Browse Topic: Fabrication

Items (2,755)
Recently, four-dimensional (4D) radar has shown unique advantages in the field of odometry estimation due to its low cost, all-weather use, and dynamic and static recognition. These features complement the performance of monocular cameras, which provide rich information but are easily affected by lighting. However, the construction of deep radar visual odometry faces the following challenges: (1) the 4D radar point cloud is very sparse; (2) due to the penetration ability of 4D radar, it will produce mismatches with pixels when projected onto the image plane. In order to enrich the point cloud information and improve the accuracy of modal correspondence, this paper proposes a low-cost fusion odometry method based on 4D radar and pseudo-LiDAR, 4DRPLO-Net. This method proposes a new framework that uses 4D radar points and pseudo-LiDAR points generated by images to construct odometry, bridging the gap between 4D radar and images in three-dimensional (3D) space. Specifically, the pseudo
Huang, MinqingLu, ShouyiZhuo, Guirong
One of the most common materials in the fabrication sectors, especially in the auto sector, is Aluminum alloy. Owing to its low strength to weight ratio, it could be a good fit for a number of applications. The cold working procedure may strengthen the 5XXX series Aluminum alloy, which is not heat treatable and it is also challenging to fuse these alloys together using fusion welding processes. In Recent days, a solid-state welding procedure, Friction Stir Welding (FSW) is used to join this alloy. The impact of FSW process parameters on tensile strength of the joint is examined in this study. Based on the outcomes of the experiment, the highest tensile strength is observed at 900 RPM tool rotation, 100 mm/min welding speed, 1.5-degree tilt angle, and 3.0 tool diameter ratio. Superior strength (246 MPa) of this parameter over its competitors can be attributed to the balanced material flow and the formation of finer grains in the weld region
Maram, Sreenivasulu ReddyKumar, M. VinothHariram, V.
Hybrid reinforcement-made polypropylene (PP) composites are beneficial over monolithic PP and utilized for various engineering and non-engineering applications. The present investigation of PP hybrid composites is developed with 10 percentages of weight (wt%) of E-glass fiber embedded with 0–6 wt% of silicon carbide via compression technique associated with hot press. E-glass fiber and SiC influencing wear rate, tensile strength, and microhardness behavior of PP and its composites are experimentally investigated. The peak loading of SiC as 6 wt% into PP/10 wt% E-glass fiber is recorded as better wear resistance (0.021 mm3/m), maximum tensile strength value (54.9 MPa), and highest hardness (68 HV). Moreover, the investigation results of hybrid PP composite are better resistance to wear and hiked tensile and hardness behavior compared to monolithic PP. This PP/10 wt% E-glass fiber/6 wt% of SiC hybrid composite is adopted for high-strength to lightweight sports goods applications
Venkatesh, R.
ABSTRACT Survivability of a welded vehicle hull is directly tied to the performance of the grade of steel armor used. Selecting the highest performing grade of armor that can be welded into a specific location on a vehicle will improve survivability. While rolled homogeneous armor is the simplest to weld, challenges in welding high hard, and especially ultra high hard, are well known. Preventative measures to avoid weld cracking in vehicle structures can lead to increased costs during fabrication. Cracking of welds, both seen and unseen, in deployed vehicles directly impacts the survivability of the vehicle. Weld cracking during deployment further magnifies repair costs and leads to non-mission capable status. This analysis examines the weldability, ballistic/blast performance, and underlying metallurgy of Flash® Processed steels that have been tested by Army, Academia, and Industry. Citation: G. Cola, “Flash® 600 Ultra High Hard: Room-Temp ER120S-1 Weldability Tekken, H-Plate
Cola, Gary M
Abstract The United State Army employs several advanced armored combat vehicles, in a wide array of different environments, and applications. Armor steels are hard and are required to meet certain conditions to stay within the military’s specifications for armored steels. Vehicle armor is typically joined using arc welding methods. Joining via arc welding degrades armor material below specification, so alternate joining methods are being explored like Friction Stir Welding (FSW). FSW is a solid-state joining technique that utilizes a rotating pin to stir plasticized material and use a tool shoulder to forge the material into the joint. The advantages come from the reduction in peak temperature, an increase in mechanical performance, and a decrease in possible defects that occur. In this study FSW parameters were developed and used to weld Wrought Homogenous Armor (HRA) steel. The welds were subject to hardness indention, and metallographic analysis to observe an early prediction of
Evans, WilliamRamirez, AntonioMcDonnell, MartinEff, Mike
