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As engines are equipped with an increased number of control actuators to meet fuel economy targets, they become more difficult to control and calibrate. The additional complexity created by a larger number of control actuators motivates the use of physics-based control strategies to reduce calibration time and complexity. Combustion phasing, as one of the most important engine combustion metrics, has a significant influence on engine efficiency, emissions, vibration and durability. To realize physics-based engine combustion phasing control, an accurate prediction model is required. This research introduces physics-based control-oriented laminar flame speed and turbulence intensity models that can be used in a quasi-dimensional turbulent entrainment combustion model. The influence of laminar flame speed and turbulence intensity on predicted mass fraction burned (MFB) profile during combustion is analyzed.

Exhaust gas turbo-charging helps exploit the improved fuel efficiency of downsized engines by increasing the possible power density from these engines. However, turbo-charged engines exhibit poor transient performance, especially when accelerating from low speeds. In addition, during low-load operating regimes, when the exhaust gas is diverted past the turbine with a waste-gate or pushed through restricted vanes in a variable geometry turbine, there are lost opportunities for recovering energy from the enthalpy of the exhaust gas. Similar limitations can also be identified with mechanical supercharging systems. This paper proposes an electrical supercharging and turbo-generation system that overcomes some of these limitations. The system decouples the activation of the air compression and exhaust-energy recovery functions using a dedicated electrical energy storage buffer. Its main attributes fast speed of response to load changes and flexibility of control.

Recent research at Clemson University has focused on the development of an advanced non-pneumatic, non-elastomeric lunar wheel for NASA with superior traction. This paper reports on several concepts for tread materials and geometries that have been explored for tire-on-sand use. Specifically, fourteen concepts, involving the use of metal meshes, textile carpet materials, soft grousers, foams, and screens, were physically tested in an on-vehicle environment. Prototypes for each concept and formal test procedures to quantify traction were developed. This paper presents the results of the tests for several different concepts and the comparison between the concepts that were developed. Students developed their own testing environment through which these test procedures are implemented, an inclined hill 45 ft. in length and 8 ft. wide will approximately 6 inches deep filled with sand.

The number of control actuators available on spark-ignition engines is rapidly increasing to meet demand for improved fuel economy and reduced exhaust emissions. The added complexity greatly complicates control strategy development because there can be a wide range of potential actuator settings at each engine operating condition, and map-based actuator calibration becomes challenging as the number of control degrees of freedom expand significantly. Many engine actuators, such as variable valve actuation and flow control valves, directly influence in-cylinder combustion through changes in gas exchange, mixture preparation, and charge motion. The addition of these types of actuators makes it difficult to predict the influences of individual actuator positioning on in-cylinder combustion without substantial experimental complexity.

Motor vehicle crashes involving novice drivers are significantly higher than matured driver incidents as reported by the National Highway Traffic Safety Administration Fatality Analysis Reporting System (NHTSA-FARS). Researchers around the world and the United States are focused on how to decrease crashes for this driver demographic. Novice drivers usually complete driver education classes as a pre-requisite for full licensure to improve overall knowledge and safety. However, compiled statistics still indicate a need for more in-depth training after full licensure. An opportunity exists to supplement in-vehicle driving with focused learning modules using automotive simulators. In this paper, a training program for “Following Etiquette” and “Situational Awareness” was developed to introduce these key driving techniques and to complete a feasibility study using a driving simulator as the training tool.

In developing a nonlinear steering system model for vehicle simulation, it was determined that proper inclusion of system friction is necessary to correctly predict steering wheel torque response in on-center driving using simulation models. A method to characterize the inherent friction behavior for a given steering gear has been developed and performed on two types of power steering gears: a recirculating ball gear and a rack-and-pinion gear. During this research it was discovered that levels of static and dynamic friction can differ widely for these two types. Therefore this characterization procedure provides a method to ascertain both static and dynamic friction levels. The results from these tests show that friction levels can depend on steering gear input shaft position, steering gear input angular velocity and steering gear loading conditions.

