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The design of lightweight vehicle structures has become a common method for automotive manufacturers to increase fuel efficiency and decrease carbon emission of their products. By using aluminum instead of steel, manufacturers can reduce the weight of a vehicle while still maintaining the required strength and stiffness. Currently, Resistance Spot Welding (RSW) is used extensively to join steel body panels but presents challenges when applied to aluminum. When compared to steel, RSW of aluminum requires frequent electrode cleaning, higher energy usage, and more controlled welding parameters, which has driven up the cost of manufacturing. Due to the increased cost associated with RSW of aluminum, Refill Friction Stir Spot Welding (RFSSW) is being considered as an alternative to RSW for joining aluminum body panels. RFSSW consumes less energy, requires less maintenance, and produces more consistent welding in aluminum as compared to RSW.

Gouges and scratches to rollover protection structures are informative to the reconstruction and analysis of real-world vehicle rollover crashes. Variations in ground surface composition can be correlated with accompanying witness marks on the vehicle rollover protection structure. This paper presents the results of rollover protection structure specimen tests using a variety of test speeds and surface compositions. The test results and analyses that follow are displayed for use in comparison to similar damage on subject crash vehicles. In addition, impact of steel rollover protection structures with various opposing ground surface materials can produce visible sparks in low light conditions. Tests were performed to show the ability of these structures to produce sparks from various surface impacts.

This paper outlines the history and background of the NLGI (formerly known as the National Lubricating Grease Institute) lubricating grease specifications, GC-LB classification of Automotive Service Greases as well as details on the development of new requirements for their High-Performance Multiuse (HPM) grease certification program. The performance of commercial lubricating grease formulations through NLGI's Certification Mark using the GC-LB Classification system and the recently introduced HPM grease certification program will be discussed. These certification programs have provided an internationally recognized specification for lubricating grease and automotive manufacturers, users and consumers since 1989. Although originally conceived as a specification for greases for the re-lubrication of automotive chassis and wheel bearings, GC-LB is today recognized as a mark of quality for a variety of different applications.

1Increasing adoption of downsized, boosted, spark-ignition engines has improved vehicle fuel economy, and continued improvement is desirable to reduce carbon emissions in the near-term. However, this strategy is limited by damaging preignition events which can cause hardware failure. Research to date has shed light on various contributing factors related to fuel and lubricant properties as well as calibration strategies, but the causal factors behind an individual preignition cycle remain elusive. If actionable precursors could be identified, mitigation through active control strategies would be possible. This paper uses artificial neural networks to search for identifiable precursors in the cylinder pressure data from a large real-world data set containing many preignition cycles. It is found that while follow-up preignition cycles in clusters can be readily predicted, the initial preignition cycle is not predictable based on features of the cylinder pressure.

In this work, a novel bearing test rig was used to evaluate the impact of oil viscoelasticity on friction torque and oil film thickness in a hydrodynamic journal bearing. The test rig used an electric motor to rotate a test journal, while a hydraulic actuator applied radial load to the connecting rod bearing. Lubrication of the journal bearing was accomplished via a series of axial and radial drillings in the test shaft and journal, replicating oil delivery in a conventional engine crankshaft. Journal bearing inserts from a commercial, medium duty diesel engine (Cummins ISB) were used. Oil film thickness was measured using high precision eddy current sensors. Oil film thickness measurements were taken at two locations, allowing for calculation of minimum oil film thickness. A high-precision, in-line torque meter was used to measure friction torque. Four test oils were prepared and evaluated.

With the developments of Industry 4.0, data analytics solutions and their applications have become more prevalent in the manufacturing industry. Currently, the typical software architecture supporting these solutions is modular, using separate software for data collection, storage, analytics, and visualization. The integration and maintenance of such a solution requires the expertise of an information technology team, making implementation more challenging for small manufacturing enterprises. To allow small manufacturing enterprises to feasibly obtain the benefits of Industry 4.0 data analytics, a full-stack data analytics framework is presented, and its performance evaluated as applied in the common industrial analytics scenario of predictive maintenance. The predictive maintenance approach was achieved by using a full-stack data analytics framework comprised of the PTC Inc. Thingworx software suite.

With the growth of Industry 4.0 in recent years, Augmented Reality (AR) technologies are changing the way operators work by increasing their efficiency and operational performance. A common use of AR is providing operators helpful work instructions for assembly by presenting relevant digital information in the context of the physical environment. These AR experiences can be viewed via several devices such as mobile, wearable, and stationary devices, each being useful for different applications. While in the experience, instructions are provided by means of 3D animation, text, images, and interactive buttons, all of which are directly overlaid onto the physical product or equipment being worked on. This work presents a closed-loop, enterprise connected, AR system for post end Printed Circuit Board (PCB) assembly work instructions.