ABSTRACT The International Council on Systems Engineering https://www.incose.org/ is a recognized standards body defining a system engineering knowledge-base, but this knowledge falls short of fully recognizing manufacturing in the Systems Engineering (SE) framework. To be inclusive, Manufacturing needs to join in the initiative of Model Based Systems Engineering to be relevant and succeed in the digital transformation in the field of systems engineering. This paper addresses this need in manufacturing by applying Model Based System Engineering (MBSE) to the identification and management of key characteristics so that a more relevant set of Manufacturing requirements can be introduced into the MBSE construct and help realize manufacturing resilience and become a full SE partner. Citation: “Identification and Management of Key Characteristics in Product Development Using Model Based Systems Engineering,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium
Ireland, William
ABSTRACT The University of Delaware (UD) and the US Army DEVCOM-GVSC (GVSC) have partnered to show the feasibility of fabricating mission specific, man-packable, autonomous vehicles that are created by Computer Aided Design (CAD) and are then produced, from start-to-finish, in a single manufacturing unit-cell without human intervention in the manufacturing process. This unit-cell contains many manufacturing processes (e.g., additive manufacturing (AM), pick-and-place, circuit printing, and subtractive manufacturing) that work in concert to fabricate functional devices. Together, UD and GVSC have developed the very first mission specific autonomous vehicle that is fully fabricated in a single manufacturing unit-cell without being touched by human hand. Citation: Jacob W. Robinson, Thomas W. Lum, Zachary J. Larimore, Matthew P. Ludkey, Larry (LJ) R. Holmes, Jr. “AUTOMATED MANUFACTURING FOR AUTONOMOUS SYSTEMS SOLUTIONS (AMASS)”, In Proceedings of the Ground Vehicle Systems Engineering and
Robinson, Jacob W.Lum, Thomas W.Larimore, Zachary J.Ludkey, Matthew P.Holmes, Larry (LJ) R.
ABSTRACT Flash® Bainite Processing employs rapid thermal cycling (<10s) to strengthen commercial off the shelf (COTS) steel sheet, plate, and tubing into Ultra Hard 600 Armor, High Hard 500 Armor, and advanced high strength steel (AHSS). In a continuous process, induction technology heats a narrow segment of the steel cross section in just seconds to atypically high temperature (1000-1300°C). Quenching substantially immediately follows. A report by Benet Labs and Picatinny Arsenal, investigating a less mature flash technology in 2011, surmised that the novel flash bainite process for steels has the potential to reduce cost and weight while also enhancing mechanical performance [1]. Receiving five financial grants, the US Dept of Energy has greatly matured flash technology in the last few years and its metallurgical understanding in collaboration with Oak Ridge National Lab and others. DOE has named Flash Bainite as the “SBIR Small Business of the Year” in May 2018 and awarded a Phase 3
Cola, Gary M
ABSTRACT The age of large autonomous ground vehicles has arrived. Wherever vehicles are used, autonomy is desired and, in most cases, being studied and developed. The last barrier is to prove to decision makers (and the general public) that these autonomous systems are safe. This paper describes a rigorous safety testing environment for large autonomous vehicles. Our approach to this borrows elements from game theory, where multiple competing players each attempt to maximize their payout. With this construct, we can model an environment that as an agent that seeks poor performance in an effort to find the rare corner cases that can lead to automation failure
Penning, RyanEnglish, JamesMelanz, DanielLimone, BrettMuench, PaulBednarz, David
ABSTRACT Increased fuel efficiency in military vehicles today results in two primary positive impacts to operational conditions. The first is the reduction in cost; both as a result of reduced fuel consumed and also in the costs saved due to the reduction in logistics required to transport fuel to the Warfighter in the field. The second and more important positive impact is the reduced risk of casualties to the Warfighter by reducing the frequency of fuel related logistical support required in the field. This paper first provides an overview of the development of the Fuel Efficient Demonstrator (FED) Bravo vehicle from initial conceptual efforts through to final operational shake-out and performance testing. A review the development process from CAD modeling through to fabrication and testing will be discussed. This discussion will also focus on the unique methods and ideas used to address the particular challenges encountered in developing a demonstrator vehicle. The paper concludes
Card, BrandonTodd, StevenBuchholz, William
Human body models have been used for decades to inform efforts in promoting automobile occupant and pedestrian safety. However, many of these models fail to capture the intricacies of individual variability. Cadaveric subjects typically exceed representative age ranges and hence mechanics. Animal subjects typically require specific setups that stray from that which is representative of human crash scenarios. Computational models can only consider so many practical real-world variables. Artificial surrogates, dummies being popular among them, are very popular for reusability and robust data collection. However, even the biomechanically accurate skeletal surrogates available commercially are limited in that they do not consider human variability and skeletal microstructure local variability. The objective of the work herein is to assess computational methods of metastructural variability mimicry by fabrication material. We implement mimicry approaches focusing on bulk isotropic
Hezrony, Benjamin S.C. F. Lopes, PedroBrown, Philip J.
