A virtual simulation method for an industrial robot production line

Abstract

A virtual simulation method for an industrial robot production line, comprising: 1) constructing a three-dimensional model based on relevant information of the industrial robot production line and importing it into Unity3D to construct an industrial equipment model; 2) designing corresponding model property panels using a UI toolkit based on the functions and properties of different industrial equipment models to control the operating conditions of the models; 3) locally persistently storing the positions and postures of the equipment models in the simulation environment and integrating the constructed equipment models into a multi-type equipment model library; 4) designing a model collision detection function to accurately locate errors in the equipment control program for easy inspection and repair; 5) using a database as an interaction center for virtual and real signals and a storage center for storing user information and historical data of industrial equipment to achieve communication and interaction of various signals and meet the storage requirements of complex system data; 6) constructing a simulation scenario for the industrial robot production line according to the actual situation to complete corresponding virtual commissioning work.

Description

Technical Field

[0001] The present invention designs a virtual simulation method for an industrial robot production line. Background Art

[0002] Since the 21st century, new technologies such as the Internet of Things, cloud computing, big data, mobile communications, artificial intelligence, and machine learning have been widely used in the manufacturing industry, and the integrated innovation of manufacturing systems has continued to develop, forming an important driving force for a new round of industrial revolution. With the continuous increase in China's demand for intelligent manufacturing, digitalization, intelligence, and informatization have become the mainstream direction of industrial development. For China's traditional manufacturing industry, the prerequisite for realizing intelligent manufacturing is to first realize the accurate information mapping of digital-physical dual space, which is inevitably inseparable from the comprehensive application of "digital twins", and the application of digital twins is inseparable from the support of "virtual debugging" technology.

[0003] Digital twin refers to the digital expression of information in the physical world, creating a virtual model in cyberspace that is equivalent to the physical entity. The virtual model can simulate, analyze and test the behavior and characteristics of the physical entity, and feed back the optimized information to the physical world, realizing information interaction between the digital and physical spaces. The application expansion of digital twin technology in the manufacturing industry is "virtual debugging", which refers to debugging the physical equipment program in the digital world, and then formally deploying it after testing and verification, which can speed up the company's R&D speed and reduce the risk of factory operation. The virtual debugging system is a software designed based on virtual debugging technology. Various equipment such as robots, machine tools, conveyor belts, etc. in industrial production lines are made into a model library. Engineers can quickly build a simulation model of the production line according to the on-site situation, collect control signals of real equipment, observe the model operation status and debug online.

[0004] From the perspective of the foreign research status quo, the research and application of "virtual commissioning" have been relatively mature abroad. Many companies have recognized the importance of "virtual commissioning" and developed a series of mature virtual commissioning software, which has enhanced the core competitiveness of enterprises. Although the research on "virtual commissioning" technology in China started relatively late and there are relatively few mature virtual commissioning software, Chinese scholars have also applied the "virtual commissioning" technology in many manufacturing fields. For example, Liu Junhao developed a modular production line fault simulation system based on the Unity3D engine, combining the operation of real devices with computer simulation technology to meet the rapid training needs of talents for automated logistics production lines (Liu Junhao. Research on Modular Production Line Fault Simulation and Virtual Commissioning System Based on Unity3D [D]. Sichuan: Southwest University of Science and Technology, 2020.), but mainly designed a virtual simulation system for the tobacco logistics production line with a simple structure, and its generality is not high. Wang Gang and Guo Yanli applied virtual commissioning technology to the white body production line. They adopted Siemens' virtual commissioning solution, and through a completely virtualized white body production line, shortened the commissioning cycle before mass production of the white body and reduced R & D investment (Wang Gang, Guo Yanli. Application of Virtual Commissioning Technology in White Body Production Line [J]. Journal of Hubei University of Automotive Technology, 2019, 33(4): 38-41.), but the visualization of their system is not realistic enough to meet the requirement of quickly building a production line. For the existing domestic virtual commissioning software, the interaction of virtual and real signals and the control of devices need to be achieved by writing scripts, without a simple operation interface, which requires high capabilities of users, and its interaction performance and general performance are poor; a relatively complete industrial equipment model library has not been established in the simulation system, and secondary development is required for changes to production line equipment, which is not conducive to expansion. However, this method has a production line simulation system. Users can quickly construct the required simulation scenarios through the equipment model library and property panel, etc., and can drive the operation of the simulation model through the collected control signals, greatly improving the efficiency of commissioning intelligent manufacturing production lines. Summary of the Invention

