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Viewing 241 to 270 of 8953
2016-04-05
Journal Article
2016-01-0336
R.J. Urbanic, R. Hedrick, Ana M. Djuric
Abstract When performing trajectory planning for robotic applications, there are many aspects to consider, such as the reach conditions, joint and end-effector velocities, accelerations and jerk conditions, etc. The reach conditions are dependent on the end-effector orientations and the robot kinematic structure. The reach condition feasibility is the first consideration to be addressed prior to optimizing a solution. The ‘functional’ work space or work window represents a region of feasible reach conditions, and is a sub-set of the work envelope. It is not intuitive to define. Consequently, 2D solution approaches are proposed. The 3D travel paths are decomposed to a 2D representation via radial projections. Forward kinematic representations are employed to define a 2D boundary curve for each desired end effector orientation.
2016-04-05
Journal Article
2016-01-0337
Ana M. Djuric, R.J. Urbanic, J.L. Rickli
Abstract Contemporary manufacturing systems are still evolving. The system elements, layouts, and integration methods are changing continuously, and ‘collaborative robots’ (CoBots) are now being considered as practical industrial solutions. CoBots, unlike traditional CoBots, are safe and flexible enough to work with humans. Although CoBots have the potential to become standard in production systems, there is no strong foundation for systems design and development. The focus of this research is to provide a foundation and four tier framework to facilitate the design, development and integration of CoBots. The framework consists of the system level, work-cell level, machine level, and worker level. Sixty-five percent of traditional robots are installed in the automobile industry and it takes 200 hours to program (and reprogram) them.
2016-04-05
Journal Article
2016-01-0359
Jeff Wang, Charles Enloe, Jatinder Singh, Curt Horvath
Abstract Impact toughness (or resistance to fracture) is a key material property for press hardened steel used in construction of the safety-critical elements of automotive body structures. Prior austenite grain size, as primarily controlled by the incoming microstructure and austenitization process, is a key microstructural feature that influences the impact toughness of press hardened steel. In this paper, a special Charpy V-notch impact test is developed to quantify the impact toughness of press hardened steel sheets with various prior austenite grain sizes, by stacking a number of thin sheets via mechanical riveting. Both the ductile-to-brittle transition temperature and upper shelf energy are analyzed in an effort to establish a correlation between impact toughness and prior austenite grain size. Within tested conditions, impact performance shows only a slight decrease as the prior austenitic grain size increases from 18 to 38 microns.
2016-04-05
Journal Article
2016-01-0356
Hua-Chu Shih
Prephosphated steels have been developed by applying the phosphate coating on zinc coated sheet steels to increase the lubricity in the automotive stamping process and adding extra corrosion protection. The prephosphate coating was also found to be able to further absorb the lubricant, which can reduce the oil migration and excessive amount of lubricant dripping on the die surface and the press floor. Due to its enhanced lubricity characteristic, the applications have been expanded to more-recently developed advanced high strength steels (AHSS). Because of the higher strength of AHSS, it is crucial to understand their performance under more extreme forming conditions such as higher die temperature, contact pressure and sliding speed, etc. The intent of this study is to investigate the tribological performance and die wear behavior of prephosphated AHSS in the die tryout and production conditions.
2016-04-05
Journal Article
2016-01-0344
Mohamed El-Sayed
Abstract Success in lean product realization depends on the ability to specify value from the voice of the customer at the beginning of the process. Value streaming, is therefore essential for assuring that the specified value is being pursued and achieved throughout the process. During lean implementation, however, it is usually assumed that nothing but value will be streamed if wastes are eliminated using value stream mapping. While waste elimination is necessary to make the process leaner and facilitate value streaming it is not sufficient for assuring that specified value is being streamed without structured and formalized participation of customers. With current structure of product realization processes, the voice of the customer is provided during the planning phase at the beginning of the process and customer satisfaction feedback is provided after product launch.
