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Many companies around the world have adopted the lean thinking as their strategy to operate, in a global market where changes happen all the time. One foundation for the success of lean manufacturing appliance is the continuous improvement approach which has been considered even on company statements, or it can be also considered as part of the genetic code of any enterprise. However, if in one side the continuous improvement thinking, set people mind to look for opportunities of improvement all the time, on other hand these improvements are incremental and they do not have significant impact on company performance on both short-term and medium-term and sometimes, the activities performed by the employees are not sustainable due to the lack of structure to manage and follow up these activities.

Although the Six Sigma [1] concept has become very popular in industrial sectors, very little is said about how to start a successful implementation in a Corporation, or when it should be initiated, and the most important, who should be addressed to lead this task. Its methodologies are widely observed by different sectors of the automotive market, typically focusing in projects with a potential financial impact, following the DMAIC sequence. More than just financial return, this sophisticated tool, has a direct impact on Quality in different levels for both non-productive process and manufacturing process, that eventually would also affect some organizational structures that ultimately can be understood as reengineering.

In recent years, the desire for improved vehicle performance, reliability and safety have increased the electrical content and its complexity in vehicles. Advanced automotive systems integrate sensors, controllers, actuators and communication networks. To maintain safety and reliability, a comprehensive system of diagnostics and physical and analytic redundancy are used. In some cases, diagnostic strategies based on analytical redundancy can provide detection, as well as fault-tolerance, and may provide benefits in cost, packaging, flexibility and reusability. This paper discusses a range of diagnostic methods and their applicability to advanced automotive systems such as X-by-Wire. It will also show the reduction to practice of an advanced analytical technique for an automotive application.

This paper is an extension to the work presented in part I [1]. The control objective is still the same - use a logic based control design technique to assign a wheel slip, λ, to each corner of a vehicle, to track overall desired vehicle dynamics. As in part I, a fuzzy logic based controller is the primary control, with additional logic to select the inside/outside classifiers for the wheels. In part I, only the reduction of yaw rate error, e, was considered. It was shown that, although the overall system had satisfactory performance, there was slight deteriorization in the tracking performance when trying to compensate through a significant vehicle sideslip angle, β. In this paper, additional logic is introduced into the control to limit the vehicle sideslip angle, β; thus, allowing for a more robust desired yaw rate, Ωd, tracking control performance. The emergency lane change maneuver is simulated to show the effectiveness of the redesigned control.

The lateral runout of disc brake corner components can lead to the generation of brake system pulsation. Emphasis on reducing component flatness and lateral runout tolerances are a typical response to address this phenomenon. This paper presents the results of an analytical study that examined the effect that the attachment of the wheel to the brake corner assembly could have on the lateral distortion of the rotor. An analysis procedure was developed to utilize the finite element method and simulate the mechanics of the assembly process. Calculated rotor distortions were compared to laboratory measurements. A statistical approach was utilized, in conjunction with the finite element method, to study a number of wheel and brake corner parameters and identify the characteristics of a robust design.

Continuous Improvement activities are often based on a list of top concerns, such as highest RPN (Risk Priority Number) on the PFMEA (Process Failure Modes and Effects Analysis), warranty items, or scrap rates. But a company is in business to make a profit for its stockholders. Therefore, money should be considered, rather than just technical engineering tools and RPNs. Current PFMEA methodology (See references 1 and 2) focuses on delivering quality parts to the customer. The financial impact of various potential process problems is not considered directly. A new and extended technique called FMERA (pronounced Fuh-MAIR-uh) can identify and prioritize the process part of potential problems that have the most financial impact on an operation. Alternatives can be evaluated to maximize the financial benefits. FMERA is a method for getting the voice of the stockholder into process decisions.

Seat belts are the primary occupant-protection devices for vehicle crashes. Field statistics show that proper usage of seat belts substantially contributes to decreases in the fatality rate and injury level. To collect first-hand information regarding seat belt comfort and usability, a questionnaire survey was conducted. The most significant problems were found as belt trapping in the door, awkward negotiating with clothes, belt twisting, belt locking up, and difficulty to locate the buckle. The survey results indicated that drivers who are over 40 years old have more complaints than younger drivers. When the driver's age increases to 55 and above, belt pulling force and inappropriate and loose fitting of the belt on the body become major issues. Female drivers have more complaints than male drivers. Short statured drivers need both hands to pull and guide the retracting of the belt.