As automotive designs add more aluminum to lightweight their vehicles, friction stir welding (FSW) will likely become a principal joining process in the industry. FSW is a solid-state joining process which avoids many of the traditional problems of welding aluminum alloys such as hot cracking, porosity and solidification shrinkage. These attributes enable high preforming friction stir welded joints of cast, 5XXX, 6XXX, 7XXX or mixed aluminum alloy combinations. Although FSW technologies have advanced to support high volume applications and have been applied in current automotive parts, its inability for nondestructive evaluation (NDE) increases the cost to manufacture friction stir welded parts. Current state of the art NDE methods for FSW are either ultrasound or radiographic technologies which add complexity to manufacturing lines and additional costs to FSW production. Many have researched ways to reduce NDE costs by using measured forces of the FSW process.

The concept of a seat with an active adjustable seatback stiffness for enhanced safety during a rear impact was published previously. Static testing of a demonstrative prototype is supplemented with repeated dynamic tests at various velocity / acceleration levels. These tests were performed with a Hybrid III Anthropomorphic Test Device (ATD) and demonstrate that the occupant response can be modified by engagement of the device based on the severity of the crash pulse and other factors. A mathematical model for the dynamic response of the seat and the correlated occupant response is in development. Refinement of this technology is complemented by results of the dynamic testing.

Development of a seat with an active adjustable seatback stiffness for enhanced safety during a rear impact is demonstrated. Review of literature suggests that there is not a single value for seatback stiffness to optimize occupant protection. An automobile seat whose stiffness can be actively adjusted based on EDR input and other factors can potentially enhance occupant safety during some rear impact crashes. Static pull tests were performed using a prototype seat demonstrating how seatback stiffness can be modified, and deformation limited, using electromechanical means. Research and development of this technology is ongoing.

Wet clutch friction performance has historically been visualized by multiple graphs due to the number of temperatures and pressures required to characterize the system. However, this same friction performance can be visualized by a single graph using an alternative approach to map the friction data. Applying a method similar to that used to develop the Stribeck curve for journal bearings, a single system-level graph for wet clutches can be created. This paper will highlight how this visualization method, particularly when used to diagnose clutch failures, provides benefits in understanding the effects of both the friction material and the lubricant performance. We conducted extensive studies comparing ideal clutch systems with failed ones under a variety of conditions. Lubricant and friction material failures were independently studied, and durability tests were conducted to evaluate component failures.

A major barrier, preventing RFSSW from use by manufacturers, is the long cycle time that has been historically associated with making a weld. In order for RFSSW to become a readily implementable welding solution, cycle times must be reduced to an acceptable level, similar to that of well developed, competing spot joining processes. In the present work, an investigation of the RFSSW process is conducted to evaluate factors that have traditionally prevented the process from achieving fast cycle times. Within this investigation, the relationship between cycle time and joint quality is explored, as is the meaning and measurement of cycle time in the RFSSW process. Claims and general sentiment found in prior literature are challenged regarding the potential for high-speed RFSSW joints to be made.

The Hot Tube Test is a bench test commonly used by OEMs, Oil Marketers and Lubricant Additive manufacturers within the Small Engines industry. The test uses a glass tube heated in an aluminum block to gauge the degree of lacquer formation when a lubricant is subjected to high temperatures. This test was first published by engineers at Komatsu Ltd. (hence KHT) in 1984 to predict lubricant effects on diesel engine scuffing in response to a field issue where bulldozers were suffering from piston scuffing failures [1]. Nearly 35 years after its development the KHT is still widely used to screen lubricant performance in motorcycle, power tool and recreational marine applications as a predictor of high-temperature piston cleanliness - a far cry from the original intended performance predictor of the test. In this paper we set out to highlight the shortcomings of the KHT as well as to identify areas where it may still be a useful screening tool as it pertains to motorcycle applications.

In the last decade, numerous studies have been conducted to investigate the mechanism of Low Speed Pre-Ignition (LSPI) in Turbocharged Gasoline Direct Injection (TGDi) engines. According to technical reports, engine oil formulations can significantly influence the occurrence of LSPI particularly when higher levels of calcium-based additives are used, increasing the tendency for LSPI events to occur. While most of the studies conducted to date utilized engine tests, this paper evaluates the effect of engine oil formulations on LSPI under real-world driving conditions, so that not only the oil is naturally aged within an oil change interval, but also the vehicle is aged through total test distance of 160,000 km. Three engine oil formulations were prepared, and each tested in three vehicles leading to an identical fleet totaling nine vehicles, all of which were equipped with the same TGDi engine.

