Browse Topic: Lasers

Items (2,265)
Find
Microstructure and Mechanical Properties of Vacuum Laser Welded Joints in 42CrMo Thick Plate2026-99-01327/31/2026
Vacuum laser welding trials were carried out on 42CrMo steel, a material widely utilized in the defense sector. By employing a 30 kW fiber laser system, complete penetration welds were successfully produced on 20 mm thick 42CrMo steel plates. The resulting joints displayed satisfactory surface quality on both the top and bottom sides, with no evident defects such as cracks or porosity. A comprehensive analysis of the joint microstructure and mechanical properties was conducted. Findings reveal that the weld zone (WZ) is predominantly composed of lath martensite, accompanied by minor quantities of plate martensite, organized as columnar crystals. The joints demonstrated high tensile strength at ambient temperature, with fracture consistently occurring within the base metal (BM). Microhardness measurements indicated higher values within the weld relative to the base metal, and no pronounced softening was detected in the heat-affected zone (HAZ). Additionally, the joints exhibited commendable impact toughness, suggesting overall superior mechanical performance.
Shi, Haicheng, Zhang, Guoyu, Li, Wuhong, Cao, Dongxu, Liu, Tianlei
Micro-Groove Fabrication and Simulation Analysis on PEEK Surface under UV Nanosecond Laser Irradiation2026-99-02257/31/2026
This study investigates the interaction mechanism between ultraviolet nanosecond pulsed lasers and polyetheretherketone (PEEK). By integrating finite element simulations with experimental validation, the work explores the laser microtexturing characteristics of PEEK surfaces and evaluates the influence of microtextures on the material’s surface biocompatibility. First, the interaction between the laser and the PEEK polymer was analyzed, and a laser ablation model was established using the COMSOL Multiphysics simulation platform. Using finite element simulation, the effects of spot overlap ratio were investigated by adjusting the average laser power, while the influence of single-pulse energy on the ablation characteristics of the PEEK surface was examined by varying the scanning speed. Subsequently, ultraviolet nanosecond laser processing experiments were conducted on planar PEEK microtextures based on the simulation results. Taking surface microgrooves on PEEK as representative structures, the variations in groove depth and width under different combinations of laser parameters were analyzed. The parameters, including average laser power, scanning speed, and repetition frequency, were optimized to identify processing conditions that yield stable depth and width, along with good surface flatness. Finally, experiments have initially verified that the microtextured PEEK surface may improve biocompatibility and regulate surface wettability to a certain extent.
Wu, Yifan, Wang, Xiaohui, Han, Yujie, Jin, Shuo
Design and Optimization of Hollow Rotating Traveling Wave Ultrasonic Motor Based on Laser Beam Expander2026-99-01547/31/2026
To meet the critical need for rapid response and miniaturization in laser beam expander drive systems, this study proposes an innovative actuation solution based on a hollow rotary traveling-wave ultrasonic motor. By thoroughly analyzing the optical adjustment mechanism of laser beam expanders and the electromechanical coupling behavior of ultrasonic motors, the motor structure was systematically optimized. Using a multiphysics coupling approach, the performance of stators fabricated from three distinct materials was compared, and parametric optimization was conducted. Experimental verification confirms that the developed ultrasonic motor precisely matches the load characteristics of beam-expanding optics while fulfilling the stringent requirements for both fast response and compact design. This research provides a reference for the miniaturization drive of high-precision optical systems, with promising applications in space optics and precision instrumentation.
Qiu, Haihui, Niu, Chuanhu, Xiao, Zhong, Xu, Zhangfan, Li, Jialiang, Pan, Song
A Stress Relief Method Based on a Hybrid Process of Shot Peening and Laser Directed Energy Deposition with the Same Materials2026-99-02327/31/2026
Laser directed energy deposition (LDED) is widely used in various fields due to its fine forming structure and superior performance. However, the characteristics of the hot forming process result in significant residual tensile stress in the formed materials, which affects the capability and useful life of the mechanism accessory. The hybrid manufacturing technology of shot peening (SP) and LDED has a significant influence on the elimination of defects and the improvement in microstructure of formed materials and reducing residual stress, but it also has limitations. To solve the problems, such as the introduction of powders and the difficulty in recycling and classification when using heterogeneous materials for shot peening in hybrid processes, this paper proposes a method of strengthening with the same material, establishes a thermal shot peening simulation model for the hybrid process, and conducts experimental verification. The research finds that the average generated stress of SP in hybrid manufacturing technology is -215.6 MPa, and the thickness of the strengthening layer is about 40 μm. The subsequent hot forming process will eliminate part of the induced stress by SP on the previous deposition, but the deposited stress on the surface is reduced compared with that in the single process. The hybrid manufacturing technology of SP and LDED, based on the same material, effectively utilizes the residual heat from the forming process, providing feasibility for engineering applications.
Zhang, Xiaoyu, Zhang, Min, Li, Dichen, Jiang, Yunfeng, Chen, Xinjin, Fei, Ya, Hu, Ying, Liu, Yuyang
Research on Welding Deformation of the Car Body Based on 3D Laser Scanning2026-99-08217/30/2026
This study aims to verify the accuracy and stability of a system used for measuring and analyzing the welding deformation of vehicle bodies under different welding parameters. A 3D laser scanner was employed to capture the surface topography data of the vehicle’s front deck before and after welding. In order to determine the welding deformation, PolyWorks software was utilized for deformation analysis, which processed the 3D scanning data and compared the post-welding data set. A dedicated vehicle body welding deformation measurement system was developed, including hardware configuration and software development. The BP neural network algorithm was adopted to predict the welding deformation, and the results indicated that the deviation between the predicted values and the average experimental measurements was less than 10%. This confirmed the practicality of the BP neural network in predicting welding deformation and highlighted its effectiveness in technical support for the optimization of welding parameters and deformation control in automotive manufacturing.