This article presents experimental investigations and machine learning-based analysis on depositions of super duplex stainless steel (SDSS ER2594) material in wire arc additive manufacturing (WAAM) considering the process parameters namely voltage, wire feed rate, torch travel speed, and gas flow rate. Deposition efficiency and surface height values of the accumulated material were measured to build machine learning models using artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS). The developed ANN model could predict the deposition efficiency and surface height with mean absolute deviations (MADs) of 8.9% and 16.1%, respectively. The MAD for prediction of the two responses for ANFIS model was found to be 6.1% and 14.9% as compared to the experimental data. Multi-objective optimization was also performed to obtain optimal solutions to achieve desired deposition results. Mechanical properties and microstructures of the deposited materials with optimal
Kumar, PrakashMondal, SharifuddinMaji, Kuntal
Improvements in trace biological molecule detection can have significant impact on healthcare, food safety, and environmental safety industries. Detection of trace biological molecules can be critical to the diagnosis of early onset of diseases or infections. Researchers at NASA Ames Research Center developed an electrochemical, bead-based biological sensor based on Enzyme-Linked Immunosorbent Assay (ELISA) combining a magnetic concentration of signaling molecules and electrochemical amplification using wafer-scale fabrication of microelectrode arrays
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Goodin, ChrisCarruth, Daniel W.Dabbiru, LalithaHedrick, MichaelBlack, BrandonAspin, ZacharyCarrillo, Justin T.Kaniarz, John
The Software Production Factory (SPF) is a cyber physical construct of computers, hardware and software integrated together to serve as an ideation and rapid prototyping environment. SPF is a virtual dynamic environment to analyze requirements, architecture, and design, assess trade-offs, test Ground Vehicle development artifacts such as structural and behavioral features, and deploy system artifacts and operational qualifications. SPF is utilized during the product development as well as during system operations and support. The white paper describes the components of the SPF to build relevant Ground Vehicle Rapid Prototyping (GVRP) models in accordance with the model-centric digital engineering process guidelines. The factory and the processes together ensure that the artifacts are produced as specified. The processes are centered around building, maintaining, and tracing single source of information from source all the way to final atomic element of the built system
Thukral, AjayGriffin, Kevin W.Kanon, Robert J.
Photolithography involves manipulating light to precisely etch features onto a surface, and is commonly used to fabricate computer chips and optical devices like lenses. But tiny deviations during the manufacturing process often cause these devices to fall short of their designers’ intentions
To advance soft robotics, skin-integrated electronics, and biomedical devices, researchers have developed a 3D printed material that is soft and stretchable — traits needed for matching the properties of tissues and organs — and that self-assembles. Their approach employs a process that eliminates many drawbacks of previous fabrication methods, such as less conductivity or device failure
Engineers at UC Berkeley have developed a new technique for making wearable sensors that enables medical researchers to prototype and test new designs much faster and at a far lower cost than existing methods
To expand the availability of electricity generated from nuclear power, several countries have started developing designs for small modular reactors (SMRs), which could take less time and money to construct compared to existing reactors
The present work highlights the significance of nanocomposite coatings for their ease of processing and applicability in combating corrosion. Ongoing research is dedicated to the development of an effective nanocomposite hydrophobic coating. A hydrophobic nanocomposite coating was deposited on galvanized iron (GI) using a sol-gel route with polymethylsiloxane (PDMS) reinforced with nano-SiO2. Surface morphology and chemical composition analysis, conducted with scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FTIR), revealed the coating’s structural and compositional attributes. The resulting hydrophobic coating exhibits a water contact angle (WCA) of 104.1°, indicating a 30.45% increase compared to bare GI. Subsequent to these characterizations, the adhesion of the coated GI, rated as 4B per ASTM D3359, is followed by commendable resistance to corrosion, as evidenced by electrochemical tests. The corrosion rate
Kumar, PrakashRamesh, M.R.Doddamani, Mrityunjay
To improve battery performance and production, Penn State researchers and collaborators have developed a new fabrication approach that could make for more efficient batteries that maintain energy and power levels