The newly initiated Clemson Motorsports Engineering Program, housed in the Department of Mechanical Engineering, provides unique educational opportunities to our students combining classroom engineering education, research, and race team experience. Additionally, the research and service projects conducted provide valuable information to race teams and companies in the automotive industry as well as involving students in both applied technology development and fundamental engineering activities. This paper describes the current activities and structure of the program together with our view for future development.

According to the National Highway Traffic Safety Administration (NHTSA), motor collisions account for nearly 2.4 million injuries and 37 thousand fatalities each year in the United States. A great deal of research has been done in the area of vehicular safety, but very little has been completed to ensure licensed drivers are properly trained. Given the inherent risks in driving itself, the test for licensure should be uniform and consistent. To address this issue, an inexpensive, portable data acquisition and analysis system has been developed for the evaluation of driver performance. A study was performed to evaluate the system, and each participant was given a normalized driver rating. The average driver rating was μ=55.6, with a standard deviation of σ=12.3. All but 3 drivers fell into the so-called “Target Zone”, defined by a Driver Rating of μ± 1σ.

Driver modeling is essential to both vehicle design and control unit development. It can improve the understanding of human driving behavior and decrease the cost and risk of vehicle system verification and validation. In this paper, three driver models were implemented to simulate the behavior of drivers subject to a run-off-road recovery event. Target path planning, pursuit behavior, compensate behavior, physical limitations, and neuromuscular modeling were taken into consideration in the feedforward/feedback driver model. A transfer function driver model and a cost function based driver model from a popular vehicle simulation software were also simulated and a comparison of these three models was made. The feedforward/feedback driver model exhibited the best balance of performance with smallest overshoot (0.226m), medium settling time (1.20s) and recovery time (4.30s).

Driving skills and driving experience develop differently between a civilian and a military service member. Since 2000, the Department of Defense reports that two-thirds of non-related to war fatalities among active duty service members were due to transportation-related incidents. In addition, vehicle crashes are the leading non-related to war cause of both fatalities and serious injuries among active duty Marines. A pilot safe driving program for Marines was jointly developed by the Richard Petty Driving Experience and Clemson University Automotive Safety Research Institute. The pilot program includes four modules based on leading causes of vehicle crashes, and uses classroom and behind the wheel components to improve and reinforce safe driving skills and knowledge. The assessment results of this pilot program conducted with 192 Marines in September 2011 at Camp LeJeune, NC are presented and discussed.

The automotive sector has taken a keen interest in lightweighting as new required performance standards for fuel economy come into place. This strategy includes parts consolidation, design optimization, and material substitution, with sustainable polymers playing a major role in reducing a vehicle’s weight. Sustainable polymers are largely biodegradable, biocompatible, and sourced from renewable plant and agricultural stocks. A facile way to enhance their properties, so they can indeed replace the ones made from fossil fuels, is by reinforcing them with fibers to make composites. Natural fibers are gaining more acceptance in the industry due to their renewable nature, low cost, low density, low energy consumption, high specific strength and stiffness, CO2 sequestration potential, biodegradability, and less wear imposed on machinery. Biocomposites then become a very feasible way to help address the fuel consumption challenge ahead of us.

This set consists of three books, Design of Automotive Composites, CAE Design and Failure Analysis of Automotive Composites, and Biocomposites in Automotive Applications all developed by Dr. Charles Lu and Dr. Srikanth Pilla. Design of Automotive Composites reports successful designs of automotive composites occurred recently in this arena, CAE Design and Failure Analysis of Automotive Composites focuses on the latest use of CAE (Computer-Aided Engineering) methods in design and failure analysis of composite materials and structures, and Biocomposites in Automotive Applications, focuses on processing and characterization of biocomposites, their application in the automotive industry and new perspectives on automotive sustainability. Together, they are a focused collection providing the reader with must-read technical papers, hand-picked by the editors, supporting the growing importance of the use of composites in the ground vehicle industry. Dr. Charles Lu is H.E.