A simulated intelligent device based on unit-level CPS

Abstract

The present invention relates to a simulated intelligent device based on a unit-level CPS, including a physical space and an information space, wherein the physical space includes: a state perception module for collecting perception data from a physical device; an instruction execution module for controlling the operation of the physical device, and the information space includes: a local database for receiving perception data and control strategies, storing the state information of the physical device and the control strategy for the physical device; a data acquisition module for acquiring the perception data during the operation of the physical device; an intelligent computing module for receiving control strategies and perception data, and outputting data supporting intelligent decision-making; a decision control module for generating control instructions for the physical device based on the data supporting intelligent decision-making; and a communication module for realizing data transmission between the intelligent device and the upper control system and between the intelligent devices. Compared with the prior art, the present invention has the advantages of short operation cycle, low time and hardware cost, strong expansibility and flexibility, etc.

Description

Technical Field

[0001] The present invention relates to an analog intelligent device, in particular to an analog intelligent device based on a unit-level CPS. Background Art

[0002] The smart workshop is composed of intelligent equipment such as production equipment, logistics equipment, storage equipment, etc. with autonomous perception and decision-making capabilities. It realizes the interconnection between intelligent equipment and between intelligent equipment and control center through industrial network. With the data of the whole production process as the core, it supports various production management services at the upper level and drives digital, networked and intelligent production and manufacturing. Among them, building intelligent equipment with perception, decision-making, control and communication capabilities is the key to realizing the intelligentization of workshops.

[0003] In current technology, building smart devices for smart workshops can be achieved with the help of unit-level cyber-physical systems (CPS). Unit-level CPS is the smallest unit in the CPS concept. It combines industrial software, perception and control hardware, and communication modules to define smart devices. Its essence is to perform state perception, computational analysis, and behavior control on devices through embedded systems, thereby achieving basic closed-loop operation within smart devices. With the help of industrial networks, multiple unit-level CPSs can be organized to form a system-level CPS, based on which a smart workshop production system with collaborative operation and interconnection of smart devices can be built.

[0004] Existing technical solutions generally build intelligent devices by combining controllers, sensors and actual mechanical devices. When such intelligent devices are applied to academic research, the following problems exist:

[0005] (1) The operation cycle and verification time of smart devices are long, and the time and hardware costs are high;

[0006] (2) The configuration and operation of intelligent devices are complex, which makes it difficult to meet the scalability requirements of academic research on the intelligent workshop experimental platform;

[0007] (3) The application scenarios of intelligent equipment are limited by mechanical devices, which does not meet the requirements of academic research on the organizational flexibility of intelligent workshop experimental platforms. Summary of the invention

[0008] The purpose of the present invention is to provide a simulated intelligent device based on a unit-level CPS in order to overcome the defects of the prior art.

[0009] The purpose of the present invention can be achieved through the following technical solutions.

[0010] According to one aspect of the present invention, a simulated intelligent device based on a unit-level CPS is provided, comprising a physical space and an information space, wherein the physical space comprises:

[0011] The state perception module is used to collect current perception data from physical devices;

[0012] An instruction execution module, used to control the operation of the physical device according to the received control instructions;

[0013] The information space includes:

[0014] A local database is used to receive sensing data and control strategies, store status information of physical devices and control strategies for physical devices;

[0015] A data acquisition module is used to acquire the perception data during the operation of the physical device through a triggered data acquisition method or a periodic acquisition method;

[0016] Intelligent computing module, used to receive control strategies and perception data, and output data that supports intelligent decision-making;

[0017] A decision control module, used to receive data supporting intelligent decision making and generate control instructions for physical devices based on the data;

[0018] The communication module is used to realize data transmission between the intelligent device and the upper control system through the first communication protocol.

[0019] Furthermore, the carrier of the simulated intelligent device is a controller.

[0020] Furthermore, the controller is one or more of a single chip microcomputer and a programmable logic controller.

[0021] Furthermore, the physical space also includes a fault alarm module, which is used to sense physical device failures and trigger a fault repair mechanism.

[0022] Furthermore, the perception data includes one or more of equipment activation status information, operation status information, fault status information, and production status information of the current workpiece of the equipment.

[0023] Furthermore, the trigger data collection method includes one or more of period trigger and event trigger.

[0024] Furthermore, the first communication protocol is an OPC UA communication protocol.

[0025] Furthermore, the physical space also includes a state perception data interface and an instruction execution data interface, the state perception data interface is used to realize data transmission between the state perception module and the data acquisition module, and the instruction execution data interface is used to realize data transmission between the decision control module and the instruction execution module.

[0026] Furthermore, the communication module transmits data with other communication modules simulating intelligent devices through a second communication protocol.