[0005] The present invention aims to solve the above-mentioned technical problems existing in the prior art and provides a method for quickly constructing a virtual simulation of an industrial robot production line.

[0006] The present invention creates an attribute control panel for the model, designs model collision detection, and constructs an industrial equipment model library, etc. based on the Unity3D engine, and realizes the signal interaction between the physical world and the virtual world through a database. A virtual simulation method for an industrial robot production line according to the present invention is constructed based on the Unity3D engine, simulates the on-site environment of real manufacturing, provides a visual three-dimensional model and a user interaction interface, and mainly includes five parts: establishment of industrial equipment models, design of private panel attributes of models, construction of an equipment model library, design of model collision detection, and use of a database.

[0007] To solve the above technical problems, an embodiment of the present invention provides a method for virtual simulation of an industrial robot production line, including the following steps:

[0008] Step 1: Construct the required 3D models according to the relevant information of the actual industrial robot production line, perform operations such as texture mapping, rendering, and file format conversion, and import them into Unity3D to construct a realistic industrial equipment model;

[0009] Step 2: Design corresponding model property panels for the attributes and functions of different industrial equipment models, and control the running status of the models by operating the property panels;

[0010] Step 3: Use a JSON file to locally persistently store the positions and postures of the equipment models in the simulation environment, and integrate the constructed equipment models into a multi-type equipment model library;

[0011] Step 4: Design a model collision detection function to accurately locate errors in the equipment control program for easy inspection and repair;

[0012] Step 5: Use a database as an interaction center for virtual and real signals and a storage center for storing user information and industrial equipment historical data to achieve communication and interaction of various signals and meet the storage requirements of complex system data;

[0013] Step 6: Based on the above steps, quickly construct an industrial robot production line simulation scene according to the actual situation of the production line to complete the corresponding virtual commissioning work.

[0014] Among them, the specific content of Step 1 includes:

[0015] First, perform isometric modeling of industrial equipment in SoildWorks software, then import the built model files into 3DMax software for texture mapping and rendering, and then convert the processed models into the FBX file format supported by the Unity3D engine.

[0016] The industrial equipment commonly used in the robot production line can be classified into robots, conveyor belts, sensors, lathes, and tool hands according to their functional types. The robot model needs to perform kinematic modeling according to the physical parameters of the actual robot and be able to change its position and posture according to the joint angle data; the conveyor belt model needs to be able to control the conveying speed and direction, the sensor model needs to be able to release a trigger signal when triggered, the lathe model needs to be able to control the opening and closing of the door, and the tool hand model needs to have functions such as grasping, welding, and grinding.

[0017] Among them, the specific content of Step 2 includes:

[0018] The property panel is developed through UGUI in the Unity3D engine. UGUI has significant advantages in aspects such as event mechanism, running efficiency, and adaptive system. The basic elements it provides include canvases, texts, images, buttons, switches, dropdown menus, masks, sliders, and scroll bars. It also provides a powerful EventSystem event system to manage UI elements;

[0019] The property panels in the simulation system are all achieved through the combination of basic elements, and a simple and easy-to-operate interface is arranged according to the types and functions of the devices. When dragging a model icon from the device model library, the system will automatically parse the corresponding configuration file of the icon to obtain the type, ID, and path information of the dragged model, so as to load the model and clone the model's UI panel, and save the panel and the model ID as key-value pair data. When the mouse clicks on a model in the scene, the clicked model ID is matched with the saved ID. If the matching result is consistent, the property panel corresponding to the ID will be displayed, otherwise the panel will be hidden;

[0020] Each model in the model warehouse is equipped with its own property panel, and the property panel needs to use different UI controls according to the characteristics of the physical device and control different functions of the model.

