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Driver’s Response Prediction Using Naturalistic Data Set

SAE International Journal of Advances and Current Practices in Mobility

SEA, Ltd.-Gary Heydinger
Ohio State University-Venkata Raghava Ravi Lanka, Dennis Guenther
  • Journal Article
  • 2019-01-0128
Published 2019-04-02 by SAE International in United States
Evaluating the safety of Autonomous Vehicles (AV) is a challenging problem, especially in traffic conditions involving dynamic interactions. A thorough evaluation of the vehicle’s decisions at all possible critical scenarios is necessary for estimating and validating its safety. However, predicting the response of the vehicle to dynamic traffic conditions can be the first step in the complex problem of understanding vehicle’s behavior. This predicted response of the vehicle can be used in validating vehicle’s safety.In this paper, models based on Machine Learning were explored for predicting and classifying driver’s response. The Naturalistic Driving Study dataset (NDS), which is part of the Strategic Highway Research Program-2 (SHRP2) was used for training and validating these Machine Learning models. Various popular Machine Learning Algorithms were used for classifying and predicting driver’s response, such as Extremely Randomized Trees and Gaussian Mixture Model based Hidden Markov Model, which are widely used in multiple domains.For classifying driver’s response, longitudinal acceleration vs lateral acceleration plot (Ax-Ay plot) was divided into nine different classes and selected Machine Learning models were trained for predicting…
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Motorcycle Lean Angle Variation around a Constant Radius Curve at Differing Speeds and Travel Paths with an Evaluation of Data Measurement Systems

SEA, Ltd.-Ronny Wahba, Thomas Timbario, Jonathan Nelson, Fawzi Bayan, Dalton Jordan, Jonathan Swanson, Ashley Dunn
Published 2019-04-02 by SAE International in United States
Recent studies evaluating motorcycle lean angle have compared theoretical lean angle equations with real-world-tested motorcycle lean angles. These studies have considered several factors affecting lean angle, including the simplified assumptions made when calculating theoretical lean angles, the speed of the motorcycle around a curve, and the geometry of the roadway/curve. This study further evaluates motorcycle lean angle as a function of speed, but primarily focuses on the effects of different travel paths selected by the rider around the same constant radius curve. The testing incorporates nine passes around the same curve traveling three different paths at three different speeds. The real-world-tested lean angles were compared to the predicted calculated lean angles for each tested travel path and speed. The theoretical lean angles were calculated using the graphically reconstructed radius of curvature generated through three-dimensional (3D) laser scans of the roadway and aerial video footage and orthomosaic imagery. The orthomosaic imagery was collected via small Unmanned Aerial Vehicle (sUAV) (commonly referred to as a drone). The analyzed curve is a sweeping constant radius left-hand curve with…
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Motorcycle Accelerations while Successfully Traversing Roadway Irregularities and Traffic Calming Devices (Speed Bumps) at Small Lean Angles

SEA, Ltd.-Ronny Wahba, Jonathan Nelson, Thomas Timbario, Dalton Jordan, Fawzi Bayan, Edward Adams III, Ashley Dunn
Published 2019-04-02 by SAE International in United States
There have been limited empirical studies regarding the dynamics of a motorcycle and rider as a motorcycle traverses a roadway irregularity such as a pothole or depression, or a traffic calming device (TCD) such as a speed bump. This study seeks to establish qualitative analysis of the success of motorcycles traversing various roadway irregularities/TCDs as well as quantitatively analyzing accelerations to the motorcycle at varying speeds and lean angles. Further analysis is conducted comparing the accelerations experienced in scenarios where the suspension of the motorcycle experiences extension followed by compression, as is the case when encountering a pothole or depression, as well as scenarios where the suspension of the motorcycle experiences compression followed by extension, as is the case when encountering a TCD. Largely, the study is to establish minimum values for both speeds and lean angles in which traversing roadway irregularities\TCDs of a given geometry causes little to no dynamic instability to the motorcycle and little to no discomfort to the rider. The roadway irregularities/TCDs are traversed perpendicularly and at varying lean angles. Roadway…
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The Effect of Application Air Pressure on Brake Stroke Measurements from 70 to 125 psi