[0027] According to another aspect of the present invention, a method for organizing simulated intelligent devices based on unit-level CPS is provided, wherein the communication module of each simulated intelligent device is connected to the communication module of any other simulated intelligent device, and the communication module of any simulated intelligent device is connected to the upper control system, and the connection mode is one or more of wireless connection and wired connection. The organization method is used to build an intelligent workshop in which one or more simulated intelligent devices operate in coordination.

[0028] Furthermore, the communication module in any of the simulated intelligent devices can perform data transmission with the upper control system via the first communication protocol. The communication module in any of the simulated intelligent devices can perform data transmission with the communication module of any other simulated intelligent device via the second communication protocol.

[0029] Furthermore, the second communication protocol is the TCP / IP communication protocol.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] (1) The simulated intelligent device operation cycle is short, saving time and hardware costs: The present invention uses the simulated physical device operation mechanism to achieve proportional reduction or enlargement of the operation cycle, making the simulated production cycle flexible and adjustable, providing a more flexible experimental platform for scientific research;

[0032] (2) The configuration of simulated intelligent devices is simple and fast, which enhances the scalability of the experimental platform: According to the operation mechanism of the unit-level CPS, the present invention builds simulated intelligent devices with perception, decision-making, control, and communication functions. Data is transmitted between devices through a data bus, and there is no coupling relationship. The devices can be plug-and-play according to actual research needs, and smart workshops of different modes can be built;

[0033] (3) The simulated smart workshop has organizational flexibility: The present invention configures standardized status perception modules, fault alarm modules and instruction execution modules for physical equipment, which can meet the basic needs of different types of equipment. In actual research, the specific smart device types and connection relationships can be defined according to the workshop configuration of the experimental object.

[0034] (4) The intelligent workshop formed by using controllers to simulate the organization of intelligent devices is more in line with the actual situation: There are certain deviations in the operation process of the simulated intelligent workshop compared with the operation process of the ideal simulation model. For example, there is uncertainty in data transmission time, and there is hysteresis in the activation of the internal functional modules of the controller, which leads to fluctuations in the operation time of the simulated physical equipment. This deviation makes the production and operation status of the simulated intelligent workshop closer to the actual workshop. Based on this, the production management research of the simulated intelligent workshop has more practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a structural diagram of a simulated intelligent device based on a unit-level CPS of the present invention;

[0036] Figure 2 This is a diagram of the organizational method of the present invention based on simulating intelligent devices.

[0037] Among them, 1. Information space, 2. Communication module, 3. Local database, 4. Intelligent computing module, 5. Data acquisition module, 6. Decision control module, 7. Physical space, 8. Physical equipment, 9. State perception data interface, 10. State perception module, 11. Fault alarm module, 12. Instruction execution module, 13. Execution instruction data interface, 14. First communication protocol, 15. Upper control system, 16. Second communication protocol, 17. Ethernet. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments 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 should fall within the scope of protection of the present invention.

[0039] Example

[0040] like Figure 1 The simulated intelligent device includes a physical space 7 and an information space 1, wherein the physical space includes:

[0041] A state perception module 10, used to collect current perception data from physical devices;

[0042] The instruction execution module 12 is used to control the operation of the physical device according to the received control instruction;

[0043] A fault alarm module 11 is used to sense physical device faults and trigger a fault repair mechanism;

[0044] The state sensing data interface 9 is used to realize data transmission between the state sensing module 10 and the data acquisition module 5;

[0045] The instruction execution data interface 13 is used to realize data transmission between the decision control module 6 and the instruction execution module 12.

[0046] The information space includes:

[0047] Local database 3, used to receive sensing data and control strategies, store status information of physical devices and control strategies for physical devices;

[0048] The data acquisition module 5 is used to acquire the perception data during the operation of the physical device through a triggered data acquisition method;

[0049] Intelligent computing module 4, used to receive control strategies and perception data, and output data supporting intelligent decision-making;

[0050] A decision control module 6, used to receive data supporting intelligent decision making and generate control instructions for physical devices based on the data;

[0051] The communication module 2 is used to realize data transmission between simulated intelligent devices through the TCP / IP communication protocol, and to realize data transmission between the simulated intelligent device and the upper control system through the OPC UA communication protocol.

[0052] The simulated intelligent device is implemented by means of a programmable logic controller (PLC) that integrates the TCP / IP protocol and the OPC UA protocol.

