Modeling and Simulation Analysis of Intelligent Vehicle Operating Safety State on Icy and Snowy Roads Based on Car‐Following Theory

ABSTRACT To address the issue of determining and quantifying the safety level of vehicle following on icy and snow‐covered roads in cold regions, this study focuses on intelligent vehicles operating in such environments and aims to identify their safety states. Initially, key indicators for determining the safety state of intelligent vehicles are identified by analyzing the vehicle‐following operational conditions on icy and snow‐covered roads. Subsequently, a safety state identification model for intelligent vehicle operation in following scenarios on icy roads is constructed based on these indicators. Finally, a simulation scenario model is developed using the co‐simulation platform of CarSim and Simulink to perform simulation analysis and validation of the proposed safety state identification model. The results demonstrate that the constructed model integrates three key indicators: Time‐to‐Collision (TTC), Time‐to‐Stop (TTS), and Time Headway (TH). To unify the evaluation of different indicators, a dimensionless parameter termed the safety degree is introduced, which synthesizes the influence of TTC, TTS, and TH into a single criterion for distinguishing safe states from hazardous ones. The following safety degree of vehicles increases with the increase of TTC and TH and decreases with the increase of TTS. During vehicle‐following operations, the safety degree decreases from 1 to 0.3 when the leading vehicle decelerates, indicating a risky operational state, while it increases gradually when the leading vehicle accelerates. After 11 s, the leading vehicle's speed exceeds its initial value, and the safety degree of the following vehicle rises almost linearly, reflecting an improvement in the evaluated safety state. These results confirm that the proposed model satisfies the requirements for judging and predicting the operational safety state of intelligent vehicles in following scenarios on icy and snowy roads, and it provides theoretical support for the safety assessment of intelligent driving under complex low‐adhesion conditions.

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End‐to‐End Design and Validation of a Low‐Cost Stewart Platform With Nonlinear Estimation and Control

ABSTRACT This paper presents the complete design, control, and experimental validation of a low‐cost Stewart platform prototype developed as an affordable yet capable robotic testbed for research and education. The platform combines off‐the‐shelf components with 3D‐printed and custom‐fabricated parts to deliver full six degrees‐of‐freedom (6‐DoF) motions using six linear actuators connecting a moving platform to a fixed base. The system software integrates dynamic modeling, data acquisition, and real‐time control within a unified framework. A robust trajectory tracking controller based on feedback linearization, augmented with an LQR scheme, compensates for the platform's nonlinear dynamics to achieve precise motion control. In parallel, an Extended Kalman Filter fuses IMU and actuator encoder feedback to provide accurate and reliable state estimation under sensor noise and external disturbances. Unlike prior efforts that emphasize only isolated aspects such as modeling or control, this work delivers a complete hardware–software platform validated through both simulation and experiments on static and dynamic trajectories. Results demonstrate effective trajectory tracking and real‐time state estimation, highlighting the platform's potential as a cost‐effective and versatile tool for advanced research and educational applications.

Design and Optimization of PID Controller for Renewable Energy Integrated Power System Using Model Order Reduction

ABSTRACT This article presents the design of a proportional‐integral‐derivative (PID) controller for a renewable energy (RE) integrated power system using model order reduction (MOR). A test case of an 11th‐order RE‐integrated power system from the literature has been used to validate the applied method. The reduction of the 11th‐order Renewable Energy (RE) integrated power system model to a 2nd‐order model is achieved using a combination of Pade approximation (PA) and direct truncation (DT) (PA‐DT) method. Further, the grey wolf optimization (GWO) technique is employed to determine the optimal parameters for the PID controller for the reduced‐order model. The designed controller is then directly applied to the high‐order system (HOS). This proposed PID design method via PA‐DT MOR for the RE integrated power system is a novel technique because, at this stage, no publications related to this combined method are available. The suggested approach is supported by the time and frequency responses. Time domain specifications (TDSs) and performance error indices (PEIs), and statistical analysis are also provided to demonstrate the efficacy of the suggested method.

Fabrication of Metallic Products Using Digital Light Processing‐Based Additive Manufacturing: A Review

Direct 3D printing of green bodies and indirect 3D printing for assisting a casting process represent two promising applications of additive manufacturing (AM) based on digital light processing (DLP) for creating high‐precision metallic components. Since direct 3D printing is still limited to specific materials, like copper and stainless steel, there is a need to expand this technology to other alloys. The ability to scale it up is further hampered by issues in preprocessing, printing, and post‐treatment. This review discusses the complete process chain and applications of DLP in detail. Subsequently, some challenges, such as scattering and residual char, are identified as the remaining obstacles in the current DLP technology. To increase DLP's applicability to high‐value industries, a summary of solutions, like preparation of refractive index‐tuned slurries, a method to assist in finding printing parameters, and using nanosize powders in mixed slurries, is elucidated. Details of the future research directions pertaining to the method for utilizing carbon‐free photopolymer binder, multistage debinding‐sintering cycles, and incorporating machine‐learning‐assisted real‐time monitoring to achieve defect‐free, industrial‐scale production are mentioned. This work provides a template to fully realize DLP‐AM's potential as a flexible, effective platform for advanced casting workflows and various metallic material fabrication.