The photochemical etching (PCE) process is distinguished by its capacity to fabricate metal parts with unparalleled accuracy. This process sidesteps the typical stresses and deformations linked to conventional metal-working, like stamping or laser cutting, which can compromise material integrity. Such fidelity is crucial in the manufacture of components for thermal management systems, where material integrity and component precision are non-negotiable for ensuring effective heat creation or dissipation. PCE’s ability to craft parts with smooth, burr-free edges and exact dimensions means heat management components work more effectively, bolstering the reliability and extending the service life of micro electronic devices
Bio-composites have gained significant attention within the aerospace industry due to their potential as a sustainable solution that addresses the demand for lightweight materials with reduced environmental impact. These materials blend natural fibers sourced from renewable origins, such as plant-based fibers, with polymer matrices to fabricate composite materials that exhibit desirable mechanical properties and environmental friendliness. The aerospace sector's growing interest in bio-composites originates from those composites’ capacity to mitigate the industry's carbon footprint and decrease dependence on finite resources. This study aims to investigate the suitability of utilizing plant-derived flax fabric/PLA (polylactic acid) matrix-based bio-composites in aerospace applications, as well as the recyclability potential of these composites in the circular manufacturing economy. The bio-composite laminate is produced through a compression molding process involving interleaved layers
B S, DakshayiniKancherla, Kishore BabuRaju, BenjaminRoy Mahapatra, Debiprosad
Light is used in many ways in sensor technology for high precision applications. For example, white light technology can be used for confocal chromatic sensors and interferometers that can make extremely precise and accurate measurements of distance and thickness down to the sub-nanometer range. This makes them suitable for production monitoring in different industries, including semiconductor fabrication. However, even though both sensor types work with white light technology, the two measurement methods differ significantly, although they complement each other
This technical paper reports the development of an automatic defect detector utilizing deep learning for “polished skins”. Materials with a “polished skin” are used in the fabrication of the external plates of commercial airplanes. The polished skin is obtained by polishing the surface of an aluminum clad material, and they are visually inspected, which places a significant burden on inspectors to find minute defects on relatively large pieces of material. Automated inspection of these skins is made more difficult because the material has a mirror finished surface. Defects are broadly classified into three categories: dents, bumps, and discolorations. Therefore, a defect detector must be able to detect these types of defects and measure the defects’ surface profile. This technical paper presents details related to the design and manufacture of an inexpensive automated defect detector that demonstrates a sufficiently high level of performance. The system employs multiple line sensor
Aoki, NaofumiOta, TakuyaZaitsu, Masayoshi
Additive manufacturing enables unrivaled design freedom and flexible fabrication of components from a wide range of materials including metals, composites, polymers, and ceramics. The near net shape parts are made by processes like sequential melting or layer-by-layer material deposition with a complex set of processing variables. The sequential nature of the process means that every step can impact the next and thus, tools to evaluate that risk before and during manufacturing are necessary
Equal Channel Angular Pressing is proven to produce ultrafine-grained to nano-structured materials and is most advantageous in comparison with most severe plastic deformation processes, due to its multi-pass capability. The channel angle is the most dominant process parameter, depending on which the property of the processed material varies significantly. Hence to exploit the advantage of this process and to fabricate materials with tailor-made properties, it is desirable to have access to a wide range of channel angles. Limitations in existing designs restrict this to one fixed angle per die and a variation of the angle demands an entirely new die. Hence a novel die geometry is proposed, where the exit channel is made detachable from the parent die block, permitting flexibility of channel angle. Such a design cuts down the cost of fabricating a die setup for the desired channel angle by as much as 80%, in comparison with the traditional split die configuration where a whole new die
Balasubramanian, M.Prathap, P.Madhu, S.