[0021] Among them, the specific steps of step three include:

[0022] Use a JSON file to store the data information of the models in the simulation environment, which has the functions of archiving and reading files. When archiving, traverse the model objects existing in the scene, and serialize the configuration information such as the ID, name, category, and introduction of the model, as well as the position coordinates and rotation coordinates. The serialized JSON string file can be opened and edited again on any PC equipped with the simulation system. When reading the file, traverse the JSON string file, perform deserialization operations on the data in the file, load the corresponding device models and property panels according to the parsed configuration information, and determine their postures according to the position coordinates and rotation coordinates, and finally reproduce the simulation scene when saving;

[0023] If the model in the scene is deleted, the JSON file will correspondingly delete the data information of the model; if a new model is added to the scene, the configuration information and coordinate information of the newly added model will be added to the JSON file; if the position and posture of the model in the scene change, the coordinate data of the model in the JSON file will be correspondingly modified;

[0024] Finally, add all the device models with attached property panels and data information into the model warehouse to form a complete industrial device model library.

[0025] Among them, the specific steps of step four include:

[0026] Design of collision detection for the model using the bounding box method. The bounding boxes provided by the Unity engine, such as spheres, cubes, and capsules, are combined with the working space and warning area of each axis of the robotic arm for detection; first, collision boxes are created for each joint axis of the robotic arm according to the shape and working safety area, and when a collision occurs in the collision box, the corresponding function event is triggered; in the function response event, the label of the object contacted by the robotic arm is judged. If the object label is not the working target object of the robotic arm, it is determined that a collision has occurred; if a collision occurs, the simulation is immediately stopped, a warning message is issued, and the collision event caused by a program error is promptly responded to and relevant processing is carried out.

[0027] Among them, the specific content of step five includes:

[0028] The MySQL database is used as the storage center for factory business data. The MySQL database tables mainly include factory information tables, equipment information tables, equipment data tables, log tables, user record tables, etc. Among them, the factory information table is the main table, and the relationships with other tables are all one-to-many associations; the Redis database is used as the interaction center for physical signals and virtual signals. Data such as the control device I / O signals and robot joint angles in the data acquisition software will be stored in Redis in the form of key-value, and the data values are refreshed in real time according to the running status of the control program.

[0029] The simulation system will read the data values saved in the database in real time, drive the simulation to run through the actual signal values, and save the simulation running status in the database in the form of key-value; the data acquisition software synchronously obtains the running status of the simulation model from the interaction center and feeds it back to the actual control device, so as to realize the signal interaction between the physical world and the virtual environment.

[0030] Among them, the specific content of step six includes:

[0031] The models in the device model library can be quickly loaded into the simulation environment by clicking and dragging with the mouse, and then the user can perform the overall layout by means of coordinate positioning; therefore, the required virtual production line can be quickly built only by dragging the models and coordinate positioning, and then the size, position, and posture of the virtual production line can be controlled and adjusted by operating the model property panel. Finally, the virtual simulation of the industrial robot production line is realized by combining the model collision detection function and the physical device control signals collected.