In this study, US and UK accident data were analyzed to identify parameters that may influence rollover propensity to analyze driver injury rate. The US data was obtained from the weighted National Automotive Sampling System (NASS-CDS), calendar years 1992 to 1996. The UK pre-roll data was obtained from the national STATS 19 database for 1996, while the injury information was collected from the Co-operative Crash Injury Study (CCIS) database. In the US and UK databases, rollovers accounted for about 10% of all crashes with known crash directions. In the US and UK databases, most rollovers occurred when the vehicle was either going straight ahead or turning. The propensity for a rollover was more than 3 times higher when going around a bend than a non-rollover. In the UK, 74% of rollovers occurred on clear days with no high winds and 14% on rainy days with no high winds. In the US, 83% of rollovers took place in non-adverse weather conditions and 10% with rain.

In this study, U.S. accident data was analyzed to determine interior contacts and injuries for front-seated occupants in rollovers. The injury distribution for belted and unbelted, non-ejected drivers and right front passengers (RFP) was assessed for single-event accidents where the leading side of the vehicle rollover was either on the driver or passenger door. Drivers in a roll-left and RFP in roll-right rollovers were defined as near-side occupants, while drivers in roll-right and RFP in roll-left rollovers were defined as far-side occupants. Serious injuries (AIS 3+) were most common to the head and thorax for both the near and far-side occupants. However, serious spinal injuries were more frequent for the far-side occupants, where the source was most often coded as roof, windshield and interior.

Automotive occupant safety continues to evolve. At present this area has gathered a strong consumer interest which the vehicle manufacturers are tapping into with the introduction of many new safety technologies. Initially, individual passive devices and features such as seatbelts, knee- bolsters, structural crush zones, airbags etc., were developed for to help save lives and minimize injuries in accidents. Over the years, preventive measures such as improving visibility, headlights, windshield wipers, tire traction etc., were deployed to help reduce the probability of getting into an accident. With tremendous new research and improvements in electronics, we are at the stage of helping to actively avoid accidents in certain situations as well as providing increased protection to vehicle occupants and pedestrians.

In May 2000 the National Highway Traffic Safety Administration (NHTSA) issued the final rule for the Advanced Air Bag regulations effective MY 2004 for vehicles to be sold in the United States. These regulations are in response to the air bag-induced injuries seen in the field, especially to children and short women. Advanced air bags require a vehicle manufacturer to design air bags for a broad array of occupants: 12-month-old, 3-year-old and 6-year-old children, and 5th percentile adult females, as well as 50th percentile adult males with new and more stringent injury criteria. Requirements for minimizing air bag risks include automatically turning off the air bag in the presence of young children or deploying the air bag in a manner much less likely to cause serious or fatal injury to out-of-position occupants. Technologies that disable the air bag in the presence of young children or adults in out-of-position are termed as "suppression technologies.'

It is estimated that in the United States, nearly one quarter of all fatal automobile accidents involve a vehicle rollover. [1] In order to reduce fatalities and serious injuries, it is desirable to develop a sensing system that can detect an imminent rollover condition with sufficient time to activate occupant safety protection devices. The goals of a Rollover Sensing Module (RSM) are; 1 To accurately estimate vehicle roll and pitch angles 2 To reliably predict in a timely manner an imminent rollover 3 To eliminate false activation of safety devices 4 To function properly during airborne conditions 5 To be as autonomous as possible, not requiring information from other vehicle subsystems.

Electric power steering (EPS) is an advanced steering system that uses an electric motor to provide steering assist. Being a new technology it lacks the extensive operational history of conventional steering systems. Also conventional systems cannot be used to command an output independent of the driver input. In contrast EPS, by means of an electric motor, could be used to do so. As a result EPS systems may have additional failure modes, which need to be studied. In this paper we will consider the requirements for successful EPS operation. The steps required to develop diagnostics based on the requirements are also discussed. The results of this paper have been implemented in various EPS-based programs.

The industry strategy for automotive safety systems has been evolving over the last 20 years. Initially, individual passive devices and features such as seatbelts, airbags, knee bolsters, crush zones, etc. were developed for saving lives and minimizing injuries when an accident occurs. Later, preventive measures such as improving visibility, headlights, windshield wipers, tire traction, etc. were deployed to reduce the probability of getting into an accident. Now we are at the stage of actively avoiding accidents as well as providing maximum protection to the vehicle occupants and even pedestrians. Systems that are on the threshold of being deployed or under intense development include collision detection / warning / intervention systems, lane departure warning, drowsy driver detection, and advanced safety interiors.

