Abstract: Structural crashworthiness plays a core role in vehicle safety design, mainly focusing on the maximum impact force that the body structure can withstand in collision accidents, and striving to maximize collision energy absorption to ensure that passengers have sufficient living space. The design of structural crashworthiness needs to consider the deformation mechanism and energy absorption characteristics of vehicles under different collision modes, and improve crashworthiness through material selection, structural optimization, and other means. In addition, the structural crashworthiness is closely connected to the passenger restraint system, which together constitute the key to the passive safety performance of the vehicle. In vehicle safety design, the improvement of structural crashworthiness can significantly enhance the vehicle's ability to protect passengers in collision accidents and reduce the risk of injury. Therefore, in-depth research on structural crashworthiness and the development of efficient crashworthiness structures are important directions for improving vehicle safety performance. Read More

Abstract: As the application background of fieldbus becomes more and more extensive, PROF I BUS contains multiple master stations, and a multi-master system with multiple slave stations emerges at the historic moment. This paper establishes a multi-master communication system model and uses simulation technology to study the relationship between the target token cycle time, token waiting time, and master site address value. Read More

Abstract: This article first introduces the basic concepts and principles of PROFIBUS technology, and then elaborates on its application status in the field of industrial automation from three aspects: manufacturing, process control, and drive technology, including its wide range of applications and advantages. Subsequently, the main challenges currently faced by PROFIBUS technology were analyzed, such as integration with emerging industrial Ethernet technologies, data security issues, and the complexity of system upgrades and maintenance. Finally, the article looks forward to the future development trends of PROFIBUS technology, including further integration with industrial Ethernet technology and the introduction of encryption algorithms to enhance data security. Overall, PROFIBUS is a mature fieldbus technology. Still crucial in the field of industrial automation. However, with the development of new technologies and changes in application requirements, its future development still faces many challenges and opportunities. Read More

Abstract: The 21st century has witnessed a rapid evolution in information technology, leading to significant transformations in the automotive industry. The focus has shifted from purely mechanical enhancements to the advent of a new generation of vehicles equipped with intelligent driving technology. These smart vehicles are capable of perceiving their surroundings and adapting to real-time conditions and traffic, enabling assisted or even fully autonomous driving. This advancement promises substantial improvements in safety, environmental sustainability, and comfort, enhancing the overall driving experience. This paper provides a comprehensive overview of the current state of autonomous vehicle technology, focusing on the fundamental principles of intelligent driving. It delves into three key areas: environmental perception, path planning, and the application of artificial intelligence in autonomous driving systems. Read More

Abstract: In the operation of new energy vehicles, the energy supply method is directly related to the range and stability of the vehicle, and wireless charging technology is becoming a hot spot in the industry because of its efficient and convenient characteristics. This paper will discuss the core technology of wireless charging in new energy vehicles, covering the related equipment construction, compensation network design, and the design of key components of wireless charging technology improvement in new energy vehicles. The article will analyse the detailed results of the actual operation of the system, aiming to provide theoretical support and practical guidance for the application of wireless charging technology in new energy vehicles, and at the same time promote the further development of the new energy vehicle industry. Read More

Abstract: Spherical friction pairs are widely used in mechanical equipment, and predicting the wear of spherical friction pairs can help evaluate and predict bearing life. At present, when using the finite element analysis method to calculate the wear of spherical friction pairs, it is still necessary to simulate under idealized conditions, and the limitations of calculation amount and time need to be considered. The accuracy of the prediction method is measured by experimental means to measure the wear amount, which can be characterized by measuring the mass, volume, or wear thickness of the material under grinding. Based on the wear test methods used and the characteristics of the tested materials, suitable wear characterization parameters and measurement methods can be selected. This article also analyzes the influence of friction pair materials and service conditions on the wear of spherical friction pairs. Finally, the article looks forward to the development trend of predicting the wear of spherical friction pairs. Read More

