This PDF file contains the front matter associated with SPIE Proceedings Volume 12744 including the Title Page, Copyright information, Table of Contents, and Conference Committee Page.

Because of its benefits of high deposition rate and significant economic benefits, particularly for the effective and quick prototyping of big and complicated parts, wire arc additive manufacturing technology has garnered considerable interest from industry and academics. In this paper, the evolution of WAAM technology is reviewed, the macro and micro mechanical attributes of wire arc additive parts are introduced, the techniques used by researchers to reduce anisotropy and enhance mechanical characteristics are presented, and the typical processes of WAAM parts are summarized. Finally, it is projected that WAAM technology would advance. Finally, the development prospect of WAAM technology is anticipated. The findings indicate that there are still many difficulties in the widespread application of WAAM technology, and the key work in the next time will be to improve the automatic nature of additive manufacturing specimens while also maximizing the technological parameters of additive manufacturing.

Flash butt welding is widely used as an effective welding method in the fields of a ship and marine engineering, transportation, oil drilling, and the metallurgical industry. The current flash butt welding machine basically has a large energy consumption, welding process instability, etc. To solve the above problems, this paper proposes a flash butt welding method and designs a DC flash butt welding equipment. Then, this paper uses Solidworks to establish a three-dimensional model of the above-mentioned welding machine. And through the finite element static analysis of the welding machine structure to assist in the design and optimization.

Facing the revolution of aeroengine complex component manufacturing technology, the traditional inspection mode for production process with two-dimension engineering drawing cannot satisfy the growing inspection requirements due to the incoherence with design and manufacturing graphs. To solve the problem, this paper researches the methodology of introducing Model Based Definition (MBD) technology to inspection planning work. The inspection information extraction and organization are carried out directly from the three-dimension digital graph and the measurement path planning is programmed based on the inspection features exported from the information management module. Then the inspection information management and path planning modules are integrated into a UG NX based system supported by a database and web environment to form an application tool. The integrated system makes up for the existing deficiencies in the inspection process of aeroengine complex components and is proven to be available in an actual aeroengine component manufacturing factory.

In order to study the displacement response of the attached lifting scaffold under the action of fluctuating wind, this paper combines the harmonic synthesis method and Kaimal wind speed power spectrum to simulate the fluctuating wind in time, and uses the Newmark-β method to solve the displacement response of the attached lifting scaffold under the action of fluctuating wind load, and analyses the stability of the attached lifting scaffold by comparing the displacement response under the action of fluctuating wind load and static wind load to provide a reference basis for practical engineering. The results show that the top middle of the attached lifting scaffold is the weakest position, and that the displacement response of each node under the action of fluctuating wind load is greater than the displacement response under the action of static wind load. In order to achieve the displacement response bearing value under the action of instantaneous wind load, it is recommended to carry out dynamic analysis in the design verification of actual construction to avoid unsafe measures in actual use.

This paper describes the fabrication method of a PVDF interdigital transducer (PVDF-IDT) suitable for the underwater environments and conducts experiments on the detection of structural defects of underwater structures based on the IDT Rayleigh wave technology. The micro-sized and soft material property of PVDF-IDT has the characteristic of being permanently adhered to the surface of the inspected structure and shows great potential for the construction of lightweight structural health monitoring systems. Therefore, this paper has carried out the Rayleigh wave-structure damage experiment to obtain the empirical formula of surface wave and structural damage, and the empirical formula shows that the surface wave can achieve sub-millimeter precision detection of structural damage.

This paper proposes an innovative Active Coupled Multimodal Robot (ACMR). The unique modal conversion mechanism and active coupled mechanism of ACMR enable the robot to have two types of motion actuators, propeller and wheel, which can move smoothly and efficiently in both the air and on the ground while only using a set of brushless motor drive source. The modal conversion mechanism adopts a turbine worm drive, which facilitates the adjustment of arbitrary whirling arm shapes ranging from 0-90° and allows maintenance without power. The changes in the wheel touchdown timing, robot width, and worm driving torque during the conversion from flight mode to driving mode are theoretically deduced and simulated. The active coupled mechanism employs the combination of a planetary gear train and gear rack mechanism to achieve the active coupling between the three-claw coupler and the propeller. The kinematic relationship between the descending distance of the coupled claw and the modal conversion angle is analyzed, and the maximum descending distance is obtained.

Large-scale ceramic additive manufacturing technology has the advantages of large manufacturing size and high manufacturing accuracy. It is an advanced manufacturing technology with relatively rapid development and can be widely used in aerospace, chemical, energy, and other applications. It is necessary to analyze the types and causes of its forming errors to give full play to its advantages in high-precision manufacturing. This paper took the manufacturing equipment of large-size ceramic additives as the research object, introduced its technical characteristics and manufacturing process, and analyzed the causes and effects of the errors generated in each manufacturing step. The research results can provide the theoretical basis for error compensation research.

The gearboxes, which make up the core component of the metro train bogie, should be lightweight and highly reliable in order to guarantee the security and comfort of train operation. The transient dynamic analysis is performed on a certain type of domestic metro train gearbox as the research object to obtain the load borne by the gearbox body during operation. Then, the strength of the box is analyzed. Finally, a lightweight design is completed using the topology optimization design method under the condition that the strength performance of the box is not reduced. The findings reveal that the weight of the optimized box is 145.8 kg, 12.27% reduction, the maximum deformation is 0.05981 mm, has a 14.46% reduction, and the maximum stress is 66.34 MPa, 7.41% reduction.

In order to analyze the interaction between the grass square laying device and the sandy soil during the laying process, a 3D dynamic finite element model of the blade and the sandy soil was established in ABAQUS finite element analysis software for dynamic display impact simulation analysis. Study the impact on the sandy soil under different sinking speed cases. The results show that: With the sinking of the cutter, the higher the stress value of the sand in contact with the cutter, the more powerful the deformation; during the rolling of the cutter, the stress value at the original point will tend to fall and then rise, and eventually level off. Comparing multiple speeds, when the forward speed is 0.56 m/s, the cutter sinks at 0.35 m/s, and the quality of the grass square laid is the best, which will not cause the collapse of sandy soil. It provides some theoretical reference for the subsequent application in the actual project.

For the problem that it is difficult to determine the type of failure occurring in machining centers, Minitab software is used to process and analyze the failure data, and the type of failure distribution is found to obey the Weibull distribution. Based on the CCR model in the data envelope method, the reliability index is applied to allocate the reliability of the machining center, and according to the practical applicability of the allocation method, the redistribution problem of reliability is better improved, and the reliability level of the whole machine is improved.

According to the characteristics of loop-connection mechanism based on three quadrilateral elements and scissors elements, a construction method of Bricard-like mechanism based on scissors units and loop-connection mechanism is proposed. First of all, based on the analysis of the motion characteristics of the loop-connection mechanism of three quadrilateral units, a preliminary scheme of adding scissors units is put forward. Secondly, the folding and unfolding characteristics of scissors units are analyzed, and different requirements of bars length is put forward according to different characteristics. Finally, the three-dimensional models of Bricard-like mechanism based on scissors units and loop-connection mechanism is established, and its motion modes are analyzed. The proposed construction method can improve the folding ratio of the mechanism and provide some ideas for the design of large-scale folding mechanism.

This paper introduces the design and production process of a full-time four-wheel drive Baja racing car that conforms to the rules of the China Society of Automotive Engineering Baja Competition (2022), including: the determination of design objectives and whole vehicle parameters, as well as the design, production and verification of the frame system, transmission system, suspension system, wheel side mechanism, braking system, steering system, electrical system, etc. CATIA is used to design and assemble the whole vehicle, using simulation After nearly 100 hours of field dynamic testing, the design was optimized and improved according to the actual situation, resulting in a 4WD racing car with high reliability, stability, performance and power.

According to the special needs of deep space exploration, the elastic boom, which is a typical type of the deployment mechanism based on material characteristics has attracted more and more attention. This paper studies the forming technology of the elastic boom. Firstly, this paper introduces the technical connotation of elastic boom; then, the analysis and test results of the forming process are presented; finally, the key issues in the processing of the elastic boom are analyzed, the next research focus is proposed.

Three-dimensional chips require more complex test structures in different test phases, and the test data storage and test power consumption will be greatly increased, so the test cost will be more expensive. To address the above problems, this paper focuses on test data compression and test power consumption and proposes a low-power test data compression scheme for three-dimensional chips. First, for the problem of large test data storage, this paper proposes a very effective test data compression scheme, based on Golomb tour coding compression, which greatly improves the compression rate of test data and reduces the test data storage volume. Second, for the test data compression at the same time, the test shift power consumption and excellent optimization effect, greatly reducing the test power consumption. Finally, this paper proposes a low-power test data compression structure applicable to three-dimensional chip testing and gives the test flow control in each test phase of the three-dimensional chip. The experimental results show that the average compression rate of this scheme reaches 89.72% and the average power consumption is reduced by 86.53%, which effectively reduces the test cost of the 3D chip.