SEA, Ltd.-Ashley L. Dunn, Brian Boggess, Nicholas Eiselstein, Michael Dorohoff, Harold Ralston
Published 2015-09-29 by SAE International in United States
Brake chamber construction allows for a finite stroke for pushrods during brake application. As such, the Federal Motor Carrier Safety Regulations (FMCSRs) mandate maximum allowable strokes for the various chamber types and sizing. Brake strokes are often measured during compliance inspections and post-accident investigations in order to assess vehicle braking performance and/or capability. A number of studies have been performed, and their results published, regarding the effect of brake stroke and function on braking force and heavy truck stopping performance [1] through [4]. All of the studies have relied on a brake supply pressure of 100 pounds per square inch (psi). When brake strokes are measured in the field, following the Commercial Vehicle Safety Alliance (CVSA) procedure, the application pressure is prescribed to be maintained between 90 and 100 psi. However, circumstances that are difficult for investigators to control in the field often result in brake stroke measurements being taken with the application pressure outside of the CVSA-prescribed range. Although opinions have been offered regarding suitable correction factors, the authors could not locate any published…
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Tractor-Semitrailer Stability Following a Steer Axle Tire Blowout at Speed and Comparison to Computer Simulation Models

SEA, Ltd.-Anthony Cornetto, Fawzi Bayan, Ashley Dunn, Charles Tanner, Ronny Wahba, Jeffrey Suway, Gary J. Heydinger
Ohio State Univ.-Krishnan Chakravarthy, Dennis A. Guenther
Published 2013-04-08 by SAE International in United States
This paper documents the vehicle response of a tractor-semitrailer following a sudden air loss (Blowout) in a steer axle tire while traveling at highway speeds. The study seeks to compare full-scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models. Full-scale testing of a tractor-semitrailer experiencing a sudden failure of a steer axle tire was conducted. Vehicle handling parameters were recorded by on-board computers leading up to and immediately following the sudden air loss. Inertial parameters (roll, yaw, pitch, and accelerations) were measured and recorded for the tractor and semitrailer, along with lateral and longitudinal speeds. Steering wheel angle was also recorded. These data are presented and also compared to the results of computer simulation models. The first simulation model, SImulation MOdel Non-linear (SIMON), is a vehicle dynamic simulation model within the Human Vehicle Environment (HVE) software environment. This program includes a vehicle dynamic model capable of simulating vehicle motion in 3-dimensional environments and includes Brake Designer, ABS Simulation, and Tire Blowout models. The second model, TruckSim, is a vehicle…
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Modeling of a 6×4 Tractor and Trailers for Use in Real Time Hardware in the Loop Simulation for ESC Testing

SEA, Ltd.-Gary J. Heydinger
National Hwy Traffic Safety Admin.-W. Riley Garrott
Published 2013-04-08 by SAE International in United States
According to NHTSA's 2011 Traffic Safety Facts [1], passenger vehicle occupant fatalities continued the strong decline that has been occurring recently. In 2011, there were 21,253 passenger vehicles fatalities compared to 22,273 in 2010, and that was a 4.6% decrease. However; large-truck occupant fatalities increased from 530 in 2010 to 635 in 2011, which is a 20% increase. This was a second consecutive year in which large truck fatalities have increased (9% increase from 2009 to 2010). There was also a 15% increase in large truck occupant injuries from 2010. Moreover, the fatal crashes involving large trucks increased by 1.9%, in contrast to other-vehicle-occupant fatalities that declined by 3.6% from 2010.The 2010 accident statistics NHTSA's report reveals that large trucks have a fatal accident involvement rate of 1.22 vehicles per 100 million vehicle miles traveled compared to 1.53 for light trucks and 1.18 for passenger cars. This translates to a fatal accident involvement rate of 32.35 vehicles per 100,000 registered large trucks compared to 17.02 for light trucks and 13.09 for passenger cars. These statistics…
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Brake Characteristics for a Bobtail Vehicle