2016-04-05
Journal Article
2016-01-0363
HaiYan Yu, ZeZhen He, JiaYi Shen
Abstract The work-hardening response of TRIP780 steel subjected to strain-path changes was investigated using two-stage tension experiments. Large specimens were prestrained and then sub-sized samples were subjected to tension along various directions. The influence of strain-path changes on flow stress and work hardening performance was discussed in detail. The specific plastic work was calculated to compare the kinematic hardening behaviour after strain-path changes. The results showed that transient hardening was observed for TRIP780 sheets subjected to orthogonal strain-path change. The strain-hardening exponent (n-value) was influenced by prestraining levels and the strain path. The n-value exhibited a greater decrease under an orthogonal strain-path change. Prestraining can delay the onset of high work hardenability of TRIP steels. It is meaningful for the safety design of vehicles.
2016-04-05
Journal Article
2016-01-0361
Takeki Matsumoto, Nan Li, Xin Shi, Jianguo Lin
Abstract To reduce the fuel consumption as well as to improve the crash safety of vehicles, the usage of hot stamping parts is increasing dramatically in recent years. Aisin Takaoka has produced hot stamping parts since 2001 and has developed various technologies related to Hot Stamping. In an actual hot stamping process, parts with insufficient strength could be produced sometimes at a prototyping phase, even under the proper forming conditions. In order to understand these phenomena, in this paper, phase transformation in a boron steel 22MnB5 under various cooling rates were investigated and the effects of pre-strain conditions on the phase transformations were characterised. Uniaxial tensile specimens were stretched under isothermal conditions to different strain levels of 0-0.3, at strain rates of 0.1-5.0/s and deformation temperatures of 650-800°C.
2016-04-05
Journal Article
2016-01-0360
Cédric Georges, Xavier Vanden Eynde, Frank Goodwin
Advanced high strength steels used in automotive body and structure applications are exposed to hydrogen during several steps of their processing. For galvanized sheet steel, one of these is the continuous galvanizing process, during which the sheet is prepared for coating in a H2-N2 furnace. This paper shows the relationship between hydrogen uptake in DP600 and DP980 grades, together with an IF steel control composition, and galvanizing process conditions. Hydrogen uptake is strongly dependent on the furnace atmosphere and the amount of martensite in the steel but has little dependence on the soaking time, the humidity of the furnace atmosphere, or the temperature within the usual intercritical annealing range. Rapid outgassing was observed during overageing prior to the zinc dipping. Slow strain rate tests showed that there was no loss of ductility in galvanized samples that had been treated in a 5% H2 atmosphere or that had been overaged before the galvanizing.
2016-04-05
Journal Article
2016-01-0374
Zhigang Wei, George Zhu, Litang Gao, Limin Luo
Vehicle exhaust components and systems under fatigue loading often show multiple failure modes, which should be treated, at least theoretically, with rigorous advanced bi-modal and multi-modal statistical theories and approaches. These advanced methods are usually applied to mission-critical engineering applications such as nuclear and aerospace, in which large amounts of test data are often available. In the automotive industry, however, the sample size adopted in the product validation is usually small, thus the bi-modal and multi-modal phenomena cannot be distinguished with certainty.
2016-04-05
Journal Article
2016-01-0371
Wenkai Li, Carlos Engler-Pinto, Haitao Cui, Weidong Wen, Xuming Su
Abstract In this paper, fatigue tests on a cast aluminum alloy (AS7GU-T64) were performed under different frequencies and humidity levels. Tests conducted under conventional frequency in laboratory air have been compared to tests conducted under ultrasonic frequency in dry air, saturated humidity and in distilled water. It was observed that the highest and lowest fatigue lives correspond to ultrasonic fatigue tests in dry air and in distilled water, respectively. Unlike specimens tested at conventional frequency, all of the specimens tested at ultrasonic frequency presented a large amount of slip facets on the fatigue crack propagation fracture surface.