[0032] A virtual simulation method for an industrial robot production line of the present invention is built based on the Unity3D engine, simulates the on-site environment of real manufacturing, provides a visual three-dimensional model and a user interaction interface, and is mainly divided into five parts: industrial equipment model establishment, model private panel attribute design, equipment model library construction, model collision detection design, and database information storage and interaction. First, the industrial equipment is modeled in proportion in the SoildWorks software; then the built model file is imported into the 3DMax software for mapping and rendering, and after the processing is completed, the model is converted into the FBX file format and imported into Unity3D. Then, the corresponding private panel attributes are designed for models of different categories through the UGUI control, and text and pictures are used to display the model name and explain its information. Buttons, sliders and rollers can control the movement and posture of models such as mechanical arms. The built models are integrated into a multi-category equipment model library, and the model's icon, name and type and other information are stored in a JSON file, which is convenient for display, modification and update in the simulation scene. In order to respond to program errors in a timely manner and avoid collision events, a model collision detection function is designed, and the collision body component in Unity is used to detect whether a collision occurs between models. If a collision occurs, the simulation is stopped immediately and related processing is performed. The system uses two databases, Redis and MySQL, to store and manage data. C# scripts are written to implement information interaction between the virtual simulation system and the database. Redis reads the IO signals and joint data of the equipment from the data acquisition software and transmits them to the virtual simulation system, while the system returns the IO signals of the model to Redis. The virtual simulation system and MySQL transmit factory information, equipment information, equipment data, user records and logs to each other. In short, a real-time, reliable, simple and easy-to-use virtual debugging method for production lines is constructed, which realizes the virtual debugging function of industrial robot production lines and can verify the feasibility of industrial program design and products.

[0033] The advantages of the present invention are as follows: an industrial equipment model library is designed in the simulation method, including models of robots, conveyor belts, sensors, lathes, tools, etc., which is conducive to the rapid construction of a robot production line simulation environment; a user interaction interface is designed for each model, and the precise control of the model posture and size in the simulation scene can be achieved by operating the model property panel; in the virtual debugging process, the model collision detection can respond to collision events caused by program errors in a timely manner, accurately locate equipment control program errors, discover program design defects, and modify and verify them; the position and posture of the built model in the simulation environment can be locally persistently stored by using a JSON file, that is, the persistent operation of the simulation system is supported; at the same time, MySQL and Redis databases are used to store user information, historical data of industrial equipment, and realize the interaction of virtual and real signals, meeting the storage requirements of complex data of the simulation system. Brief Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, obtaining other drawings based on these drawings still belongs to the scope of the present invention.

[0035] Figure 1 It is a structural block diagram of a method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention.

[0036] Figures 2a to 2c It is a common equipment model diagram in the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention, where Figure 2a is a six-axis robotic arm model diagram, Figure 2b is a conveyor belt model diagram, Figure 2c is a flat jaw model diagram.

[0037] Figure 3 It is an equipment model library diagram in the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention.

[0038] Figure 4 It is a robotic arm model property panel diagram in the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention.

[0039] Figure 5 It is a schematic diagram of the robotic arm bounding box in the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention.

[0040] Figure 6 It is an interaction design diagram between the data acquisition software and the simulation system in the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention.

[0041] Figure 7 It is an industrial robot virtual production line diagram of the method for virtual simulation of an industrial robot production line provided by an embodiment of the present invention. Detailed Embodiments

[0042] The following will further elaborate on the present invention in conjunction with the drawings.

[0043] As Figure 1 shown, it is a virtual simulation method for an industrial robot production line provided by an embodiment of the present invention. This method is constructed based on the Unity3D engine and is mainly divided into five parts: establishment of industrial equipment models, design of model private panel attributes, construction of an equipment model library, design of model collision detection, and storage and interaction of database information.

[0044] The establishment of the industrial equipment model mainly constructs a three-dimensional model according to the relevant information of the industrial robot production line and imports it into Unity3D to build the industrial equipment model. It is necessary to model the industrial equipment proportionally in the SoildWorks software; then import the built model file into the 3DMax software for texture mapping and rendering. After the processing is completed, the model is converted into the FBX file format and imported into Unity3D.

[0045] The design of the model private panel attributes is mainly based on the functions and attributes of different industrial equipment models. The UI toolkit is used to design the corresponding model attribute panel to control the running status of the model; the main method is to use text and pictures to display the model name and description information, and operation buttons, sliders and rollers to control the movement, position and posture of models such as robotic arms.

[0046] The device model library is a three-dimensional model warehouse constructed by integrating all device models. Information such as the icons, names and types of the models is stored in a JSON file, which is convenient for display, modification and update in the simulation scenario.

