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Abstract The project of lean management is implemented in General Motors India Private Limited, Pune, India plant. The aim of the project is to improve manpower utilization by removing seven types of wastes using lean management system in kitting process. Lean manufacturing or management is the soul of Just-In-Time philosophy and is not new in Automobile manufacture sector where it born. Kitting area is analogs to the modern supermarket where required components, parts, consumables, subassemblies are kept in bins. These bins are placed in racks so that choosing right part at right time can be achieved easily. Video recording, in-person observation, feedback from online operators and other departments such as maintenance, control, supply chain etc. are taken. It is observed that the work content performed by current strength of operators can be performed by less number of operators. After executing this project, it was possible to reduce one operator and increase manpower utilization.

Abstract Geometric variation stemming from manufacturing can be a limiting factor for the quality and reliability of products. Therefore, manufacturing assessments are increasingly being performed during the early stages of product development. In the aerospace industry, products are complex engineering systems, the development of which require multidisciplinary expertise. In such contexts, there are significant barriers against assessing the effects of geometric variation on the functionality of products. To overcome these barriers, this article introduces a new methodology consisting of a modelling approach linked to a multidisciplinary simulation environment. The modelling approach is based on the parametric point method, which allows point-scanned data to be transferred to parameterised CAD models. In a case study, the methodology is implemented in an industrial setting.

Abstract With highway vehicles using over 20% of the total energy consumption in the United States, making strides in improving their fuel economy will positively influence the nation’s environmental impact. One methodology to accomplish this outcome is by reducing vehicle weight. In this regard, since the internal combustion (IC) engine is a major contributor to the mass of an automobile, it is an ideal area to target. Prior efforts in this area include using alternative materials (e.g., aluminum or magnesium) to decrease weight. Here, additive manufacturing (AM) is an appealing option due to its freedom from typical manufacturing constraints and the ability to produce highly optimized designs using nonconventional powertrain materials (e.g., titanium). The use of AM has the potential to increase reliability, improve performance, decrease production cost, and possibly minimize the number of parts.

Abstract Single point incremental forming (SPIF) is a sheet forming technology giving low volume production with high flexibility characteristics. The flexibility of the process is mainly related to the fact that incremental forming does not require a dedicated die to operate as compared to other forming processes. Polymers are extensively used for many applications because of their good mechanical properties. Considerable research has been reported for the SPIF of metals, but the researches on polymers are in scarce. In the present work, SPIF is performed on one of the polymers known as polyvinyl chloride. The effect of wall angle, feed rate, and step size on springback, thinning, and surface roughness is observed. It was found that the springback mainly depends on the wall angle but it is least dependent on the feed rate. The thinning and the surface roughness also mainly depend on the wall angle but are least dependent on step size.

Abstract Climate change has necessitated the development of “green” alternatives to replace existing materials. This focus has resulted in the push toward fabricating natural fiber-reinforced polymer composites. This research work looks at the surface roughness (SR) of natural fibers like rice husk ash (RHA) and groundnut shell ash (GSA) reinforced in nine different concentrations into an epoxy matrix to form composites. Composite samples are fabricated using various concentrations of natural fibers and measures and optimizes for the SR through the implementation of genetic algorithms (GA). It was found that a minimum SR of 1.422 μm can be obtained for an epoxy/hardener ratio of 3:1 and without the addition of any reinforcements. This optimization was achieved within 102 generations. In addition to GA optimization, another optimization implementation was done through the Taguchi method.

Abstract Welding is a dominant joining process employed in fabrication industries, especially in critical areas such as boiler, pressure vessels, and marine structure manufacturing. Online monitoring of welding processes using sensors and intelligent models is increasingly used in industries for predicting weld conditions. Studies are conducted in a Shielded Metal Arc Welding (SMAW) process using sound, current, and voltage sensors to predict the weld conditions. Sensor signatures are acquired from the good weld and defective weld conditions established in this study. Signal processing is carried out, and time-domain statistical features are extracted. Statistical features are also extracted from the power waveform derived from the current and voltage data for all the weld conditions. Classification And Regression Tree (CART) and Support Vector Machine (SVM) algorithms are used to build the statistical models to predict the weld conditions.