Li, Lina, Zhang, Yiqi, Sun, Hongchang, Wei, Xiezhen
Three-Dimensional Transient Thermal-Fluid Coupling Numerical Simulation of the Molten Pool in Aluminum Alloy Laser Welding2026-99-08547/30/2026
Laser welding technology for aluminum alloy electrode and busbar connections: addressing challenges in battery module assembly. In this work, a CFD framework was built in ANSYS Fluent using a Gaussian rotating heat-source representation, while a VOF approach was used to capture the transient gas–liquid interface in deep-penetration welding. A three-dimensional, transient, thermal-fluid coupled numerical model of the dual-layer heterogeneous aluminum alloy laser deep penetration weld pool was established concurrently with laser deep penetration welding experiments. Results indicate: Peak flow velocities in the weld pool during welding are concentrated along the weld centerline, with flow vectors predominantly directed axially along the weld. Once a quasi-steady keyhole regime is established, vaporization-induced recoil pressure becomes the primary driver governing melt circulation. The liquid metal first impinges on the pool bottom along the keyhole wall and then recirculates upward near the pool boundary, producing strong vortical motion. These findings are intended to support parameter selection and process optimization for laser welding of layered dissimilar aluminum components used in battery tab–busbar assemblies.
Lv, Wenjun, Wu, Yan
Experimental Validation of Frame-Dependent Gyroscopic Frequency Splitting in a Freely Rotating Tire Using Wireless MEMS Accelerometers and Scanning Laser Doppler Vibrometer2026-01-07006/20/2026
Gyroscopic effects split circumferential traveling-wave resonances of rotating structures into forward and backward branches. This work first analyzes the splitting in the co-rotating (Lagrangian) frame to provide physical intuition for the evolution of the two branches with spin speed. A transformation to the inertial (Eulerian) frame is then derived, showing that the observed frequencies are shifted by a kinematic Doppler-like term that acts with opposite sign on the forward and backward waves, leading to different Campbell-diagram slopes depending on the observation frame. The resulting framework is validated experimentally on a freely rotating, unloaded tire using two complementary sensing modalities: wireless on-tire accelerometers (co-rotating view) and a scanning laser Doppler vibrometer (inertial view). A frequency-domain SVD-based identification (FDD/ODS-SVD) is used to extract poles and deformation patterns over a range of spin speeds, enabling Campbell diagrams in both frames. The application of the proposed transformation maps the co-rotating branches onto the inertial observations, yielding consistent forward/backward splitting between the two measurement systems.
del Fresno Zarza, Javier, Naets, Frank
Control Measures for Laser Safety in the Navigable AirspaceARP5572B (Current)6/15/2026
This SAE Aerospace Recommended Practice (ARP) provides information and guidance for the control of hazardous laser exposure in the navigable airspace. This ARP does not address techniques that pilots can apply to mitigate laser illuminations during a critical phase of flight. Such mitigation strategies are described in ARP6378.
G-10T Laser Safety Hazards Committee
Safety Considerations for Lasers Projected in the Navigable AirspaceARP5293B (Current)6/15/2026
This document applies to laser proponents involved with the use of laser systems outdoors. It may be used in conjunction with AS4970, ARP5535, ARP5572, and the ANSI Z136 series of laser safety standards.
G-10T Laser Safety Hazards Committee
Zero-Shot Classification of Additive Manufacturing Anomalies2026-26-07216/1/2026
Additive Manufacturing (AM) process involves building part layer by layer. Some of the AM processes ( Laser and Electron beam based) generate a melt pool during printing process. This melt pool can be captured periodically during AM process using special optical arrangements. These images capture high intensity melted zone, heat affected zone, splattered molten metal particles and overall shape of the melt pool. These images carry similar characteristics for good AM processes within a range. When there is an anomaly the above said characteristics of the melt pool changes, for example a low intensity melted zone signifies low energy condition which can lead to defects like balling etc. Hence the captured image at this condition appears significantly different from other images. The common defects which can be detected by analyzing melt pool images are porosity, spatter, lack of fusion, cracks, balling and keyhole instability. There are many machine learning methods available to quantify this (supervised and unsupervised). The proposed approach does not require a trained machine learning (ML) model from scratch but rather utilize a pretrained self-supervised vision transformer (ViT) model DINO v2. The melt pool images acquired during the additive manufacturing (AM) process are processed by DINO v2 ViT model. These future vectors or embeddings for all printing instances are extracted and stored for downstream processing. Zero shot classification (accept or reject) of an AM printing instance is done by comparing the production printing instance image with a baseline printing instance image at the same spatial coordinates using Euclidean distance metric. This baseline Euclidean distance metric is established from multiple printed instances of the baseline coupons and by calculating root mean square deviation (RMSD) at each spatial coordinate of the print instances. The deviations of the production print instances are calculated by calculating RMSD of the Euclidean distances of embeddings of the melt pool images with that of baseline image embeddings at the same spatial coordinates. The deviations observed can be correlated to actual defects by analyzing AM printed parts layer by layer at each spatial coordinates using destructive or non-destructive testing techniques. The scope of this paper is only on establishing the deviation calculation methodology.
