Intelligent control system of automobile airbag folding machine and control method thereof

Abstract

The application discloses an intelligent control system and control method of an automobile safety airbag folding machine, an airbag folding device integrating a folding assembly, a material pressing assembly, a double-side rolling assembly and a turning assembly, and comprises an upper control module, a motion control module, a sensing feedback module and a cooperative control module. The upper control module is internally provided with an editable process formula library, realizes one-key model changing of multiple models of airbags, the sensing feedback module integrates multi-dimensional sensors of force, position, vision, tension and temperature, realizes real-time data acquisition of all processes, and the cooperative control module integrates multi-axis interpolation operation, trajectory conflict avoidance and multi-closed-loop regulation logic, realizes adaptive following of a material pressing angle, synchronous deviation correction of double-side rolling speed, pressure-position mixed closed-loop control and dynamic regulation and control of airbag tension. The application solves the technical problems of poor open-loop control precision, weak cooperation of multiple assemblies, low model changing efficiency, no online quality detection and easy generation of wrinkles and folding deviation of the existing airbag folding device.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology for automotive airbag production equipment, specifically to an intelligent control system and control method for an automotive airbag folding machine, applicable to high-precision automated folding and forming operations of automotive airbags with multiple degrees of freedom and multi-component collaboration. Background Technology

[0002] Automotive airbags are a core component of vehicle passive safety protection. Before leaving the factory, airbags must undergo standardized folding, rolling, and base pressing processes. The folding precision and shape consistency directly determine the airbag's deployment speed, deployment posture, and protective effect during a collision. Currently, airbag folding processes are divided into three types: manual folding, semi-automatic equipment folding, and fully automatic mechanical folding. Manual and semi-automatic methods suffer from poor precision, low consistency, low production efficiency, and high labor costs, making them unsuitable for large-scale mass production.

[0003] Existing fully automated airbag folding equipment mostly employs fixed-logic open-loop point-to-point control or sequential control, which can only achieve mechanical movements along fixed trajectories. This results in low levels of intelligent control and several technical shortcomings: First, the lack of a full-process closed-loop feedback adjustment makes it impossible to monitor key parameters such as pressure force, movement position, and airbag tension in real time. This leads to significant fluctuations in folding quality due to differences in airbag fabric elasticity and laying deviations, resulting in frequent issues such as fold line misalignment, airbag wrinkles, and loose forming. Second, the equipment has poor adaptability. Different vehicle models and installation locations exhibit significant differences in airbag size, folding trajectory, number of folds, and pressure parameters. Changing existing equipment requires manual adjustments to the mechanical structure and weight. First, writing control programs is time-consuming and has a high barrier to entry. Second, the pressing mechanism lacks adaptive adjustment capabilities. During the folding process of the airbag, the direction of the fold line changes dynamically, and the fixed-angle pressing arm cannot adapt to the dynamic fold line, resulting in weak pressing and misalignment during folding. Third, the double-sided rolling mechanism has poor synchronization. The deviation in rotation speed on both sides can easily cause uneven rolling and unilateral deviation of the airbag, which seriously affects the quality of the finished product. Fourth, there is a lack of online quality inspection methods, relying on manual visual inspection or offline sampling inspection, which cannot achieve full inspection and quality traceability, and defective products can easily flow into subsequent processes. Fifth, the lack of a conflict-free prediction mechanism for the movement of multiple components can easily lead to mechanical interference in a confined working space, posing a safety hazard to the equipment.

[0004] In existing publicly available patents and related technologies, some solutions improve folding accuracy through size compensation, while others optimize the mechanical folding structure. However, none of these solutions address the core issues of high-precision coordination of multiple components, dynamic adaptive adjustment, full closed-loop control, and online quality inspection at the control system level. Consequently, they fail to balance folding accuracy, production efficiency, and equipment versatility. Therefore, there is an urgent need to design an intelligent, highly adaptable, high-precision, and traceable airbag folding machine control system and method. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as low control precision, poor coordination, low changeover efficiency, lack of adaptive adjustment, and inability to trace quality, and to provide an intelligent control system and control method for an automotive airbag folding machine. This system achieves closed-loop control of the entire airbag folding process, high-precision coordinated movement of multiple components, adaptive following of the pressing angle, synchronous correction of double-sided rolling and folding, rapid adaptive changeover, and online quality inspection, thereby significantly improving the airbag folding forming precision and production consistency.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An intelligent control system for an automotive airbag folding machine, the folding machine comprising a folding component, a pressing component, two sets of symmetrically arranged rolling and flipping components, and the system comprising a host control module, a motion control module, a sensor feedback module, and a collaborative control module.