Increasingly stringent vehicle emissions legislation is being introduced throughout the world, regulating the allowed levels of particulate matter emitted from vehicle tailpipes. The regulation may prove challenging for gasoline vehicles equipped with modern gasoline direct injection (GDI) technology, owing to their increased levels of particulate matter production. It is expected that gasoline particulate filters (GPFs) will soon be fitted to most vehicles sold in China and Europe, allowing for carbonaceous particulate matter to be effectively captured. However, GPFs will also capture and accumulate non-combustible inorganic ash within them, mainly derived from engine oil. Studies exist to demonstrate the impact of such ash on GPF and vehicle performance, but these commonly make use of accelerated ash loading methods, which themselves introduce significant variation.

Motorcycle OEMs faced with stringent global fuel economy and emission regulations are being forced to develop new hardware and emissions control technologies to remain compliant. Motorcycle oils have become an enabling technology for the development of smaller, more efficient engines operating at higher power density. Many OEMs have therefore become reliant on lubricants to not only provide enhanced durability under more extreme operating conditions, but to also provide fuel economy benefits through reduced energy losses. Unlike passenger car oils that only lubricate the engine, motorcycle oils must lubricate both the engine and the drive train. These additional requirements place different performance demands versus a crankcase lubricant. The drive train includes highly loaded gears that are exposed to high pressures, in turn requiring higher levels of oil film strength and antiwear system durability.

Due to the limitations on resistance spot welding of ultra-thin steel sheet (thicknesses below 0.5 mm) in high-volume automotive manufacturing, a comparison of friction stir spot welding and self-piercing riveting was performed to determine which process may be more amenable to enabling assembly of ultra-thin steel sheet. Statistical comparisons between mechanical properties of lap-shear tensile and T-peel were made in sheet thickness below 0.5 mm and for dissimilar thickness combinations. An evaluation of energy to fracture, fracture mechanisms, and joint consistency is presented.

Downsized gasoline engines, coupled with gasoline direct injection (GDI) and turbocharging, have provided an effective means to meet both emissions standards and customers’ drivability expectations. As a result, these engines have become more and more common in the passenger vehicle marketplace over the past 10 years. To maximize fuel economy, these engines are commonly calibrated to operate at low speeds and high engine loads – well into the traditional ‘knock-limited’ region. Advanced engine controls and GDI have effectively suppressed knock and allowed the engines to operate in this high efficiency region more often than was historically possible. Unfortunately, many of these downsized, boosted engines have experienced a different type of uncontrolled combustion. This combustion occurs when the engine is operating under high load and low speed conditions and has been named Low Speed Pre-Ignition (LSPI). LSPI has shown to be very damaging to engine hardware.

Increasingly stringent fuel economy and emissions regulations around the world have forced the further optimization of nearly all vehicle systems. Many technologies exist to improve fuel economy; however, only a smaller sub-set are commercially feasible due to the cost of implementation. One system that can provide a small but significant improvement in fuel economy is the lubrication system of an internal combustion engine. Benefits in fuel economy may be realized by the reduction of engine oil viscosity and the addition of friction modifying additives. In both cases, advanced engine oils allow for a reduction of engine friction. Because of differences in engine design and architecture, some engines respond more to changes in oil viscosity or friction modification than others. For example, an engine that is designed for an SAE 0W-16 oil may experience an increase in fuel economy if an SAE 0W-8 is used.

This report describes the aircraft designed and built by the Brigham Young University Idaho (BYU-Idaho) Aero Design Team. The aircraft was built for the SAE Aero East Competition 2017 hosted in Lakeland, Florida. The objective is to design an all-electric aircraft optimized to carry as much weight as possible, while also minimizing the empty weight of the aircraft capable of successfully completing a flight circuit. A flight circuit is defined as flying completely around two safety cones for a total distance of about 726ft. The challenge has provided the team with the opportunity to improve design and manufacturing skills, while also gaining experience in real life engineering challenges. As a result, the team greatly increased their knowledge of aeronautical design and manufacturing. BYU-Idaho has developed a balsa/plywood carbon fiber reinforced fixed wing aircraft weighing approximately .7lbs, capable of carrying more than 4lbs.