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Video

Real-time Tire Imbalance Detection Using ABS Wheel Speed Sensors

2011-11-15
This presentation proposes an approach to use ABS wheel speed sensor signals together with other vehicle state information from a brake control module to detect an unbalanced tire or tires in real-time. The proposed approach consists of two-stage algorithms that mix a qualitative method using band-pass filtering with a quantitative parameter identification using conditional least squares. This two-stage approach can improve the robustness of tire imbalance or imbalances. The proposed approach is verified through vehicle testing and the test results show the effectiveness of the approach. Presenter Jianbo Lu, Ford Motor Co.
Video

Future Development of EcoBoost Technology

2012-05-10
Ford's EcoBoost GTDI engine technology (Gasoline Direct Injection, Turbo-charging and Downsizing) is being successfully implemented in the market place with the EcoBoost option accounting for significant volumes in vehicle lines as diverse as the F150 pickup truck, Edge CUV and the Lincoln MKS luxury sedan. A logical question would be what comes after GTDI? This presentation will review some of the technologies that will be required for further improvements in CO2, efficiency and performance building on the EcoBoost foundation as well as some of the challenges inherent in the new technologies and approaches. Presenter Eric W. Curtis, Ford Motor Co.
Technical Paper

Gear Whine Improvements for an Automatic Transmission through Design Retargeting and Manufacturing Variability Reduction

2001-04-30
2001-01-1505
Gear whine in 1st gear for an automatic transmission that has been in production for nearly thirty years was identified as an NVH issue. Due to advances in vehicle level refinement, and reduction of other masking noises, the automatic transmission gear whine became an issue with the customer. Since the transmission was already in production, the improvements had to be within the boundaries of manufacturing feasibility with existing equipment to avoid costly and time consuming investment in new machines. The approach used was one of identifying optimum values of existing gear parameters to provide a reduction in passenger compartment noise. The problem was in a light truck application. Objective noise measurements were recorded for 10 transmissions from more than 50 driven in vehicles. The transmissions were disassembled and the gears inspected.
Technical Paper

Robust Analysis of Vehicle Suspension System Uncertainty

2001-04-30
2001-01-1582
The paper presents the systematic approaches toward robust stability analysis of H2/H∞ controlled active suspension systems. The computational algorithms for the structured singular value μ are the main features of the work with an emphasis on quantifying the effects of uncertainty of the systems. The representation of vehicle parameter uncertainties is given in detail. The robustness test is subsequently done based on a quarter vehicle model. The results have showed that the H∞ controller is the best one on both robust stability and robust performance.
Technical Paper

Analysis of Instabilities and Power Flow in Brake Systems with Coupled Rotor Modes

2001-04-30
2001-01-1602
Recent investigations by others have indicated that the dynamic response of automotive brake rotors in the squeal frequency range involves the classic flexural modes as well as in-plane motion. While the latter set creates primarily in-plane displacements, there is coupling to transverse displacements that might produce vibrational instabilities. This question is investigated here by analyzing a modal model that includes two modes of the rotor and two modes of the pad and caliper assembly. Coupling between in-plane and transverse displacements is explicitly controlled. Results from this model indicate that the coupling does create vibrational instabilities. The instabilities, whose frequencies are in the squeal range, are characterized by power flow through the transverse motion of the rotor.
Technical Paper

Operational Spindle Load Estimation Methodology for Road NVH Applications

2001-04-30
2001-01-1606
A new experimental methodology has been developed to quantify spindle loads of a vehicle under actual operational conditions. The methodology applies an indirect six degree-of-freedom (6 DOF) frequency response function (FRF) measurement technique to obtain three translation/force and three rotation/moment FRFs of the suspension system of the vehicle. The Inverse Frequency Response Function (IFRF) method estimates the spindle loads under operational conditions. The feasibility and applicability of the developed methodology for vehicle road NVH applications was experimentally demonstrated. The results show that the methodology provides accurate spindle load estimation over a broad frequency range. This methodology can be used for benchmarking and target setting of spindle loads to achieve desired road NVH performance as well as for diagnosing root causes in problem solving applications.
Technical Paper

Steering Wheel Vibration Diagnosis

2001-04-30
2001-01-1607
The objective of this project was to develop a methodology for the diagnosis of vibrations of the vehicle's steering wheel. This paper will describe an attempt at developing a systematic approach for describing the vibrations felt, what the sources might be, and how various steering system parameters might affect the vibrations.
Technical Paper