[0007] The upper control module serves as a human-machine interaction and parameter storage terminal, including a touch screen human-machine interface and an editable process formula library. The process formula library stores a complete set of process parameters for different models of airbags in batches, including motion curves of each axis, pressure thresholds, speed parameters, tension ranges, standard molding images, etc. It supports adding, modifying and calling parameters, and realizes one-click model change.

[0008] The motion control module is the core of the execution drive, and is divided into three functional units, each corresponding to control the multi-degree-of-freedom motion of different execution components: the pressing control unit realizes the three-dimensional linear movement and Z-axis swing of the pressing component to meet the dynamic pressing angle adaptation requirements; the folding control unit independently controls the four-degree-of-freedom motion of the two sets of folding components to realize the clamping and folding actions that are independently adjustable on both sides; the flipping control unit realizes the translation, lifting and rotation of the flipping component to complete the final shaping and pressing operation. Each unit adopts servo drive to ensure motion accuracy.

[0009] The sensing feedback module constructs a multi-dimensional, full-process perception system. It collects real-time forces from pressing, rolling, and folding through end force sensors, collects precise displacement and rotation speed data through shaft-end position sensors, realizes airbag positioning, fold line recognition, flatness detection, and final quality inspection through top vision sensors, monitors airbag fabric tension in real time through tension sensors, and monitors the working temperature of the pressing head through temperature sensors, providing full-dimensional data support for closed-loop control.

[0010] The collaborative control module is the core computing and control unit of the system. It integrates path planning, multi-axis interpolation, conflict avoidance, PID closed-loop regulation, and synchronous correction algorithm. It can dynamically generate multi-component collaborative motion commands based on process parameters and real-time sensor data, solve the problems of motion sequence conflicts, trajectory deviations, and parameter mismatches of multiple mechanisms, and realize intelligent control of the entire process.

[0011] This invention also provides a control method for an automotive airbag folding machine, based on the aforementioned intelligent control system. The core includes six major steps: parameter loading, pre-processing detection, adaptive pressing and folding, dual-side synchronous rolling, shaping and pressing, and online quality inspection. It is equipped with auxiliary logic for angle adaptation, force-position hybrid closed loop, speed synchronous correction, tension dynamic control, adaptive shape change, conflict avoidance, and temperature compensation, to achieve intelligent and precise control throughout the entire process.

[0012] Compared with the prior art, the present invention has the following outstanding advantages: 1. Comprehensive closed-loop control significantly improves folding quality stability. This invention constructs a multi-sensor fusion feedback system integrating force, position, vision, tension, and temperature, abandoning the traditional open-loop control mode. It performs real-time closed-loop adjustment of pressing force, motion displacement, folding speed, fabric tension, and pressing temperature, effectively offsetting errors caused by differences in fabric material and positioning deviations. This completely solves quality problems such as airbag wrinkles, offsets, and loose forming, ensuring consistency in mass production.

[0013] 2. Adaptive and following pressure angle, dynamically adapting to folding conditions. Based on real-time visual recognition of the dynamic changes in the angle of the airbag to be folded, the swing angle of the pressure arm is corrected in real time, ensuring that the pressure arm is always precisely parallel to the line to be folded. This adapts to the dynamic changes in the shape of the airbag during folding, ensuring that every pressing action is accurate and effective, solving the problems of poor adaptability and pressing failure of traditional fixed-angle pressure.