[0047] The design of model collision detection mainly uses the method of combining bounding boxes with the working space and warning areas of each axis of the robotic arm for detection, which can respond to program errors in a timely manner, avoid collision events, and achieve precise positioning of errors in the device control program, facilitating users to check and repair.

[0048] The storage and interaction of database information mainly use Redis and MySQL databases in combination to store and manage the data of the system, realize the communication and interaction of various signals, and meet the storage requirements of complex data of the system. The information interaction between the virtual simulation system and Redis and MySQL databases is realized through C# scripts. Redis reads the IO signals and joint data of the device from the data acquisition software and transmits them to the virtual simulation system, while the system returns the IO signal subset of the running model to Redis; data such as factory information, device information, device data, user records and logs can be transmitted between the virtual simulation system and MySQL.

[0049] Finally, the functional modules of each part are combined to build a virtual simulation debugging system for the production line with real-time performance, reliability and simplicity and usability. Users can quickly build a simulated production line by clicking and dragging the mouse.

[0050] As shown in Figure 2 to Figure 7 shown, the virtual simulation method of the industrial robot production line in the embodiment of the present invention will be further described:

[0051] (1) For the common equipment models, first, the industrial equipment is modeled proportionally in the SolidWorks software, and then the built model file is imported into the 3DMax software for texture mapping and rendering. After the processing is completed, the model is converted into the FBX file format supported by the Unity3D engine. Then, the model file is imported into the Unity3D engine, and tools such as C# script programs, UGUI interactive controls, texture mapping, and scene lighting are combined to implement the model simulation function. Finally, all the equipment models are added to the model repository to form an industrial equipment model library. Among them, the six-axis robotic arm model is as shown in Figure 2a shown, the conveyor belt model is as shown in Figure 2b shown, and the flat jaw model is as shown in Figure 2c shown.

[0052] Taking the common six-axis robot as an example, the first three axes of this type of robot are used to describe the end position, and the last three axes are used to describe the end pose. The robot model file converted by 3DMax is imported into Unity3D, and the parent-child relationship, link parameters, and joint variables between the joints are set according to the D-H parameter table. The D-H parameter table is shown in Table 1.

[0053] Table 1 Robot D-H Parameter Table

[0054]

[0055] Since the tool coordinate system TCP is connected to the last axis of the robot, the first three axes and the last three axes of the six-axis robot respectively determine the position and pose of TCP. The forward kinematics solution of the robot is the process of calculating the end pose of the robot based on the joint angles of the 6 axes, and the solution is unique. In the simulation system, the motion trajectory of the robotic arm can be more accurately simulated through the collected joint angle data, improving the accuracy of the software virtual debugging function. The conversion relationship between adjacent links of the robot is shown in Equation (1). Substituting the data in the D-H parameter table into the conversion formula can obtain the conversion matrix of adjacent links.

[0056]

[0057] The conversion matrix of each link of the robotic arm is shown in Equation (2):

[0058]

[0059] Multiplying the conversion matrices of each link of the six-axis robot obtained above in sequence can obtain the conversion matrix of the robot end relative to the base coordinate system The position of the robot tool coordinate system TCP relative to the base coordinate system is (p x , p y , p z) as shown in formula (3); the pose of the robot tool coordinate system relative to the base coordinate system is as shown in formula (4). Through C# script programming supported by Unity3d, a forward kinematics function library for the robot class is developed for the simulation of the tool coordinate system at the end of the robotic arm.

[0060]

[0061]

[0062] (2) Equipment model library, as Figure 3 shown. When the simulation system starts, the system first loads the saved JSON configuration file information, and loads the corresponding resource files according to the parsed data such as model icons, names, types, etc. and displays them classified. If the user needs to create a model in the warehouse in the simulation environment, the user can click the corresponding UI icon with the left mouse button and drag it into the simulation environment. When the left mouse button is released, the system will create the equipment model at the position of the cursor. If the placement angle of the model does not conform to the actual production line situation, the world rotation coordinates of the model can be adjusted by rolling the mouse wheel, and the equipment model will rotate synchronously with the change of the coordinate data. If the placement position of the model does not conform to the actual production line situation, the world coordinates of the model can be adjusted by entering coordinates, and the equipment model will be reloaded at the corresponding coordinate position.

