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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 Truck platooning comprises a number of trucks equipped with automated lateral and longitudinal vehicle control technology, which allows them to move in tight formation with short following distances. This study is an initial step toward developing an understanding of the occupant injury risks associated with the multiple sequential impacts between truck platoons and roadside safety barriers, regardless of whether the crash is associated with a malfunction of automated control or human operation. Full-scale crash impacts of a tractor-trailer platoon into a concrete bridge guardrail were simulated for a specific Test Level condition according to the Manual for Assessing Safety Hardware (MASH) standards. The model of the bridge barrier was developed based on its drawings, and material properties were assigned according to literature data.

Abstract A number of studies have shown that driving an unfamiliar vehicle has the potential to introduce additional risk, especially for novice drivers. However, such studies have generally used statistical methods based on analyzing crash and near-crash data from a range of driver groups, and therefore the evaluation has the potential to be subjective and limited. For a more objective perspective, this study suggests that it would be worthwhile to consider vehicle dynamic signals obtained from the Controller Area Network (CAN-Bus) and smartphones. This study, therefore, is focused on the effect of driver experience and vehicle familiarity for issues in driver modeling and distraction. Here, a group of 20 drivers participated in our experiment, with 13 of them having participated again after a one-year time lapse in order for analysis of their change in driving performance.

Abstract Lane changes are stressful maneuvers for drivers, particularly during high-speed traffic flows. However, modeling driver’s lane-changing decision and implementation process is challenging due to the complexity and uncertainty of driving behaviors. To address this issue, this article presents a personalized Lane-Changing Model (LCM) for Advanced Driver Assistance System (ADAS) based on deep learning method. The LCM contains three major computational components. Firstly, with abundant inputs of Root Residual Network (Root-ResNet), LCM is able to exploit more local information from the front view video data. Secondly, the LCM has an ability of learning the global spatial-temporal information via Temporal Modeling Blocks (TMBs). Finally, a two-layer Long Short-Term Memory (LSTM) network is used to learn video contextual features combined with lane boundary based distance features in lane change events.

Abstract Carbon fiber reinforced plastic (CFRP) has been used in automobiles as well as airplanes. Because of its light weight and high strength, CFRP is a good choice for making vehicle bodies lighter, which would improve fuel economy. Conventional metal bodies provide a convenient body return for electric wiring and offer good shielding against electromagnetic fields. Although CFRP is a conductor, its conductivity is much lower than that of metals. Therefore, CFRP bodies are usually not useful for electric wiring. In thunderstorms, an automotive body is considered to be a Faraday cage that protects the vehicle’s occupants from the potential harms of lightning. Before CFRP becomes widely applied to automotive bodies, its electric and electromagnetic properties need to be investigated in order to determine whether it also works as a Faraday cage against lightning. In this article, CFRP and metal body vehicles were tested under artificial lightning.

Abstract Introduction: This study evaluates driving ability in those with Charcot Marie Tooth Disease Type 1A, a hereditary peripheral neuropathy. Methods: Individuals with Charcot Marie Tooth Disease Type 1A (n = 18, age = 42 ± 7) and controls (n = 19; age = 35 ± 10) were evaluated in a driving simulator. The Charcot Marie Tooth Neuropathy Score version 2 was obtained for individuals. Rank Sum test and Spearman rank correlations were used for statistical analysis. Results: A 74% higher rate of lane departures and an 89% higher rate of lane deviations were seen in those with Charcot Marie Tooth Disease Type 1A than for controls (p = 0.005 and p < 0.001, respectively). Lane control variability was 10% higher for the individual group and correlated with the neuropathy score (rS = 0.518, p = 0.040), specifically sensory loss (rS = 0.710, p = 0.002) and pinprick sensation loss in the leg (rS = 0.490, p = 0.054).

Abstract In recent years, several buses have ignited in some cities in China, causing numerous deaths and significant property damage. However, few research studies have been conducted to deal with such accidents. Therefore, in this work, a linear-shaped charge jet with rectangular cross sections was used to hew out evacuation routes for burning buses, and the parameter design for the shaped charge jet was improved according to asymmetry limitations and human tolerance. A numerical finite element simulation model of the behavior of a jet penetrating the jambs was established using ANSYS/LS-DYNA software. The asymmetrical characteristics of an arc segment in the structure of a rectangular-shaped charge were analyzed, in addition to the influence on the deviations of the jet penetration capacity and blast injuries to occupants caused by the side effects of detonation.