The basic needs of people are met by the building, fabric, and farming sectors. In addition, the automobile industry significantly contributes to human mobility and is essential to India’s economic expansion. There are numerous research strategies available to improve the bus body building industries. Several investigative approaches for enhancing bus body building industries are available. However, several of these studies merely look at it from the perspective of shop floor activity. Accordingly, when it comes to the execution of process design approaches, there is little practical evidence for accepting Gemba kaizen’s attitude. Hence, the purpose of this article is to present a continuous improvement redesign framework tailored to a specific bus body building industrial sector. The proposed model is structured after a critical examination of Gemba and Kaizen. The results showed that by implementing the improvement initiatives, the number of process activities decreased from 44 to 25
Balakrishnan, S.Senthilkumar, K.Rajkumar, V.Jerold John Britto , J.
The experimental investigation aims to improve natural composite materials aligned with feasible development principles. These composites can be exploited across several industries, including the automobile and biomedical sectors. This research employs date seed powder and neem gum powder as reinforcing agents, along with polyester resin as the base material. The fabrication route comprises compression moulding, causing the production of the natural composite material. This study focuses extensively on mechanical characteristics such as tensile strength, flexural strength, hardness, and impact resistance to undergo comprehensive testing. Furthermore, the chemical properties of the composites are examined using the FTIR test to gain understanding by integrating different proportions of date seed powder (5%, 10%, 15%, and 20%) and neem gum powder (0%, 3%, 6%, and 9%) in the matrix phase. These investigation goals are to evaluate the strength and performance of the fabricated composite
DINESH, D.Boopathiraja, K.P.Rajamurugan, G.Ramamoorthi, R.Yuvaraj, K.P.Babu, N.
A crucial characteristic of composites, which are manufactured from elements of metal, is their mechanical and durability properties. A variety of reinforcing agents and metal nanoparticles are used to create aluminum-based hybrid metal-material composites. These composites are an advantageous alternative for sectors with limited resources because of their robustness, wear resistance, and thermal management capabilities. Manufacturing sectors employ Taguchi optimisation and Grey relational analysis to enhance the mechanical and durability properties of aluminum-based hybrid metal composites. To comprehend the interrelationships between reinforcing materials such as Al2O3 and SiC at constant fly ash concentration, five responses such as wear loss, tensile strength, elongation rate, impact strength, and hardness were considered and assessed. The Grey Relational Analysis (GRA) method is used to optimise these responses and transform them into Grey Relational Grade (GRG). The Grey
Hemanth Kumar, R.Venkatachalapathy, V.S.K.Arumugam, ThiagarajanLAZAR, MARTIN
Additive manufacturing (AM) is a common way to make things faster in manufacturing era today. A mix of polypropylene (PP) and carbon fiber (CF) blended filament is strong and bonded well. Fused deposition modeling (FDM) is a common way to make things. For this research, made the test samples using a mix of PP and CF filament through FDM printer by varying infill speed of 40 meters per sec 50 meters per sec and 60 meters per sec in sequence. The tested these samples on a tribometer testing machine that slides them against a surface with different forces (from 5 to 20 N) and speeds (from 1 to 4 meters per sec). The findings of the study revealed a consistent linear increase in both wear rate and coefficient of friction across every sample analyzed. Nevertheless, noteworthy variations emerged when evaluating the samples subjected to the 40m/s infill speed test. Specifically, these particular samples exhibited notably lower wear rates and coefficients of friction compared to the remaining
Surendra, S.Sireesha, S.C.P., SivaSuresh, P.