Engine Excitation Decomposition Methods and V Engine Results

2001-04-30
2001-01-1595
Engine excitation forces have been studied in the past using one of two methods; a lumped sum or a totally distributed approach. The lumped sum approach gives the well-understood engine inherent unbalance and the totally distributed approach is used in engine CAE models to determine the overall engine response. The approach that will be described in this paper identifies an intermediate level of sophistication. The methodology implemented considers single cylinder forces on the engine block, piston side thrust and main bearing forces, and decomposes them into their order content. The forces are then phased and geometrically distributed appropriately for each cylinder and then each order is analyzed relative to know distributions that are NVH concerns, V-block breathing, block side wall breathing, and block lateral and vertical bending.
Technical Paper

Finite element simulation of drive shaft in truck/SUV frontal crash

2001-06-04
2001-06-0106
Drive shaft modelling effects frontal crash finite element simulation. A 35 mph rigid barrier impact of a body on frame SUV with an one piece drive shaft and a unibody SUV with a two piece drive shaft have been studied and simulated using finite element analyses. In the model, the drive shaft can take significant load in frontal impact crash. Assumptions regarding the drive shaft model can change the predicted engine motion in the simulation. This change influences the rocker @ B-pillar deceleration. Two modelling methods have been investigated in this study considering both joint mechanisms and material failure in dynamic impact. Model parameters for joint behavior and failure should be determined from vehicle design information and component testing. A body on frame SUV FEA model has been used to validate the drive shaft modeling technique by comparing the simulation results with crash test data.
Technical Paper

Fuel Economy Benefit of Cylinder Deactivation - Sensitivity to Vehicle Application and Operating Constraints

2001-09-24
2001-01-3591
A Variable Displacement Engine (VDE) improves fuel economy by deactivating half the cylinders at light load. The actual fuel economy benefit attained in the vehicle depends on how often cylinders can be deactivated, which is a function of test cycle, engine size, and vehicle weight. In practice, cylinder deactivation will also be constrained by NVH (noise, vibration, and harshness). This paper presents fuel economy projections for VDE in several different engine and vehicle applications. Sensitivity to NVH considerations is quantified by calculating fuel economy with and without cylinder deactivation in various operating modes: idle, low engine speed, 1st and 2nd gear, and warm-up after cold start. The effects of lug limits and calibration hysteresis are also presented.
Technical Paper

An Ultra-Light Thin Sliding Door Design - A Multi-Product Multi-Material Solution

2002-03-04
2002-01-0391
Sliding door designs are applied to rear side doors on vans and other large vehicles with a trend towards dual sliding doors with power operation. It is beneficial for the vehicle user to reduce the weight of and space occupied by these doors. Alcoa, in conjunction with Ford, has developed a multi-product, multi-material-based solution, which significantly reduces the cost of an aluminum sliding door and provides both consumer delight and stamping-assembly plant benefits. The design was successfully demonstrated through a concept readiness/technology demonstration program.
Technical Paper

Hybrid Powertrain with an Engine-Disconnecting Clutch

2002-03-04
2002-01-0930
Several types of hybrid-electric vehicles have been developed at Ford Research Laboratory. Among the parallel hybrid systems with a single electric motor, two types were studied. In the first type, the electric motor was attached directly to the crankshaft (mild hybrid) [1], to enable the engine start-stop and regeneration functions. In the second type (full hybrid) the electric motor was connected to the engine through the use of a clutch to allow electric launch of the vehicle and pure electric driving at low speeds. The full hybrid powertrain described in this paper uses a more powerful electric motor for enhanced regenerative braking and engine power assist. An engine-disconnecting clutch saves energy during both the electric propulsion and during vehicle braking. When the clutch is disengaged the engine is shut-off, which eliminates the energy otherwise spent on motoring the engine during electric propulsion.
Technical Paper

Understanding the Interaction Between Passive Four Wheel Drive and Stability Control Systems

2002-03-04
2002-01-1047
The purpose of this paper is to describe and define the interaction between a brake based stability control system and a passive coupler (viscous coupling unit) inside the transfer case of a Four-Wheel Drive (4WD) vehicle. This paper will focus on the driveline system and the impact that a stability control system can have on it. It will provide understanding of torque transfer on 4WD vehicles that are equipped with a brake based stability control system and use this knowledge to recommend ways to reduce the undesirable torque transfer interaction between the two systems. These recommendations can be readily applied to future 4WD/AWD vehicles to improve compatibility between the two systems.
Technical Paper

Development of an Improved Cosmetic Corrosion Test for Finished Aluminum Autobody Panels

2007-04-16
2007-01-0417
Since 2000, an Aluminum Cosmetic Corrosion task group within the SAE Automotive Corrosion and Protection (ACAP) Committee has existed. The task group has pursued the goal of establishing a standard test method for in-laboratory cosmetic corrosion evaluations of finished aluminum auto body panels. A cooperative program uniting OEM, supplier, and consultants has been created and has been supported in part by USAMP (AMD 309) and the U.S. Department of Energy. Prior to this committee's formation, numerous laboratory corrosion test environments have been used to evaluate the performance of painted aluminum closure panels. However, correlations between these laboratory test results and in-service performance have not been established. Thus, the primary objective of this task group's project was to identify an accelerated laboratory test method that correlates well with in-service performance.
Technical Paper