[0053] like Figure 2 The above is a diagram of the organization method of simulating intelligent devices, wherein 15 is an upper control system, 16 is a second communication protocol, and 17 is Ethernet. Multiple simulated intelligent devices of the same or different types are interacted and shared with the upper control system through a data bus to realize the functions of autonomous negotiation and collaborative decision-making between devices. At the same time, the upper control system realizes the functions of real-time perception of the production status of the workshop and issuing control strategies to guide the production and operation of the workshop. The data bus is realized through Ethernet based on TCP / IP communication protocol and OPC UA communication protocol, and Ethernet interconnects all devices. Among them, the intelligent devices share data and interactively negotiate between devices via the TCP / IP communication interface, and use the remaining device status data and negotiation results for intelligent decision-making of auxiliary devices, and transmit real-time operation data to the upper control system via the OPC UA communication interface and receive the control strategy generated by the upper control system. The overall operation data of the workshop includes the equipment operation status, equipment failure status, workpiece production status, feeding status and workpiece completion status of all physical devices, and its data structure has a standardized definition. The upper control system is built in the host computer, and its functions are all realized in the host computer.

[0054] This embodiment takes three PLCs simulating intelligent machining equipment as an example, assigns different IP addresses to the PLCs to distinguish different devices, organizes the devices using Ethernet, and interconnects them with the host computer to form a simulated intelligent workshop.

[0055] In this embodiment, the simulated intelligent machining equipment includes a buffer and a processing area. The buffer is used to place virtual workpieces waiting to be processed, and the virtual workpiece structure array contains real-time processing status data and process information. The simulated intelligent device senses the current state, and when idle, selects the corresponding workpiece in the buffer to enter the processing area according to the control strategy. After the workpiece is processed, it enters the next device or the discharge port. This embodiment simulates flexible intelligent machining equipment, that is, the same equipment can complete different processes of different types of workpieces, and the processing time is different. The specific process flow is defined by the workshop configuration information imported from the MySQL database in the upper computer when the workshop is initialized. Similarly, equipment fault settings, feeding settings, and work-in-progress settings are also defined by the workshop configuration information.

[0056] The specific configuration information of the workshop includes:

[0057] Table 1 Equipment information table

[0058] Device Name Fault interval / min Fault repair time / min Ma 1500 60 Mb 1735 50 Mc 1256 85

[0059] Table 2 Processing flow chart

[0060]

[0061] Feed setting: Within 31 days, the daily feed is evenly distributed in the interval [6,12], and the delivery period is 30 days.

[0062] Table 3 Work in process information table

[0063] Artifact Type Process Number of workpieces product_a 4 6 product_b 3 10

[0064] The operation cycle of the simulated intelligent workshop is set to 1 / 240 of the actual workshop production cycle. This is used as a benchmark. The specific operation process is as follows:

[0065] 1) Perception. The simulated intelligent device perceives the current status data in real time, including the equipment status, workpiece status, waiting queue and production performance data. Among them, the equipment status data consists of the equipment IP address, fault flag, fault interval time, fault repair time, processing flag, processing workpiece type and name, and current process; the workpiece status data consists of workpiece type, name, current process, waiting flag (waiting in the buffer), processing flag, processing equipment and end processing flag (end all processing processes); the waiting queue data contains the status of all workpieces waiting for processing, and the production performance data includes daily moving steps, daily output and equipment utilization.

[0066] 2) Analysis and decision-making. After acquiring the status data, the information space of the simulated intelligent device analyzes and calculates it. When the device fails, it issues a fault repair instruction to the physical space. When the device is operating normally and idle, the priority of the workpieces in the buffer is calculated and sorted according to the heuristic scheduling rules, and the workpiece with the highest priority is selected. The processing instruction is issued to the physical space and the production status of the workpiece is updated. When the workpiece is processed, the information space updates the workpiece status and sends the workpiece information to the next device according to the process flow, indicating that the workpiece enters the next device for processing. At the same time, the information space receives the workpiece information sent by other devices and adds it to the waiting queue array of the current device, indicating that the workpiece enters the buffer and waits for processing. Among them, the heuristic scheduling rules include first-in-first-out (FIFO), earliest delivery date first (EDD) and shortest remaining processing time first (SRPT). The corresponding rules can be selected according to the specific experimental requirements.

[0067] 3) Execution. After the physical device receives the instruction containing the processing time and the fault repair time, the workpiece processing process and the fault handling process are realized in the processing area through the delay function module of the PLC.

[0068] 4) Communication. The three intelligent processing devices communicate with the host computer through Ethernet, and transmit and share data between devices. The host computer is connected to the Ethernet through the OPC UA communication interface, and obtains the equipment status data, workpiece status data and production performance data in the workshop from the Ethernet. At the same time, the workshop configuration information and heuristic scheduling rule selection strategy are sent to the Ethernet, so that all devices can obtain this data and perform corresponding operations. The intelligent device uses its own IP address as an identifier, accesses the Ethernet through the TCP / IP communication interface, obtains the equipment status data and workpiece status data of other devices from the Ethernet, and completes the reception and transmission of workpiece information.