Based on the welding process of 1050/6061 aluminum alloy laser deep penetration welding, a nonlinear transient heat conduction model is established by ANSYS to calculate the temperature field during the welding process. The model considers the change of physical properties of materials with temperature and uses APDL programming language to realize the moving loading of Gaussian surface heat source. The numerical simulation shows that the material temperature can reach the melting point within 0.018s and reach the meteor-like steady process. The temperature gradient at the front end of the heat source is large, and the temperature gradient at the back end is small. In the direction of weld depth, the depth near the melting point of the base metal is 0.55mm; The simulated weld is basically consistent with the weld shape obtained from the test, and the error of penetration width and depth is not more than ± 10%. This study verified the correctness of the simulation method and provided a reference for the welding process and numerical simulation of 1050/6061 aluminum alloy laser deep penetration welding.

In this paper, the digital development and quality control process is studied for the design and manufacturing of complex equipment in the context of digital R&D. For the development phase, the focus is on virtual digital prototype design verification and quality control. For the manufacturing phase, the focus is on 3D prototype process design, digital manufacturing and quality control. The method of multi-source quality BOM information processing is put forward, and has been applied in the development and production of complex equipment. A product quality inspection method based on 3D digital model is proposed, and an application case is given.

Traditional Electrical Discharge Machining (EDM) with internal flushing is often used for machining special-shaped cavities of conductive materials, which improves the machining efficiency but tends to produce sizeable residual material columns on the bottom surface of the workpiece cavity, affecting the machining quality. We propose an adaptive flushing technology for slotted electrode EDM based on gap discharge status detection to solve this problem. An adaptive flushing system was built, and the system’s feasibility was verified through experiments. EDM comparison experiments were designed to study the machining performance of the adaptive flushing slotted electrode EDM system. The experimental results show that the Material Removal Rate (MRR) is increased by about 1.1% and 8.0% when using adaptive flushing compared to continuous flushing and no flushing, respectively. The electrode wear rate (EWR) is reduced by about 38.8% and 4.4% compared to continuous flushing and no flushing, respectively. Therefore, adaptive flushing achieves the dual goal of ensuring processing efficiency and reducing electrode wear.

The production line system of a manufacturing enterprise is a complex discrete-event system with dynamic and complex characteristics. In the traditional text-based production line resource description, the document information is huge, scattered and easily lost. The space for optimization and improvement is small, and it cannot meet the production scheduling and rapid reconfiguration of production lines in complex scenarios. To address the above problems, this paper introduces Model-Based System Engineering (MBSE) into the production line resource system. And a step-by-step modeling method with SysML as the modeling language is proposed to achieve a more accurate and clear model construction of production line resources. Thus, it provides operational objects and certain optimization evaluation capability for production line resource scheduling and reconfiguration.

Safe, reliable, economical, and esthetical stowage bins in civil aircraft can provide passengers with a great space experience and improve the economic efficiency of airlines. This paper proposes a structural design scheme that enables the flexible arrangement of center overhead stowage bins tailored to the specific needs of airlines. Moreover, the principles and contents of the structural design of center overhead stowage bins in civil aircraft are presented, ensuring compliance with the general aircraft design and airworthiness requirements. Static tests are conducted to verify the airworthiness of the designed stowage bins under the limit and ultimate load conditions. This paper provides valuable insights for the structural design and experimental verification of center overhead stowage bins in civil aircraft.

In order to solve the health problems caused by long-term sitting, the structure design and research of the zero-gravity sofa are carried out by using the theory of ergonomics. Starting from the theory of ergonomics, according to the requirements of the zero-gravity function of the sofa, the sofa structure in different states is analyzed. The skeleton structure design, the leg extension structure design, the balanced force structure design, etc. are carried out for modular design analysis and determined the preliminary design scheme of the sofa and checked the sofa in ANSYS Workbench, and finally, a simple structure is designed, which is easy to achieve zero gravity, a space-saving zero-gravity sofa.

According to the requirement of electric upsetting process design for 30MnSi prestressed concrete steel rod (PC steel rod), a set of electric field-temperature field-structure field simulation system was established on deform platform combined with practical production experience. Using this system, the upsetting process of PC steel rod under different technological parameters was simulated, and the forming rule and surface shape of the upsetting head under different technological schemes were analyzed. The forming shape of the upsetting head was taken as the response parameter. Box-Behnken design-response surface method was used to optimize and verify the three main parameters of upsetting temperature, upsetting speed and clamping distance, which can affect the forming quality of the header. The simulation results met the requirements of enterprises on the performance of the prefabricated parts.

The titanium alloy thin-walled parts with rotary structure are often used as the elements for positioning, connecting and load bearing in aerospace field. However, tool wear will appear in the precision turning of such parts by using cemented carbide tools or diamond tools, and the machining accuracy deteriorates. On basis of the study on machining features of titanium alloy thin-walled parts with rotary structure, the cutting error is corrected for tool wear by online compensation, and the machining deformation caused by cutting force is controlled by using diamond turning with ultrasonic vibration in this paper. The elliptical ultrasonic turning is used to machining a typical spaceborne titanium alloy thin-walled cylinder with minimum wall thickness of 3mm, and the roundness error is controlled to 2.83μm for the machined inner hole. The requirement is satisfied on shape accuracy, and the machining feasibility is proved.

As the aging problem gradually aggravates, more and more people pay attention to its travel problem. Aiming at the difficulty of getting on and off a car for people with limited lower limb mobility, this paper designed an auxiliary product for getting on and off a car and made a physical model for feasibility experiment verification. The product is a kind of equipment assembled on the car seat, convenient disassembly and storage. The seat part is divided into two pieces, the upper one can rotate, rotate out when getting on the car, the user after the seat, with the body to the car rotation of the dynamic force, the seat will rotate into the car. At the same time, in order to make people, products and car environment more fit, for the design of ergonomics related theories.

In order to investigate the effect of substrate on the shape of the laser cladding pool, this paper established the numerical simulation model of laser cladding on inclined substrates based on multiphase flow theory. VOF method was adopted to capture the gas-liquid interface. The effect of substrate incline on energy distribution and powder concentration is considered, and the mass and energy input are simulated by adding a source term to the melt pool surface. Finally, comparative experiments are designed to validate the model. The results show that the molten pool showed an obvious inward flow pattern. As the incline angle increases, the laser energy density and powder concentration distribution decreases, and the height and width of the cladding layer decreases. The average deviation between the experimental and simulated values was controlled at 5.8% and 3.7%, respectively, and the model had good explanatory power.

The pressure distribution in the lubricating film between the sealing rings of two sealing rings was calculated based on the Muijderman narrow groove theory firstly, and the film thickness was determined according to the balanced forces on the rotating ring, then the effects of operating conditions, electromagnetic field intensity, and magnetic fluid viscosity on the friction characteristics were investigated. The results indicate that the friction force, friction coefficient and friction torque increase with the increasing rotating speed, intensity of current, volume fraction and diameter of magnetic nanoparticles in magnetic fluid but decrease with the increasing pressure of sealed medium. A smaller film thickness induced by a larger closing force can generate a decrease of friction coefficient, and an increase of friction torque.

With the development of the national economy, there is an increasing demand for lens grinding in fields such as aviation, navigation, and automotive, which requires higher precision and efficiency in lens grinding processes. This has led to higher requirements for the performance and efficiency of JP precision grinding and polishing machines. In order to meet this demand, this paper proposes a design for a JP three-axis precision grinding and polishing machine specifically designed for lens processing. The maximum lens size is 20 centimeters. The machine is designed using SolidWorks software and includes six parts: the bed body component, main shaft component assembly, swing shaft component assembly, electrical control system, surround panel combination, and other accessory combinations (such as hose-type work lights and machine bed iron assemblies). By providing a detailed introduction to these components, the paper explains the design concept, structural characteristics, and working principle of the polishing machine. The main shaft component assembly and swing shaft component assembly include components such as a reduction motor, sliding coupling, main swing shaft sleeve, spherical mirror fixture, and eccentric wheel assembly, which enable the rotation and eccentric motion of the main and swing shafts, thereby achieving precision grinding and polishing of the lens. The surround panel combination assembly controls the main and swing shafts through an electrical control switch and can adjust the amplitude of the swing shaft to meet different processing requirements. The hose-type work light provides illumination and facilitates the operator's observation of the processing situation. The cross-slot semi-sunk head screw nut combination and the machine bed iron assembly are used to fix and support the various components of the polishing machine, ensuring its stability and reliability. With these designs and assemblies, the polishing machine can achieve efficient lens grinding and improve production efficiency.

Aluminum electrolytic capacitors are essential electronic components in circuit systems and are widely used in modern industry. The anode foil is the core component of aluminum electrolytic capacitors. The characteristics of the anode foil oxide film directly determine the performance level of the capacitor. Hydration and formation are critical processes for preparing anode foil oxide films, and there is no systematic review of these two processes. This paper analyzes the current status of domestic and international research on hydration and formation processes, introduces methods to control the process conditions to enhance the oxide film properties, and provides an outlook for future research.