Accurately predicting converter assembly deformation and mat pressure is essential in converter packaging design and manufacturing. In stuffing packaging, the annulus between the deformed shell and the catalyst is larger than that between the stuffing cone and the catalyst. As a result, the mat expands and undergoes unloading process. Tests show that the mat exhibits different loading and unloading characteristics. Using such a hysteresis mat pressure vs density curve in finite element analysis, the computed converter deformations closely agree with test data. Conversly, neglecting the mat hysteresis behavior may overestimate the deformation and pressure by a factor of three to four.

The purpose of this paper is to investigate occupant injuries which may be sustained during a single-event crash with known roll mechanism. The data was obtained from the weighted National Automotive Sampling System/ Crashworthiness Data System (NASS-CDS) for calendar years 1992 to 1996. The effect of number of rollover turns, roll direction, ejection and belt usage on driver injury responses was analyzed in single-event trip-overs. Trip-overs were chosen for the analysis because they account for over 50% of rollover crashes. The number of rollovers was divided in 3 categories: ¼ to ½ turn, ¾ to 1 turn and above 1 turn. Roll direction was either roll-left or a rollright along the longitudinal axis of the vehicle. Roll-left represents a roll with the driver side leading, while a roll right is with the right front passenger side leading. In the database used in this study, there were three times more belted drivers than unbelted.

It has been reported that lower extremity injuries represent a measurable portion of all moderate-to-severe automobile crash- related injuries. Thus, a simple tool to assist with the design of leg and foot injury countermeasures is desirable. The objective of this study is to develop a mathematical model which can predict load propagation and kinematics of the foot and leg in frontal automotive impacts. A multi-body model developed at the University of Virginia and validated for blunt impact to the whole foot has been used as basis for the current work. This model includes representations of the tibia, fibula, talus, hindfoot, midfoot and forefoot bones. Additionally, the model provides a means for tensioning the Achilles tendon. In the current study, the simulations conducted correspond to tests performed by the Transport Research Laboratory and the University of Nottingham on knee-amputated cadaver specimens.

Automotive wiring assembly design and manufacturing has evolved from a locally based business to a global business. It is common today to engineer the design of a wiring assembly in one region of the world, to manufacture it in a second region, and to assemble it into the vehicle in a third region. This creates a need for global collaboration, training and communications. Design for Manufacturability (DFM) is a tool that can aid in this, in developing common processes globally, and reducing the cost and design complexity of the product in the early design stages. To develop a global DFM process, an organization must develop and implement a strategy. This paper will review the approach that an automotive wiring assembly supplier adopted. It will enumerate the benefits of developing a global Design for Manufacturability process, selecting a champion, and using a twelve-step plan to integrate DFM into each region.

The SuperPlug™ door module is a new Delphi innovation. It is a one-piece composite structure, which integrates several door components into one assembly. This reduces the total part count, simplifies the vehicle level assembly process, and reduces labor cost (see the Appendix). The door slam durability test is an important factor in door module design. As more hardware is integrated into the SuperPlug, this subsystem performance in a door slam test becomes important. Therefore, the correct placement of components and the supporting structure is critical. Currently, the evaluation of door slam durability for the SuperPlug is a process of build then test. This is time consuming and costly due to a long testing lead-time and the expense of tooling a new mold. It was realized that a numerical process for assessing the effect of door slam would be required. This process would compute the dynamic response using finite element analysis (FEA).

This study compares the effect of US and European airbag deployments on injury outcomes for belted drivers in frontal crashes. Driver weight, height and seat track position was also examined in relation to those outcomes. This information may help to prioritize and guide the logic for “Smart” airbags. For the study, only airbag-equipped cars were considered. Two accident databases were used: 1) the weighted and unweighted National Accident Sampling System (NASS-CDS) from the US, calendar years 1995 to 1996, and 2) the unweighted Co-operative Crash Injury Study (CCIS) from the UK, calendar years 1992 to 1998. The parameters investigated were Injury Severity Score (ISS), Equivalent Test Speed (ETS), occupant weight, occupant height and seat location. For US drivers, the injury rate and occurrence were calculated using weighted data, while for UK drivers, the rate and occurrence were obtained using unweighted data.