Intelligent construction has become an important way to accelerate the transformation and upgrading of the construction industry and promote the high-quality development of the construction industry. As a national pilot city of intelligent construction, Shenyang needs effective policy system support for the development of intelligent construction. Quantitative research of policy text can provide a decision-making basis and path optimization suggestions for formulating and improving intelligent construction incentive policies (ICIP) in Shenyang. This study uses text mining and the Policy Modeling Consistency index (PMC index) model to construct an intelligent construction policy index system. Then it combines the PMC index and PMC surface to evaluate and analyze the text of ICIP in Shenyang quantitatively. The results show that there is still room for improvement in the ICIP in Shenyang. Accordingly, countermeasures and suggestions are put forward for policymakers, enterprises, and
Qi, YizhuoyanLi, LihongKong, Fanwen
Working on the nanoscale gives researchers a lot of insight and control when fabricating and characterizing materials. In larger scale manufacturing, as well as in nature, many materials have the capacity for flaws and impurities that can disrupt their complex structure. This creates several weak points that can easily break under stress. This is common with most glass, which is why it is thought of as such a delicate material
In recent years, industry adoption of thermoplastic composites (TPCs) in lieu of thermosets and metallic structures has increased for the fabrication of air and launch vehicle components. Manufacturing of TPCs, performed via automated tape laying (ATL) and automated fiber placement (AFP), uses machines that place prepreg tow or tapes on molds in a unidirectional manner, which then undergo cure cycles, autoclaving, and other steps that require special tooling. The process is time, material, and energy intensive, requires large facilities to house equipment, and limits the size, mechanical properties and shapes of the parts manufactured. To address these limitations, NASA’s Langley Research Center has developed a simplified, tool-less automated tow/tape placement (ATP) system
In the rapidly evolving era of software and autonomous driving systems, there is a pressing demand for extensive validation and accelerated development. This necessity arises from the need for copious amounts of data to effectively develop and train neural network algorithms, especially for autonomous vehicles equipped with sensor suites encompassing various specialized algorithms, such as object detection, classification, and tracking. To construct a robust system, sensor data fusion plays a vital role. One approach to ensure an ample supply of data is to simulate the physical behavior of sensors within a simulation framework. This methodology guarantees redundancy, robustness, and safety by fusing the raw data from each sensor in the suite, including images, polygons, and point clouds, either on a per-sensor level or on an object level. Creating a physical simulation for a sensor is an extensive and intricate task that demands substantial computational power. Alternatively, another
Yousif, Ahmed Luay YousifElsobky, Mohamed
4D millimeter wave radar is a high-resolution sensor that has a strong perception ability of the surrounding environment. This paper uses millimeter wave radar point cloud to establish a static probabilistic occupancy grid map for static environment modeling. In order to obtain a clean occupancy grid map, we classify the point cloud according to the result of dynamic point clustering and project the classified point cloud into the grid map. Based on the distribution and category of millimeter wave radar point cloud, we propose a calculation model of grid occupancy probability. After obtaining the occupancy probability according to the calculation model, we calculate the posterior occupancy probability by using the motion law of self-vehicle and Bayesian filtering, and construct a stable probabilistic occupancy grid map. We test the method on real roads, and the results show that the proposed method can effectively suppress the influence of noise points on the quality of grid map, and
Liu, ChangLu, XinfeiXue, DanWu, Li
Positioning system is a key module of autonomous driving. As for LiDAR SLAM system, it faces great challenges in scenarios where there are repetitive and sparse features. Without loop closure or measurements from other sensors, odometry match errors or accumulated errors cannot be corrected. This paper proposes a construction method of LiDAR anchor constraints to improve the robustness of the SLAM system in the above challenging environment. We propose a robust anchor extraction method that adaptively extracts suitable cylindrical anchors in the environment, such as tree trunks, light poles, etc. Skewed tree trunks are detected by feature differences between laser lines. Boundary points on cylinders are removed to avoid misleading. After the appropriate anchors are detected, a factor graph-based anchor constraint construction method is designed. Where direct scans are made to anchor, direct constraints are constructed. While in the position where the anchor is not directly observed
Shen, XiangxiangLu, XiongZhu, JiaqiGao, LetianWu, JunxianLu, Yishi
To improve battery performance and production, Penn State researchers and collaborators have developed a new fabrication approach that could make for more efficient batteries that maintain energy and power levels
Centimeter-scale walking and crawling robots are in demand both for their ability to explore tight or cluttered environments and for their low fabrication costs. Now, pulling from origami-inspired construction, researchers led by Cynthia Sung, Gabel Family Term Assistant Professor in Mechanical Engineering and Applied Mechanics, have crafted a more simplified approach to the design and fabrication of these robots
