intervention and the error is recorded.

[0176] 4. Navigation segment equipment self-test:

[0177] Perform self-tests on the inertial navigation (RS232), DVL (RS232), and additional lithium battery (SMBus) in turn; the self-test process and error handling are similar to those of the core compartment equipment.

[0178] 5. Multi-mode auxiliary propulsion equipment self-test:

[0179] Perform self-tests on the front thruster (AD), front vertical thruster (AD), aft thruster (AD), aft vertical thruster (AD), main thruster (AD), and steering gear (AD) in sequence; the self-test process and error handling are similar to the previous ones.

[0180] 6. Bow section load self-test:

[0181] Perform self-tests on the forward-looking sonar (network port), camera (network port), and CTD (RS232) in sequence; the self-test process and error handling are similar to the previous ones.

[0182] 7. Load section equipment self-test:

[0183] Perform self-tests on the laser scanner (network port), multibeam bathymetric sonar (network port), side-scan sonar (network port), shallow subsurface profiler (RS485), low-frequency synthetic aperture sonar (network port), acoustic positioning (RS232), strobe light (I / O), magnetometer (RS232), CCD (network port), and altimeter (RS232) in sequence; the self-test process and error handling are similar to those before.

[0184] 8. Complete the self-test:

[0185] Check the self-test results of all equipment and compartments;

[0186] If all devices pass the self-test, the message "Self-test completed, all devices are normal" is printed;

[0187] If any device fails the self-test and cannot be automatically repaired, the message "Self-test completed, the following devices require manual intervention" is printed, and all devices requiring manual intervention are listed.

[0188] The advantages of the system of the present invention are illustrated below by comparing it with the traditional modular AUV:

[0189] Modular autonomous underwater vehicles (AUVs) are increasingly being used in ocean exploration and underwater operations. The present invention, which introduces a three-way CAN bus and implements flexible networking and self-diagnosis technology, demonstrates significant differences and advantages in intelligent communication technology for modular AUVs compared to traditional approaches.

[0190] Traditional modular AUVs mostly use a single communication bus architecture, which was adequate for a small number of devices and a light communication load. However, as modular AUVs increase in functionality and carry more diverse equipment, the communication bottleneck of a single bus has become apparent, leading to problems such as data transmission delays and slow device response. Furthermore, traditional AUVs often lack flexibility in payload distribution, limiting the maximum utilization of their carrying capacity.

[0191] In contrast, the modular AUV of the present invention, which introduces a three-way CAN bus and implements flexible networking and self-test technology, has shown significant advantages. The setting of the three-way CAN bus not only improves the reliability and stability of communication, but also realizes the dynamic optimization of bus resources through intelligent allocation technology. When a bus is busy, the system can intelligently connect the device to the idle bus, thereby avoiding communication congestion and ensuring the real-time and accuracy of data transmission. At the same time, this technology also breaks through the load limit of traditional modular AUVs. Through intelligent allocation and dynamic adjustment, it maximizes the use of the AUV's carrying capacity, enabling it to carry more and more complex equipment and complete more complex underwater tasks.

[0192] In summary, the present invention, by introducing a three-way CAN bus and realizing flexible networking and self-checking technology, is superior to traditional solutions in terms of communication efficiency, load distribution, and intelligence level, providing new ideas and strong technical support for the development and application of modular AUVs.

[0193] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be employed in conjunction with other described embodiments.

Claims

1. A modular AUV system based on CAN bus flexible networking, characterized by: The AUV system includes the following modules from bow to stern: The bow section module is equipped with a bow section load carrying interface, controls the connection of the carried equipment through the bow section control node, and transmits the data of the carried equipment through three CAN buses and network cables to communicate with the main control module; The front auxiliary propulsion section module is equipped with a front auxiliary propulsion payload loading interface, controls the connection of the loaded equipment through the front auxiliary propulsion section control node, and transmits the data of the loaded equipment through three CAN buses and network cables to communicate with the main control module; The payload segment module is equipped with sensor and actuator mounting interfaces, controls the connection of the mounted devices through the payload segment control node, transmits the data of the mounted devices through three CAN buses and network cables, and communicates with the main control module; The core control segment module is configured with the main control module, as well as the onboard interfaces of key devices, power management, adaptive adjustment mechanism, GPS and navigation system. It controls the connection of onboard devices through the core control segment control node, and transmits the data of the onboard devices through three CAN buses and network cables to communicate with the main control module; The navigation segment module is equipped with a navigation device and an additional lithium battery mounting interface. It controls the connection of the mounted device through the navigation segment control node, transmits the data of the mounted device through three CAN buses and network cables, and communicates with the main control module. The rear auxiliary propulsion section module is equipped with a rear auxiliary propulsion payload carrying interface, controls the connection of the carried equipment through the rear auxiliary propulsion section control node, and transmits the data of the carried equipment through three CAN buses and network cables to communicate with the main control module; The stern module is equipped with interfaces for the main propulsion and steering gear, controls the connection of the onboard equipment through the stern control node, and transmits the data of the onboard equipment through three CAN buses to communicate with the main control module; Adjacent modules of the AUV system are connected via modular interfaces.

2. The modular AUV system based on CAN bus elastic networking according to claim 1 is characterized in that: The bow section control node, front auxiliary propulsion section control node, payload section control node, core control section control node, navigation section control node, rear auxiliary propulsion section control node and stern section control node are respectively connected to the three CAN buses through three CAN controllers; The bow section control node, front auxiliary propulsion section control node, payload section control node, core control section control node, navigation section control node and rear auxiliary propulsion section control node are connected by network cables through switches in sequence. The switch corresponding to the core control section control node is the main switch; the core control section control node is also equipped with an optical terminal to remotely control and debug each module of the AUV system through optical fiber communication.