[0063] (3) Model property panel. Each equipment in the equipment model library has a property panel. Taking the robotic arm property panel as an example, as Figure 4 shown. The rotation angle of each axis of the robotic arm is controlled by a progress bar sliding component. The upper and lower areas of the component sliding are set according to the working space of the robotic arm. Moving the slider position can complete the change of the robotic arm pose; the name, description, etc. of the equipment are displayed through a text component; the opening and closing of the database, the kinematic simulation of the robotic arm, the drawing of the trajectory at the end of the robotic arm, etc. are controlled through button controls. In order to more accurately simulate the running pose of the robotic arm, a kinematic control panel is designed to avoid abnormal situations such as the robotic arm reaching singular angles.

[0064] (4) Collision detection by the bounding box method. Detection is carried out by combining bounding boxes such as spheres, cubes, and capsules provided by the engine with the working space and warning area of each axis of the robotic arm. The schematic diagram of the robotic arm bounding box is as Figure 5As shown in the figure. First, create collision boxes for each joint axis of the robotic arm according to its shape and working safety area. According to the characteristics of Unity, if two collision boxes collide, the engine will trigger three response functions, corresponding to the events before, during, and after contact respectively. When the contact state of an object changes, the corresponding function events will be automatically called in the software background script. The function response event is responsible for judging the label of the object contacted by the robotic arm. If the object label is not the working target object of the robotic arm, it is determined that a collision has occurred, and the model simulation is immediately stopped and a warning message is issued.

[0065] (5) Interaction between virtual and real data, the interaction between the data acquisition software and the simulation system is as Figure 6 shown in the figure. The actual signals and virtual signals are interacted through the Redis database. The physical control device I / O signals, robot joint angles, and other data collected by the PLC plugin and robot plugin in the data acquisition software will be stored in the database in the form of key-value pairs, and the data values are refreshed in real time according to the operation of the control program. The simulation system will read the data values saved in the database in real time, drive the simulation to run through the actual signal values, and save the simulation running status in the database in the form of key-value pairs. The data acquisition software synchronously obtains the running status of the simulation model from the interaction center and feeds it back to the actual control device to achieve signal interaction between the physical world and the virtual environment.

[0066] (6) Construction operation of the virtual production line. To build a virtual industrial robot production line in the production line simulation system, first import the equipment models required for the production line from the equipment model library. Drag out the Huibo six-axis robot from the robot warehouse in the equipment model library, drag out the machining center and CNC lathe from the lathe warehouse, drag out the gripper tool from the tool hand warehouse and load it onto the Huibo robotic arm, and drag out static models such as fences, stereoscopic warehouses, robot rails, PC machines, and robot control cabinets from other equipment model warehouses. Then, according to the positions of the equipment in the actual production line, build the virtual industrial robot production line by means of coordinate positioning and dragging the coordinate system. The completed virtual production line is as Figure 7 shown in the figure. After the virtual production line model is constructed, start the relevant functions through the model property panel and connect to the target database, and the virtual production line will run following the collected industrial control signals.

[0067] The above is the control situation of the entire invention. The movement of the model in the Unity3D engine has highly realistic visualization; the design of the industrial equipment model library integrates common equipment models, facilitating users to quickly and efficiently build a simulation scenario of a robot production line; the design of the property panel enables precise control of the simulation model; the design of collision detection makes the system have the timeliness of responding to program errors and the security of accurately locating errors; the use of MySQL and Redis databases meets the system's requirements for complex data storage, realizing the interaction of virtual and real signals and the persistence of business data.