2016-04-05
Journal Article
2016-01-0420
Frank Anthony Cuccia, James Pineault, Mohammed Belassel, Michael Brauss
Abstract It is well known that manufacturing operations produce material conditions that can either enhance or debit the fatigue life of production components. One of the most critical aspects of material condition that can have a significant impact on fatigue life is residual stress (RS) [1, 2]. When springs are manufactured, the spring stock may undergo several operations during production. Additional operations may also be introduced for the purpose of imparting the spring with beneficial surface RS to extend its fatigue life and increase its ability to execute the task it was designed to perform. The resultant RS present in production springs as a result of the various fabrication and processing operations applied can be predicted and modeled, however, RS measurements must be performed in order to quantify the RS state with precision.
2016-04-05
Journal Article
2016-01-0504
Shin-Jang Sung, Jwo Pan
Abstract Analytical stress intensity factor solutions for welds in lap-shear specimens of equal thickness under pinned and clamped loading conditions based on the beam bending theory are presented and examined. Finite element analyses are also employed to obtain the stress intensity factor solutions for welds in lap-shear specimens under both clamped and pinned loading conditions. The computational solutions are compared well with the analytical solutions. The results of the analytical and computational solutions indicate that the bending moments at the clamped edges reduce the mode I and II stress intensity factor solutions by about 7% to 10% for the given specimen geometry. The effects of the clamped grips depend on the ratio of the weld width to the specimen length. Comparisons of the stress intensity factor solutions suggest that the fatigue lives of the welds in lap-shear specimens under clamped loading conditions should be higher than those under pinned loading conditions.
2016-04-05
Journal Article
2016-01-0505
Pai-Chen Lin, Shihming Lo
Abstract A concept of combining friction stir spot welding (FSSW) and clinching, denoted as friction stir clinching (FSC), was proposed to join alclad 2024-T3 aluminum sheets. A tool, having a smooth probe and a flat shoulder, and a die, having a circular cavity and a round groove, were used to make FSC joints. The failure loads and fatigue lives of FSC joints made by various punching depths, rotational speeds, and dwelling times, were evaluated to obtain the admissible processing parameters. Optical micrographs of the FSC joints, before and after failure, were examined to understand the effects of processing parameters on the mechanical interlock and alclad layer distribution, which strongly correlate to the failure load, failure mode, and fatigue life of FSC joints. Finally, the static and fatigue performance of FSC joints made by the admissible processing parameters was obtained. The feasibility of the FSC process for alclad 2024-T3 aluminum sheets was confirmed.
2016-04-05
Journal Article
2016-01-0506
Daisuke Tomomatsu
Abstract This study developed technology for simultaneously welding heterogeneous resin tubes in order to weld and integrate resin tubes with two different specifications (low temperature and high temperature). The aim of integration was cost and weight reduction. The cost reduction due to reducing the number of parts exceeded the increase in material cost due to a change to resin materials. Base material fracture of the resin tubes was set as the breaking format condition, and the welding parameters of the joint part rotations and the friction time between the joint part and the resin tubes were specified as the weld strength judgment standard. In addition, the fused thickness determined by observing the cross-section after welding was specified as the weld quality judgment standard. The range over which weld boundary peeling does not occur and weld strength is manifest was clarified by controlling the welding parameters and the fused thickness.
2016-04-05
Journal Article
2016-01-0498
Yang Li, Qiangsheng Zhao, Mansour Mirdamadi, Danielle Zeng, Xuming Su
Abstract Woven fabric carbon fiber/epoxy composites made through compression molding are one of the promising choices of material for the vehicle light-weighting strategy. Previous studies have shown that the processing conditions can have substantial influence on the performance of this type of the material. Therefore the optimization of the compression molding process is of great importance to the manufacturing practice. An efficient way to achieve the optimized design of this process would be through conducting finite element (FE) simulations of compression molding for woven fabric carbon fiber/epoxy composites. However, performing such simulation remains a challenging task for FE as multiple types of physics are involved during the compression molding process, including the epoxy resin curing and the complex mechanical behavior of woven fabric structure.