In order to meet new engineering disciplines requirements for talent training and adapt to the development trend of digital electronic technology, FPGA technology is introduced into the experimental teaching of digital electronic technology. In the case of retaining some traditional experiments, a tailor-made pocket experiment board integrating traditional integrated devices and FPGA is independently developed. The experimental board can meet the teaching needs of basic verification experiments, design experiments and comprehensive experiments. In a progressive way, the students' interest in learning is stimulated. In the case of consolidating the students' hardware foundation, the students' modern electronic design ability has been cultivated. The experimental board is easy to carry, and students can develop and design independently without the limitation of time and space, which is conducive to the cultivation of innovative and applied talents.

With the development of science and technology, hole structures are widely used in many industrial fields, such as engine fuel nozzle, turbine blade air film cooling hole, etc. Traditional electrochemical machining can be used to fabricate the hole structures. However, an insulating layer must be coated on the tube electrode. The use of the insulating layer would degrade the quality of the fabricated hole structures. Here, we proposed to fabricate the hole structures by using superhydrophobic tube electrode. First, the superhydrophobic tube electrode was fabricated by laser ablation and low surface energy modification. Then, we investigated the influence of the voltage and feed rate on the radial overcut of the hole structures. Our superhydrophobic tube electrode is expected to be used in the fabrication of the hole structures.

In order to explore the precision milling process via machining parameters on the surface roughness of 95WNiCu tungsten alloy, an orthogonal experiment was designed. XKA715A vertical CNC high-speed milling machine was used and the orthogonal test was conducted which includes 16 set of experiments considering three factors: spindle speed, feeding speed and milling depth. The trend of influence the result with different machining parameters on the surface roughness of the workpiece was obtained by polar difference analysis of the orthogonal test results, which indicates that Tungsten alloy milling parameters should be selected as high speed, reverse milling rate and tiny finish-milling depth.

Aiming at the wearable equipment for individual combat, starting from the functional requirements of individual combat, this article aims to improve the efficiency of individual combat interaction and the cognitive performance of information flow. And it proposes a design idea for individual soldier intelligent wearable information equipment. Including the hardware composition, software composition and intelligent software service design of individual smart wearable equipment, and expounds the application methods of enhanced display, voice interaction, and eye tracking technology in individual wearable equipment. The research and development of smart wearable devices provide a reference for ideas.

The current power grid investment focus from the main network to distribution network, distribution network project investment scale overall rising trend, but the distribution network investment still exists insufficient accuracy, extensive management, the rapid growth of investment scale, the power grid construction lean investment put forward higher requirements, objectively requires power grid construction project cost control more accurate, reasonable and compliance. Feasibility stage is the key stage of engineering investment control, but the power grid company of power transmission and transformation project investment control lack of targeted research, engineering actual investment estimated balance rate is generally higher, combined with the current control status, dig feasibility control, system evaluation index system, scientific and reasonable evaluation, provide reference for distribution network cost accurate control and reference.

The development of upper limb exoskeleton robots is an important stage in the high-quality development of robotics technology. The existing upper limb exoskeleton robots have a single function and complex structure, and their wearability needs to be improved. This paper designs a convenient upper limb exoskeleton robot based on spring energy storage, analyzes the degree of freedom of muscle joints when the human arm moves from the perspective of human bionics, solves the convenience and comfort of users' wearing from the mechanical structure, improves man-machine cooperation, analyzes the calculation principle of joint torque when the human arm moves, optimizes the spring energy storage module, and innovatively adopts the extension spring scheme, Increasing the interchangeability of parts is conducive to the convenient replacement of mechanical structures, and the combination of forearm assistance and boom assistance is used to effectively improve the assistance effect. The effectiveness of the prototype movement is verified by calculating the assistance ratio.

This paper considers the double flexible job shop scheduling problem of both workers and machines with a background of high-efficiency and energy-saving flexible job shop scheduling. Based on this problem, a multi-objective optimization mathematical model of the time index, green production index and worker factor index is established. Aiming at this mathematical model, an improved whale optimization algorithm (MAWOA) is proposed. A two-stage population adaptive strategy is designed, and the calculation of "population life" and the application of neighborhood search are improved. This approach effectively improves the algorithm’s convergence ability and local search capability to achieve a rapid and accurate convergence and ensure the quality of the solution set. Ten kinds of DFJSP benchmark examples are tested, the experimental results show that compared with the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and New Hybrid Genetic Algorithm (NHGA), the MAWOA can obtain better quality solutions, which further shows that the proposed algorithm is effective and superior in solving such problems.

Multi-objective decision making with multiple constraints is a common and difficult problem in intelligent manufacturing and other fields. Through the simulation of management decision-making process, the demand objectives are classified according to attributes, and different target modules are constructed. According to the actual needs of enterprise production, each target module is sorted or combined. Based on the improved genetic algorithm, a Multi-Objective Decision-Making Combination Optimization Model (MODMCOM) with different levels or different structures is established. MODOM fully guarantees the running efficiency of the model and avoids the generation of bad solutions. The most important thing is that this solution model can avoid subjectivity when using traditional decision-making methods to select optimal schemes. By simulating the real process of management decision-making, the model provides a scientific basis for the final scheme selection with the support of intelligent algorithms. The feasibility and effectiveness of the model in solving the problem of multiple conditions and multiple objectives are verified by an example of flexible job shop scheduling decision-making in an enterprise, and the application value of the model in complex systems is illustrated.

For aiming at the safety protection of personnel in the power grid construction process, an integrated construction site monitoring system based on the fusion of visual localization and Ultra-Wideband (UWB) is proposed to realize real-time monitoring of the construction site environment and real-time and accurate three-dimensional positioning of personnel and equipment terminals. Aiming at the problems that UWB signal is easy to be interfered and the construction site vision is easy to be blocked, the fusion algorithm of visual localization and UWB positioning is proposed to make up for the shortcomings of both and achieve more accurate positioning. The integrated monitoring system proposed has been fully verified in the experiment, realizing the accurate three-dimensional positioning of construction site personnel.

A trajectory planning method for automatic shoveling is proposed to achieve energy saving and efficiency improvement when the loader performs automatic shoveling operations. Firstly, the planning of the shoveling trajectory is based on the matching shoveling method. Then the automatic shovel operation test was conducted to obtain relevant operational performance parameters according to different shovel depths. A shovel trajectory optimization method is proposed based on modified parabolic interpolation of test data. The test results of shovel trajectory planning showed that the error was reduced from 9.1% to 0.6% after optimization. And according to the optimized trajectory for automatic shoveling compared with manually controlled shoveling, the operating time increased by 2.29%, the shoveling weight decreased by 3.2%, and the unit shoveling fuel consumption decreased by 11.29%. The test results and calculation process show that the method can quickly find the optimized shoveling trajectory, effectively reducing the operation's energy consumption.

According to the characteristics of the stamping line, this paper designs a 20T intelligent handling robot, which realizes the automatic loading and unloading and handling of stamping sheets. The communication between the stamping line and the handling robot is established, and the stamping line and the handling robot are controlled by using the WCS and the dispatching system to realize the automation of the stamping workshop. Experiments have shown that the use of intelligent handling robots has increased the efficiency of the stamping line by 25%, and the processing accuracy has increased by 33%, which has greatly improved the level of factory automation, provided strong technical support for the overall layout of intelligent factory automation, and promoted intelligent manufacturing. High-end, green and intelligent development of the industry.

In mechanical equipment development and production, manufacturing errors and their distribution are one of the key factors affecting product performance and quality, due to the effect is more evident in the field of engine production, so it is a large demand to develop the instrument of measuring and modelling distribution error of assembly contact surfaces. In this paper, for the main engine parts of the rotary class features, a new measuring and modelling integrated technology is invented, using CMM calibration and compensation algorithm, rapid measurement, and in the machine to measure the point cloud NURBUS surface reconstruction modelling, rapid access to the part surface morphological features. The integration of measurement and modelling reduces the transmission of data, and by processing and modelling simulation of measurement data on the machine, it can provide effective data support and theoretical support for the optimization of assembly process and product performance.

Predicting the upcoming alarm state helps industrial plant operators take timely actions to avoid the negative effects of abnormal conditions. This paper proposes a new data-driven method for trend forecasting in a process variable. The proposed method has two important features: (i) alarm states are predicted in real-time whenever a new trend occurs in the current time sequence, which helps industrial operators take timely actions at the early stage of abnormal conditions; (ii) alarm states are predicted with quantitative probabilities and credibility intervals. By contrast, existing early warning methods are either suitable for specific scenarios where a short prediction step length is needed or cannot provide a quantitative measurement of prediction results. The proposed method firstly captures qualitative trends in the current and historical time sequences and clusters these trends into several categories. Secondly, current and historical trend sequences are obtained according to the cluster results. Finally, recent trends in the current trend sequence are chosen, and alarm states are predicted based on the historical trend sequence having the same sub-sequence. A Bayesian estimator is exploited to calculate the posterior probabilities and their credibility intervals for predicted alarm states. The optimal predicted alarm state is the one with the largest lower bound of posterior probability as a quantitative measurement of prediction accuracy. The effectiveness of the proposed method is illustrated via numerical examples based on a well-accepted benchmark of the Tennessee Eastman process.