Simulation of Warm Forming Assisted Hemming to Study the Effect of Process Parameters on Product Quality

2007-04-16
2007-01-0420
Current trends in the auto industry requiring tighter dimensional specifications combined with the use of lightweight materials, such as aluminum, are a challenge for the traditional manufacturing processes. The hemming process, a sheet metal bending operation used in the manufacturing of car doors and hoods, poses problems meeting tighter dimensional tolerances. Hemming is the final operation that is used to fasten the outer panel with the inner panel by folding the outer panel over the inner panel. Roll in/out is one of the main quality concerns with hemming, and keeping it under tolerance is a high priority issue for the auto manufacturers. Current hemming process technology, given the mechanical properties of current materials, has reached its saturation limit to deliver consistent dimensional quality to satisfy customers and at the same time meet government standards.
Technical Paper

A Predictive Model for Feedgas Hydrocarbon Emissions: An Extension to Warm Engine Maps

2005-10-24
2005-01-3862
A feedgas hydrocarbon emissions model that extends the usefulness of fully-warmed steady-state engine maps to the cold transient regime was developed for use within a vehicle simulation program that focuses on the powertrain control system (Virtual Powertrain and Control System, VPACS). The formulation considers three main sources of hydrocarbon. The primary component originates from in-cylinder crevice effects which are correlated with engine coolant temperature. The second component includes the mass of fuel that enters the cylinder but remains unavailable for combustion (liquid phase) and subsequently vaporizes during the exhaust portion of the cycle. The third component includes any fuel that remains from a slow or incomplete burn as predicted by a crank angle resolved combustion model.
Technical Paper

Development of an Improved Cosmetic Corrosion Test for Finished Aluminum Autobody Panels

2005-04-11
2005-01-0542
A co-operative program initiated by the Automotive Aluminum Alliance and supported by USAMP continues to pursue the goal of establishing an in-laboratory cosmetic corrosion test for finished aluminum auto body panels that provides a good correlation with in-service performance. The program is organized as a task group within the SAE Automotive Corrosion and Protection (ACAP) Committee. Initially a large reservoir of test materials was established to provide a well-defined and consistent specimen supply for comparing test results. A series of laboratory procedures have been conducted on triplicate samples at separate labs in order to evaluate the reproducibility of the various lab tests. Exposures at OEM test tracks have also been conducted and results of the proving ground tests have been compared to the results in the laboratory tests. Outdoor tests and on-vehicle tests are also in progress. An optical imaging technique is being utilized for evaluation of the corrosion.
Technical Paper

Dynamic Modeling of Brake Friction Coefficients

2000-10-01
2000-01-2753
Friction behavior is one of the most critical factors in brake system design and performance. For up-front design and system modeling it is desirable to be able to describe a lining's frictional behavior as a function of the local conditions, such as contact pressure, temperature and sliding speed. Typically, frictional performance is assessed using brake dynamometer testing of full-scale hardware, and an average friction value is used during brake system development. This traditional approach yields an average brake friction coefficient that is hardware-dependent and fails to capture in-stop friction variation; it is also unavailable in advance of component testing, ruling out true up-front design and prediction. To address these shortcomings, a scaled inertial brake dynamometer was used to determine the frictional characteristics of candidate lining materials.
Technical Paper

A New FEA Method for the Evaluation of a Body Joint

2001-03-05
2001-01-0758
A finite element analysis method has been developed to assess the design of an automobile body joint. The concept of the coefficient of joint stiffness and the force distribution ratio are proposed accordingly. The coefficient of joint stiffness reveals whether a joint is stiff enough compared to its joining components. In addition, these parameters can be used to estimate the potential and the effectiveness for any further improvement of the joint design. The modeling and analysis of the proposed process are robust. The coefficient of joint stiffness could be further developed to serve as the joint design target.
Technical Paper

A Magnetorheological Door Check

2001-03-05
2001-01-0619
Several shortcomings of mechanical door checks are overcome using a magnetorheological damper. Because the damper is electrically actuated, it can check in any desired position. The logical decision to activate or release the door check can be made either by passive circuitry based on input signals from switches attached to door handles or under microprocessor control, in which case the decision can take into account a variety of unconventional input factors, including the magnitude of the force applied to the door, the rate of change of the applied force, and the angle of door opening. With the addition of an appropriate proximity sensor, the controllable damper can prevent the door from inadvertently hitting a nearby obstacle. Details of the damper mechanism are described, and several implemented control strategies, both passive and microprocessor based, are discussed.
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