2016-04-05
Journal Article
2016-01-0499
Xu Zhang, Jennifer Johrendt
Abstract Successful manufacture of Carbon Fibre Reinforced Polymers (CFRP) by Long-Fibre Reinforced Thermoplastic (LFT) processes requires knowledge of the effect of numerous processing parameters such as temperature set-points, rotational machinery speeds, and matrix melt flow rates on the resulting material properties after the final compression moulding of the charge is complete. The degree to which the mechanical properties of the resulting material depend on these processing parameters is integral to the design of materials by any process, but the case study presented here highlights the manufacture of CFRP by LFT as a specific example. The material processing trials are part of the research performed by the International Composites Research Centre (ICRC) at the Fraunhofer Project Centre (FPC) located at the University of Western Ontario in London, Ontario, Canada.
2016-04-05
Journal Article
2016-01-0501
Seung Hoon Hong, Frank Yan, Shin-Jang Sung, Jwo Pan, Xuming Su, Peter Friedman
Abstract Failure mode and fatigue behavior of flow drill screw (FDS) joints in lap-shear specimens of aluminum 6082-T6 sheets with and without clearance hole are investigated based on experiments and a structural stress fatigue life estimation model. Lap-shear specimens with FDS joints were tested under cyclic loading conditions. Optical micrographs show that the failure modes of the FDS joints in specimens with and without clearance hole are quite similar under cyclic loading conditions. The fatigue lives of the FDS joints in specimens with clearance hole are longer than those of the FDS joints in specimens without clearance hole for the given load ranges under cyclic loading conditions. A structural stress fatigue life estimation model is adopted to estimate the fatigue lives of the FDS joints in lap-shear specimens under high-cycle loading conditions.
2016-04-05
Journal Article
2016-01-0542
Hiroshi Kawaguchi, Osamu Funatsumaru, Hiroyoshi Sugawara, Hiroshi Sumiya, Takanobu Iwade, Tomitaka Yamamoto, Takashi Koike, Ryuta Kashio
Abstract Trivalent chromium passivation is used after zinc plating for enhancing corrosion resistance of parts. In the passivating process, the amount of dissolved metal ions (for example zinc and iron) in the passivation solution increases the longer the solution is used. This results in a reduced corrosion resistance at elevated temperatures. Adding a top coat after this process improves the corrosion resistance but has an increased cost. To combat this, we strove to clarify the mechanism of decreased corrosion resistance and to develop a trivalent chromium passivation with a higher corrosion resistance at elevated temperatures. At first, we found that in parts produced from an older solution, the passivation layer has cracks which are not seen in parts from a fresh/new solution. These cracks grow when heated at temperatures over 120 degrees Celsius.
2016-04-05
Journal Article
2016-01-1258
Tatsuya Iida, Hiroya Mitani, Mamoru Sato
Abstract 1 Inside a paint booth to spray paint on vehicle bodies, bumpers, and other parts (hereinafter referred to as “works”), air whose temperature and humidity are controlled by air-conditioner is supplied by blower fans through filters. Dust-eliminated and regulated air flow is sent downward from top to bottom (hereinafter referred to as “downflow”) in the painting booth. Conventionally, paint which does not adhere to work in spraying (hereinafter referred to as “paint mist”) is collected while flowing at a high speed through a slit opening called venturi scrubber in a mixture of air and water. However, this mist collecting system using venturi scrubber requires a large space with a large amount of pressure loss while consuming substantial energy. By radically changing the mist collecting principle, we developed a new compact system with less pressure loss aiming to reduce energy consumption by 40% in a half-size booth.
2016-04-05
Journal Article
2016-01-0543
Takashi Hara, Masaki Kato, Kazuki Mizutani
Abstract There are such outside door handles called smart handles which have a transmitting antenna, a lock/unlock sensor, and a sensor detection circuit, with which operation of door lock is possible just by "touching" the electrostatic-capacitance type sensor of the handles.As the design of the outside handles, body color painting and Cr plating are adopted. However, if plating is applied over the entire surface of a smart handle, electromagnetic waves transmitted from the antenna will be blocked since plating material is electrically conductive. In addition to this, touching a part other than the sensor may change the electrostatic-capacitance of the sensor, which results in unwanted functioning of the lock/unlock sensor. Because of this, only part of the handle, which does not hinder the transmission of electromagnetic waves and does not cause unwanted functioning, is covered by plating, that is called, "Partially plated specifications" (Figure 1).