[0014] 3. High-precision synchronous rolling on both sides ensures excellent forming uniformity. Through closed-loop synchronous control logic that collects rotational speeds on both sides in real time, compares the differences, and corrects deviations symmetrically, the rolling speed deviations on both sides are eliminated in real time, ensuring that the rolling actions on both sides are highly synchronized. This avoids airbag deformation, wrinkles, and displacement caused by rolling too fast or too slow on one side, significantly improving the quality of rolling and forming.

[0015] 4. Modular process formulas enable extremely high changeover efficiency. A pre-set library of process formulas for multiple models allows for one-click parameter recall for changeovers. It also supports custom parameter input and online modification for new models, eliminating the need to adjust mechanical structures and underlying control programs. This significantly reduces changeover costs and enhances equipment versatility and mass production adaptability.

[0016] 5. Multi-axis interpolation coordination + motion conflict avoidance ensures safe and efficient equipment operation. Multi-axis spatial interpolation calculations ensure smooth and accurate motion trajectories of each component, while real-time prediction and proactive correction of motion interference risks resolve conflicts in the coordinated movement of multiple components within confined working spaces, thereby improving equipment operational stability and safety.

[0017] 6. Full-process online quality inspection enables complete quality traceability. Visual image comparison enables online full inspection of folded finished products, replacing the traditional manual sampling method. This accurately identifies defective products while retaining production data, providing data support for product quality traceability and process optimization.

[0018] 7. Intelligent tension and temperature compensation ensures comprehensive molding quality. Real-time adjustment of airbag folding tension prevents fabric stretching, deformation, or loosening and wrinkling; real-time monitoring of the pressure head temperature and thermal compensation control eliminate heat deformation and adhesion issues of the airbag fabric caused by high temperatures, further improving product yield. Attached Figure Description

[0019] Figure 1: Overall architecture block diagram of the intelligent control system.

[0020] Figure 2: Schematic diagram of the control method flow.

[0021] Figure 3: Schematic diagram of the synchronous control principle of folding speed. Detailed Implementation

[0022] For ease of understanding, based on the technical solutions of the present invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solutions of the present invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solutions of the present invention.

[0023] Example 1: Implementation of the Overall System Architecture like Figure 1 As shown, the intelligent control system of the present invention consists of four parts: a host control module, a motion control module, a sensor feedback module, and a collaborative control module. Each module communicates bidirectionally via an industrial bus to achieve data interaction and command transmission.

[0024] The upper control module uses an industrial touch screen as the human-machine interface, supporting functions such as model selection, parameter viewing, parameter modification, equipment status monitoring, fault alarm, and data query. The process formula library has a built-in storage unit that can store complete process parameters for dozens of different specifications of airbags, including parameters such as motion trajectory curves of each axis, target pressure value, rolling speed, tension threshold, flatness standard, and standard final state image.

[0025] The motion control module has three functional units that drive each execution component. All components are controlled by servo motors and high-precision drivers, achieving a position control accuracy of 0.01mm and a speed control accuracy of 0.1r / min, meeting the requirements of high-precision folding operations. The pressing component has four degrees of freedom to adapt to the need for pressing and fixing lines at any angle. The double-sided rolling and folding components are independently controlled to adapt to asymmetrical folding conditions. The flipping component has multiple degrees of freedom to complete precise shaping and pressing.

[0026] The sensing feedback module covers the entire operation process: strain gauge force sensors collect pressure data in real time at a sampling frequency of 1kHz; photoelectric encoders collect the position and speed of each axis in real time; industrial cameras collect operation images at a frequency of 50Hz; tension sensors monitor fabric tension in real time; and temperature sensors collect the temperature of the pressing head in real time, achieving real-time perception of all parameters.

[0027] The collaborative control module serves as the core computing unit, equipped with an embedded industrial controller. It incorporates PID adjustment algorithms, multi-axis interpolation algorithms, image comparison algorithms, synchronous correction algorithms, and conflict avoidance algorithms, coordinating all sensor data and motion commands to achieve intelligent closed-loop control of the entire process.

