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Certain problems associated with conventional vehicular speed sensing, such as wheel slip, wheel lock, and variable rolling radius, can be alleviated by employing microwave speed sensing. It is expected that true speed sensing will augment a number of automotive and other ground transportation applications. An experimental, two-horn, 55 GHz continuous wave radar speedometer designed to measure true ground speed in the presence of vehicular perturbations is described; the system has an ultimate design frequency of 60 GHz. An Impatt diode, solid-state transmitter was incorporated in this design because of its inherent advantages. The RF portion of the transmitter-receiver unit, including the dipole feed, is housed on a single microstrip circuit on an alumina substrate 1/2 X 1/4 in (12.7 X 6.35 mm). Vertically polarized beams incident at angles of 35 deg with respect to the horizontal system were chosen as a design compromise.

Researchers report an estimated 35.7 million of vehicles with touchscreens will be sold in 2019 worldwide [1]. As the use of touchscreens grows in the automotive industry, there is a need to study how driver’s arm and hand moves to access the touchscreen as well as how the driver utilizes the hardware around the touchscreen. In order to aid drivers while using the touchscreen and to minimize distractions, the drivers’ hand must be able to freely move to perform a task on the touchscreen without the trim interfering with the task. At the same time some trim may be used to support the hand and fingers while accessing the touchscreen particularly during tasks that take a longer period of time to complete. A study was performed to understand the effect of the size and the angle of a shelf placed under a touchscreen. Motion capture (Mocap) data of the hand of subjects performing two different tasks on the touchscreen was collected in the Human Occupant Package Simulator (HOPS).

Through the use of hybrid technology, Ford Motor Company continues to realize enhanced vehicle fuel economy while meeting customer performance and drivability targets. As is characteristic of all Ford Hybrid Electric Vehicles (HEVs), the basis for resolving these competing requirements resides with its Vehicle System Control (VSC) strategy. This strategy implements complex high-level executive controls to coordinate and optimize the desired operational state of the major HEV powertrain subsystems. To ensure that the VSC software meets its intended functionality, a software validation process developed at Research and Advanced Engineering has been integrated as part of the vehicle controls development process. In this paper, this VSC software validation process implemented for a next generation hybrid powertrain is presented. First, an overview of the hybrid powertrain application and the VSC software architecture is introduced.

The United States Department of Transportation (USDOT) and the Crash Avoidance Metrics Partnership-Vehicle Safety Communications 2 (CAMP-VSC2) Consortium (Ford, General Motors, Honda, Mercedes-Benz, and Toyota) initiated, in December 2006, a three-year collaborative effort in the area of wireless-based safety applications under the Vehicle Safety Communications-Applications (VSC-A) Project. The VSC-A Project developed and tested Vehicle-to-Vehicle (V2V) communications-based safety systems to determine if Dedicated Short Range Communications (DSRC) at 5.9 GHz, in combination with vehicle positioning, would improve upon autonomous vehicle-based safety systems and/or enable new communications-based safety applications.

This paper describes an indoor electromagnetic compatibility (EMC) testing facility designed for automotive testing over the 60 Hz to 18 GHz frequency range. The facility includes a large TEM cell, covering the 60 Hz to 20 MHz frequency range, and a state-of-the-art anechoic chamber, covering 20 MHz to 18 GHz. In addition to describing the test cells, this paper discusses testing methodology, automatic testing software and calibration. Data is presented depicting the electromagnetic field distribution in each test cell with and without the test vehicle in place. Data is also presented showing a typical field distribution near a high power shortwave transmitter site for correlation purposes.

A vehicle integrated sensing and analysis system has been designed, implemented, and demonstrated to nonintrusively monitor several biological signals of the driver. The biological driver signals measured by the system are the heart electrical signals or pseudo Lead-I electrocardiography (pLI-ECG), the galvanic skin response (GSR) or electrical conductance measured from the driver's fingers to palm, the palm skin temperature, the face skin temperature, and the respiration rate. The pLI-ECG and GSR measurements are made through direct contact of the driver hands with stainless steel electrodes integrated in the steering wheel rim. The temperature measurements are made with non-contacting infrared temperature sensors, also located on the steering wheel. The respiration rate was measured using a flexible thin film piezoelectric sensor affixed to the seatbelt.