2016-04-05
Journal Article
2016-01-1344
Koushi Kumagai, Masaaki Kuwahara, Tsuyoshi Yasuki, Norimasa Koreishi
Abstract This paper describes the development of a fracture finite element (FE) model for laser screw welding (LSW) and validation of the model with experimental results. LSW was developed and introduced to production vehicles by Toyota Motor Corporation in 2013. LSW offers superb advantages such as increased productivity and short pitch welding. Although the authors had previously developed fracture FE models for conventional resistance spot welding (RSW), a fracture model for LSW has not been developed. To develop this fracture model, many comprehensive experiments were conducted. The results revealed that LSW had twice as many variations in fracture modes compared to RSW. Moreover, fracture mode bifurcations were also found to result from differences in clearance between welded plates. In order to analyze LSW fracture phenomena, detailed FE models using fine hexahedral elements were developed.
2016-04-05
Journal Article
2016-01-1383
James Jan, Eben Prabhu, Xingfu Chen, Ulrich Weiss
Abstract Air quenching is a common manufacturing process in automotive industry to produce high strength metal component by cooling heated parts rapidly in a short period of time. With the advancement of finite element analysis (FEA) methods, it has been possible to predict thermal residual stress by computer simulation. Previous research has shown that heat transfer coefficient (HTC) for steady air quenching process is time and temperature independent but strongly flow and geometry dependent. These findings lead to the development of enhanced HTC method by performing CFD simulation and extracting HTC information from flow field. The HTC obtained in this fashion is a continuous function over the entire surface. In current part of the research, two patching algorithms are developed to divide entire surface into patches according to HTC profile and each patch is assigned a discrete HTC value.
2016-04-05
Journal Article
2016-01-1560
Bo Lin, Chinedum E. Okwudire
Abstract Ball nut assemblies (BNAs) are used in a variety of applications, e.g., automotive, aerospace and manufacturing, for converting rotary motion to linear motion (or vice versa). In these application areas, accurate characterization of the dynamics of BNAs using low-order models is very useful for performance simulation and analyses. Existing low-order contact load models of BNAs are inadequate, partly because they only consider the axial deformations of the screw and nut. This paper presents a low-order load distribution model for BNAs which considers the axial, torsional and lateral deformations of the screw and nut. The screw and nut are modeled as finite element beams, while Hertzian Contact Theory is used to model the contact condition between the balls and raceways of the screw and nut. The interactions between the forces and displacements of the screw and nut and those at the ball-raceway contact points are established using transformation matrices.
2016-04-05
Journal Article
2016-01-0317
Yuanzhan Wang, Jason B. Siegel, Anna G. Stefanopoulou
Abstract This paper addresses scheduling of quantized power levels (including part load operation and startup/shutdown periods) for a propane powered solid oxide fuel cell (SOFC) hybridized with a lithium-ion battery for a tracked mobile robot. The military requires silent operation and long duration missions, which cannot be met by batteries alone due to low energy density or with combustion engines due to noise. To meet this need we consider an SOFC operated at a few discrete power levels where maximum system efficiency can be achieved. The fuel efficiency decreases during transients and resulting thermal gradients lead to stress and degradation of the stack; therefore switching power levels should be minimized. Excess generated energy is used to charge the battery, but when it’s fully charged the SOFC should be turned off to conserve fuel.
2016-04-05
Journal Article
2016-01-1198
Pascal Schmalen, Peter Plapper, Wayne Cai
Abstract Laser welding of dissimilar metals such as Aluminum and Copper, which is required for Li-ion battery joining, is challenging due to the inevitable formation of the brittle and high electrical-resistant intermetallic compounds. Recent research has shown that by using a novel technology, called laser braze-welding, the Al-Cu intermetallics can be minimized to achieve superior mechanical and electrical joint performance. This paper investigates the robustness of the laser braze-welding process. Three product and process categories, i.e. choice of materials, joint configurations, and process conditions, are studied. It is found that in-process effects such as sample cleanness and shielding gas fluctuations have a minor influence on the process robustness. Furthermore, many pre-process effects, e.g. design changes such as multiple layers or anodized base material can be successfully welded by process adaption.