[0028] Example 2: Implementation of the Overall Control Method like Figure 2 As shown, the complete execution flow of the control method of the present invention is as follows: After the equipment is powered on and initialized, the operator selects the model of the airbag to be processed through the human-machine interface, and the system automatically loads the corresponding process formula parameters. The vision sensor collects images of the airbags laid flat on the workbench and analyzes the flatness of the airbags. If wrinkles or undulations exceed the standard, the system alarms and suspends the operation, prompting manual adjustment; after the flatness is qualified, the system identifies the contour posture of the airbag and calculates the deviation value from the theoretical installation position.

[0029] The collaborative control module corrects the motion trajectory based on the position deviation, drives the folding component to complete the initial folding of the airbag, and simultaneously activates the pressure component for adaptive adjustment: it identifies the angle of the line to be folded in real time, dynamically corrects the swing angle of the pressure arm to ensure that the pressure arm is parallel to the line to be folded, and then activates force-position hybrid control to press the airbag to be folded with the target pressure. The pressure is finely adjusted in real time by the PID algorithm, and the pressing stops immediately after the displacement reaches the set depth to avoid excessive compression and damage to the airbag.

[0030] After the initial folding is completed, the two sets of folding components move synchronously to the clamping positions on both sides of the airbag, clamp the airbag fabric, and start synchronous folding. The system collects the folding speed on both sides in real time, dynamically corrects the speed deviation, and controls the speed difference within a preset threshold to ensure synchronous and uniform folding on both sides. After folding to the target diameter, the folding components pause, the flipping components start, complete the final shaping folding of the airbag, and press the airbag into the base at a uniform speed to complete the assembly.

[0031] After assembly, the vision sensor captures the final image of the finished product and compares it with the standard image in the database in terms of pixels, outline, and shape. It automatically determines whether the folding quality is up to standard. Unqualified products are automatically marked and the data is stored to achieve quality traceability. Example 1

[0032] During the airbag folding process, the fabric shape continuously changes, and the angle of the fold line shifts dynamically in real time. This invention continuously acquires images of the folding area using a vision sensor, extracts the outline of the fold line, and calculates the real-time angle value. The collaborative control module compares the current angle of the pressure arm with the target fold line angle and calculates the angle deviation. When the deviation exceeds the ±1° threshold, a swing adjustment command is immediately output to drive the pressure assembly to precisely swing around the Z-axis for correction. This dynamic closed-loop adjustment continues throughout the entire process until the folding process is completed, ensuring that the pressure arm remains in close parallel contact with the fold line, thus preventing pressure offset and failure issues. Example 2

[0033] like Figure 3 As shown, during the folding process, the left and right folding components operate independently, which can easily lead to speed deviations. This invention uses position sensors to collect the actual speeds on both sides in real time and calculates the real-time speed difference. When the speed difference exceeds a preset synchronization threshold, a symmetrical correction logic is employed: the high-speed side decelerates, and the low-speed side accelerates, providing bidirectional synchronous correction. This allows the speeds on both sides to quickly converge to the target value. Continuous closed-loop control throughout the process ensures no speed difference or attitude deviation during folding, guaranteeing that the airbag folds tightly, evenly, and without wrinkles. Example 3

[0034] This invention employs a force-position hybrid control logic of "pressure priority, position limit," which differs from traditional single-position control or single-pressure control modes. During the pressing operation, the system uses the process target pressure curve as a reference, and the actual pressure is fed back in real time through a force sensor. The PID algorithm dynamically adjusts the servo output torque to ensure accurate and stable pressing force. At the same time, it monitors the pressing displacement in real time. When the displacement reaches the target pressing depth, the pressing action is forcibly terminated. This ensures the pressing and shaping effect while avoiding excessive pressing that could damage the airbag fabric and equipment, thus balancing molding quality and equipment safety. Example 4

[0035] During the folding and rolling process, the tension sensor continuously collects the tension of the airbag fabric. The system compares the actual tension with the preset tension range. When the tension is too low, the component movement speed is increased and the fabric is tightened to eliminate wrinkles. When the tension is too high, the movement speed is reduced and the fabric stress is released to avoid stretching and deformation.