[0069] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A simulated intelligent device based on unit-level CPS, characterized in that: The invention comprises a physical space (7) and an information space (1), wherein the physical space (7) comprises: A state perception module (10), used for collecting current perception data from physical devices; The instruction execution module (12) is used to control the operation of the physical device according to the received control instruction. The information space (1) includes: A local database (3), used for receiving sensing data and control strategies, storing status information of physical devices and control strategies for physical devices; A data acquisition module (5) is used to acquire the sensing data during the operation of the physical device through a triggered data acquisition method or a periodic acquisition method; An intelligent computing module (4), used for receiving control strategies and sensing data, and outputting data supporting intelligent decision-making; A decision control module (6), used for receiving data supporting intelligent decision making and generating control instructions for physical devices based on the data; The communication module (2) is used to realize data transmission between the intelligent device and the upper control system through a first communication protocol. The carrier of the simulated intelligent device is a controller, The first communication protocol is the OPC UA communication protocol, The communication module (2) performs data transmission with other communication modules simulating intelligent devices through a second communication protocol. The second communication protocol is TCP / IP protocol, Multiple analog intelligent devices of the same or different types interact and share data through the data bus to achieve autonomous negotiation and collaborative decision-making between devices. The upper-level control system is used to achieve real-time perception of the workshop production status and issue control strategies to guide the workshop production operation. The controller is one or more of a single chip microcomputer and a programmable logic controller. The physical space (7) also includes: The fault alarm module (11) is used to sense physical device faults and trigger fault repair mechanisms. The sensing data includes one or more of the following: equipment activation status information, operation status information, fault status information, and production status information of the current workpiece of the equipment. The trigger data collection method includes one or more of periodic trigger and event trigger. The physical space (7) also includes: A state sensing data interface (9) for realizing data transmission between the state sensing module (10) and the data acquisition module (5); An instruction execution data interface (13) is used to realize data transmission between the decision control module (6) and the instruction execution module (12), The simulated intelligent device is used to simulate the intelligent machining equipment. Different IP addresses are assigned to the intelligent machining equipment to distinguish different devices, and the devices are organized by Ethernet, and are interconnected with the host computer to form a simulated intelligent workshop. In the simulation, the simulated intelligent workshop operation cycle is set based on the actual workshop production cycle. The operation process includes: (1) Perception: Simulate intelligent devices to perceive the current status data in real time, including equipment status, workpiece status, waiting queue and production performance data. Equipment status data consists of equipment IP address, fault flag, fault interval, fault repair time, processing flag, processing workpiece type and name, and current process; workpiece status data consists of workpiece type, name, current process, waiting flag, processing flag, processing equipment and end processing flag; waiting queue data contains the status of all workpieces waiting for processing, and production performance data includes daily moving steps, daily output and equipment utilization rate; (2) Analysis and decision-making: After acquiring the status data, the information space of the simulated intelligent device analyzes and calculates it. When the device fails, it issues fault repair instructions to the physical space. When the device is operating normally and idle, it calculates and sorts the priorities of the workpieces in the buffer according to the heuristic scheduling rules, selects the workpiece with the highest priority, issues processing instructions to the physical space, and updates the production status of the workpiece. When the workpiece is processed, the information space updates the workpiece status and sends the workpiece information to the next device according to the process flow, indicating that the workpiece enters the next device for processing. At the same time, the information space receives the workpiece information sent by other devices and adds it to the waiting queue array of the current device, indicating that the workpiece enters the buffer and waits for processing. The heuristic scheduling rules include first-in-first-out, earliest delivery date priority, and shortest remaining processing time priority. (3) Execution: After the physical device receives the instruction containing the processing time and fault repair time, it implements the workpiece processing process and fault handling process in the processing area through the delay function module; (4) Communication: Intelligent processing equipment communicates with the host computer through Ethernet, and transmits and shares data between devices. The host computer is connected to the Ethernet through the OPC UA communication interface, and obtains the equipment status data, workpiece status data and production performance data in the workshop from the Ethernet. At the same time, the workshop configuration information and heuristic scheduling rule selection strategy are sent to the Ethernet so that all devices can obtain this data and operate it. The intelligent device uses its own IP address as an identifier and accesses the Ethernet through the TCP / IP communication interface. It obtains the equipment status data and workpiece status data of other devices from the Ethernet and completes the reception and transmission of workpiece information.

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