2016-04-05
Technical Paper
2016-01-0329
Piyush Bubna, Michael P. Humbert, Marc Wiseman, Enrico Manes
Abstract Conventional car manufacturing is extremely capital and energy-intensive. Due to these limitations, major auto manufacturers produce very similar, if not virtually identical, vehicles at very large volumes. This limits potential customization for different users and acts as a barrier to entry for new companies or production techniques. Better understanding of the barriers for low volume production and possible solutions with innovative production techniques is crucial for making low volume vehicles viable and accelerating the adoption of new production techniques and lightweight materials into the competitive marketplace. Additive manufacturing can enable innovative design with minimal capital investment in tooling and hence should be ideal for low and perhaps high volume parts. For this reason, it was desired to evaluate potential opportunities in manufacturing automotive parts with additive techniques.
2016-04-05
Journal Article
2016-01-0982
Philip Lawson, John Houldcroft, Andrew Neil, Andrea Balcombe, Richard Osborne, Antonio Ciriello, Wilhelm Graupner
Abstract A recent trend in powertrain development organisations has been to apply processes historically associated with manufacturing. The aim is to capitalise on the resulting productivity gains to contain the increasing test demand necessary to develop current and future product. Significant obstacles to the implementation of manufacturing derived methods include the lack of clarity of the engineering test requirements and existing working practices in the product development environment. The System Optimisation Approach has been presented in previous work as a potential solution [1]. As an extension, this paper introduces a new concept closely related to the established manufacturing principle of Process Capability (Cp). Application of the resulting method quantifies the test facility’s capability to provide a test result subject to a specified statistical confidence within a certain number of test repeats.
2016-02-01
Technical Paper
2016-28-0069
Praveen Kumar Gupta, Pankaj Maheshwari, Sarita Kumari
Abstract Automotive textile is an integral aspect of technical textile. Seating fabric plays an important part in defining the interior theme in a car cabin which is being perceived by a customer. Aesthetic appeal in a fabric is achieved by interlacing/interlooping of yarns. Monofilament yarns are used to enhance the aesthetic appearance of the fabric for creating high low effect. This study involves the importance of monofilament yarn at fabric and seat trim levels in automotive seating application. Monofilament in fabric imparts aesthetic and strength to the seat trim. Apart from design & engineering evaluation, manufacturing feasibility for evaluation of fabric during stitching process is critical when evaluating fabrics with monofilaments. Main parameters considered are: 1 Importance of monofilament yarn.2 Evaluation criteria for monofilament yarn.3 Performance of monofilament yarn at fabric level & seat trim level.
2016-02-01
Technical Paper
2016-28-0066
Vishad Uttam, Nitin Jain, Kislaya Ravi
Abstract Chrome plated plastic parts are extensively used across the automobile industry. Being exterior parts they are subjected to harsh environmental condition. Washing of vehicle will also make these parts more prone to corrosion. Thus the main aim while deciding chemical composition is to decelerate the process of corrosion. This paper describes the process of corrosion and general chemical composition of the overall layers to inhibit and delay the process of corrosion. An experimental study is done to establish the effect of variation in composition of plating layers.
2016-02-01
Technical Paper
2016-28-0211
Prasad M. Rao, Shailesh S. Kulkarni
Abstract The paper talks about machining techniques and solution approaches while machining Aluminium grade gearbox housings. Mahindra’s next generation gearbox housings are made totally of Aluminium; along with the higher strength to weight ratio that comes with using Aluminium come highly optimized ribbed structures that aid in achieving the said strength. While machining such Aluminium structures, it is imperative that the clamping forces do not load the component in ways it is not intended to. The paper talks about finish machining and proving out a semi-finished gearbox housing set (front, intermediate plate and rear) on a conventional Horizontal Machining Center (HMC). The input to the machine is the semi-finish housing that is already machined before with stock for finish operations.
Viewing 241 to 270 of 8953