[0036] During the pressing operation, the pressing head and the airbag generate heat through friction. The temperature sensor monitors the temperature in real time. When the temperature exceeds the safety threshold, the system compensates for the temperature by reducing the pressing speed, pausing the operation to dissipate heat, and reducing the friction of the pressing material. This prevents the airbag fabric from deforming or sticking due to high temperature, and ensures the appearance and performance of the finished product. Example 5

[0037] When switching production models, operators can directly call up existing process formulas to achieve one-click model change; for new airbag specifications, a complete set of process parameters can be entered through the human-machine interface, and the system will automatically complete parameter verification and formula storage, without the need for professional programming, making model change convenient and efficient.

[0038] Throughout the entire operation of the equipment, the conflict detection and avoidance unit simulates the motion trajectory of each component in real time, calculates the minimum spacing between mechanisms, predicts interference risks, and actively avoids conflicts by adjusting the motion sequence, correcting the motion path, and reducing the motion speed. This ensures the safety of the coordinated motion of multiple components from the software level and reduces the probability of equipment failure.

[0039] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. An intelligent control system for an automotive airbag folding machine, the folding machine comprising a folding assembly, a pressing assembly, two sets of symmetrically arranged rolling assemblies and flipping assemblies, characterized in that, Also includes: The system comprises a host control module, a motion control module, a sensor feedback module, and a collaborative control module. The upper control module includes a human-machine interface and a process formula library. The process formula library stores folding process parameter sets corresponding to various airbag models. The folding process parameter sets include target position curves, target force curves, target speed ranges, target tension ranges, and standard final state image parameters for each motion axis. The motion control module is communicatively connected to the upper control module and includes a pressing control unit, a folding control unit, and a flipping control unit. The pressing control unit controls the pressing assembly to achieve four-degree-of-freedom motion of linear movement in X, Y, and Z and oscillation around the Z-axis. The folding control unit independently controls two sets of folding assemblies to achieve four-degree-of-freedom motion of linear movement in X, Y, and Z and rotation around the Z-axis. The flipping control unit controls the flipping assembly to achieve three-degree-of-freedom motion of movement in Y-axis, lifting and lowering in Z-axis and rotation around the Z-axis. The sensing feedback module includes a force sensor, a position sensor, a vision sensor, a tension sensor, and a temperature sensor. The force sensor is located at the execution end of each component, the position sensor is located at each motion axis, the vision sensor is located at the top of the folding machine, the tension sensor is located at the clamping part of the folding component, and the temperature sensor is located at the pressing head of the folding component. The collaborative control module is communicatively connected to the motion control module and the sensor feedback module, and has built-in multi-axis interpolation calculation, trajectory conflict avoidance, PID closed-loop adjustment and synchronous correction logic. It is used to generate multi-axis collaborative motion commands based on the process parameter set and real-time sensor data, so as to realize adaptive adjustment of pressing angle, synchronous control of double-sided rolling and folding, force-position hybrid closed-loop adjustment and dynamic control of airbag tension.

2. The intelligent control system for an automotive airbag folding machine according to claim 1, characterized in that, The collaborative control module includes a path planning unit, an interpolation calculation unit, and a conflict detection and avoidance unit. The path planning unit is used to plan the temporal motion trajectory of each component based on the process parameter set of the selected airbag model. The interpolation calculation unit is used to perform spatial interpolation calculations on multiple motion axes and output continuous and smooth multi-axis cooperative motion commands. The conflict detection and avoidance unit is used to predict component motion interference in real time based on the three-dimensional model and planned trajectory of each component, and to avoid conflict by adjusting the motion sequence, correcting the motion path or reducing the motion speed.

3. The intelligent control system for an automotive airbag folding mechanism according to claim 1, characterized in that, The vision sensor is used to collect images of the airbag's flatness, the folding direction during the folding process, and the final folding state, and outputs the airbag's posture, folding angle, and forming state data in real time. The tension sensor is used to collect tension data in real time throughout the entire airbag folding process to prevent the airbag from becoming loose, wrinkled, or excessively stretched and deformed. The temperature sensor is used to collect the working temperature of the pressing head in real time, so as to realize high temperature overheating early warning and cooling compensation control.