Abstract This study aims to take the first step in bridging the gap between vehicle dynamics systems and autonomous control strategies research. More specifically, a nested method is employed to evaluate the collision avoidance ability of autonomous vehicles in the primary design stage theoretically based on both dynamics and control parameters. An integrated model is derived from a half car mathematical model in the lateral direction, consisting of two degrees of freedom, lateral deviation and yaw angle, with a traction mathematical model in the longitudinal direction, consisting of two degrees of freedom, the longitudinal velocity and rolling velocity of the wheel. The integrated model uses a mathematical power train model to generate the torque on the wheel and connects the two systems via the magic formula tyre model to represent the tyre non-linearity during augmented longitudinal and lateral dynamic attitudes.

Abstract The vehicle attributes developed for emerging markets like India are unique because of different topographical conditions, diversity and culture within the different states. Major attributes in vehicle development process is development of safe and sustainable vehicle systems (steering, brakes etc.) for the driver. India is presently an emerging market for automotive sector. With booming economy, purchasing power of the consumer has gone up in the past few years. Most of young population of India have started buying the cars. At the same time, India’s road infrastructure, vehicle regulations have exalted over the years. The consumer cognizance towards the vehicles have started changing now. They want safer, robust system in their vehicles with new convenience features at affordable cost. In recent years, almost all OEM’s in India have migrated steering systems from HPAS to EPAS for payback on fuel economy and weight.

Abstract The mechanical efficiency of the current continuously variable transmission (CVT) suffers from high pump loss induced by a high-pressure system. A novel wedge mechanism is designed into the CVT clamp actuation system to generate the majority of clamp force mechanically. Therefore, the hydraulic system can operate at a low-pressure level most of the time, and the pump loss is greatly reduced to improve the CVT’s mechanical efficiency. Through dynamic analysis and design optimization, 90% of clamp force is contributed by the wedge mechanism and the rest of the 10% is generated by a conventional hydraulic system. The optimal design is validated through dynamic modeling using Siemens Virtual.Lab software by simulating the wedge clamp force generation, ratio change dynamics, and system response under tip-in conditions. After that, we built prototype components that target 70% of the clamp force contributed by the wedge mechanism and tested them on a transmission dynamometer.

Abstract Gasoline particulate filters (GPFs) are important aftertreatment components that enable gasoline direct injection (GDI) engines to meet European Union (EU) 6 and China 6 particulate number emissions regulations for nonvolatile particles greater than 23 nm in diameter. GPFs are rapidly becoming an integral part of the modern GDI aftertreatment system. The Active Exhaust Tuning (EXTUN) Valve is a butterfly valve placed in the tailpipe of an exhaust system that can be electronically positioned to control exhaust noise levels (decibels) under various vehicle operating conditions. This device is positioned downstream of the GPF, and variations in the tuning valve position can impact exhaust backpressures, making it difficult to monitor soot/ash accumulation or detect damage/removal of the GPF substrate. The purpose of this work is to present a unique example of subsystem control and diagnostic architecture for an exhaust system combining GPF and EXTUN.

Abstract The transient surface pressure over a full-scale, operational compact automotive vehicle—a Volkswagen Golf 7—exposed to transient crosswinds with relative yaw angles of β = 22-45° has been characterized. Experiments were performed at the BMW side-wind facility in Aschheim, Germany. Measurements of the incoming flow in front of the car were taken with eleven five-hole dynamic pressure probes, and separately, time-resolved surface pressure measurements at 188 locations were performed. Unsteady characteristics (not able to be identified in quasi-steady modelling) have been identified: the flow in separated regions on the vehicle’s leeward side takes longer to develop than at the windward side, and spatially, the vehicle experiences local crosswind as it gradually enters the crosswind.

Abstract Obstacle avoidance is an important function in self-driving vehicle control. When the vehicle move from any arbitrary start positions to any target positions in environment, a proper path must avoid both static obstacles and moving obstacles of arbitrary shape. There are many possible scenarios, manually tackling all possible cases will likely yield a too simplistic policy. In this paper reinforcement learning is applied to the problem to form effective strategies. There are two major challenges that make self-driving vehicle different from other robotic tasks. Firstly, in order to control the vehicle precisely, the action space must be continuous which can’t be dealt with by traditional Q-learning. Secondly, self-driving vehicle must satisfy various constraints including vehicle dynamics constraints and traffic rules constraints. Three contributions are made in this paper.