Abstract The dimensional quality of the car body is built on quality management of form, fitment, and functional requirements. Each of these attributes reflects the final product quality and, therefore, needs to be ascertained quantitatively. Design intent and functionality conformance with specifications are paramount to performance, and thus quality. It is accomplished through optimal Geometric Dimensioning and Tolerancing of parts (GD&T), datum/Primary Locating Points (PLP) strategy, tricks/levers, and assembly design. Challenges stem from the complexity involved in the datum layout strategy and its optimization for desired deviations. Incorrect datum schemes in design prompt underconstrained fixtures, redundant datum, the sensitivity of datum layout, etc. and induce defects in later stages. The end effect is smoothing out the variation issues leading to compromise in quality.

Abstract Internal combustion (IC) engines are widely used in automotive, marine, agricultural and industrial machineries because of their superior performance, high efficiency, power density, durability and versatility in size and power outputs. In response to the demand for improved engine efficiency and lower CO2 emissions, advanced combustion process control techniques and more renewable fuels should be adopted for IC engines. Lean-burn combustion is one of the technologies with the potential to improve thermal efficiencies due to reduced heat loss and higher ratio of the specific heats. In order to operate the IC engines with very lean air/fuel mixtures, multiple turbulent jet pre-chamber ignition has been researched and developed to extend the lean-burn limit. Turbulent Jet Ignition (TJI) offers very fast burn rates compared to spark plug ignition by producing multiple ignition sites that consume the main charge rapidly.

Abstract Fatigue performance can be a critical attribute for the production of structural parts or components via additive manufacturing (AM). In comparison to the static tensile behavior of AM components, there is a lack of knowledge regarding the fatigue performance. The growing market demand for AM implies the need for more accurate fatigue investigations to account for dynamically loaded applications. A357.0 parts are processed by laser-based powder bed fusion (L-PBF) in order to evaluate the effect of surface finishing on fatigue behavior. The specimens are surface finished by shot peening using ϕ = 0.2 and ϕ = 0.4 mm steel particles and ϕ = 0.21-0.3 mm zirconia-based ceramic particles.

Corrigendum - The word "Differ" in the title should be corrected to "Different". The correct title is: Rapid Methodology to Simultaneous Quantification of Different Antioxidants in Biodiesel Using Infrared Spectrometry and Multivariate Calibration.

Abstract The aim of this work is to quantify three different antioxidants in biodiesel - Santoflex, baynox, and tocopherol-using Middle Infrared (MIR) spectroscopy and chemometrics. For the construction of the models, 28 samples containing an antioxidant in the range of 0.1 to 500 mg/kg in biodiesel were used. We developed three models based on PLS 1 multivariate calibration method to quantify each of the three antioxidants separately and a model based on PLS 2 method to quantify simultaneously all the antioxidants. All models were compared to the values of root mean square error of calibration (RMSEC) and validation (RMSEP). For the baynox, santoflex, and tocopherol antioxidants quantification using PLS 1, the values of RMSEC and RMSEP were 37.2, 18.8, 9.0 mg/kg, and 26.7, 21.1, 68.6 mg/kg, respectively.

Abstract Door-closing sound quality is a very important noise, vibration, and harshness (NVH) attribute since it may have a significant impact on customers’ perception, recognition, and luxury sensation of an automobile brand. Therefore, its evaluation methodology and design process have been one of the research and engineering efforts for all NVH organizations in the automotive industry. In many cases, the resolution of a door-closing sound quality issue lacks a systematic approach, and engineers rush to work when an issue surfaces. While subjective evaluation may easily find a door-closing sound problem, it oftentimes cannot directly pinpoint and go right to the root cause of the issues. In many cases, engineers could only guesstimate the possible relevant structural components based on past experiences. In this work, a door-closing sound quality development process, which has already been implemented in vehicle programs, is summarized and presented.

Abstract The need for high efficiency automotive engines has led to more complex air handling and fuel injection systems, higher compression ratios, more advanced combustion and aftertreatment systems, and the use of fuels with higher octane ratings. Higher octane fuels have a lower propensity to knock. This work studies the influence of changing fuel octane rating on two modern production gasoline vehicles, one with a naturally aspirated, port injected engine and the other with a turbocharged, direct injected engine, using fuels with four different octane number grades (with 85, 87, 91, and 93 anti-knock indices) and operated over a variety of driving cycles and temperature conditions. Unlike previous studies, this effort develops and demonstrates a methodology that isolates fuel effects on fuel consumption and provides a clear view of the octane impact on existing vehicles.