Aiming at the requirements of visible light and near infrared information detection in the special industrial environment of high temperature and pollution such as converter steelmaking, a system for collecting optical radiation information is designed from the point of view of high precision and low cost. After the furnace flame is collected by the optical radiation acquisition system, the acquisition and sampling of the radiation light are divided into several spectral segments through the optical fiber spectrum division system and sent to the multi-spectral light intensity composite detection system composed of multiple discrete single chromatogram line probes. Combined with the corresponding hardware and software, the instantaneous spectral line radiation intensity of the furnace flame is detected in real time. The experimental results show that the system can work stably in harsh environment and can monitor the changes of different spectral segments well. There is a good match between the curve of light intensity and the curve of decarbonization rate.

With the rapid development of science and technology, smart cars are widely used in daily life, scientific research, measurement and prediction, industrial production and many other fields. This paper focuses on the in-depth study of sound source localization technology in smart car auditory perception. Based on the research on the existing microphone array, according to the application scenario of the smart car auditory perception system design, the four-element uniform circular array microphone structure is designed, and its receiving model is established. Based on the strong phasor method, and on the basis of the sound intensity vector method, a method of spatial directivity enhancement is proposed to improve the accuracy of sound source localization in the auditory perception system of service robots. This significantly improves the automatic accuracy of sound source localization of the vehicle auditory perception system.

At present, the majority of deep borehole drilling rigs at home and abroad still utilize Asynchronous Motors (AM) with variable-frequency drive as the main power component, which cannot achieve stepless-speed adjustment without decelerating mechanism. In addition, the expenditure of lubrication and maintenance are usually high, and the transmission efficiency is not very ideal. Therefore, this paper proposes a permanent magnet electric direct-drive deep borehole drilling rig (DBZJ40-Z), which firstly adopts Permanent Magnet Synchronous Motor (PMSM) with variable frequency technique to achieve stepless-speed control and direct-drive method to remove the transmission mechanism. Owing to the higher power factor and efficiency of PMSMs, this new type of drilling rig proposed is more energy efficient than the conventional ones equipped with AMs. Furthermore, the utilization of direct-drive mechanism replaces the intermediate transmission gearbox to save a lot of cost of maintenance greatly. Advantages of this new deep borehole drilling rig equipped with PMSMs such as saving energy, easy to maintain and operate, etc. had been verified in several practical applications. Practices proved that this sort of permanent magnet electric direct-drive deep borehole drilling rig equipped with PMSMs must be the future for conventional ones.

This paper is a finite element simulation technology based on error modeling technology. Different from the general ideal model finite element simulation, the contact surface of the 3D model in this model contains geometric error information. The method of constructing interpolating surfaces is used to obtain contact surface features that closely match the actual topography of the part. In the engine casing simulation model, the characteristics of thread fastening are fully considered to apply the load to ensure the accuracy of the calculation of the effect of thread load on stress and deformation. Taking the assembly of aero-engine casing A and aero-engine casing B as an example, ABAQUS software is used to analyze the influence of flange ring uniform loading, ring area loading, and real screw assembly loading on stress distribution. According to the stress distribution and coaxiality change, the screw connection loading mode is simplified, and numerical correction is made.

In this paper, the vibration characteristics of typical components of aero-engine are analyzed, and the calculation and experimental verification are carried out. The influence of the details of the dilution holes on the fatigue life of the structure is obtained. The calculation and test include normal temperature vibration and high temperature vibration. The failure position of the test part is consistent with the maximum position of the analysis response.

In order to realize the path tracking control of agricultural tractors in field operations in complex environments, this paper designs an automatic driving system based on the Luzhong 500A tractor, and studies the path tracking. The tractor automatic driving system consists of a steering module, a shift module and a pedal module. Based on the simplified dynamic model, this paper uses improved LQR controller to achieve path tracking control and carries out Carsim/Simulink joint simulation and field tests. The field test results show that the tractor can achieve autonomous driving, and the simulation results show that the controller can achieve path tracking.

In recent years, deep loosening, rotary tillage, fertilization and other land tillage methods have been vigorously promoted in major crop production areas. Rotary tiller is a kind of tillage appliance which is driven by tractor and rotates the rotary tiller to break up soil and bury straw. During the operation, chemical fertilizers and pesticides can be evenly mixed in the soil and straw can be mixed in the whole tillage layer. The better the mixing of straw and soil, the larger the contact area between straw and soil will not only improve the metabolism of microorganisms in soil, but also improve the decomposition rate of straw. When people study the condition of straw in soil, because the covering condition of straw in soil after rotary tillage is not easy to be observed in the actual working soil, simulation analysis is carried out by EDEM2020 on the way of straw soil mixed into the field. After treatment with EDEM2020, the percentage of surface straw in the total quantity is counted and the percentage of straw mixed into the soil is taken as the evaluation index.

In order to ensure the reliable operation of natural gas station equipment and prevent over-maintenance and under-maintenance of equipment, a fault mode and impact analysis (FMECA) method was proposed. This method is used to analyze the cock valve, calculate its RPN value to finalize and quantitative analysis, and evaluate the reliability of the cock valve objectively. And use the analysis result to adjust the equipment maintenance strategy.

Although elliptical vibration cutting demonstrates the promising application prospects in precision manufacturing process, its material removal and deformation mechanisms have complex time-varying characteristics due to the introduction of tool vibration. Moreover, the coupled characteristics of shearing force on tool rake face and ploughing force on tool flank provide the significant challenges for the experimental explorations of transient cutting mechanisms of elliptical vibration cutting. In this paper, a novel finite element simulation model is proposed to accurately capture the dynamic ploughing interactions between the tool flank and machined waviness in elliptical vibration cutting. The original workpiece surface is intentionally constructed as the ideal representation of the bottom of resultant cutting path for decoupling the ploughing interaction from the material shearing removal. The results indicates that the extrusion and friction forces acting on the flank both show linear dependence with the flank-waviness interference volume, which contributes to the understandings of underlying surface generation mechanism and the establishment of high-precision cutting force in elliptical vibration cutting.

Many industrial processes need to use a large amount of circulating cooling water, and in the process of using circulating water, there will be a lot of bacteria, resulting in pipeline corrosion, equipment blockage and other problems, thus affecting the normal operation of industrial production. Therefore, the circulating cooling water needs to be sterilized. In this paper, a hydraulic cavitation experimental system was established, and five experimental conditions were set up. The bactericidal effect of three groups of different inlet pressures on the colony was studied, and the bactericidal effect of UV and UV cavitation combination was compared. Experiments show that under pure cavitation conditions, increasing inlet pressure within a certain range can significantly improve the colony removal efficiency, and UV cavitation combination has the strongest bactericidal effect, after 60 minutes, the bactericidal rate can reach more than 98%.

In order to effectively and reliably trace the quality of the smart watt-hour meter before supply, all samples for full performance test before supply need to be kept. In this paper, under the conditions of existing warehouses, the layout of smart energy meter warehouse is rationally designed to achieve the maximum storage capacity. Using the Internet of Things technology, we develop an intelligent gyration library that meets the requirements of the actual warehouse, and at the same time, we develop a set of intelligent warehouse management system. Through the binding of RFID tags and measuring instruments, the unique identity of measuring instruments in the warehouse is established, based on RFID group reading technology, the status of measuring instruments in the warehouse is automatically monitored, the warehouse is automatically counted, and the inspection cycle management of measuring instruments is realized. The application of the Internet of Things technology helps to solve the problem of sample management of measuring instruments and enriches the means of management of measuring instruments warehouses.

The SysML model can decompose multiple views of the whole production line system integration model, so that all aspects of its information can be described clearly and completely. However, the SysML model cannot be directly run for verification, so this paper designs SysML model to ARENA model conversion rules to realize the conversion of SysML model to ARENA model and perform the model simulation of the production line. Thus, the verification and simulation work of SysML model is realized.

In order to solve the operational quality problems such as high injury rate, low root removal rate and long residual stems in China's garlic combine harvest, and to improve the performance of root and stem removal operation for garlic combine harvester, a garlic root and stem removal device was developed. A three-factor, three-level orthogonal test was conducted on key parameters affecting the quality of root and stem removal, such as conveying speed, clamping height and clamping angle, through bench tests. The results of the bench test showed that the main and secondary factors affecting the quality of root and stem removal were conveying speed, clamping height and clamping angle, and the better parameter combination was conveying speed of 0.8 m/s, clamping height of 135 mm and clamping angle of 65°. In order to assess the field harvesting quality of the root and stem removal device, a garlic combine harvester was designed, and a prototype was completed for trial production. Through field harvest test, the operational quality of the root and stem removal device was examined in focus. The field test results showed that the device met the quality requirements for garlic combine harvesters.