Kuppusamy, Balasundar
Design of a Modular High-Power High-Repetition-Rate Semiconductor Pulsed Laser Power Supply2026-99-07165/15/2026
Pulsed lasers serve as critical components across a diverse spectrum of modern applications, ranging from precision manufacturing and medical equipment to advanced defense systems. Their performance is fundamentally governed by the pulsed power supplies that act as their energy source, where output characteristics such as stability, rise time, and efficiency directly dictate the quality and reliability of the laser output. Aligned with the prevailing industrial trend towards miniaturization and digital control in semiconductor laser pump drivers, this paper introduces a high-power, high-repetition-frequency pulsed laser power supply. The proposed design is architect ed around a phase-shifted full-bridge charging network for efficient energy transfer and a modular, switched-mode constant-current pulsed discharge network for precise output shaping. This integrated architecture provides versatile and independent control over key output parameters, including current amplitude, pulse width, and repetition frequency, offering significant flexibility for various operational requirements. The adopted switched-mode constant-current driving technique presents a substantial advantage over conventional linear constant-current methods. It drastically reduces conduction losses inherent in linear regulators, which is a decisive factor for enhancing overall system efficiency, particularly in demanding long-pulse application scenarios where thermal management is challenging. This work comprehensively details the systematic modeling, in-depth analysis, and tailored control design undertaken for both the front-end charging network and the rear-end pulse-forming modules. To validate the design methodology and practical performance, a functional prototype was developed and subjected to rigorous testing. Experimental results confirm that the prototype achieves a maximum constant-current pulsed output of 400 A, featuring a remarkably fast rise time of less than 10 μs. Furthermore, it demonstrates a wide range of operable pulse widths up to 1000 μs and sustains a maximum repetition frequency of 1000 Hz, thereby meeting the stringent demands of advanced high-power pulsed laser systems.
Huang, De, Lu, Jiawei, Yang, Zhiqing, Xv, Ziyi, Xing, Hui
A Comparison between Leica RTC360 and Recon-3D Scan Data in Pre- and Post-Collision Vehicle Documentation2026-01-50304/22/2026
Documenting and mapping using three-dimensional (3D) technologies have become essential in crime- and crash-scene investigations in recent years. Traditionally, this has been accomplished using terrestrial laser scanners (TLS), which often come with significant upfront costs. In contrast, Recon-3D, launched in 2022, leverages the capabilities of Apple’s light detection and ranging (LiDAR) sensor, available in Pro and Pro Max models since 2020. This study aims to evaluate the relative accuracy of documenting vehicles in both pre- and post-collision conditions using these technologies. A deviation analysis was conducted utilizing CloudCompare software to compare point cloud data collected from the Leica RTC360 laser scanner with that obtained from Recon-3D for 7 vehicles in a pre- and post-impact condition for a total of n = 14 vehicles. At the 1, 2, and 3 cm deviation thresholds, the average percent of points which fell below each threshold level for all vehicles was 66%, 91%, and 97%, respectively. Overall, the results indicate that Recon-3D delivers point cloud data that is useful for pre- and post-collision vehicle documentation.
Lim, Jihwa, Liscio, Eugene
Enhancing LiDAR Performance under Fog with Adaptive Multi-Echo and Feature-Based Filtering2026-01-00114/7/2026
LiDAR (Light Detection and Ranging) systems are essential for autonomous driving (AD) and advanced driver-assistance systems (ADAS), providing accurate 3D perception of the surrounding environment. However, their performance significantly deteriorates under adverse weather conditions such as fog, where laser pulses are scattered by airborne particles, resulting in substantial noise and reduced ranging accuracy. This scattering effect makes it difficult to detect objects within or behind particulate matter, posing a serious challenge for reliable perception in real-world driving scenarios. To address this issue, we propose an algorithm that combines adaptive multi-echo signal processing with a feature-integrated, rule-based denoising framework to enhance LiDAR performance in noisy environments. The multi-echo approach selectively utilizes meaningful signal returns by evaluating both intensity and relative echo positions. Based on predefined rules, the algorithm identifies the echo most likely to represent a real object. The rule-based denoising algorithm dynamically adjusts thresholds by integrating multiple features, including point clouds density, intensity, and echo width. These features are evaluated in conjunction with measured distance to adaptively suppress fog noise and improve signal reliability. This synergistic method enables robust detection of real objects even in low-visibility conditions. Experimental evaluations demonstrate that the proposed algorithm significantly improves effective ranging distance under adverse conditions compared to conventional methods. Furthermore, it eliminates up to approximately 99% of noise induced by airborne particles in foggy scenarios. These results highlight the potential of our approach to enhance LiDAR reliability and safety in real-world automotive applications, contributing to the advancement of autonomous driving technologies under all-weather conditions.
