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There is a growing interest in the area of human – robot interactions as the human – robot interactions plays an important role in the control design for the robot. The paper proposes a feedback torque control for a three degree of freedom model of an arm exoskeleton used for assisting user movement. Base on controlling the interaction torques in three joints of the robot to track the desired interaction torques, the feedback torque control is carried out to shape the impedance of the device. The optimal feedback torque control is carried out to minimize the total root mean square of human – robot interaction torques at three joints by using the Balancing Composite Motion Optimization.

Brake system reliability is critical for the safety and performance of heavy vehicles, including semi-trailers, passenger buses, and industrial transport units. This study investigates the thermal fatigue failure mechanisms in brake discs (BDs), which are subjected to extreme operational conditions. The primary motivation is to enhance brake disc durability and reduce the risk of catastrophic failures by understanding the interplay between material properties, thermal stress, and fatigue resistance. A comprehensive experimental approach was employed, including visual inspections, chemical composition analysis, metallurgical structure examination, hardness testing, and tensile strength evaluation. The study compares brake discs that have undergone extensive service with those in an undamaged state to identify critical degradation patterns. The results indicate that temperature fluctuations and cyclic thermal stresses induce crack formation and propagation, with rough graphite inclusions significantly reducing fatigue strength. Furthermore, deviations in silicon and carbon content were found to impact material integrity, contributing to premature failure. The findings of this research provide actionable insights for optimizing brake disc design, material composition, and manufacturing processes. By modifying graphite distribution, refining alloy compositions, and improving thermal resistance, future brake systems can achieve greater durability and reliability. These advancements will directly enhance braking efficiency, reduce maintenance costs, and improve overall vehicle safety.

Delta robots play a critical role in high-speed industrial applications due to their parallel kinematic structure, which provides superior precision, agility, and efficiency. This study presents a reconfigurable Delta robot with a novel structural adaptation mechanism, allowing geometric modifications to optimize its kinematic and dynamic performance. The research systematically derives the robot’s kinematic and dynamic equations, examines the impact of altering the structure of its chains, and applies genetic algorithm optimization to enhance its overall functionality. The influence of varying arm lengths, chain structures, and joint configurations is analyzed to determine their effects on workspace, actuator torque requirements, and operational stability. The findings indicate that optimized chain configurations improve workspace utilization by up to 15 %, reduce actuator torque by 12 %, and enhance end-effector speed by 8 %. By integrating structural adaptability and optimization techniques, this study demonstrates that the reconfigurable Delta robot achieves a superior balance between precision, speed, and energy efficiency. These advancements make it a promising solution for next-generation high-speed robotic applications in industries such as packaging, assembly, and medical automation.

The study aims to develop a model for optimizing the concentration of solution parameters in the dyeing process of polyacrylic yarns. Specifically, the study examines the use of cationic retaiders and acetic acid, which affect the wavelength as an indicator of yarn color aging. By optimizing these parameters, the objective is to improve the color stability and longevity of dyed polyacrylic yarns. The application of Response Surface Methodology (RSM) encompassed two distinct types of data distribution properties: linear and non-linear. The R-squared (R2) value for the non-linear RSM model was 0.96, compared to 0.86 for the linear RSM model. These results indicate that the model formed based on the non-linear RSM offers superior predictive ability in optimizing solution concentration as a parameter in the polyacrylic yarn dyeing process compared to the linear RSM-based model. In addition to providing practical implications for textile practitioners, this study contributes theoretically by emphasizing the effectiveness of statistical methods such as RSM in manufacturing process analysis.

Through field measurement, numerical simulation and theoretical analysis, the influence of shield tunnel construction on the deformation of ceramic soil layer strip foundation is discussed. A three-dimensional numerical model of strip foundation in ceramic soil layer is established, and the effects of different shield types and parameters on the longitudinal deformation of strip foundation are analyzed using Timoshenko beam model. The increase of thrust of shield, torque of cutter head and speed of driving led to an increase of about 25 %, 28 % and 32 %, respectively, while the decrease of pressure of synchronous grouting and pressure of shield opening also aggravated the settlement. The study quantified the leading role of pressure of shield opening for the first time, revealed the double-sided effect of excavation pressure, and proposed a multi-parameter collaborative optimization strategy.

In order to explore the impact of near surface ore body mining on the stability of overburden and surface dangerous rock masses, a Phosphate Mine was used as the engineering background. On-site investigation method was adopted to clarify the stability conditions of the surface dangerous rock. Numerical analysis software was used to simulate the evolution laws of overburden deformation, stress, and plastic zone. The research results indicate that the development of interlayer structural planes in the surrounding rock of the roof of the mining area can easily cause the collapse of the roof slab or sheet. The strata are hard and brittle in lithology, with developed rock fractures. Dangerous rock blocks are formed under the combination of fissures and rock layers. The mining disturbance generated during the mining process is relatively small. The impact on the rock layers, adjacent mining sites, and surface stability is weak. The surface is less affected by the mining of underground ore bodies and has not reached the maximum allowable value. Under the condition of first mining the ph1# ore body and then mining the ph2# ore body, the displacement of the overburden is relatively small. There is no distribution of connectivity in the plastic zone in the mining pillars, mining areas, and overburden. The research results can provide theoretical reference for the feasibility analysis of near surface ore body mining in similar mines.

As energy demand continues to grow and environmental issues become more severe, the development and utilization of clean energy natural gas are becoming increasingly important. This paper focuses on the impact mechanism of landslide disasters on pipelines, analyzing how landslide displacement, width, pipeline wall thickness, and internal pressure affect pipeline stress and displacement. The study finds that landslides cause stress concentration at the middle and boundary positions of pipelines. As landslide displacement increases, pipeline stress also increases. For example, when landslide displacement is 1.2 meters, pipeline stress is approximately doubled compared to when the displacement is 0.6 meters. This research aims to explore the impact mechanism of landslide disasters on the stress response of natural gas X80 pipelines, with the goal of providing technical support for their stability and reliability.

During the development of a hatchback car, a problem of ear-pressing noise caused by low-frequency road noise was encountered. Through the analysis of the vehicle’s transmission path, the mechanism of the problem, and experimental verification, it was confirmed that the low-frequency road noise problem inside the car was mainly caused by the road exciting the tire, transmitted through the suspension system to the subframe, arms, and other bottom plate components, and then transmitted to the body, causing the rear door bending mode to be excited and generate resonance, the body panel deformation squeezing the interior cavity, causing air pressure fluctuations in the car, and ultimately causing the low-frequency road noise ear-pressing problem. To solve the low-frequency road noise problem during vehicle operation, this paper studied the noise optimization scheme for the hatchback rear door, proposed a low-frequency road noise control solution, and successfully solved the low-frequency road noise problem of the hatchback car through in-vehicle verification, proving the effectiveness of the low-frequency road noise control solution and improving the driving comfort of the car, providing important guidance for NVH low-frequency road noise control.