Mobile grasping robots have broad application prospects in fields such as logistics warehousing, smart homes, crop harvesting, and road garbage collection. They can significantly improve production efficiency, reduce labor costs, and make people's lives more convenient. However, due to complex backgrounds and lighting conditions, mobile grasping robots are prone to missing or misidentifying objects during grasping. This paper proposes a method based on the YoloV5 network, which uses Imgaug data augmentation to enhance and transform image data, as well as lightweight improvements to the YoloV5 network structure. Experimental results show that this method can effectively solve this problem.

The surface hardness of the copper plate is significantly increased after being plated with nickel and cobalt, which is a relatively difficult material to process. Under the same cutting parameters, when machining nickel-cobalt-plated copper plates with the same hardness, the cutting noise along the Y-axis is smaller than that along the X-axis, and the abnormal noise along the Y-axis is slightly smaller. The optimal cutting parameters of the machine tool are obtained through the orthogonal test: cutting the depth is 2.5 mm, the rotation speed is 60 rpm, and the feed rate is 150 mm. The load, current and rotation speed are tested for the optimal parameters obtained from the test. The test results meet the machining requirements of the machine tool, and the machining parameters can be widely used in actual production. The processing problems have improved the machining efficiency of the machine tool.

The riser is a component structure with complex forces in the LNG loading arm, and due to the requirements of installation and structural function, the bottom of the riser needs to open the installation and access hole, which damages the integrity of the riser and puts forward a more severe test for the stability of the riser structure. In this paper, the buckling analysis of the loading arm riser is carried out, and the theoretical formula of the critical buckling load of the riser under the condition of opening defect and reinforcement is calculated by combining the stability theory of the pressure rod and the principle of moment of inertia. The finite element model of open and reinforced riser was established, and the influence law of open hole defect size, reinforcing structural parameters, the relationship between reinforcing and open hole position on the critical buckling response of the riser was analyzed by numerical simulation, which has guiding significance for the design and manufacture of open hole riser of LNG loading arm in engineering.

The technical realization of temperature control system plays a key role in the development of industrial automation. This paper designs a temperature control system with the heating furnace model as the controlled object, the heating furnace water temperature as the data acquisition object and controlled parameters, and the Siemens S7-1500 PLC as the lower computer controller. The PLC ladder diagram programming language in the software carries out the programming design of the lower computer and combines the configuration and monitoring screen of the upper computer to design the configuration monitoring screen. At the same time, the function expansion and operation debugging are carried out to realize the monitoring and automatic control of the temperature data.

This article designs a labview inclination angle data acquisition system based on the vibration monitoring device and photovoltaic station of photovoltaic panel structure. This system can collect data on the inclination angle of photovoltaic panel structures, thereby monitoring the operational status of photovoltaic panels, ensuring their safe, stable, and efficient operation, and improving economic benefits. In addition, the system innovatively combines a three-dimensional image interface for monitoring the tilt angle changes of photovoltaic panels. This software is easy to operate, cost-effective, and can achieve tilt angle testing function.

Developing a maintenance strategy for the whole life cycle of the aero-engine is an essential part of aircraft operation and management. Accurately characterizing the degradation state of aero-engines throughout their whole life cycle and developing corresponding maintenance plans to ensure safe operation and reduce maintenance costs are critical considerations that demand immediate attention. First, the state space is divided based on the main performance monitoring data of the aero-engine, and a hidden Markov model-based engine degradation state characterization model is constructed. Next, the Baum-Welch algorithm is employed to solve the model parameters, and the transition matrix is obtained based on the state transition rules. Subsequently, the optimal maintenance strategy is determined using the policy iteration algorithm with the goal of minimizing the overall life cycle maintenance cost. Finally, the feasibility and effectiveness of the proposed method are verified by utilizing actual detection data of the aero-engine as an example.

In recent years, medical robots are widely used in clinics due to their advantages of small wounds and fast healing after the operation. This paper aims to study a medical robot for iliac bone harvesting and propose a five-degree-of-freedom manipulator. Firstly, iliac bone harvesting surgery and digital twin technology are introduced from control and application aspects. Secondly, a new method of Webots simulation, TF solution and ROS communication mechanism applied in five-degree-of-freedom manipulator is introduced. Experimental results show that the mechanical arm and the Webots simulation model can move synchronously to the designated position, which makes it more accurate to take out bones.

To investigate the impact resistance mechanism of polyurea coated steel composite plate and the influence of polyurea coating position and thickness on the elastic performance of composite plate, the ballistic and simulation tests of polyurea coated steel composite plate were conducted with polyurea coated steel composite plate and Type 53 7.62 mm armor-piercing incendiary ammunition as a typical destructive element. It is found that: the polyurea coating absorbs the kinetic energy of the projectile through glassy hardening. The anti-elastic performance of the steel composite plate coated with polyurea on the back side is better than that of the front side. In order to improve the anti-elastic performance of the composite plate, the thickness of polyurea coated on the front side and back side should be 5 mm and 3mm.

For the synthesis of PMDA and ODA with high comprehensive performance of benzene-based PI, due to its poor solubility, the shrinkage of formed products is generally large, and it is commonly used for thin film use or for molding various structural components using molding method. In order to take advantage of the high comprehensive performance of homobenzene type PI and use it as a structural functional part, direct writing 3D printing provides a new forming method. The preparation of printing ink is achieved by synthesizing its precursor polyamide acid solution, and then the polyimide is formed by thermal amination. At present, the problem of direct writing 3D printing is that its shrinkage rate is very high. It was found that the addition of calcium hydroxide can greatly reduce the shrinkage of the product, and based on this, direct writing 3D printing ink and the formation of porous entities were prepared. Through experiments, the addition of calcium hydroxide as an additive greatly reduces the shrinkage of PAA after hot forming, with a shrinkage rate between 11% and 15%, while maintaining its mechanical strength at 6~10 MPa. The porosity of the formed sample ranges from 25% to 35%, and it has good oil storage and oil retention performance under high-speed conditions. The oil content is close to the porosity, and the oil retention rate is above 93%. But its dry friction coefficient has increased, with a wear rate below 1.5%. Under oil lubrication, the friction coefficient is around 0.2 and the wear rate is below 1.0%. As the content of calcium hydroxide increases, the hardness increases and the wear rate decreases.

Under the background of digital revolution, agricultural autonomous vehicles have made significant progress. Agricultural vehicles have experienced the stage upgrade process from mechanization to automation and then to intelligence. In this process, the development of high-precision positioning technology, automatic driving technology and automatic operation technology provides a solution for the realization of intelligent agricultural vehicle. The application of unmanned agricultural vehicles provides a way to solve the problems such as low labor efficiency, low yield of crops, extensive use of pesticides, and low utilization efficiency of water and soil resources. With the development of science and technology, the agricultural field is moving towards Agriculture 4.0, and unmanned agricultural machinery, as an important component of Agriculture 4.0, plays an irreplaceable role in the production and development of agriculture. The use of unmanned agricultural machinery products to carry out agricultural activities will be the mainstream method adopted by farms. Currently, unmanned agricultural machinery is gradually popularizing, and the economic benefits brought by supply-demand relationship are also driving the continuous development of the agricultural machinery industry, improving its technological level. However, it is undeniable that there are still some technological difficulties that need to be overcome. This paper reviews the latest technological progress in the field of unmanned agricultural vehicles, lists the applications of unmanned agricultural vehicles in agricultural scenarios, analyzes the current status of the field, and prospects for the technological trends and future development of this field.

Parametric resonances of axially moving viscoelastic beams are studied. On the basis of Newton’s second law of motion, governing equation of transverse vibration of axially moving beams is derived, and simple supported boundary condition is assumed. The viscoelastic property of beams is described by three parameter constitutive relation. Parametric vibration of axially moving beams is caused during axial speed subject to harmonic disturbance. For the further analysis, integral transform approach is used to numerically solve the governing equation of axially moving beams. Integral transform approach is numerical method for solving extensively partial differential equation. Integral nonlinear term is dealt with by using Gauss-Legendre integration. Numerical instances showed time histories of linear and nonlinear parametric vibration. The stability of linear system and steady-state response of nonlinear system are investigated.

A ultrasonic vibration drilling experimental platform was established to address the common problem of thermal stress damage in the integrated drilling of CFRP/aluminum alloy laminated structures due to the low heat resistance of carbon fiber reinforced composite materials (CFRP). A comparative analysis was conducted between ordinary drilling and ultrasonic vibration drilling in terms of aluminum alloy chips, drilling temperature, CFRP surface roughness, and CFRP hole outlet quality. Research has shown that the introduction of ultrasonic vibration in drilling can improve the chip breaking effect of aluminum alloys, enhance the heat dissipation conditions of semi enclosed machining environments, and effectively reduce the degree of thermal stress damage at the outlet and wall of CFRP holes.