Kaito, Seiya, Zheng, Shengchao, Fujioka, Ibuki, Beppu, Taro
Development of Technology to Distinguish Contaminants using LiDAR Near-Field Point Cloud based on Real-Field Data2026-01-00204/7/2026
Reliable environmental perception under adverse and contaminated conditions is a critical requirement for autonomous driving systems. Although LiDAR sensors play a central role in such perception, their performance is significantly degraded by surface contamination caused by environmental factors such as rain, snow, dust, anti-icing materials, and bug splatter impacts. However, most existing public datasets and prior studies rely on simulated or laboratory-generated contamination scenarios, which limit their applicability to real-world autonomous driving. To address this gap, we construct a large-scale real-world dataset collected from approximately 22,000 km of on-road driving across diverse regions of the United States, covering a wide range of naturally occurring environmental contamination conditions. The dataset was acquired using a multimodal sensing platform integrating LiDAR, perception RGB cameras, infrared camera sensors, and external monitoring systems, enabling comprehensive observation of sensor behavior under realistic operating environments. Based on this dataset, we propose a scalable contaminant classification framework that focuses on LiDAR surface contamination. A key contribution of this study is the introduction and exploitation of near-field point cloud features, which capture backscattered laser signals caused by surface contamination and exhibit a strong correlation with contamination severity and type. Using raw LiDAR signals, we utilize sixteen feature functions and train supervised learning models to classify seven distinct contaminant categories. Experimental results demonstrate that the proposed approach achieves classification accuracy exceeding 95% under real-world driving conditions, significantly outperforming prior laboratory-based studies. Furthermore, the framework is designed for practical deployment and can be extended to additional contaminant types and geographic regions through incremental data collection and learning. The proposed methodology enables real-time identification of LiDAR contamination sources, providing a critical foundation for adaptive sensor-cleaning strategies. By supporting contamination-aware sensor maintenance, this work contributes to cost- and weight-efficient sensor system design and represents an essential step toward achieving reliable Level 4 autonomous driving.
Kim, Hunjae
In-Situ Raman Measurements of Fuel Dilution of Lubricant Films in a Direct-Injection Spark-Ignition Engine2026-01-03554/7/2026
To measure the fuel proportion within the lubricant film, an in-situ Raman spectroscopy technique was employed in a specially modified single-cylinder direct-injection spark-ignition engine. The engine block was engineered for optical access with a fused silica window, enabling a focused laser beam to probe the lubricant film on the engine liner under motoring conditions. The lubricant used was GTL8 base oil with ZDDP additive, and iso-octane was injected as a model fuel to study fuel-lubricant mixing. A calibration curve was established by recording Raman spectra of known mixtures of GTL8 oil and iso-octane. The Raman intensity ratio of the iso-octane peak to the oil peak was used as a quantitative indicator of fuel concentration. During engine operation, Raman spectra were acquired in real time, on a cycle-by-cycle basis, through the optical window. Upon iso-octane injection, its characteristic Raman peak appeared in the spectrum, and the intensity ratio was referenced against the calibration curve to estimate the fuel proportion within the lubricant film. Experimental results demonstrated that the iso-octane signal could be detected during and after injection and this allowed for real-time monitoring of fuel dilution dynamics. The main challenge encountered was high fluorescence from oil, which sometimes obscured the Raman peaks and complicated quantification. Despite this, the technique successfully demonstrated the feasibility of direct, in-situ, and real-time quantification of fuel dilution in engine lubricant films, providing a valuable tool for studying fuel-lubricant interactions under operating engine conditions.
Bolle, Bastien, Augoye, Kobi, Wong, Janet, Aleiferis, Pavlos, Hall, Jonathan, Bassett, Mike, Cracknell, Roger
Undetectable Ship-to-Ship Laser CommunicationsTBMG-549224/1/2026
Astrolight recently demonstrated undetectable, unjammable, and high-bandwidth laser-based ship-to-ship communication with its POLARIS terminal during REPMUS’25, NATO’s largest unmanned maritime exercise.
A Thin-Film Flexible Temperature-Strain Multimodal Sensor for Lithium-Ion Battery Monitoring Based of Laser Direct Writing2026-01-70262/27/2026
Multimodal sensors, capable of simultaneously acquiring multiple physical or chemical signals, have shown broad application potential in fields such as health monitoring, soft robotics, and energy systems. However, current multimodal sensors often suffer from complex fabrication processes and signal decoupling challenges, which limit their practical deployment. To address these issues, this work presents a thin-film temperature–strain multimodal sensor (FTSMS) fabricated via laser processing. The temperature-sensing unit, based on the Seebeck effect, achieves a sensitivity of 9.08 μV/°C, while the strain-sensing unit, utilizing BaTiO₃/AlN@PDMS as the sensitive layer, exhibits a gauge factor (GF) of 43.2. By integrating distinct sensing mechanisms (thermovoltage for temperature and capacitance change for strain), the FTSMS enables self-decoupled measurements over 20–90 °C. Applied in LIB monitoring, it successfully captures real-time temperature and strain variations during charge-discharge cycles and provides multidimensional information throughout thermal runaway (TR) processes, enabling early TR warning and supporting safety-oriented battery design.