Low‐Temperature Superplastic Forming of High‐Entropy Oxides

High‐entropy oxides (HEOs) are being extensively studied for various functional applications, but there is limited research into the mechanical behavior of these materials, especially at elevated temperatures. Bulk (Co, Cu, Mg, Ni, Zn)O (transition metal (TM)‐HEO) samples are formed into dome shapes at 800 °C and 70 kPa. Deformation experiments and finite element analysis (FEA) reveal that TM‐HEO has a creep stress exponent of n  = 0.6, indicating that TM‐HEO deforms through superplastic deformation and exhibits shear‐thickening behavior. Comparisons of experimental strain rates to those calculated using existing superplasticity mechanism models signify that TM‐HEO deforms through grain boundary sliding accommodated by a solution‐precipitation mechanism from a secondary phase. A Cu‐rich tenorite phase, commonly observed in the grain boundaries of TM‐HEO, is proposed as the secondary phase facilitating deformation. It is important to highlight here that the superplastic deformation behavior in TM‐HEO is active under modest temperature and pressure conditions, as noted above. Low‐temperature superplastic deformation will provide a powerful method of manufacturing HEO ceramics into net shape parts, greatly expanding their potential applications.

Electrospark‐Deposited AlCrFeCoNi High‐Entropy Alloy Coatings on Steel: Microstructure Evolution, Mechanical Properties, and Corrosion Response

Recent advancements in high entropy alloys have garnered considerable attention due to their exceptional properties, especially for applications in extreme environments, where coating materials are critical to performance and cost‐effectiveness. This study investigates the microstructure, mechanical properties, and corrosion behavior of AlCrFeCoNi high entropy alloys (HEA) coatings deposited on medium carbon steel using electrospark deposition. The as‐deposited coatings exhibit a body‐centered cubic phase with cellular grains and a uniform elemental distribution. Postdeposition heat treatment induces elemental diffusion, leading to phase segregation, elemental clustering, and a noticeable reduction in microhardness from 730 to 540 HV, and yield strength from 1036 to 761 MPa. Both as‐deposited and heat‐treated coatings demonstrate enhanced corrosion resistance, with the latter showing corrosion rates in both NaCl solution of 5.31 μA cm −2 lower, and acidic environments of 6.17 μA cm −2 lower. These findings highlight the potential of AlCrFeCoNi HEA coatings for extending the service life of components operating under harsh conditions.

Compression Behavior of M2052 Alloy Lattice Structures Fabricated by Selective Laser Melting

The M2052 alloy (Mn‐20Cu‐5Ni‐2Fe at%) exhibits excellent damping capacity and favorable mechanical strength, making it a promising candidate for vibration damping and energy absorption. However, its potential in lattice structures has not been reported to date. In this article, M2052 alloy lattice structures are fabricated via selective laser melting to evaluate their mechanical properties and energy absorption capabilities. Three lattice architectures with comparable relative densities are designed and manufactured: body‐centered cubic (BCC), BCC with vertical struts (BCCZ), and reinforced hollow BCCZ (RHBCCZ) featuring hollow struts and strengthening ribs. Quasi‐static compression tests and finite element simulations are conducted to analyze their mechanical responses and deformation mechanisms. Furthermore, the effects of heat treatment on the compressive properties and microstructural evolution of BCC lattices are investigated. Results demonstrate that the RHBCCZ structure delivers optimal performance, with a Young's modulus of 1506.3 MPa, yield strength of 18.41 MPa, and maximum energy absorption of 22.69 J cm −3 . Heat treatment enhanced the yield strength and altered the deformation mode of the lattice. This article highlights the potential of M2052 alloy in load‐bearing, energy‐absorbing, and lightweight structural applications.

Scalable Robotic Laser Texturing of Tilted Microanchors for Direction‐Independent Metal–Polymer Joining

As the mobility sector advances toward battery‐powered transportation, the demand for lightweight structural components with high mechanical integrity continues to grow. Metal–polymer hybrid structures offer a promising solution; however, direct joining between dissimilar materials often results in weak interfacial anchoring, necessitating additional fasteners or adhesives. This study presents a robot‐assisted laser texturing technique for fabricating high‐aspect‐ratio, surface‐tilted, recast‐based microstructures that enhance the strength of metal–polymer joints. A six‐axis robotic system enables precise control of the laser incidence angle, interline pitch, and scanning path, promoting recast layer overlap while minimizing thermal distortion through an anomalous scanning strategy. The method supports scalable fabrication of various microstructural patterns, including groove, circular, and wobble geometries. Tensile tests demonstrate strength improvements of up to 13.41× for groove structures and 14.11× for wobble structures, the latter providing direction‐independent interlocking. These results highlight the potential of this approach for robust, adhesive‐free integration of metal–polymer hybrids in lightweight mobility applications.

Femtosecond Laser Fabrication of Biomimetic Super‐Slippery Surfaces: A Review

The biomimetic super‐slippery surface is a solid–liquid composite structure formed by infusing a low‐surface‐energy lubricant into micro‐ and nanostructured substrates. Owing to its outstanding liquid‐repellent and self‐healing capabilities, this surface holds substantial research significance and broad application potential. Femtosecond lasers, owing to their broad material compatibility, high processing precision, and excellent controllability, are considered an effective technique for the fabrication of super‐slippery surfaces. The article begins by summarizing the characteristics, fabrication principles, and current state of research on super‐slippery surfaces. It then emphasizes femtosecond laser‐based fabrication, discussing the corresponding mechanism and advantages, as well as recent advances in preparing super‐slippery surfaces on diverse substrates such as polymers, ceramics, metals, and alloys. The article also discusses the diverse applications of super‐slippery surfaces fabricated via femtosecond laser processing, including corrosion resistance, anti‐icing, antifouling, emerging fields such as biomedical engineering, blood compatibility, and controlled droplet transport. Finally, this work summarizes the key issues and challenges that remain in the femtosecond laser fabrication of super‐slippery surfaces.