With the rapid development of numerical control technology, the degree of automation and precision of mechanical processing equipment is getting higher and higher. Hydraulic technology is fully utilized in numerical control machine tools and CNC machining center system. In this paper, the working principle of the hydraulic system of MJ-50 CNC lathe is analyzed in detail, and the common failure phenomenon of the system is analyzed, and the concrete improvement measures are put forward. It is of great significance to reduce and avoid hydraulic failure and is conducive to better and more stable operation of CNC lathe.

The conventional automatic maintenance method for heating defects of high voltage transmission lines mainly uses the aggregate spatiotemporal correlation analysis method to obtain the location characteristics of heating defects, which is vulnerable to the change of defect attributes, leading to the high deviation of automatic maintenance positioning distance. Therefore, it is necessary to design a new automatic maintenance method for heating defects of high voltage transmission lines using flexible maintenance robots. That is to say, a flexible robot maintenance platform for thermal defects of high-voltage transmission lines is constructed, which compensates the positioning error of the automatic maintenance of thermal defects of the flexible maintenance robot, optimizes the movement state of the joint of the automatic maintenance arm for thermal defects of the flexible maintenance robot, and thus realizes the automatic maintenance of thermal defects of high-voltage transmission lines. The experimental results show that under the same maintenance environment, the automatic maintenance positioning distance of the automatic maintenance method for heating defects of high-voltage transmission lines based on the flexible maintenance robot designed in this paper is consistent with the actual distance for heating defects, and there is no automatic maintenance positioning deviation, which proves that the designed automatic maintenance method has good maintenance effect, reliability, and certain application value. It has made a certain contribution to improving the operation reliability of high-voltage transmission lines.

With the rapid development of the fine chemical industry, the proportion of fine chemical production processes in the chemical industry is increasing. However, due to its small scale, intermittent mass production and complex process characteristics, compared with large chemical production processes such as petroleum, petrochemicals and basic chemicals, the comprehensive automation level of domestic fine chemical production processes is generally low. Many enterprises still adopt the traditional mode of local testing instrument control and field, which reduces the degree of precise control of the entire production process. Production safety is not guaranteed, production efficiency is low, affecting the technical level of the domestic fine chemical industry and economic benefits. Therefore, in-depth study of the fine chemical production process control system, to improve the comprehensive automation level of the fine chemical process, to promote the development of fine chemical production, has important significance and experimental value.

In order to improve the safety and stability of mechanical equipment, the structural design of mechanical products is becoming increasingly important. The design of key parts under heavy load is crucial, as the failure of such parts can lead to safety accidents and even casualties. Traditional mechanical testing methods for prototypes are time-consuming and expensive, making it difficult to meet the demands of high-quality and fast design. To address this issue, the development of Computer-Aided Engineering (CAE) technology has facilitated the design and optimization of complex mechanical structures. In this study, we use the finite element modeling and simulation method to analyze the mechanical properties of a forklift manipulator and drive shaft. A 3D model is built based on Abaqus software and simulated on a server. The simulation results provide theoretical and data support for the improvement of mechanical structure. The results show that the maximum Mises stress decreases from 513.5 MPa to 122.5 MPa, which meets the design requirements. Compared with the original structure, the improved manipulator can withstand three times of the load within the allowable stress range. Our research shows that finite element modeling and simulation can provide valuable insights and data to support the improvement of mechanical design.

As a gateway to handle all intranet terminal traffic, SOHO router plays an important role in the network. In this paper, we introduced the security threats faced by SOHO routers, and on this basis, we propose a packet modification method of "Discard-Resend". The method does not affect the normal operation of the router, nor does it affect the normal communication between the two sides. We have done experiments on this packet modification method in several scenarios from the view of network security personnel and network attackers and achieved the desired results. The packet modification method of "Discard-Resend" is a basic work in the security research of SOHO router, and it is of great significance.

Flexible sensors with high sensitivity have shown great potentials in applications such as human motion detection and wearable electronic devices. In this paper, we propose a design of flexible piezoresistive sensors with hole structures that exhibit enhanced sensitivity. The hole structures re-arrange the strain distribution under tensile loadings, and the resulting non-uniform strain distribution amplifies the overall resistive response. The underlying mechanism of the enhanced sensitivity is based on the nonlinear piezoresistive behavior of conductive polymer composites under large strains. Simulation studies accounting for the nonlinear piezoresistivity are performed to investigate the influence of the aspect ratio of an elliptical hole structure on the sensor’s sensitivity. Results show that the design of hole structures increases the piezoresistive response, and a higher sensitivity can be achieved at a smaller aspect ratio. To experimentally validate the design, sensors that are made of exfoliated graphite polymer composites with an elliptical hole of different aspect ratios are prepared and characterized. Results show that the strain sensitivity reaches 7.65 when the aspect ratio decreases to 0.1, improved by two folds compared with the control sample. To demonstrate the performance in monitoring human motions, sensors with and without hole structures are attached on the finger and the wrist to detect the bending and relaxing motion, and enhanced sensitivity is also obtained from the structure with a low aspect ratio. This work provides an effective approach to improve the sensitivity of flexible sensors that are made of piezoresistive polymer composites.

Aviation glass aging is a potential risk, so it is necessary to verify the airworthiness of aviation glass aging. In this paper, the normal aircraft takes aviation composite glass as the research object. First, based on the airworthiness regulations of China's civil aviation, the airworthiness clauses CCAR 23.2235, CAAR 23.2250, CCAR 23.2260 and CCAR 23.2260 of aviation glass are interpreted, and the airworthiness requirements of glass aging verification are given. Based on the requirements of the article, the influence of the ageing environment on the glass was analyzed, and the mechanical properties and thermal stability of the aerospace glass after ageing were verified and analyzed using the MOC2 and MOC4 compliance methods. The results of the study were also used to propose a complete validation process, along with review focus and review recommendations for the validation of composite glass ageing. The final results show that the PMMA pitch section is subjected to greater force and deformation, while the ageing of the composite glass is mainly based on PMMA. As the ageing time increases, the ageing environment changes the internal structure of the Plexiglas, causing the breaking strain and ultimate stress of the glass to decrease significantly, the tensile strength of the glass decreases, the resistance to deformation is weakened, and the thermal stability temporarily increases, with the overall trend increasing first and then decreasing.

With the increasing speed of high-speed train, the application and research of vacuum tube train is imperative. As a necessary device to study the air tightness of vacuum tube train, the design of vacuum air tightness test device needs to consider various factors, which is an important comprehensive scientific problem. Based on the design and analysis of a large vacuum tightness test device, a horizontal vacuum container with an inner diameter of 5.7 m and a straight section of 5.5 m is designed in this paper. In the design, the finite element simulation software ABAQUS was used to simulate the dynamic strength and static strength of the test device under the working state, and the stability analysis was carried out. The results show that the design is reasonable and feasible.

The transmission line has been affected by the natural environment for a long time, and the bolts are prone to frequent vibration, resulting in loosening or falling off. This paper analyzes the loosening mechanism of the screw connection of the transmission tower, carries out the transverse vibration contrast test of the commonly used bolt anti-loosening measures, and compares and analyzes the commonly used bolt anti-loosening performance test standards at home and abroad. Based on the importance of the transmission line and the different operating environment, the grading criteria and differential anti-loosening methods of the transmission tower bolt anti-loosening performance are proposed.

Additive manufacturing (3DP) technology is booming and is gradually widely used in mold manufacturing. It has high-cost performance and less material waste and can well meet the requirements of future manufacturing industry for rapidness, personalization, integration and being lightweight. This paper mainly introduces the current development trend of 3D printing technology and its advantages and disadvantages, as well as the current situation of the integration of related technologies and tire mold production, analyzes and solves the pain points of the process and the technical feasibility, and brings new opportunities for the industry.

The combination of 3D printing and tire mold industry can greatly speed up the production efficiency of tire mold base mold and reduce production costs. This paper mainly introduces the SLA, SLM and other technical principles used in 3D printing tire mold. Starting from the main pain points of the tire mold industry, it lists some problems that need to be solved, compares the advantages of traditional tire mold manufacturing with the field data, and introduces the key technologies of 3D printing tire mold, so as to gradually make the mold production information, digital, refined and intelligent.

In order to study the main bearing load distribution of full-face rock tunnel boring machine under composite rock layer conditions, this paper establishes a cutter load synthesis model and a main bearing load distribution model under composite rock layer conditions in combination with the rock breaking mechanism of the hob, and studies the influence of composite rock layer conditions on the external load and internal load distribution of the main bearing respectively, and proposes the concept of the ratio of the degree of differentiation of composite rock layer based on the influence of composite rock layer on the load distribution of the main bearing. The research results show that the composite rock layer working condition makes the tilting moment of the main bearing increase greatly. With the increase of the ratio of the degree of composite rock layer differentiation, the internal load of the main bearing is gradually transferred from the main thrust roller to the reverse thrust roller. When the ratio of the degree of differentiation of the composite rock layer is greater than 0.262, the reverse thrust roller starts to be stressed.