[0068] Implementing the embodiments of the present invention has the following beneficial effects:

[0069] The virtual simulation method of the present invention for an industrial robot production line only requires selecting a model corresponding to the actual industrial equipment from the industrial equipment model library during use, placing it in the simulation scenario, and quickly constructing the required virtual production line through simple operations without actual industrial equipment. Running the script file written in the Unity3D engine can truly display the simulation effect of the industrial production line; by observing the simulation effect, it can be detected whether the industrial robot production line is operating normally. If problems occur, they can also be quickly responded to and processed, facilitating users to check and correct. Using this method can reduce the cost and time of actually building an industrial robot production line, and at the same time ensure the real-time and reliability of the production line simulation effect, greatly improving the work efficiency of users.

[0070] The content described in the embodiments of this specification is only an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms stated in the embodiments. The protection scope of the present invention also extends to equivalent technical means that those skilled in the art can think of based on the inventive concept of the present invention.

Claims

1. A virtual simulation method for an industrial robot production line, comprising the following steps: Step 1: Construct the required 3D models according to the relevant information of the actual industrial robot production line, perform operations such as texture mapping, rendering, and file format conversion, and import them into Unity3D to construct a realistic industrial equipment model; Step 2: Design corresponding model property panels for the attributes and functions of different industrial equipment models, and control the running status of the models by operating the property panels; Step 3: Use JSON files to perform local persistent storage of the positions and postures of the equipment models in the simulation environment, and integrate the constructed equipment models into a multi-type equipment model library; Step 4: Design a model collision detection function to accurately locate errors in the equipment control program for easy inspection and repair; Step 5: Use a database as the interaction center for virtual and real signals and the storage center for storing user information and industrial equipment historical data to achieve communication and interaction of various signals and meet the storage requirements of complex system data; Step 6: Based on the above steps, quickly construct an industrial robot production line simulation scenario according to the actual situation of the production line and complete the corresponding virtual debugging work; The specific content of the said Step 1 includes: First, perform equal-proportion modeling of industrial equipment in SoildWorks software, then import the built model files into 3DMax software for texture mapping and rendering, and then convert the processed models into the FBX file format supported by the Unity3D engine; The industrial equipment commonly used in the robot production line is classified according to functional types, including robots, conveyor belts, sensors, lathes, and tool hands; the robot model needs to perform kinematic modeling according to the physical parameters of the robot and be able to change its pose according to joint angle data; the conveyor belt model needs to be able to control the conveying speed and direction, the sensor model needs to be able to release a trigger signal when triggered, the lathe model needs to be able to control the opening and closing of the door, and the tool hand model needs to have the functions of grasping, welding, and grinding; The said robot is a six-axis robot, and the modeling process specifically includes: Perform equal-proportion modeling of the selected six-axis robot in SoildWorks software, paying attention to the relative position relationship between axes; if a commonly used robot model on the market is selected, accurate model files can be directly obtained through downloading from the official website of the robot company and other means; Import the built model files into 3DMax software for texture mapping and rendering, and then convert them into the FBX file format; Import the robot model file in FBX file format into Unity3D, perform kinematic modeling on the robot model according to the physical parameters of the actual robot, and make it able to change its pose according to joint angle data; the first three axes of the six-axis robot are used to describe the end position, and the last three axes are used to describe the end posture; set the parent-child relationship, link parameters, and joint variables between joints according to the D-H parameter table. The D-H parameter table is as follows: Robot D-H Parameter Table Since the TCP of the tool coordinate system is connected to the last axis of the robot, the first three axes and the last three axes of the six-axis robot respectively determine the position and orientation of the TCP; the forward kinematics solution of the robot is the process of calculating the pose of the robot end according to the joint angles of the 6 axes, and the solution is unique; the conversion relationship between adjacent links of the robot is shown in Equation (1), and substituting the data in the D-H parameter table into the conversion formula can obtain the conversion matrix of adjacent links; The conversion matrix of each link of the robotic arm is shown in Equation (2): Multiply the transformation matrices of each link of the six-axis robot obtained above in sequence to obtain the transformation matrix of the robot end relative to the base coordinate system The position of the robot tool coordinate system TCP relative to the base coordinate system is (p x , p y , p z ), as shown in formula (3); the attitude of the robot tool coordinate system relative to the base coordinate system, as shown in formula (4); through C# script programming, develop the forward kinematics function library of the robot class for the simulation work of the tool coordinate system at the end of the robotic arm; 2. The method according to claim 1, wherein, the specific steps of step two include: The property panel is developed through UGUI in the Unity3D engine; The property panel in the simulation system is realized by the mutual combination of basic elements, and a simple and easy-to-operate interface is arranged according to the types and functions of the devices; when dragging the model icon from the device model library, the system will automatically parse the corresponding configuration file of the icon, obtain the type, ID and path information of the dragged model, so as to load the model and clone the UI panel of the model, and save the panel and the model ID as key-value pair data; when the mouse clicks on the model in the scene, the ID of the clicked model is matched with the saved ID, if the matching result is consistent, the property panel corresponding to the ID will be displayed, otherwise the panel will be hidden; Each model in the model warehouse is equipped with its own property panel, and the property panel needs to use different UI controls according to the characteristics of the physical device and control different functions of the model.