3. The modular AUV system based on CAN bus elastic networking according to claim 2 is characterized in that: The main control module uses PC104 as the main control unit to manage and schedule system functions based on the received data; The main control module replaces the equipment and communication paths of each module through each control node according to the task instructions to realize the flexible networking mechanism; the equipment carried by each module includes network protocol equipment and CAN bus protocol equipment; The three-way CAN bus forms three independent communication channels between the main control module and each module of the AUV system.

4. The modular AUV system based on CAN bus elastic networking according to claim 3 is characterized in that: The main control module allocates a data transmission bus to the connected device based on the judgment of the load status of the communication network; the communication network is formed by three CAN buses and a network cable; the data transmission bus includes three CAN buses and one network cable; The main control module dynamically adjusts the network parameters of the communication network formed by the three-way CAN bus and the network cable, and performs performance evaluation and optimization of the communication network. The main control module monitors the load status of each data transmission bus and preferentially assigns the device to be connected to the data transmission bus in the idle state; further, if there is no idle data transmission bus, the device to be connected is preferentially assigned to the data transmission bus in the low load state; Furthermore, if there is no data transmission bus in a low-load state, the current load of each data transmission bus is determined, and the device to be connected is preferentially assigned to the data transmission bus with the lowest load rate; Otherwise, the device to be connected will be added to the waiting queue, and the load status of the waiting queue and each data transmission bus will be checked regularly; the data transmission buses will be sorted according to the low-load priority of the load status, and the data transmission bus will be allocated to the current first waiting device to be connected according to the sorting result. The low-load priority of the load status is idle state, low-load state and lowest load rate state in sequence.

5. The modular AUV system based on CAN bus elastic networking according to claim 4 is characterized in that: The main control module also performs dynamic resource allocation and scheduling based on the judgment of the communication network load status: The main control module monitors the load status of each data transmission bus, including the number of real-time data packets and the load change rate; For a data transmission bus whose load rate reaches a set threshold, selecting the devices on board to switch the data transmission bus according to the priority order; The main control module also conducts real-time evaluation of the data transmission requirements, processing power requirements, and real-time requirements of each onboard device based on the received data; dynamically allocates data transmission bus resources based on the evaluation results, and assigns matching data transmission buses, processing priorities, and storage resources to each onboard device.

6. The modular AUV system based on CAN bus elastic networking according to claim 5 is characterized in that: The main control module conducts real-time evaluation of the data transmission requirements, processing capacity requirements, and real-time requirements of each device as follows: The basic information of the mounted devices is read from the configuration file, and the mounted devices are compound-classified based on the data volume and real-time requirements of the mounted devices; the mounted devices are prioritized based on the classification results to obtain a sorted list.

7. The modular AUV system based on CAN bus elastic networking according to claim 6 is characterized in that: The main control module designs a bus selection strategy for the corresponding mounted device based on the load status monitoring results of each data transmission bus and the sorting list; and dynamically selects a matching data transmission bus access for the mounted device based on the bus selection strategy.

8. The modular AUV system based on CAN bus elastic networking according to claim 7 is characterized in that: The main control module is also used to perform self-check on the status of the three CAN buses: The main control module sends a bus self-test command to each control node through the CAN controller; the status of the CAN bus is determined based on the self-test response returned by each control node. A CAN bus with normal communication is considered normal, while a CAN bus with abnormal communication or no response after timeout is considered faulty. For the CAN bus in fault state, the main control module performs fault recovery operations: Restart the CAN controller corresponding to the faulty CAN bus and reconfigure the bus parameters of the faulty CAN bus; If the CAN bus fault in the fault state is successfully recovered, it is determined to be in normal state; Otherwise, the CAN bus in the fault state is marked as a permanent fault state and removed from the AUV system or switched to a backup bus; When the CAN bus is marked as a permanent fault state, the main control module switches all the devices on the CAN bus in the permanent fault state to the backup bus and updates the communication configuration information of the AUV system; then the state self-check process is performed until all CAN buses are in normal state; The main control module records the information of each status self-check in a log file.

9. The modular AUV system based on CAN bus elastic networking according to claim 8 is characterized in that: The main control module is also used to perform self-tests on all mounted devices: The main control module sends an access request to the CAN controller corresponding to the mounted device through the CAN bus, and determines that the connection is successful based on the response of the CAN controller; after the connection is successful, corresponding functional checks are performed in turn according to the functions of each mounted device; for mounted devices that fail the initial self-test, the device status is repaired by resending instructions, reconfiguring parameters and re-powering on. For mounted devices that fail to be repaired, they are marked as devices to be repaired.

10. The modular AUV system based on CAN bus elastic networking according to claim 3 is characterized in that: The network protocol equipment includes forward-looking sonar, camera, laser scanner, multi-beam bathymetric sonar, side-scan sonar, low-frequency synthetic aperture sonar and CCD; The CAN bus protocol equipment includes CTD, thruster, shallow layer profiler, acoustic positioning, strobe light, magnetometer, altimeter, depth gauge, water leakage detection device, load jettisoning mechanism, power management, adaptive attitude adjustment mechanism, GPS, Beidou, digital radio, Iridium, inertial navigation, DVL, additional lithium battery system and steering gear.

Images