Wang, Ziwei, Li, Zhenglin, Gao, Yang, Xuan, Fuzhen
Aerospace Aluminum Laser Welding: Advancing Material Performance for the Future of FlightTBMG-545972/1/2026
Development of a New Methodology for Measuring the Dimensions of Lighting Components in Construction Equipment Vehicles (CEVs) as per IS/ISO 12509:2004 using 3-Dimensional Planar Laser2026-26-01451/16/2026
The light and light signaling devices installation test as per as per IS/ ISO 12509:2004 & IS/ISO 12509:2023 for Earth Moving Machinery / Construction Equipment Vehicles is a mandatory test to ensure the safety and comfort of both road users and operators. Considering the shape and size of construction equipment vehicles, accurate measurement of lighting installation requirements is crucial for ensuring safety and regulatory compliance. The international standard IS/ISO 12509:2004 & IS/ISO 12509:2023 outlines specific criteria for these installation requirements of lighting components, including the precise measurement of various dimensions to ensure optimal visibility and safety. Among these dimensional requirements, the dimension 'E' i.e., the “distance between the outer edges of the machine and the illuminating surface of the lighting device” plays a critical role in the performance of vehicle lighting systems. Traditional methods of measuring this dimension, such as using a measuring tape and long straight rod, in another method Using Rope, Plumb and Measuring tape have limitations in terms of precision and consistency due to machine size and shape. This paper presents a method development approach utilizing a 3-Dimensional planar laser for measuring dimension 'E' in Construction Equipment Vehicles (CEVs). Measurement through the planar laser method is found to offer significantly higher accuracy compared to conventional measuring techniques, particularly when applied to the complex shapes and sizes of CEV’s such as Motor Graders, Wheel Loaders and Backhoe Loaders. This approach not only enhances the measurement accuracy but also improves the efficiency of the testing process. The paper discusses the methodologies, results, comparison of 3 measuring methods and potential applications of Planar laser in the context of IS/ISO 12509:2004 & IS/ISO 12509:2023, offering a promising alternative method for future testing and certification of Construction Equipment Vehicle’s lighting systems.
Ghodke, Dhananjay Sunil, Belavadi Venkataramaiah, Shamsundara, Tambolkar, Sonali Ameya
Machine Learning Approach to ISO Road Class Prediction Using Multiple Linear Regression2026-26-06671/16/2026
The inertial profiler methodology is traditionally employed in RLDA (Road Load Data Acquisition) to measure road profiles and classify test routes into ISO road classes. However, this approach demands significant time and effort during instrumentation. Also, during data acquisition, laser height sensor data is affected especially during adverse conditions such as rainy seasons or on surfaces with improper reflectivity. Additionally, substantial resources are required for data processing to convert raw measurements into road classifications. To address these challenges, an initial attempt was made to establish a relationship between axle acceleration responses and road profiles, enabling axle acceleration measurements during RLDA to predict ISO road classes. However, this approach relied on a simple linear model that considered only axle acceleration responses, rendering the predictions susceptible to inaccuracies due to varying parameters such as vehicle speed. To overcome these limitations, an alternative method is introduced in this study, incorporating additional & generated parameters and employing a multiple linear regression model based on machine learning techniques. This paper outlines the detailed steps of the machine learning process, including feature engineering methods such as feature extraction, transformation, selection, and reduction. It also explores model fine-tuning strategies guided by performance metrics. The proposed methodology significantly improves the accuracy of road class predictions while reducing the time, effort, and challenges associated with instrumentation, data acquisition, and post-processing activities.
P, Praveen Kumar, P, Dayalan, Sriramulu, Yoganandam
Effect of Correlated Colour Temperature of Automotive LED Headlamps on Visibility and Safety2026-26-01301/16/2026
The objective of this study was to examine the effect of Correlated Colour Temperature (CCT) of automotive LED headlamps on driver’s visibility and comfort during night driving. The experiment was conducted on different headlamps having different correlated colour temperatures ranging from 5000K to 6500K in laboratory. Further study was conducted involving participants of different age group and genders for understanding their perception to identify objects when observed in light of different LED headlamps with different CCTs. Studies have shown that both Correlated Colour Temperature and illumination level affect driver’s alertness and performance. Further study required on headlamps with automatically varying CCT to get better solution on driver’s visibility and safety.
Patil, Mahendra G., Kirve, Jyoti, Parlikar, Padmakumar
Peering through Lunar Darkness: Laser Invention to Steer the Next Generation of Moon LandersTBMG-544551/1/2026
Advanced Navigation Sydney, Australia
Advances in Fiber Laser Welding for E-Mobility ManufacturingTBMG-544331/1/2026
High-power fiber lasers have become increasingly indispensable tools in automotive manufacturing over the past two decades. They are now widely deployed in welding and brazing applications for body-in-white, powertrains, engine components, and more.
Advanced High-Repetition-Rate Lasers Drive Next-Gen ImagingTBMG-544131/1/2026
Since the advent of laser-based imaging techniques in the early 2000s, image acquisition has faced a fundamental challenge: the imaging speed and signal averaging was directly tied to the firing rate of the laser. Because a minimum of one laser pulse generates a single data point, traditional flashlamp-based lasers operating at relatively low repetition rates were constrained in their ability to capture fine spatial or temporal detail quickly. For applications requiring real-time analysis or high-resolution mapping, these limitations often reduced the practicality of otherwise powerful imaging technologies.
Impact of Tire-Ground Contact Width on Pavement Roughness Evaluation2025-99-025612/23/2025
The International Roughness Index (IRI) is a key indicator for evaluating the performance of road surfaces. However, traditional measurement methods only focus on the evaluation data of a single longitudinal section and do not consider the lateral difference between the actual contact area between the tire and the road surface, which may lead to inaccurate evaluation results. In recent years, with the advancement of 3D laser scanning and digital photogrammetry technology, full-section data acquisition has brought new possibilities for roughness evaluation. However, how to find a balance between data fineness and computing efficiency has become a core problem that needs to be solved. Based on the principle of interaction between vehicles and road surfaces, this paper proposes to include only the pavement height data within the tire width range into IRI analysis, and establishes an evaluation framework based on standard tire-ground contact width. This method not only retains the key information of horizontal unevenness, but also increases the computing speed by reducing the amount of data. In the experiment, a vehicle-mounted three-dimensional measurement system was used to measure the height of the actual roads, and the variation patterns of IRI values under different contact widths were analyzed. The study found that the tire-ground contact width will affect the IRI calculation results, but the degree of impact varies according to the wheel position. The IRI value of the left wheel area is not sensitive to the change in contact width, while the IRI value will fluctuate significantly due to the lateral slope of the road surface or structural asymmetry in the right wheel area. We recommend that 200 mm be used as the recommended value for the tire-ground contact width, which can not only ensure the evaluation accuracy, but also improve detection efficiency.