Abstract The manufacturing of diesel injector nozzles requires precision processing to produce multiple micro-holes. An abrasive fluid containing a mixture of mineral oil and hard particles is used for rounding them, ensuring the hydrodynamics of the injection. As verified in a previous investigation, the viscosity of the fluid undergoes uncontrolled changes during hydro-erosive (HE) grinding. Such undesired viscosity changes are detrimental to the process and difficult to assess. The current investigation aims to study the possibility of using the refractive index of the oils used in the HE grinding for assessing their viscosities. A calibration curve correlating the refractive index and viscosity was obtained from the analysis of samples produced by mixing two distinct mineral oils in different proportions. The determined calibration curve was tested with 45 samples of filtered oil, collected directly from the tanks during the HE grinding.

Abstract Decision analysis (DA), a well-established discipline in business and engineering, is entering another domain of application due to the advent of Industry 4.0. DA enables optimal decisions by finding system parameters that maximize the utility, or in the presence of uncertainty the expected utility, from the attributes of a system. Whether there is a single decision maker or all decision makers have uniform preferences, determining risk behavior and the resulting utility is well developed in the existing literature. However, variability in preferences has not been satisfactorily addressed. This gap gains added significance in the face of the demands of Industry 4.0 where cyberphysical production systems must drive autonomous decision-making on the factory floor. The decisions must accommodate a distribution of customer and designer preferences, including production auditors within the organization.

Abstract To protect ship equipment of river and sea transport, it is suggested to use polymeric protective coatings based on epoxy diane oligomer ED-20, polyethylene polyamine (PEPA) curing agent and filler, which is a departure from industrial production. Thus the purpose of the work is analysis of major dependency of the properties on the content of fillers that allowed to revealed the critical filler content (furnace black) in composites to form a protective coating with the required set of characteristics. The infrared (IR) spectral analysis was used to investigate the presence of bonds on the surface of particles of the PM-75 furnace black, which allows us to assess the degree of cross-linking of the polymer. The influence of the content of dispersed furnace black on the physicomechanical and thermophysical properties and the structure of the protective coating is investigated.

Abstract Electrolytic hydrogen production equipment has numerous hydrogen pipelines and high-pressure hydrogen storage tanks which may leak hydrogen which can lead to explosions causing damage to the nearby personnel and equipment. The present work modeled hydrogen explosions in a skid-mounted electrolytic hydrogen production unit. The model was first used to predict the area affected by an explosion without protective walls. The effects of protective walls on the flame and overpressure were then studied by modeling explosions with various protective walls at various distances from the opening on the side of the unit. The results show that the protective walls effectively reduced the damage behind the wall. However, the reflected shock waves may cause secondary damage in front of the wall if the protective wall is too close to the opening. Moreover, the protective wall blocks the hydrogen diffusion which increases the flammable gas mass.

Abstract Many consider hydrogen to be the automobile fuel of the future. Indeed, it has numerous characteristics that makes it very attractive. Hydrogen has a much higher energy density than gasoline, can be produced from water, and its only emission is water. However, there are numerous challenges associated with hydrogen. In particular, the production of hydrogen is a key issue. Currently, most hydrogen is developed from methane, resulting in hydrogen having a carbon footprint. New investments into electrolysis from renewable energy sources is showing promise as an alternative for generating hydrogen. Further, the distribution of hydrogen poses many problems, requiring substantial infrastructure to support a hydrogen economy. Additionally, hydrogen storage is a key issue since most conventional storage mechanisms are overly bulky. If these three issues can be addressed, hydrogen is posed for being a key fuel as the world tries to move away from fossil fuels.

Abstract While new materials are introduced in the automotive industry regularly, there seems to be a lack of generalized frameworks for how to do this efficiently and effectively. Multiple studies have been published on material substitution in a specific component, but the applicability of these to other projects are unclear. Therefore, the authors propose a generalized framework for introduction of new materials in existing production systems in this article. In a study based on three cases in the Swedish automotive industry, the authors have found generalizable insights on challenges and opportunities when introducing new materials that could be converted into a framework for introduction of new materials in the automotive industry. This framework contains both organizational and technological aspects of new material introduction, and is built chronologically from the start of a material strategy framework formulation to the start of a material introduction project.

Abstract Additive manufacturing (AM) technologies can produce lighter parts; reduce manual assembly processes; reduce the number of production steps; shorten the production cycle; significantly reduce material consumption; enable the production of prostheses, implants, and artificial organs; and produce end-user products since it is used in many sectors for many reasons; it has also started to be used widely, especially in the field of aerospace. In this study, polylactic acid (PLA) was preferred for the antenna substrate because it is environmentally friendly, easy to recycle, provides convenience in production design with a three-dimensional (3D) printer, and is less expensive compared to other available materials. Copper (Cu) tape and graphene filament were employed for the antenna patch component due to their benefits.