Silicon carbide (SiC)-based wide-bandgap semiconductor devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs) generate large amounts of heat because of their small size and increasingly high-power density. The junction temperature is the most important index for evaluation of the reliability of these devices. This article proposes a method to study the changes in the forward voltage across the drain (D)-source (S) junction (VDS) under various test conditions from the perspectives of temperature sensitivity, stability, repeatability, and anti-interference properties, with the aim of determining suitable temperature test conditions for SiC MOSFET chips to achieve precise device temperature measurements. The accuracy of the proposed measurement method is verified via comparison with an infrared thermal imaging method and an electrical method. The results obtained show that the error in the SiC MOSFET junction temperature (Tj) measurements when compared with the infrared method and the electrical method is around 1%.

In view of the complex technology status, the complex assembly process and route, being prone to assembly errors, low assembly quality and accuracy, low assembly efficiency, long assembly debugging cycle, we conducted research on intelligent design of assembly process based on digital twin, proposed intelligent design method of assembly process based on digital twin, provided real time intelligent analysis of assembly quality based on digital twin, and assembly process dynamic intelligent optimization design. We verified it by taking the assembly of aircraft wing box as an example. We conducted real time intelligent analysis of assembly quality based on twin data, conducted the intelligent optimization design of process scheme through twin data. The assembly site is controlled by the feedback. The process and assembly are optimized with virtual control. The assembly repetition is reduced, the assembly efficiency is improved, and the assembly quality for the products is enhanced.

In order to solve the problem of recognition and pose estimation of scattered workpieces with similar product shapes in industrial sorting scene, a method combining the improved YOLOv5 workpieces target detection algorithm and 3D point cloud pose estimation algorithm was proposed. RGB images and depth maps were obtained by D435i sensor, and the workpieces in the scattered scene were identified by target detection. The mask of a single workpieces was obtained, the local 3D point cloud was reconstructed through the mask and the aligned depth map, and the pose estimation of the workpieces was carried out by combining the point cloud registration method. The results show that the system can realize the real-time recognition and pose estimation of the workpieces in the industrial scene and meet the industrial requirements.

Physiological parameters during the exercise are instructive. According to the heart rate, body temperature and etc, users could improve their sport performance and have it be beneficial to their health. In addition, such equipment is generally large, inconvenient to carry, and relatively expensive. Therefore, it is of practical significance to study and design a health feedback device that is light weight, easy to carry, and low price, using its physiological parameters to guide exercise. Therefore, this article designs a sports monitoring device based on low-cost sensor, controlling the number of steps, heart rate temperature sensor through MCU, and feeding back the physical parameters such as distance, steps, average speed, heart rate, body temperature and other physiological parameters through LCD in real time to improve the effect of sports. After the hardware circuit is simulated by Multisim, use Altium Designer to design the PCB board of the circuit, and realize the system function with the help of Keil uVision5 modular programming. The system test results show that the system works normally, runs stably, and can accurately provide various physiological parameters. In addition, the whole device is light in weight and high in performance, which can well meet the portability under sports conditions and has certain practical value.

As software products become increasingly complex and product iteration speeds up, there is an urgent need for a more efficient testing method to ensure software quality. Traffic recording playback provides a new interface automation testing method. Based on the traffic recording and playback strategy, we propose a scheme which uses data capture to conduct traffic recording and utilizes firewall user agent (iptables) technology and socket technology to implement Mock. For result verification, we design a comparison result algorithm based on the Diff idea to make the playback verification result more accurate. Compared with some other solutions (GoReplay, Jvm-Sandbox-Repeater, ngx_http_mirror_module, etc.), this solution can support multiple protocols and regression testing without intruding into the application under test. After a large number of tests, the success rate has reached over 96%, the efficiency of interface regression test has increased by 66.7%, and the efficiency of overall test has increased by 40%.

A dry running experiment was to evaluate the anti-oil-interruption ability of a novel cageless bearing, and the failure mechanism was investigated. The results reveal a distinct and singular modification in the bearing temperature profile, characterized by a distinctive shape resembling a "hump" after the oil-interruption. Additionally, the temperature of the outer ring decreased following the oil-interruption due to the newly cageless bearing reduced levels of frictional heat. The experimental data demonstrated that the bearing exhibited a functional lifespan of 88 minutes under dry conditions, indicating a notable anti oil-interruption ability. In summary, the premature failure of bearings can be attributed to significant sliding of the rolling elements, which caused by inadequate lubrication and cyclic contact. This study contributes to understanding the performance of cageless bearings and failure modes under extreme operating conditions, which provides a foundation for further research.

The vibration parameters of the unit have been continuously monitored as the key point, the stable and low vibration value is an important guarantee for the efficient and long period operation of the equipment, which makes the monitoring and diagnosis of vibration and the control of vibration hidden danger become one of the research focuses in the operation and application of the unit. In this paper, the causes of motor vibration hidden trouble in the test of air compressor in SHMTO process are analyzed, and a diagnosis method based on VMS-04B vibration monitoring analysis and balance system is proposed. Using the spectrum analysis in the system, the factors of rotor dynamic balance and mechanical defects are first eliminated, and the basic grouting hollow drum defects are accurately found to be the main cause of unit vibration exceeding the standard. By adding a balance block on the rotor of the motor to rebalance the whole unit, the vibration value can be reduced to the safe range of long cycle operation, and the hidden danger of vibration can be effectively controlled. At the same time, it provides a set of diagnostic methods and treatment schemes for the vibration hidden trouble treatment of similar large units.

In this paper, a three-dimensional model of the pressing of polyetheretherketone (PEEK) particles is constructed using the finite element analysis software MSC. Marc finite element analysis software and based on discrete unit theory to study the displacement of the bulk particles and the variation of the stress-strain of the particles during the pressing process. The effects of press force, lubrication conditions and other process parameters on the relative density of the bulk particles were analyzed. The results show that increasing the pressing force within a certain range can increase the density of the bulk pellets, and that the lubrication conditions need to be improved to further increase the relative density. Numerical simulations are used to obtain the maximum pressing forces for different materials and to provide guidance for improving and optimizing the process parameters in practical production.

Due to the physiological shaking of the human hand during remote operation, there is a certain vibration phenomenon at the end of the robotic arm of the minimally invasive surgery robot, which affects the safety and stability of the surgery. A host-worker tremor suppression strategy based on Kalman filtering is proposed to realize the filtering of tremor signals by combining the conventional digital filtering algorithm and the Kalman filtering algorithm. Simulations and experiments were conducted for the tremor strategy. The results show that the physiological tremor signal is almost completely filtered, and the instability before tremor suppression is smoothly transitioned and corrected in the band after tremor suppression. The host-worker surgical robot's overall performance can be improved, the robotic arm operation can be more stable, and the tremor phenomenon at the robotic arm's end can be successfully suppressed.

To achieve non-invasive, non-contact, and real-time heart rate monitoring, proposed a pulse signal acquisition system using PVDF (Polyvinylidene Fluoride) piezoelectric film. In order to address the issue of errors in heart rate extraction caused by differences in the morphology of pulse signals across individuals or in different states, the K-means clustering algorithm was innovatively used to locate the peak of pulse waveforms in different states and constructed a heart rate data set. Real-time heart rate monitoring by training a large number of pulse signal samples with the proposed CNN-LSTM network model. Experimental results demonstrated that the performance metrics of this model, including the MAE (Mean Absolute Error), RMSE (Root Mean Square Error), and R² (Coefficient of Determination), are 0.2517, 0.3395, and 0.9863, respectively. the maximum error between the proposed system and the standard instrument within three minutes was only 1.55 beats/minute, indicating that the system exhibits high accuracy and reliability, and holds great potential for applications in heart rate detection.

With the advance of the technology of threshing and re-drying, the formula threshing mode guided by the quality homogeneity of tobacco leaves will become the mainstream. A high-quality threshing and re-drying formula module can achieve the stability of the intrinsic quality and physical quality of tobacco leaves, make full use of tobacco leaves, improve the value of tobacco leaves purchased by tobacco re-drying processing enterprises, and give full play to the characteristics and use value of raw material modules. The most important requirement of high-quality threshing and re-drying formula module tobacco is stable quality, and the fluctuation of internal chemical composition is controlled at a low level, that is, the homogenization processing technology of formula module will become the key technology affecting the quality stability. This paper, which used Apriori algorithm, multivariate analysis of variance and principal component analysis, analyzes the parameters of threshing and re-drying technology through some algorithms, which can provide effective guidance for actual production. The results showed that during the threshing stage, the indicators of the one-threshing and third-separation, the one-threshing and fourth-separation, the one-threshing and fifth-separation had the highest impact on the rates of large and medium-sized leaves and stems in the middle of the leaves, the re-drying stage, temperature, relative humidity, and the temperatures in the first, second, and third drying zones had a higher impact on tobacco quality.