An, Huazhen, Wang, Rui, Han, Xiaokun, Luo, Yingchao
Entangled-Photon Pairs Secure Optical CommunicationsTBMG-5429412/1/2025
NASA’s Glenn Research Center has developed a method of using entangled-photon pairs to produce highly secure mobile communications that require mere milliwatts of power. Conventional gas Argon-ion laser sources are too large, expensive, and power-intensive to use in portable applications. By contrast, Glenn’s patented optical quantum communication method produces entangled-photon pairs approximately a million times more efficiently than conventional sources, in a system that is small and light enough to be portable.
Influence of Laser Sintered Process Parameters on Crystalline Characteristics and Mechanical Properties of AlSi10Mg Alloy05-19-03-001911/3/2025
The present study examines the influence of process parameters on the effect of strength and crystalline properties of AlSi10Mg alloy with laser sintered process. A detailed work was carried out with the effects of varying the laser power, scan speed, and hatch distance on crystalline structure, hardness, and surface roughness. From the analysis, the improved surface quality and mechanical performance were achieved with a scan speed of 1200 mm/s, a laser power of 370 W, and a hatch distance of 0.1 mm. An increase in hardness, improved surface finish, and reduced porosity was observed with decreased hatch distance. However, the balanced results were obtained for scanning speed of 1200 mm/s and laser power of 370 W. The ideal processing conditions decreased the crystalline size, increasing the overall material strength, when crystalline analysis was carried out. The higher scanning speeds supported improved grain refinement and heat diffusion, with the poor hardness value. With the lower scanning speed below 1200 mm/s, the surface flaws like warping and porosity result from the excessive laser power.
Shailesh Rao, A.
Transient Helium Jet Evolution Using High Speed Schlieren Imaging2025-32-005711/3/2025
The accelerating global shift towards decarbonised energy systems has positioned hydrogen as a highly promising carbon-free fuel. This study comprehensively investigates the macroscopic characteristics and temporal evolution of vortex ring trailing helium jets, serving as a surrogate for hydrogen, injected into a quiescent ambient environment using high-speed Schlieren imaging. This research addresses critical insights into fuel-air mixing dynamics essential for optimising hydrogen direct injection (DI) internal combustion engines. Analysis of helium jet tip’s topology revealed a three-stage evolution from an initial pressure-insensitive phase, dominated by pressure wave structures, to a momentum-driven, vortex-dependent growth stage, then to a fully developed stage. Specifically, the lower-pressure cases showed increased Kelvin-Helmholtz instability and distinct head vortex pinch-off at the final stage. Jet tip velocities transitioned from initial high, rapid pressure wave development speeds to a momentum-controlled phase, with lower-pressure jets exhibiting greater fluctuations and susceptibility to Kelvin-Helmholtz instabilities effects. Jet width growth initially mirrored across pressures due to vortex ring expansion before diverging into a turbulent mixing regime, notably displaying a transient width reduction as internal ring structures dissipated. The jet angle stabilised around 32°, with higher injection pressures resulting in slightly narrower angles due to enhanced axial momentum. Overall, jet area growth was significantly faster and larger at higher injection pressures, confirming their superior mixing potential. These findings provide crucial insights into the interplay of injection parameters, vortex dynamics, and turbulent processes, advancing the fundamental understanding necessary for optimising fuel-air mixture formation and combustion efficiency in hydrogen DI engine development.
Dong, Shuo, Shi, Hao, Zhang, Gengxin, Feng, Yizhuo, Lu, Enshen, Wang, Xinyan, Zhao, Hua
Research on Network Control System for Heavy Duty Trains Based on Laser + Ethernet2025-99-005110/17/2025
Trains traditionally transmit braking and mitigation commands through the air tube filling and exhausting method, which is easy to cause local large longitudinal impact. In order to meet the high-precision requirements of synchronous transmission of commands for heavy-duty trains with large groupings, this paper proposes a laser+industrial Ethernet network control system, which can meet the requirements of flexible train grouping and virtual connecting under the premise of ensuring synchronous transmission of commands for trains with large groupings. The system consists of central control unit, locomotive laser communication module, locomotive switch, mobile wireless communication terminal, security gateway, vehicle control unit, vehicle laser communication module, vehicle switch, etc. It is designed according to the three-layer architecture of vehicle-level network, train-level network and line-level network, which can realise the issuance of internal control commands and status monitoring of the train, the real-time communication of the virtual train, as well as the information cloud sharing of the train running on the same line. Train information cloud sharing. As verified by the semi-physical test bench, the total transmission delay is less than 1.5ms, which is 5000 times higher than the transmission rate of traditional air tube, and the technical index meets the requirement of synchronous execution of commands for heavy-duty trains.