Yuri Prokrym, Andrew Price
SEA, Ltd.-Fawzi P. Bayan, Anthony Cornetto, Ashley Dunn, Ronny Wahba, Jeffrey Suway
Published 2013-04-08 by SAE International in United States
Bobtail testing data published in the literature are limited and the difference in deceleration of a bobtail configuration compared to a tractor-trailer has not been fully evaluated in the past. The authors seek to increment and update previous research on the topic.This paper presents detailed braking characteristic information obtained from full scale instrumented testing of a bobtail vehicle at various speeds. Brake timing is analyzed for the tested condition to determine the overall braking characteristics. The findings of this study are compared to 1) other testing performed with the same tractor configured with a trailer at different loading conditions and 2) to results published in literature for both bobtail vehicles and other loading conditions for both 6×4 and 4×2 tractor axle configurations.The brake timing data were collected during several days of full scale instrumented testing of a tractor and semitrailer performed at the Transportation Research Center in East Liberty, Ohio. Instrumented braking tests were performed at two speeds of 13.4 m/s (30 mph) and 27 m/s (60 mph) for the three configurations discussed in this…
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Stiffness Coefficients of Heavy Commercial Vehicles

SEA, Ltd.-Fawzi P. Bayan, Jeffrey Suway, Anthony Cornetto, Alfred Cipriani, Ronny Wahba
University of Maryland-Nicolas Poirette
Published 2013-04-08 by SAE International in United States
Accident reconstruction specialists have long relied on post-crash deformation and energy equivalence calculations to determine impact severity and the experienced change in velocity during the impact event. In order to utilize post-crash deformation, information must be known about the vehicle's structure and its ability to absorb crash energy. The Federal Motor Vehicle Safety Standards (FMVSS), the New Car Assessment Program (NCAP), and the Insurance Institute of Highway Safety (IIHS), have created databases with crash testing data for a wide range of vehicles. These crash tests allow reconstruction specialists to determine a specific vehicle's ability to absorb energy as well as to generalize the energy absorption characteristics across vehicle classes. These methods are very well publicized.Crash tests of commercial vehicles, however, are less common; and as a result, current literature has more limited information on the energy absorption characteristics of heavy vehicles such as traditional heavy trucks, motor coaches, buses or cab-over trucks.This paper attempts to quantify energy absorption characteristics for the aforementioned vehicle types based on publicly available frontal-impact crash tests reports and videos of…
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Validation of Real Time Hardware in the Loop Simulation for ESC Testing with a 6×4 Tractor and Trailer Models

SAE International Journal of Commercial Vehicles

SEA, Ltd.-Gary J. Heydinger
National Hwy Traffic Safety Admin.-Frank Barickman
  • Journal Article
  • 2013-01-0692
Published 2013-04-08 by SAE International in United States
The tractor trailer models discussed in this paper were for a real-time hardware-in-the-loop (HIL) simulation to test heavy truck electronic stability control (ESC) systems [1]. The accuracy of the simulation results relies on the fidelity and accuracy of the vehicle parameters used. However in this case where hardware components are part of the simulation, their accuracy also affects the proper working of the simulation and ESC unit. Hence both the software and hardware components have to be validated.The validation process discussed in this paper is divided into two sections. The first section deals with the validation of the TruckSim vehicle model, where experimental data is compared with simulation results from TruckSim. Once the vehicle models are validated, they are incorporated in the HIL simulation and the second section discusses the validation of the whole HIL system with ESC.It is shown that the HIL simulation is able to predict the vehicle responses with a high degree of correlation even for limit dynamic maneuvers. This gives us confidence that the HIL simulations can be used to perform…
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The Design of a Suspension Parameter Identification Device and Evaluation Rig (SPIDER) for Military Vehicles

SAE International Journal of Commercial Vehicles

SEA, Ltd.-Dale Andreatta, Gary J. Heydinger, Anmol Sidhu, Ronald Bixel
The Ohio State University-Timothy Wagner, Dennis A. Guenther
  • Journal Article
  • 2013-01-0696
Published 2013-04-08 by SAE International in United States
This paper describes the mechanical design of a Suspension Parameter Identification Device and Evaluation Rig (SPIDER) for wheeled military vehicles. This is a facility used to measure quasi-static suspension and steering system properties as well as tire vertical static stiffness. The machine operates by holding the vehicle body nominally fixed while hydraulic cylinders move an “axle frame” in bounce or roll under each axle being tested. The axle frame holds wheel pads (representing the ground plane) for each wheel. Specific design considerations are presented on the wheel pads and the measurement system used to measure wheel center motion. The constraints on the axle frames are in the form of a simple mechanism that allows roll and bounce motion while constraining all other motions. An overview of the design is presented along with typical results.
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