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Turbulent jet ignition is a pre-chamber ignition enhancement method that produces a distributed ignition source through the use of a chemically active turbulent jet which can replace the spark plug in a conventional spark ignition engine. In this paper combustion visualization and characterization was performed for the combustion of a premixed propane/air mixture initiated by a pre-chamber turbulent jet ignition system with no auxiliary fuel injection, in a rapid compression machine. Three different single orifice nozzles with orifice diameters of 1.5 mm, 2 mm, and 3 mm were tested for the turbulent jet igniter pre-chamber over a range of air to fuel ratios. The performance of the turbulent jet ignition system based on nozzle orifice diameter was characterized by considering both the 0-10 % and the 10-90 % burn durations of the pressure rise due to combustion.

Piston temperature plays a major role in determining details of fuel spray vaporization, fuel film deposition and the resulting combustion in direct-injection engines. Due to different heat transfer properties that occur in optical and all-metal engines, it becomes an inevitable requirement to verify the piston temperatures in both engine configurations before carrying out optical engine studies. A novel Spot Infrared-based Temperature (SIR-T) technique was developed to measure the piston window temperature in an optical engine. Chromium spots of 200 nm thickness were vacuum-arc deposited at different locations on a sapphire window. An infrared (IR) camera was used to record the intensity of radiation emitted by the deposited spots. From a set of calibration experiments, a relation was established between the IR camera measurements of these spots and the surface temperature measured by a thermocouple.

Camless Variable Valve Actuation (VVA) technologies have been known for improving fuel economy, reducing emissions, and enhancing engine performance. VVA can be divided into electro-magnetic, electro-hydraulic, and electro-pneumatic actuation. A family of camless VVA designs (called LGD-VVA or Gongda-VVA) has been presented in an earlier SAE publication (SAE 2007-01-1295) that consists of a two-spring actuation, a bypass passage, and an electrohydraulic latch-release mechanism. The two-spring pendulum system is used to provide efficient conversion between the moving mass kinetic energy and the spring potential energy for reduced energy consumption and to be more robust to the operational temperature than the conventional electrohydraulic actuation; and the electrohydraulic mechanism is intended for latch-release function, energy compensation and seating velocity control.

Air-to-fuel (A/F) ratio is the mass ratio of the air-to-fuel mixture trapped inside a cylinder before combustion begins, and it affects engine emissions, fuel economy, and other performances. Using an A/F ratio and dual-fuel ratio control oriented engine model, a multi-input-multi-output (MIMO) sliding mode control scheme is used to simultaneously control the mass flow rate of both port fuel injection (PFI) and direct injection (DI) systems. The control target is to regulate the A/F ratio at a desired level (e.g., at stoichiometric) and fuel ratio (ratio of PFI fueling vs. total fueling) to any desired level between zero and one. A MIMO sliding mode controller was designed with guaranteed stability to drive the system A/F and fuel ratios to the desired target under various air flow disturbances.

Injury to the lower extremity during an automotive crash is a significant problem. While the introduction of safety features (i.e. seat belts, air bags) has significantly reduced fatalities, lower extremity injury now occurs more frequently, probably for a variety of reasons. Lower extremity trauma is currently based on a bone fracture criterion derived from human cadaver impact experiments. These impact experiments, conducted in the 1960's and 70's, typically used a rigid impact interface to deliver a blunt insult to the 90° flexed knee. The resulting criterion states that 10 kN is the maximum load allowed at the knee during an automotive crash when certifying new automobiles using anthropomorphic dummies. However, clinical studies suggest that subfracture loading can cause osteochondral microdamage which can progress to a chronic and debilitating joint disease.

Human intraspecific variation is a complex problem, but may be better understood by using computational models in tandem with knowledge about the genetic bases of phenotypic traits. These results can be used in a multitude of settings. To move closer to this goal, biologically-realistic mappings between genotype and phenotype are constructed using genetic algorithm and neural network-like models. These models allow for gene-gene and gene-environment interactions to be characterized in the resulting phenotype. Two types of model are introduced: a simple, two-layer model, and a more complex model. The final section will focus on trends of growth and development in relation to relationship to modeling anthropometric traits and other morphological phenomena.