3. The method according to claim 1, wherein, the specific steps of step three include: Use a JSON file to store the data information of the models in the simulation environment, which has the functions of archiving and reading files; when archiving, traverse the model objects existing in the scene, and serialize the configuration information such as the ID, name, category, and introduction of the model, as well as the position coordinates and rotation coordinates. The serialized JSON string file can be opened and edited again on any PC equipped with the simulation system; when reading the file, traverse the JSON string file, perform deserialization operations on the data in the file, load the corresponding device model and property panel according to the parsed configuration information, and determine its pose according to the position coordinates and rotation coordinates, and finally reproduce the simulation scene when saving; If the model in the scene is deleted, the JSON file will delete the corresponding model data information; if a new model is added to the scene, the configuration information and coordinate information of the newly added model will be added to the JSON file; if the position and orientation of the model in the scene change, the coordinate data of the model in the JSON file will be modified accordingly; Finally, add all the device models with attached property panels and data information into the model warehouse to form a complete industrial device model library.

4. The method according to claim 1, wherein, the specific steps of step four include: Design of collision detection for the model using the bounding box method; Detection is carried out by combining bounding boxes such as spheres, cubes, and capsules provided by the Unity engine with the working space and warning area of each axis of the robotic arm; First, collision boxes are created for each joint axis of the robotic arm according to the shape and working safety area. When a collision occurs between the collision boxes, a corresponding function event is triggered; In the function response event, the label of the object contacted by the robotic arm is judged. If the object label is not the working target object of the robotic arm, it is determined that a collision has occurred; If a collision occurs, the simulation is immediately stopped, a warning message is issued, and the collision event caused by a program error is promptly responded to and relevant processing is carried out.

5. The method according to claim 1, characterized in that, the specific steps of step five include: Using the MySQL database as the storage center for factory business data. The MySQL database tables include a factory information table, an equipment information table, an equipment data table, a log table, and a user record table. Among them, the factory information table is the main table, and its relationship with other tables is all one-to-many association; Using the Redis database as the interaction center for physical signals and virtual signals. Data such as the control device I / O signals and robot joint angles in the data acquisition software will be stored in Redis in the form of key-value, and the data values are refreshed in real time according to the running situation of the control program; The simulation system will read the data values saved in the database in real time, drive the simulation to run through the actual signal values, and save the simulation running status in the database in the form of key-value; The data acquisition software synchronously obtains the running status of the simulation model from the interaction center and feeds it back to the actual control device, thereby realizing the signal interaction between the physical world and the virtual environment.

6. The method according to claim 1, characterized in that, the specific steps of step six include: The models in the equipment model library can be quickly loaded into the simulation environment by clicking and dragging with the mouse, and then the user can perform the overall layout by means of coordinate positioning; Therefore, the required virtual production line can be quickly built only by dragging the models and coordinate positioning, and then the size, position, and posture of the virtual production line can be controlled and adjusted by operating the model property panel. Finally, the virtual simulation of the industrial robot production line is realized by combining the model collision detection function and the physical device control signals collected.

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