Meng, Xiangzhen, Li, Chuanhu, Zhu, Youlong
Reconstruction of Density Fields of Category L-Vehicles’ Exhaust Plumes for Optimizing Remote Emission Sensing and Engine Performance03-18-06-003610/7/2025
Air pollution is a significant long-term public health issue, with on-road traffic emissions being a primary contributor, especially in urban areas. Remote emission sensing (RES) is an innovative method for large-scale monitoring of vehicle emissions. It not only enables accurate detection of pollutants from vehicles under real-world driving conditions but also offers actionable insights to optimize engine performance. The point sampling-based RES technique involves sampling the vehicle exhaust plume along the roadside with a sampling line and using exhaust analyzers. In this method, the sampling line is placed alongside the road for sample extraction. Thus, the sampling position and knowledge regarding the spread of the exhaust plumes are crucial. Other modern RES systems utilize laser absorption spectroscopy to measure the pollutants in vehicle exhaust. For accurate absorption measurements, the laser’s height must align with the height of the exhaust plume, and the absorption length must be known. In this work, we present a gas density Schlieren imaging sensor (GDSIS) system designed to visually capture, quantitatively analyze, and reconstruct the density fields of exhaust plumes from category L-vehicles. By analyzing the density fields, we can pinpoint the location of the highest density within the exhaust plume. This information indicates the ideal height for positioning sampling lines and lasers used in RES systems. Identifying this ideal height can enhance the efficiency and capture rate of RES systems while also helping to detect engine inefficiencies that can negatively affect performance and increase emissions. Moreover, emission patterns can inform engine calibration or maintenance schedules, which helps optimize fuel consumption and engine response. The performance of the GDSIS system in both laboratory settings with controlled gas flows and on the road with L-vehicles during emissions measurement campaigns is evaluated.
Imtiaz, Hafiz Hashim, Liu, Yingjie, Schaffer, Paul, Kupper, Martin, Bergmann, Alexander
A Novel Mechanical Model Simulating a Pavement Deflection Measuring System for Non-Invasive Pavement Monitoring Based on a Reliability-Based Optimization Algorithm02-18-03-00259/4/2025
This article presents a novel mechanical model for simulating the behavior of pavement deflection measuring systems (PDMS). The accuracy of the model was validated by comparing the acceleration of the new model with the data achieved through experimental tests fusing a deflection measurement system mounted on a Ford F-150 truck. The experimental test for the PDMS is carried out on a random road profile, generated by an inertial profiler, over a 7.4-mile (12 km) loop around a lake near Austin, Texas. Integrating a reliability-based optimization (RBO) algorithm in a PDMS aims to optimize system parameters and reduce vibrations effectively. The PDMS noises and uncertainties make it crucial to use a robust system to ensure the stability of the system. This article presents a robust algorithm for considering the uncertainties of PDMS parameters, including the damping coefficients and spring stiffness of the supporting brackets. Moreover, it considers the variation of system parameters, such as stiffness of the vehicle’s tire and changing in the weight of the vehicle based on the number of passengers sitting in the cars. This approach ensures the system’s high accuracy and reliability, despite uncertainties and variations. Moreover, the presented algorithm calculates the optimum parameters of the PDMS model by minimizing the acceleration of the front and rear lasers and the rotation of the beam about the y-axis at the center of the beam. The accuracy of the RBO is being evaluated by comparing RBO with deterministic optimization methods. This comparison illustrates the accuracy of the RBO method for obtaining a more precise and reliable PDMS system. It also indicates the effectiveness of the RBO method in obtaining a more accurate and robust system, which can be utilized in real-world applications. RBO significantly minimizes the mean angular displacement of the beam (from 8.68° to 2.18°), as well as the RMS of front and rear accelerations (from 5.0 m/s2 to as low as 0.66 m/s2), based on variance reductions.
Yarmohammadisatri, Sadegh, Sandu, Corina, Claudel, Christian
Noninvasive Imaging Method Can Penetrate Deeper Into Living TissueTBMG-537019/1/2025
Metabolic imaging is a noninvasive method that enables clinicians and scientists to study living cells using laser light, which can help them assess disease progression and treatment responses. But light scatters when it shines into biological tissue, limiting how deeply it can penetrate and hampering the resolution of captured images.
A Technological Breakthrough for Ultra-Fast and Greener AITBMG-537029/1/2025
Artificial intelligence systems like ChatGPT are notorious for being power-hungry. To tackle this challenge, a team from the Centre for Optics, Photonics and Lasers (COPL) has come up with an optical chip that can transfer massive amounts of data at ultra-high speed. As thin as a strand of hair, this technology offers unrivaled energy efficiency.
Optimizing Laser Cutting in Semiconductor Advanced PackagingTBMG-537079/1/2025
Tunable Laser LightTBMG-537059/1/2025
Researchers in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Vienna University of Technology (TU Wien) have invented a new type of tunable semiconductor laser that combines the best attributes of today’s most advanced laser products, demonstrating smooth, reliable, wide-range wavelength tuning in a simple, chip-sized design.
Laser Welding for Polymer Tubing: A New Solution for Adhesive- and Additive-Free JoiningTBMG-537789/1/2025
Medical tubing is an essential component of countless healthcare applications, from intravenous (IV) and oxygen lines to catheters and diagnostic equipment. These tubes, often made of clear flexible polymers, must be produced to exacting standards: free of contaminants, strong under pressure, and biocompatible. However, the joining process to connect these tubes can introduce significant manufacturing challenges.
Tiny Microlaser Sensors Offer Supercharged BiosensingTBMG-537849/1/2025
Researchers have developed a 3D microprinted sensor for highly sensitive on-chip biosensing. The sensor, which is based on a polymer whispering-gallerymode microlaser, opens new opportunities for developing high-performance, cost-effective lab-on-a-chip devices for early disease diagnosis.