Abstract: The WorldFIP protocol is the third part of the European standard EN-50150. It is particularly suitable for use in distributed computer control systems. WorldFIP provides data transfer services for variable exchange, and in order to cope with the real-time requirements of the system during variable transfer, the WorldFIP protocol provides communication services based on periodic and non-periodic identification exchanges, in which periodic exchanges have the highest priority and are scheduled cyclically according to the bus scheduling table at runtime. execution at runtime according to the bus scheduling table. Therefore, when constructing the scheduling table, the respective schedulability can be determined at pre-run time. For acyclic variable exchanges, the situation is different as they have a lower priority level and perform variable exchanges according to a first-come-first-served strategy. In this paper, from the perspective of variable exchange, we study the communication mode of the WorldFIP protocol, the process of cyclic and acyclic variable exchange, introduce a method for constructing bus scheduling tables based on microcycles and macrocycles, and finally give specific examples to prove the rationality of this method. Read More

Abstract: The working speed of the U-shaped ironless permanent magnet linear synchronous motor is determined by the frequency and pole pitch. When the motor’s working speed is required to be constant, different combinations of frequency and pole pitch can be chosen. This article mainly discusses the influence of the pole pitch on the motor performance when other parameters are kept constant. First, the magnetic field of the motor permanent magnet is analyzed using the equivalent magnetizing current method to discuss the relationship between the pole pitch and the motor air gap magnetic field. Then, the finite element method is used to analyze the influence of the pole pitch on the motor air gap magnetic field, transverse edge effect, and electromagnetic thrust considering the saturation effect of the magnetic yoke. The research shows that under the conditions of constant motor basic structural parameters and speed, and the same amount of permanent magnet material, both the air gap magnetic density and the motor thrust line density have maximum values as the pole pitch changes. The research results have certain guiding significance for the design of this type of motor. Read More

Abstract: In the context of increasing device switching frequencies year by year, non-ideal factors such as dead-zone effects in inverters not only cause output waveform distortion, but also generate harmonics that make the interaction between inverters and power grids more complex. In order to accurately describe and analyze this phenomenon and establish a more practical grid-connected inverter model, this paper proposes and establishes a three-phase LCL grid-connected inverter harmonic state space model that considers dead-zone effects. By incorporating dead-zone effects into the modeling process, the system transfer function matrix is derived to quantify the harmonic interaction coefficient between the inverter and the power grid, and the influence mechanism of dead-zone effects on the harmonic interaction process at high switching frequencies is analyzed in depth. The necessity of considering dead-zone effects is illustrated through simulation, and the effectiveness and accuracy of the inverter HSS model considering the effects of dead-zone effects are verified through experiments. Read More

Abstract: Based on the research of lower limb exoskeleton robots and extensive literature review, combined with human anatomy and kinematics, a four-degree-of-freedom lower limb exoskeleton robot was designed, and its three-dimensional model was established using UG software. In the design of the exoskeleton robot, it is required to have a simple structure, zero sensitivity in response speed, and be easy to realize automatic control. The exoskeleton robot designed in this paper uses electric push rods as the driving elements, and the dimensions of each part of the robot are obtained from the national standard human body size table; based on the analysis of the human gait cycle, and using cubic polynomial interpolation to plan the spatial posture of each joint; Adams was used to simulate the movement of the exoskeleton robot, and the motion curves of each joint were obtained. Read More

Abstract: This paper examines the optimal conditions for the three-coil Wireless Power Transmission (WPT) system. Initially, an equivalent circuit model was developed Experiments were conducted to explore the impact of the repeating coil parameters and load resistance on the three-coil WPT system. We determined the optimal distance between the transmitting coil and the repeating resonator under various parameters of repeating coil turns, as well as different load resistance, to maximize the system's overall transmission efficiency. It indicates that in the three-coil WPT system, the optimal distance between the transmitting and repeating coils is directly proportional to the load resistance. Moreover, when the turns of the transmitting, repeating, and receiving coils are fixed at seven, the optimal distance changes slightly as the number of turns of the repeating coil increases, but changes significantly when the number of turns decreases. Additionally, when the change in load is constant, an increase in the radius of the repeating coil results in a greater change in the optimal distance. These findings provide important reference information for optimizing the efficiency of triple-coil WPT systems. Read More