Lower extremity (knee) injury prediction resulting from impact trauma is currently based on a bone fracture criterion derived from experiments on predominantly aged cadavers. Subsequent experimental and theoretical studies indicate that more aged, pathological specimens require higher, not lower, loads to initiate bone fracture. This suggests that a bone fracture criterion based solely on aged specimens may not be representative of the current driving population. In the current study, we sought to determine if cadaver age, physical size, sex, baseline joint pathology, or patellar geometry correlated with fracture load. An analysis was made of data from previous impact experiments conducted on fifteen isolated cadaver knees using a consistent impact protocol. The protocol consisted of sequentially increasing the impact energy with a rigid interface until gross fracture. Gross bone fractures occurred at loads of 6.9±2.0 kN (range 3.2 to 10.6 kN) using this protocol.

In developing a direct injection gasoline engine, the in-cylinder fuel air mixing is key to good performance and emissions. High speed visualization in an optically accessible single cylinder engine for direct injection gasoline engine applications is an effective tool to reveal the fuel spray pattern effect on mixture formation The fuel injectors in this study employ the unique multi-hole turbulence nozzles in a PFI-like (Port Fuel Injection) fuel system architecture specifically developed as a Low Pressure Direct Injection (LPDI) fuel injection system. In this study, three injector sprays with a narrow 40° spray angle, a 60°spray angle with 5°offset angle, and a wide 80° spray angle with 10° offset angle were evaluated. Image processing algorithms were developed to analyze the nature of in-cylinder fuel-air mixing and the extent of fuel spray impingement on the cylinder wall.

Injuries to the lower extremities are common during car accidents because the lower extremity is typically the first point of contact between the occupant and the car interior. While injuries to the knee, ankle and hip are usually not life threatening, they can represent a large societal burden through treatment costs, lost work days and a reduced quality of life. The aim of the current study was to specifically study injuries associated with the knee and to propose a methodology which could be used to prevent future knee injuries. To understand the scope of this problem, a study was designed to identify injury trends in car crashes for the years 1979-1995. The NASS (National Accident Sampling System) showed that 10% of all injuries were to the knee, second only to head and neck injuries. Most knee injuries resulted from knee-to-instrument panel contact. Subfracture injuries were most common (contusions, abrasions, lacerations) followed by gross fracture injuries.

Extensive crash sled testing and analysis has recently led to the development of a new HANS prototypes for use in FIA F1. The performance of HANS prototypes has been studied with various conditions of HANS design geometry and impact direction. The new HANS prototypes have been found to substantially reduce injurious motions and forces of the head and neck, and the new HANS is lighter, more compact, and performs better than the currently available HANS. Use of HANS by FIA F1 drivers has been initiated.

In an effort to create computer models to promote rapid, cost-effective prototyping while easing design changes, more information about how people interact with seats is needed. Predicting the occupant location, their geometry, and motion within a vehicle leads to a better determination of safety restraint location, controls reach, and visibility - factors that affect the overall operation of the vehicle. Based on the Michigan State University JOHN model, which provides a biomechanical simulation of the torso posture, experiments were conducted to examine the change of postures due to seat and interior package factors. The results can be incorporated into the posture prediction model of the RAMSIS program to give a more detailed prognosis of the spine curvature and refine the model-seat interactions. This paper will address findings of the experimental study with relation to model development.

In-cylinder visualization experiments were completed using an International VT275-based optical DI Diesel engine operating under high simulated exhaust gas recirculation combustion conditions. Experiments were run at four load conditions to examine variations in fuel spray, combustion, and soot production. Mass fraction burned analyses of pressure data were used to investigate the combustion processes of the various operating conditions. An infrared camera was used to visualize fuel spray events and exothermic combustion gases. A visible, high-speed camera was used to image natural luminosity produced by soot. The recorded images were post-processed to analyze the fuel spray, the projected exothermic areas produced by combustion, as well as soot production of different load conditions. Probability maps of combustion and fuel spray occurrence in the cylinder are presented for insight into the combustion processes of the different conditions.

A direct-injection and spark-ignition single-cylinder engine with optical access to the cylinder was used for the combustion visualization study. Gasoline and ethanol-gasoline blended fuels were used in this investigation. Experiments were conducted to investigate the effects of fuel injection pressure, injection timing and the number of injections on the in-cylinder combustion process. Two types of direct fuel injectors were used; (i) high-pressure production injector with fuel pressures of 5 and 10 MPa, and (ii) low-pressure production-intent injector with fuel pressure of 3 MPa. Experiments were performed at 1500 rpm engine speed with partial load. In-cylinder pressure signals were recorded for the combustion analyses and synchronized with the high-speed combustion imaging recording. Visualization results show that the flame growth is faster with the increment of fuel injection pressure.