New Laser Technique Revolutionizes Ultra-High Ceramic Manufacturing for Spacecraft25AERP08_078/1/2025
Researchers have demonstrated a new technique that uses lasers to create ceramics that can withstand ultra-high temperatures, with applications ranging from nuclear power technologies to spacecraft and jet exhaust systems. North Carolina State University, Raleigh, NC A new technique that leverages the concept of sintering, can be used to create ceramic coatings, tiles or complex three-dimensional structures, which allows for increased versatility when engineering new devices and technologies. “Sintering is the process by which raw materials - either powders or liquids - are converted into a ceramic material,” says Cheryl Xu, co-corresponding author of a paper on this research and a Professor of Mechanical and Aerospace Engineering at North Carolina State University (NCSU). “For this work, we focused on an ultrahigh temperature ceramic called hafnium carbide (HfC). Traditionally, sintering HfC requires placing the raw materials in a furnace that can reach temperatures of at least 2,200 degrees Celsius - a process that is time-consuming and energy intensive.
New Laser Technique Revolutionizes Ultra-High Ceramic Manufacturing for SpacecraftTBMG-535898/1/2025
A new technique that leverages the concept of sintering, can be used to create ceramic coatings, tiles or complex three-dimensional structures, which allows for increased versatility when engineering new devices and technologies.
Space Laser Tech Maps Mysterious Nearshore TerrainTBMG-535468/1/2025
Despite all the technological evolution in navigation, waters just off coastal shores around the globe have remained a black box. That is, until researchers from The University of Texas at Austin and Oregon State University developed a new technology that uses satellites in space to map out these tricky areas.
Aerospace & Defense Technology: June 202525AERP066/5/2025
IQSat: Aitech’s AI-Enabled Picosatellite for Earth Observation and Imaging Applications Pushing the Boundaries of Rapid Production of Spacecraft: Flight Results from NearSpace Launch’s TROOP and ThinSat Platforms Transforming Satellite Antenna Technology for the Next Era of Aerospace and Defense Legacy in Action: The Enduring Role of MIL-STD-1553B Are Defense Satellites Ready for Space-Based Laser Communications? Microcomb Chips Could Improve Accuracy of GPS Systems Thermoelectric Generators Could Convert Waste Heat to Clean Energy in Jet Engines and Spacecraft Improving Electric Propulsion Thrusters for Future Spacecraft Missions A Satellite to Detect Short Gamma-Ray Burst Emissions In-Orbit Testing of Autonomous ‘Swarm’ Satellites NanoAvionics Satellite Suffers Space Debris Impact, Selfie Image Shows Damage
Advanced Laser Welding Techniques for Titanium Pacemaker Housing: Achieving Precision, Reliable and Hermetic SealingTBMG-532586/3/2025
A pacemaker is a small device that helps control your heartbeat so you can return to your normal life. It has three main parts: a pulse generator that creates electrical signals, a controller-monitor that manages these signals, and leads that deliver the signals to the heart. One key benefit of the pacemaker is its strong titanium casing. Titanium is very strong and lightweight, and it is biocompatible, meaning it works well with the body without causing harmful reactions. This metal is highly resistant to corrosion, which helps keep the casing intact and protective even when exposed to bodily fluids.
Ultra-Sensitive Sensor with Gold Nanoparticle ArrayTBMG-532236/1/2025
Researchers have developed a new type of sensor platform using a gold nanoparticle array. The sensor is made up of a series of gold disk-shaped nanoparticles on a glass slide. When an infrared laser is pointed at a precise arrangement of the particles, they start to emit unusual amounts of ultraviolet (UV) light.
Are Defense Satellites Ready for Space-Based Laser Communications?TBMG-532636/1/2025
Are Defense Satellites Ready for Space-Based Laser Communications?25AERP06_056/1/2025
The Department of Defense (DoD) is developing technology for satellites to communicate via lasers. Laser communications could transmit data faster and more securely than traditional radio frequency communications. DoD has made progress in developing this technology, but it has also faced delays and other issues-and hasn't fully demonstrated that it works in space. Despite these challenges, DoD plans to continue to develop and launch hundreds of satellites worth billions of dollars that require the use of laser communications.
Fast Steering Mirrors: Enabling Stable Laser Communication in Satellite NetworksTBMG-532216/1/2025
Wire Feed Laser Welding for Battery Pack Aluminum Enclosure Manufacture in EVsTBMG-532106/1/2025
Breakthrough in Long-Haul Laser Communication CapabilitiesTBMG-532716/1/2025
BlueHalo Albuquerque, NM Ashley.Young@bluehalo.com
Wire and Cable Marking Process, UV LaserAS5649B (Current)5/1/2025
This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber-optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 and which has been marked in accordance with this standard will conform to the requirements of AS50881.
AE-8A Elec Wiring and Fiber Optic Interconnect Sys Install
Scientists Propose Laser Scalpel with a ‘Curved’ BladeTBMG-530395/1/2025
Scientists from Tomsk Polytechnic University and Saratov State University teamed up with colleagues from Taiwan and proposed to make a laser “blade” for a medical scalpel with a specified curved shape using a photonic “hook.” Currently there are laser scalpels only with an axisymmetric focus area, i.e., with a cylindrical blade. According to scientists, changing the shape of the blade will expand the possibilities of using the laser in medicine, while it is about two times thinner than the cylindrical option. The concept and its rationale are published in the Journal of Biophotonics.
Items per page:
1 – 50 of 2265