By analyzing the path of flame propagation in the flame-retardant test and the position of the filament deposition in the FDM process, six kinds of building directions that may affect the flame resistance performance are analyzed. These building directions are XY, XZ, ZX, YX-45, ZX-45, and XYZ-45. Specimens in these building directions were fabricated and tested according to the 60-second vertical Bunsen Burner test method in CCAR 25. The test results show that specimens with different building directions have various burn lengths. XY and YX-45 had the shortest burn length (best flame resistance performance). On the contrary, XYZ-45 had the longest burn length. The results also show that ULTEM 9085 sheets of 0.8mm thickness in all building directions could pass the civil aviation fire retardant tests.

The primary task of establishing an intelligent energy network is to achieve the intelligent measurement of energy sources such as water, electricity, and natural gas, etc. Among them, significant progress has been made in the intelligent measurement of electricity and water, but the intelligent measurement of natural gas is still an urgent technical problem to be solved. At present, the actually used gas flow meters in the market are still traditional mechanical gas meters, which require manually recording gas meter data in each household. The data cannot be connected to the internet and cannot collect instantaneous flow values in real time, which is not conducive to real-time peak shaving of the energy network and compatibility with national intelligent energy network projects. The MEMS gas flow sensor studied in this article has the advantages of small size, light weight, low power consumption, high reliability, high sensitivity, and easy integration, which is a highly promising technical means to solve the intelligent measurement of natural gas.

Taking the ejector rod of a series of long bolts on cold heading process as the research object, the force of ejector rod is simulated and analyzed by DEFORM-3D software in order to solve the problem of ejector rod fracture encountered with actual production. The buckling of ejector rod is analyzed by Workbench software, and the relationship between the stress of M6 outer hexagon longs bolt ejector rod with different length-diameter ratios of cold heading and the critical stress of destabilization is analyzed. The critical length-diameter ratio of the ejector rod to break with unprotected condition is obtained, which agrees with the production experience of an enterprise. The finite element analysis technology provides theoretical basis of the production of long bolts and provides standard for the design of cold heading ejection mechanism.

In this paper, three types of comparative tests are set up to analyze the differences and causes of temperature rise test methods measured by the temperature rise test methods in GB 16410-2020 Domestic gas cooking appliances and GB 16410-2007 Domestic gas cooking appliances. The results show that the material of the pot and the initial water volume of the test have relatively little influence on the temperature rise of the stove parts, and the temperature rise results of each component after heat equilibrium are close. The test results of GB 16410-2020 compared to GB 16410-2007, the temperature rise of the internal parts of the cooker is significantly increased, and the temperature rise value of the operating knob on the surface of the cooker is reduced. The GB 16410-2020 test method has led to an increase in the severity level of temperature rise performance.

Shipping labels are an important component of logistics. It includes all the vital information to have packages successfully delivered. During the packaging and delivery processes, the shipping labels can be damaged, which poses a challenge to the effectiveness of the sorting machine. In this paper, a shipping label generation model based on VGG19 network is proposed. Our model first splits the images into shipping labels and then extracts the features of unreadable ones, finally different types of shipping labels applied such features are generated. To evaluate the performance of our model, we conduct experiments on the sorting machine using the generated 7,500 labels by the model. The results show that the generated labels can evaluate the sorting machine effectively, which demonstrates the encouraging performance of our model.

The manipulation of underwater bubble using the superwetting surface is crucial for industrial and scientific research. However, most of the superwetting surfaces are not able to achieve precise control for underwater bubble transportation. Here, a new method was proposed to construct a superaerophobic wedge pattern on superaerophilic wedge surface for precise underwater bubble transportation. The pattern was fabricated on the aluminum plate for underwater bubble transportation by the secondary laser etching and fluoroalkylsilane modification techniques. In this study, the wedge angle and the length of superaerophobic wedge pattern were investigated for the underwater bubble transportation on the superaerophilic wedge surface, and the results showed that the transportation distance of underwater bubbles could be precisely controlled by adjusting the wedge angle and the length of superhydrophobic wedge pattern.

An embedded real-time environmental noise monitoring device is designed for long-term monitoring of environmental noise and noise information processing. The STM32F407 is used as the processing core of the device. A microphone signal conditioning circuit is designed for signal amplification. The ADC embedded in the STM32 is used for signal acquisition. Simultaneously, a BeiDou GNSS module and a 5G module are integrated on the device, and these modules allow the device to upload noise location information, time information, and noise monitoring calculation results to a cloud server. The designed acquisition circuit's sensitivity is calibrated with a reference sound source. The findings of the tests indicate that the noise monitoring device that is designed has the capability to gather and analyze noise data in real-time while also satisfying the practical demands of environmental noise monitoring.

Besides the driven head, the rivet shank expansion is one key product characteristic of riveted joint. The paper studies accurate mathematical modeling of pneumatic percussive riveting based on impacting dynamics. The pneumatic percussive riveting hammer and rivet are modelled as the piston-striker-rivet impacting system. Based on the proposed pressure bar impacting model, the numerical model of the pneumatic percussive riveting is constructed in the ABAQUS. The rivet’s dynamic behavior under high strain rate and the percussive squeezing forces are studied intensively. A pneumatic percussive riveting platform is constructed to gather the percussive squeezing force during the course of pneumatic percussive riveting experiments. The riveted plates and the gathered percussive squeezing forces are considered to validate the proposed numerical model. The experimental results show that the proposed numerical model predicts the pneumatic percussive riveting well. The proposed impacting model successfully modelled the percussive riveting process of the pneumatic hammer.

Manual percussive riveting quality varies due to the different operations of the workers, which result from different training categories and processes. The paper proposed a squeezing force based percussive riveting training system to improve the recruits’ operation skills and the training efficiency. Force sensor is installed in the bucking bar to gather the squeezing force signal of the percussive riveting. The squeezing force signal of the expert technicians is used as the standard operation of the manual pneumatic percussive riveting. Quantitative indices are extracted from the squeezing force signals in order to provide the recruits with quantitative parameter for efficient training. Data-driven training categories based on the proposed training platform are developed to assure the operators maintain the qualified skills constantly. The squeezing force-based training system for pneumatic percussive riveting provides good platform for the recruits training. The proposed system can be used for high-skilled technicians training with good quality and efficiency.

With the accelerated process of deep integration of industrialization and informatization, industrial control networks gradually move from closed to open, and the traditional information security risks are gradually introduced into industrial control networks. Gradually introduced into the industrial control network, how to accurately and efficiently mine industrial control network security vulnerabilities has gradually become a research hotspot. In this paper, we compare and analyze the false detection rate of the black-box genetic algorithm-based power system network security vulnerability mining method and the fuzzing test-based industrial control network protocol vulnerability mining method. The fuzzing test-based vulnerability mining method for industrial control network protocols revolves around the fuzzing test technology for industrial control network protocols, and a prototype system for vulnerability mining for industrial control network protocols Fuzzing test is designed and implemented for the above problems. Based on the black-box genetic algorithm is an all-round perception of the power system network posture, the overall security posture of the power system network is derived, the black-box genetic algorithm is introduced for black-box fuzzing testing, the target function is selected and test parameters are generated, the optimized samples are transmitted to the fuzzing test module, and the abnormalities are recorded in real time through the log monitoring test system. The results show that the black-box genetic algorithm-based power system network security vulnerability mining method has a low false detection rate and high reliability.

In order to study the influence of different coated tools on the machining accuracy and tool life of the workpiece, the cutting process of uncoated tool, CBN coated tool, TiAlN/TiN composite coated tool, TiCN/Al2O3/TiN composite coated tool and TiN/Al2O3 composite coated tool cutting Y1Cr17 stainless steel was simulated using Abaqus finite element analysis software to obtain The parameters of stress, cutting force and cutting temperature of each coated tool under the same cutting parameters were obtained. The effect of changing cutting parameters and coating thickness on cutting force and cutting temperature was also analyzed. The simulation results show that the CBN coating can significantly reduce the cutting force and cutting temperature, improve the machining accuracy and tool life, which has important reference significance for further research on the subsequent machining process.

This study aims to gain a deeper understanding of the welding process of large structural components through welding thermal process simulation and microstructure performance analysis. By using computer simulation methods, the influence of different parameters on welding results was studied. The research results indicate that computer simulation methods can quickly and comprehensively compare the effects of various welding conditions on welding results, including material selection, environmental temperature, welding layer setting, and other factors, which has guiding significance for formulating welding processes. This study conducted in-depth research on the welding process of large structural components through computer simulation methods and analyzed the impact of different parameters on the welding results. The research results have important guiding significance for the development of welding processes. In the welding simulation process, algorithm control is crucial, so it is necessary to have a sufficient understanding of the physical model characteristics and the principles of simulation calculation methods to improve the accuracy and efficiency of the simulation.

With the gradual maturity of Telematics technology, vehicle-road collaboration technology has the initial capability of safe and reliable interaction between vehicles, people and platforms in the "cloud", "end" and "block". This paper analyzes the architecture of the cloud platform of intelligent networked vehicles, adopts a research method divided by modules, uses MySQL to establish a database linking multiple tables, embeds multiple table connections, gives full play to the role of the main body of data applications, and provides basic protection for the research of the "cloud platform".