Past studies have shown the applicability of advanced numerical methods for crashworthiness simulation. Lumped parameter (LP) modeling and finite element (FE) modeling have been demonstrated as two useful methodologies for achieving this endeavor. Experimental tests and analytical modeling using LP and FE techniques were performed on an experimental vehicle in order to evaluate the compatibility and interrelationship of the two numerical methods for crashworthiness simulation. The objective of the numerical analysis was to simulate the vehicle crashworthiness in a 0 degree, 48.6 KPH frontal impact. Additionally, a single commercial software, LS-DYNA3D, was used for both the LP and FE analysis.

Some of the best teaching methods are laboratory courses in which students experience application of the principles being presented. Preparing young engineering students for a career in the automotive industry challenges us to provide comparable opportunities to explore the dynamic performance of motor vehicles in a controlled environment. Today we are fortunate to have accurate and easy-to-use software programs making it practical for students to simulate the performance of motor vehicles on “virtual” proving grounds. At the University of Michigan the CarSim® vehicle dynamics simulation program has been introduced as such a tool to augment the learning experience. The software is used in the Automotive Engineering course to supplement homework exercises analyzing acceleration, braking, aerodynamics, and cornering performance. This paper provides an overview of the use of simulation in this setting.

Simulation of road loads in truck suspensions generally requires leaf-spring models. This paper presents a simple and accurate leaf-spring model that can be effectively used in analytical road load simulations using ADAMS software. The model topology is based on the familiar SAE “three-link” model. The model parameters are identified from static force-deflection test data. Alternatively, the parameters can be identified from a target design specification or from analytical “tests” on a detailed finite element model. The new leaf spring model has been validated for static and dynamic performance using laboratory test data.

The head, chest and femurs of three Hybrid II dummies were impacted with a ballistic pendulum at various angles to determine what differences in accelerometer and femur load cell output would result for a constant energy input. Also evaluated were suspicious tension loads in the femur load cell output when the legs were subjected to obvious off-center impacts during crash tests. It was found that the dummy legs can be subjected to very high torsion and bending loads which can have a significant effect on the femur load cell axial load outputs.

Due to the challenges in quantifying hand loads in manufacturing environments it is often assumed that the load is evenly distributed between the hands, even when handling parts with non-uniform mass distribution. This study estimated hand loads for six female subjects, when handling a custom part in 8 different configurations (2 weights, 4 CofM locations). The calculated hand loads varied from 20 to 50% of the weight being handled. The magnitude of asymmetrical hand loading depended on both the part orientation and the location of the CoM. Based on this study the knowledge of part weight, CofM location and hand positioning will allow the users of digital human models to perform more realistic and reliable task analysis assessments as the force distributions will be more representative of the actual loading rather than simply assuming the load is evenly distributed between the hands.

Variations in human skull thickness affecting human head dynamic impact responses were studied by finite element modeling techniques, experimental measurements, and histology examinations. The aims of the study were to better understand the influences of skull thickness variations on human head dynamic impact responses and the injury mechanisms of human head during direct impact. The thicknesses of the frontal bone of seven human cadaver skulls were measured using ultrasonic technology. These measurements were compared with previous experimental data. Histology of the skull was recorded and examined. The measured data were analyzed and then served as a reference to vary the skull thickness of a previously published three-dimensional finite element human head model to create four models with different skull thickness. The skull thicknesses modeled are 4.6 mm, 5.98 mm, 7.68 mm, and 9.61 mm.

The dilemma of using a shoulder belt force limiter with a 3-point belt system is selecting a limit load that will balance the reduced risk of significant thoracic injury due to the shoulder belt loading of the chest against the increased risk of significant head injury due to the greater upper torso motion allowed by the shoulder belt load limiter. However, with the use of air bags, this dilemma is more manageable since it only occurs for non-deploy accidents where the risk of significant head injury is low even for the unbelted occupant. A study was done using a validated occupant dynamics model of the Hybrid III dummy to investigate the effects that a prescribed set of shoulder belt force limits had on head and thoracic responses for 48 and 56 km/h barrier simulations with driver air bag deployment and for threshold crash severity simulations with no air bag deployment.