A multicomponent droplet evaporation model which discretizes the one-dimensional mass and temperature profiles inside a droplet with a finite volume method has been developed and implemented into a large-eddy simulation (LES) model for spray simulations. The LES and multicomponent models were used along with the KH-RT secondary droplet breakup model to simulate realistic fuel sprays in a closed vessel. The effect of various spray and ambient gas parameters on the liquid penetration length of different single component and multicomponent fuels was investigated. The numerical results indicate that the spray penetration length decreases non-linearly with increasing gas temperature or pressure and is less sensitive to changes in ambient gas conditions at higher temperatures or pressures. The spray models and LES were found to predict the experimental results for n-hexadecane and two multicomponent surrogate diesel fuels reasonably well.

Since the 1960's, automotive seats have been designed and evaluated with tools and procedures described in the SAE Recommended Practice J826. The SAE J826 design template and testing manikin each have a torso with a flat lower back shape and with a single joint at the H-point. The JOHN models provide a more anatomically detailed representation of human shape and movement. The articulations of the JOHN torso (pelvic, lumbar, and thoracic) segments are coupled so that their relative positions are determined by a single parameter related to spinal curvature. This paper describes the development and use of the JOHN biomechanical models for seating design.

The human torso includes three major segments, the thoracic (rib cage) segment, lumbar segment, and pelvic segment to which the thighs are attached. The JOHN model was developed to represent the positions and movements of these torso segments along with the head, arms, and legs. Using the JOHN model, a new seat concept has been developed to support and move with the torso segments and thighs. This paper describes the background of the biomechanically articulated chair (BAC) and the development of BAC prototypes. These BAC prototypes have been designed to move with and support the thighs, pelvis, and rib cage through a wide variety of recline angles and spinal curvatures. These motions have been evaluated with computer modeling and with initial experience of human subjects. Results from computer modeling and human subjects show that the BAC will allow a broad range of torso postures.

Driver and passenger comfort, as related to automotive seats, is a growing issue in the automotive industry. As this trend continues, automotive seat designers and developers are generating a greater need for more anthropometrically accurate tools to aid them in their work. One tool being developed is the JOHN software program that utilizes three-dimensional solid objects to represent humans in seated postures. Contours have been developed to represent the outside skin surfaces of three different body types in a variety of postures in the sagittal plane. These body types include: the small female, the average male, and the large male.

To assist automotive seat development and evaluation, a technique for predicting the posture of seated occupants has been developed. The method involved modeling the torso geometry and articulation of a mid-size male, based on information presented in SAE paper number 930110 [1]. This mid-size male model, known as 2-D JOHN, was developed in a commercial kinetic modeling software and used in a comparative seat evaluation study between a current production automotive seat and a prototype articulating seat. The 2-D JOHN model was supported a greater range of postures, defined as Total Lumbar Curvature (TLC) and Torso Recline Angle (TRA), in the prototype seat than the automotive seat.

LiDAR sensors are common in automated driving due to their high accuracy. However, LiDAR processing algorithm development suffers from lack of diverse training data, partly due to sensors’ high cost and rapid development cycles. Public datasets (e.g. KITTI) offer poor coverage of edge cases, whereas these samples are essential for safer self-driving. We address the unmet need for abundant, high-quality LiDAR data with the development of a synthetic LiDAR point cloud generation tool and validate this tool’s performance using the KITTI-trained PIXOR object detection model. The tool uses a single camera raycasting process and filtering techniques to generate segmented and annotated class specific datasets.

This paper describes additional and more recent results from the DaimlerChrysler study of HANS that includes a sensitivity analysis of HANS performance to variations in crash dummy neck length and other impact test conditions. The objective of the tests was to determine the robustness of the HANS concept in a variety of conditions that might occur in actual use. The results show that the variations in test parameters do effect injury measures from the crash dummy, but HANS provides substantial reductions in injury potential in all cases compared to not using HANS. Also, no injuries were indicated with HANS.