Abstract: A comprehensive design method for large-span gantry beams, combining process techniques and structural optimization, is proposed to address significant deflection deformation issues caused by their own gravity and the gravity of front attachments. Selecting the beam section type, finite element static analysis is performed using ANSYS Workbench for both cast and welded gantry beams. The maximum static deformation values of the beams for both process schemes are compared to determine the process scheme for the large-span beam. Subsequently, multiple structural dimensions of the welded gantry beam are parameterized, and sensitivity analysis is conducted to determine the degree of influence of each parameter on the optimization objective. Parameters with relatively small effects on the corresponding objectives are eliminated. A response surface multi-objective genetic algorithm optimization based on Box-Behnken design experimental design method is employed to minimize deflection deformation and reduce weight. The response surface model is fitted with expressions, and variance and significance analyses are conducted to validate the model's reliability. The optimal Pareto solutions are determined based on the response surface model using a multi-objective genetic algorithm. A comparison between the beams before and after optimization shows a reduction of 0.052 in maximum static deformation of the welded beam, representing an 8.3% decrease. Additionally, the mass decreases by 1710 kg, indicating a 14.63% reduction, demonstrating significant optimization effects. Read More

Abstract: Taking the electromagnetic brake as the research object, a new structure of double-winding electromagnetic brake is proposed in view of the serious temperature rise phenomenon of traditional single-winding electromagnetic brake, the high requirement of insulation level and the obvious decrease of electromagnetic force. The equivalent magnetic circuit method is used to analyze and calculate the magnetic field, and the simulation model of the new brake is constructed, and the influence of different parameters on the braking characteristics of the double-winding electromagnetic brake is analyzed by the single-variable method, and the influence curves of each parameter on the electromagnetic force and response time are obtained. At the same time, the magnetic-thermal coupling analysis of the double-winding electromagnetic brake is carried out, and the results show that the total ampere-turns and power of the double-winding electromagnetic brake decreases by 15.3% in the same proportion, the rated electromagnetic force decreases by 22.9%, the release time grows by 23.7%, and the closure time is shortened by 14.6%. Read More

Abstract: At present, computer technology and finite element software analysis technology have been widely used in the stamping and forming process of aluminum alloy hood outer plate to predict the possible quality defects in the stamping process, and effectively improve the quality and production efficiency of parts. The stamping and forming of the outer plate of the automobile aluminum alloy hood is a highly nonlinear process, and its forming quality involves many forming factors, if the variable design is not reasonable, it may lead to quality defects such as wrinkles or cracks of the molded parts. Due to the relatively complex shape and structure of the aluminum alloy hood outer plate and its high requirements for the quality of forming, it is difficult to obtain the optimal process parameters in a short time if the finite element software simulation optimization is carried out manually. The machine learning algorithm is applied to the research on the stamping and forming of the outer plate of the aluminum alloy hood, and the multi-objective genetic algorithm is used to optimize the stamping process parameters of the covers, which can meet the maximum thinning rate of the formed parts and control the rebound of the formed parts to a certain extent. How to combine machine learning algorithms with finite element simulations to reasonably adjust the process parameters in the stamping and forming process by using machine learning algorithms to meet the forming quality requirements of aluminum alloy hood outer plate has always been a research hotspot and difficulty in the field of aluminum alloy hood outer plate stamping. Read More

Abstract: In response to the issue that particle swarm optimization algorithms tend to fall into local optima when dealing with multi-objective optimization tasks, a multi-objective optimization algorithm based on particle swarm is proposed. This algorithm is based on the relationship between the position vectors of particles, changing the selection and movement strategies of particles to find the true Pareto front. Firstly, two additional position vectors are added around the iterating particles to enhance their search capability; then, a non-dominated vector archive is established to record the non-dominated solutions of the iterating particles and the additional position vectors, increasing particle diversity. Finally, additional position vectors with high fitness are selected to produce a shift in the iterating particle's position, accelerating particle convergence. Comparing this algorithm with dMOPSO, SMPSO, NMPSO, and MOPSOCD algorithms, simulation experiments show that the proposed PVSPSO algorithm has stronger optimization ability. Read More