Abstract Potential collisions with oncoming traffic while turning left belong to the most safety-critical situations accounting for ~25% of all intersection crossing path crashes. A Left Turn Assist (LTA) was developed to reduce the number of crashes. Crucial for the effectiveness of the system is the design of the human-machine interface (HMI), i.e. defining how the system uses the calculated crash probability in the communication with the driver. A driving simulator study was conducted evaluating a warning strategy for two use cases: firstly, the driver comes to a stop before turning (STOP), and secondly, the driver moves on without stopping (MOVE). Forty drivers drove through three STOP and two MOVE scenarios. For the STOP scenarios, the study compared the effectiveness of an audio-visual warning with an additional brake intervention and a baseline. For the MOVE scenarios, the study analyzed the effectiveness of the audio-visual warning against a baseline.

Abstract Estimating the power demand of a steering system is one of the main tasks during steering system development in the concept phase of a vehicle development process. Most critical for typical axle kinematics are parking maneuvers with simultaneously high rack forces and velocities. Therefore, the focus of the article is a tire model for standstill, which can be parametrized without measurements, only having tire dimensions and conditions (inflation pressure and wheel load) as input. Combined with a double-track model, a vehicle model is developed, which is able to predict the rack force and is fully applicable during the concept phase. The article demonstrates quantitatively that the tie rod forces, and thereby especially the tire bore torque, cause the largest fraction of the power demand at the rack. For this reason, the prediction of the bore torque is investigated in detail, whereby basic approaches from the literature are analyzed and enhanced.

Abstract This article presents a fault diagnosis approach for roller bearing by applying the autocorrelation approach to filtered vibration measured signal. An optimal Morlet wavelet filter is applied to eliminate the frequency associated with interferential vibrations; the raw measured signal is filtered with a band-pass filter based on a Morlet wavelet function whose parameters are optimized based on maximum Kurtosis. Autocorrelation enhancement is applied to the filtered signal to further reduce the residual in-band noise and highlight the periodic impulsive feature. The proposed technique is used to analyze the experimental measured signal of investigated vehicle gearbox. An artificial fault is introduced in vehicle gearbox bearing an orthogonal placed groove on the inner race with the initial width of 0.6 mm approximately. The faulted bearing is a roller bearing located on the gearbox input shaft - on the clutch side.

Abstract Rolling-resistance is leading the direction of numerous tire developments due to its significant effect on fuel consumption and CO2 emissions considering the vehicles in use globally. Many attempts were made to reduce rolling-resistance in vehicles, but with no or limited success due to tire complexity and trade-offs. This article investigates the concept of multiple chambers inside the tire as a potential alternative solution for reducing rolling-resistance. To accomplish that, novel multi-chamber designs were introduced and numerically simulated through finite-element (FE) modeling. The FE models were compared against a standard design as the baseline. The influences on rolling-resistance, grip, cornering, and mechanical comfort were studied. The multi-chambers tire model reduced rolling-resistance considerably with acceptable trade-offs. Independent air volumes isolating tread from sidewalls would maintain tire’s profile effectively.

Abstract To reduce fuel consumption and carbon dioxide (CO2) emissions from mobile air conditioning (A/C) systems, “U.S. Light-Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards” identified solar/thermal technologies such as solar control glazings, solar reflective paint, and active and passive cabin ventilation in an off-cycle credit menu. National Renewable Energy Laboratory (NREL) researchers developed a sophisticated analysis process to calculate U.S. light-duty A/C fuel use that was used to assess the impact of these technologies, leveraging thermal and vehicle simulation analysis tools developed under previous U.S. Department of Energy projects. Representative U.S. light-duty driving behaviors and weighting factors including time-of-day of travel, trip duration, and time between trips were characterized and integrated into the analysis.

Abstract ISO 26262 needs to be considered when developing safety-relevant E/E systems within the automotive industry. One part of the development process according to ISO 26262 is the derivation of the safety requirements for component functions. Here, one attribute of the safety requirements is the Automotive Safety Integrity Level (ASIL). The ASIL at a component level can be determined using ASIL allocation and decomposition. Considering complex systems such as vehicle electrical systems, countless possibilities can be identified for how the ASILs at a component level can be assigned in line with safety goals. In terms of efficiency, manual assignment is not expedient. Therefore, an algorithm for automated assignment of the ASILs will be introduced which considers constraints based on a fault tree analysis. The function of the approach will be demonstrated using the example of a vehicle electrical system from an automated vehicle.

Abstract Tire-pavement interaction noise (TPIN) dominates for passenger cars above 40 km/h and trucks above 70 km/h. Numerous studies have attempted to uncover and distinguish the basic mechanisms of TPIN. However, intense debate is still ongoing about the validity of these mechanisms. In this work, the physical mechanisms proposed in the literature were reviewed and divided into three categories: generation mechanisms, amplification mechanisms, and attenuation mechanisms. The purpose of this article is to gather the published general opinions for further open discussions.