In modern automobiles, many new complex features are enabled by software and sensors. When combined with the variability of real-world environments and scenarios, validation of this ever-increasing amount of software becomes complex, costly, and takes a lot of time. This challenges automakers ability to quickly and reliably develop and deploy new features and experiences that their customers want in the marketplace. While traditional validation methods and modern virtual validation environments can cover most new feature testing, it is challenging to cover certain real-world scenarios. These scenarios include variation in weather conditions, roadway environments, driver usage, and complex vehicle interactions. The current approach to covering these scenarios often relies on data collected from long vehicle test trips that try to capture as many of these unique situations as possible. These test trips contribute significantly to the validation cost and time of new features.

Little has been reported in the literature on the compressive properties of muscle. These data are needed for the development of finite element models that address impact of the muscles, especially in the study of pedestrian impact. Tests were conducted to characterize the compressive response of muscle. Volunteers, cadaveric specimens and a Hybrid III dummy were impacted in the posterior and lateral aspect of the lower leg using a free flying pendulum. Volunteer muscles were tested while tensed and relaxed. The effects of muscle tension were found to influence results, especially in posterior leg impacts. Cadaveric response was found to be similar to that of the relaxed volunteer. The resulting data can be used to identify a material law using an inverse method.

Flanging is a secondary operation in sheet metal forming processes. Traditionally, the design of flange shape and trim line is based on an engineer's experience. It takes several iterations to achieve the desired flange geometry because of potential splits. In this paper, an efficient CAE-based tool is developed to quickly predict the formability of a given flange design and enable the optimization of trim lines. A numerical algorithm is formulated in this CAE tool to convert the 3D flanging process into an equivalent in-plane deformation problem. The developed CAE tool is also integrated with the optimization software LS-OPT for trim line design.

This paper describes some methods for greatly reducing or possibly eliminating subjective tuning of suspension parts for ride and handling. Laptop computers can now be used in the vehicle to guide the tuning process. The same tools can be used to select solutions that reduce sensitivity to production and environmental variations. OBJECTIVE Reduce or eliminate time required for tuning of suspension parts for ride characteristics. Improve the robustness of ride performance relative to variations in ambient temperature and production tolerances. PROBLEM REQUIRING SOLUTION AND METHOD OF APPROACH Traditional development programs for new vehicles include time-consuming subjective ride evaluations. One example is shock absorber tuning. Even if sophisticated models define force-velocity curves, numerous hardware iterations are needed to find valvings that will reproduce the curves. Many evaluation rides are needed to modify the valvings to meet performance targets.

This paper introduces several requirements that have been created based on lessons learned at Ford Motor Company. This is not a collection of requirements already addressed by MISRA. These are requirements which address repeated or costly problems that have been observed at Ford Motor Company in their Electronic Body Modules. Real world examples of why they were needed will be highlighted as well as the principles used to create them and confirm compliance. Electronic Body Modules at Ford Motor Company usually control Interior Lighting, Exterior Lighting, Chime, Wipers, Power Mirrors, Power Seats and other features related to passenger comfort. These modules typically use less than 32 K of ROM and are written in C. While some modules are connected to a vehicle network, others are stand-alone.

SmartDeviceLink (SDL) is open-source software that connects the vehicle’s infotainment system to mobile applications. SDL includes an open-source software development kit (SDK) that enables a smart-device to connect to the vehicle’s human-machine interface (HMI), read vehicle data, and control vehicle sub-systems such as the audio and climate systems. It is extensible, so other convenience subsystems or brought-in aftermarket modules can be added. Consequently, it provides a platform for cyber-physical systems that can integrate wearables, consumer sensors and cloud data into an intelligent vehicle control system. As an Open Innovation Platform, new features can be rapidly developed and deployed to the market, bypassing the longer vehicle development cycles. This facilitates a channel for rapid prototyping and innovation that is not constrained by the traditional process of automotive parts development, but is rather on the timeline of software development.

This paper summarizes the rationale used to specify the geometric, inertial and impact response requirements for a small adult female dummy and a large adult male dummy with impact biofidelity and measurement capacity comparable to the Hybrid III dummy, the most advanced midsize adult male dummy. Body segment lengths and weights for these two dummies were based on the latest anthropometry studies for the extremes of the U.S.A. adult population. Other characteristic body segment dimensions were calculated from geometric and mass scaling relationships that assured that each body segment had the same mass density as the corresponding body segment of the Hybrid III dummy. The biomechanical impact response requirements for the head, neck, chest and knee of the Hybrid III dummy were scaled to give corresponding biomechanical impact response requirements for each dummy.