In this article, we present a spatiotemporal trajectory planning algorithm for emergency obstacle avoidance. Utilizing obstacle and driving environment data from the sensing module, we construct a 3D spatiotemporal grid map. This informs our improved hybrid A* algorithm, which identifies collision-safe, dynamically feasible trajectories. The traditional hybrid A* algorithm is enhanced in three significant ways to make the search practical and feasible: (1) optimizing search efficiency with motion primitives based on child node acceleration, (2) integrating collision risk into the heuristic function to reduce ineffective node exploration, and (3) introducing a One-Shot search based on the Optimal Boundary Value Problem (OBVP) to improve goal state searches. Finally, the algorithm is tested in two scenarios: (1) a vehicle cut-in from an adjacent lane and (2) a pedestrian crossing. Simulation results indicate that our proposed emergency obstacle avoidance trajectory planning method can
Chen, GuoyingYao, JunGao, ZhenhaiGao, ZhengZhao, XuanmingXu, NanHua, Min
Nylon polymer with an optimal blend of Kevlar, fiberglass, and high-speed, high temperature (HSHT) Fiberglass offers improved characteristics such as flexural strength, wear resistance, electrical insulation, shock absorption, and a low friction coefficient. For this reason, the polymer composite manufactured by combining HSHT, Kevlar, and fiberglass with nylon as base material will expand the uses of nylon in the aerospace, automotive, and other industrial applications related to ergonomic tools, assembly trays, and so forth. The proposed work was carried out to investigate the continuous fiber reinforcement (CFR) in nylon polymer using a dual extrusion system. Twenty experimental runs were designed using a face-centered central composite design (FCCD) approach to analyze the influence of significant factors such as reinforcement material, infill pattern, and fiber angle on the fabricated specimen as per American Society for Testing Materials (ASTM) standards. The tensile strength
Kaushik, AshishKumar, PardeepGahletia, SumitGarg, Ramesh KumarKumar, AshishYadav, MohitGiri, JayantChhabra, Deepak
The 3D printing technology is an Additive Manufacturing process which is capable of producing the complex shapes. At present there is no other technologies integrating the 3D printing and the CNC machine, thus we adapting a new design of 3D printing setup for CNC machine with some special feature as extruder, it is based on the Fusion Deposition Modelling (FDM) process with the help of the parts like Extruder, Heat Bed, Arduino boards where we are going to design a head of the printer which is to be attached with the BT40 commonly used Tool holder for the CNC milling machines. This extruder plays a vital role in this CNC milling machine for producing 3D printed components of different material and different colour. And this setup is capable of printing high resolution and complex shapes with different material and different colour by means of the heated filament. The post processing process like milling and surface finish can also be done by the CNC Machine. This setup is cost
Deepan Kumar, SadhasivamS, BalakrishnanSaminathan, SathiskumarArun Raj, VDhayaneethi, SivajiE, SoundrapandianVeath Prakash, B
Magnesium alloy, known for its high strength and lightweight properties, finds widespread utilization in various technical applications. Aerospace applications, such as fuselages and steering columns, are well-suited for their utilization. These materials are frequently employed in automotive components, such as steering wheels and fuel tank lids, due to their notable corrosion resistance. The performance of magnesium alloy components remains unimproved by normal manufacturing methods due to the inherent characteristics of the material. This work introduces a contemporary approach to fabricating complex geometries through the utilization of Wire-Electro Discharge Machining (WEDM). The material utilized in this study was magnesium alloy. The investigation also considered the input parameters associated with the Wire Electrical Discharge Machining (WEDM) process, specifically the pulse duration and peak current. The findings of the study encompassed the material removal rate and surface
Natarajan, ManikandanPasupuleti, ThejasreeD, PalanisamyKumar, VKiruthika, JothiPolanki, Vamsinath
Since there are no typical working conditions in the field of engineering vehicles, this paper implements the construction of driving conditions based on Markov stochastic model and energy management strategy of a multi-mode hybrid mine dump truck based on dynamic programming algorithm under this background. Firstly, on the basis of existing vehicle driving data, we calculate the velocity transfer probability matrix with the Markov stochastic model, and then construct the vehicle driving condition after predicting the velocity. The constructed working conditions are applied to the energy management strategy of dynamic programming algorithm to calculate the energy consumption of the hybrid mining truck. It is proved that this construction method can be applied to the hybrid electric mine dump truck, and the DP based energy management strategy has lower energy consumption
Jiang, Y.T.Zhao, XinxinZhang, J.G.
This specification covers elemental copper in the form of powder (see 8.5
AMS D Nonferrous Alloys Committee
A research team has successfully overcome the limitations of soft strain sensors by integrating computer vision technology into optical sensors. The team developed a sensor technology known as computer vision-based optical strain (CVOS). Unlike conventional sensors reliant on electrical signals, CVOS sensors employ computer vision and optical sensors to analyze microscale optical patterns, extracting data regarding changes. This approach inherently enhances durability by eliminating elements that compromise sensor functionalities and streamlining fabrication processes, thereby facilitating sensor commercialization
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