4. A control method for an automotive airbag folding mechanism, applied to the intelligent control system described in any one of claims 1-3, characterized in that, Includes the following steps: S1. Model Parameter Loading: In response to the operator's selection command, load the folding process parameter set of the corresponding airbag model from the process formula library; S2. Pre-processing inspection before folding: The flatness data of the flattened airbag is collected by a vision sensor. If the flatness exceeds the standard, an alarm will be triggered and the machine will stop. If there is no abnormality, the positioning process will begin. The airbag outline and posture are identified by a vision sensor, and the deviation between the actual position and the theoretical position is calculated. S3, Adaptive pressing and preliminary folding: The collaborative control module drives the folding component to complete the preliminary folding according to the position deviation and process parameters. At the same time, it drives the pressing component to adaptively adjust the swing angle so that the pressing arm is parallel to the airbag to be folded line in real time, and the force-position hybrid closed-loop control is used to complete the pressing operation. S4. Simultaneous folding on both sides: After the airbag is folded to the preset state, the two sets of folding components are driven to clamp the two sides of the airbag synchronously, and the folding speed on both sides is monitored in real time and synchronous correction is performed to complete uniform synchronous folding. S5. Shaping and pressing: After rolling to the target diameter, drive the folding component to complete the final shaping and rolling of the airbag, and press the airbag roll precisely into the airbag base; S6. Online quality inspection: Collect the final image of the airbag after compression, compare it with the standard final image, and complete the online judgment of folding quality and data traceability.

5. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, The adaptive pressure angle adjustment process in step S3 includes: The vision sensor collects the angle of the folding line of the airbag in real time at a preset frequency, and calculates the deviation between the angle of the folding line and the current angle of the pressure arm. When the angle deviation exceeds the preset threshold, the collaborative control module outputs a swing adjustment command to drive the pressure assembly to swing around the Z-axis in real time to correct the folding line, so that the pressure arm always remains parallel to the dynamically changing folding line.

6. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, The force-position hybrid closed-loop control in step S3 includes: The actual pressure value of the pressing arm is collected in real time by a force sensor, and the pressing displacement data is collected in real time by a position sensor. The control logic of pressure priority and position limit is adopted, and the pressing driving force is adjusted in real time by a PID algorithm to make the actual pressure approach the target pressure curve. When the pressing displacement reaches the target pressing depth, the pressing action is immediately terminated, realizing precise pressure control and displacement limit protection.

7. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, The bilateral roll-up synchronization control in step S4 includes: The position sensor collects the actual rotation speed of the two sets of folding components in real time and calculates the speed difference between the two sides. When the speed difference exceeds the preset synchronization threshold, the high-speed side folding component is decelerated and the low-speed side folding component is accelerated. The two sides are symmetrically corrected so that the two sets of folding components always keep rotating synchronously, ensuring that the airbag folds evenly without deviation.

8. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, It also includes the dynamic control step of airbag tension: During the initial folding and rolling process, the tension sensor collects the airbag tension data in real time. When the tension is lower than the minimum threshold, the component movement speed is increased appropriately to tighten the airbag and eliminate wrinkles. When the tension is higher than the maximum threshold, the component movement speed is reduced to avoid excessive stretching and deformation of the airbag, so that the tension is stabilized within the target range.

9. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, It also includes an adaptive transformation step: The system receives process parameters for the new airbag model from operators through a human-computer interaction interface, and enters these parameters into the process formula library after verifying their legality. Alternatively, it can receive parameter modification instructions to update the process parameters of existing models without adjusting the mechanical structure and underlying control program, thus enabling rapid model changeover.

10. The control method for the automotive airbag folding mechanism according to claim 4, characterized in that, It also includes equipment motion conflict avoidance and temperature compensation steps: Before and during the folding operation, the collision detection and avoidance unit simulates the movement trajectory of each component in real time, predicts the risk of interference and corrects the movement state; the temperature sensor monitors the temperature of the pressing head in real time, and when the temperature exceeds the limit, thermal compensation is achieved by reducing the pressing speed, pausing the operation or adjusting the pressing force to avoid thermal deformation and adhesion of the airbag.

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