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Technical Paper

A Unified, Scalable and Replicable Approach to Development, Implementation and HIL Evaluation of Autonomous Shuttles for Use in a Smart City

As the technology in autonomous vehicle and smart city infrastructure is developing fast, the idea of smart city and automated driving has become a present and near future reality. Both Highway Chauffeur and low speed shuttle applications are tested recently in different research to test the feasibility of autonomous vehicles and automated driving. Based on examples available in the literature and the past experience of the authors, this paper proposes the use of a unified computing, sensing, communication and actuation architecture for connected and automated driving. It is postulated that this unified architecture will also lead to a scalable and replicable approach. Two vehicles representing a passenger car and a small electric shuttle for smart mobility in a smart city are chosen as the two examples for demonstrating scalability and replicability.
Technical Paper

Adaptation of TruckSim Models to Simulate Experimental Heavy Truck Hard Braking Test Data Under Various Levels of Brake Disablement

This research focuses on the development and performance of analytical models to simulate a tractor-semitrailer in straight-ahead braking. The simulations were modified and tuned to simulate full-treadle braking with all brakes functioning correctly, as well as the behavior of the tractor-semitrailer rig under full braking with selected brakes disabled. The models were constructed in TruckSim and based on a tractor-semitrailer used in dry braking performance testing. The full-scale vehicle braking research was designed to define limits for engineering estimates on stopping distance when Class 8 air-braked vehicles experience partial degradation of the foundation brake system. In the full scale testing, stops were conducted from 30 mph and 60 mph, with the combination loaded to 80,000 lbs (gross combined weight or GCW), half payload, and with the tractor-semitrailer unladen (lightly loaded vehicle weight, or LLVW).
Technical Paper

Application of Adversarial Networks for 3D Structural Topology Optimization

Topology optimization is a branch of structural optimization which solves an optimal material distribution problem. The resulting structural topology, for a given set of boundary conditions and constraints, has an optimal performance (e.g. minimum compliance). Conventional 3D topology optimization algorithms achieve quality optimized results; however, it is an extremely computationally intensive task which is, in general, impractical and computationally unachievable for real-world structural optimal design processes. Therefore, the current development of rapid topology optimization technology is experiencing a major drawback. To address the issues, a new approach is presented to utilize the powerful abilities of large deep learning models to replicate this design process for 3D structures. Adversarial models, primarily Wasserstein Generative Adversarial Networks (WGAN), are constructed which consist of 2 deep convolutional neural networks (CNN) namely, a discriminator and a generator.
Technical Paper

Biologically Inspired, Intelligent Muscle Material for Sensing and Responsive Delivery of Countermeasures

The design and development of new biologically inspired technologies based on intelligent materials that are capable of sensing the levels of target biomolecules and, if needed, trigger appropriate countermeasures to regulate biological processes and rhythms of the astronauts is being undertaken in our laboratories. This is accomplished by coupling biologically inspired sensors that monitor the levels of the target biomolecules with intelligent polymeric materials that can regulate the release of a countermeasure. The technology developed here integrates sensors and artificial muscle material into a self-regulating device that can perform with minimal crew intervention. Further, it takes advantage of microfabrication technology to construct lightweight and robust responsive delivery systems. These “intelligent” devices address the need for the control and regulation of biological processes and rhythms under spaceflight conditions.
Technical Paper

Comparison of Intermediate-Combustion Products Formed in Engine with and without Ignition

RESULTS of tests performed on a modified type F-4 CFR engine show that precombustion reactions in both the fired and motored engine gave the same carbonyl products. The maximum specific yields of these carbonyls were similar for a given fuel compressed with comparable pressure-time-temperature histories in both motored- and fired-engine tests. As the motored engine seems to duplicate precombustion reactions occurring in a fired engine under normal operating conditions, the authors of this paper conclude that the motored engine, offering ease of control and sampling, is a convenient and valid tool for combustion research.
Journal Article

Design of a Parallel-Series PHEV for the EcoCAR 2 Competition

The EcoCAR 2: Plugging into the Future team at the Ohio State University is designing a Parallel-Series Plug-in Hybrid Electric Vehicle capable of 50 miles of all-electric range. The vehicle features a 18.9-kWh lithium-ion battery pack with range extending operation in both series and parallel modes made possible by a 1.8-L ethanol (E85) engine and 6-speed automated manual transmission. This vehicle is designed to drastically reduce fuel consumption, with a utility factor weighted fuel economy of 75 miles per gallon gasoline equivalent (mpgge), while meeting Tier II Bin 5 emissions standards. This report details the rigorous design process followed by the Ohio State team during Year 1 of the competition. The design process includes identifying the team customer's needs and wants, selecting an overall vehicle architecture and completing detailed design work on the mechanical, electrical and control systems. This effort was made possible through support from the U.S.
Journal Article

Development of Refined Clutch-Damper Subsystem Dynamic Models Suitable for Time Domain Studies

This study examines clutch-damper subsystem dynamics under transient excitation and validates predictions using a new laboratory experiment (which is the subject of a companion paper). The proposed models include multi-staged stiffness and hysteresis elements as well as spline nonlinearities. Several example cases such as two high (or low) hysteresis clutches in series with a pre-damper are considered. First, detailed multi-degree of freedom nonlinear models are constructed, and their time domain predictions are validated by analogous measurements. Second, key damping sources that affect transient events are identified and appropriate models or parameters are selected or justified. Finally, torque impulses are evaluated using metrics, and their effects on driveline dynamics are quantified. Dynamic interactions between clutch-damper and spline backlash nonlinearities are briefly discussed.
Technical Paper

Development of Virtual Fuel Economy Trend Evaluation Process

With the advancement of the autonomous vehicle development, the different possibilities of improving fuel economy have increased significantly by changing the driver or powertrain response under different traffic conditions. Development of new fuel-efficient driving strategies requires extensive experiments and simulations in traffic. In this paper, a fuel efficiency simulator environment with existing simulator software such as Simulink, Vissim, Sumo, and CarSim is developed in order to reduce the overall effort required for developing new fuel-efficient algorithms. The simulation environment is created by combining a mid-sized sedan MATLAB-Simulink powertrain model with a realistic microscopic traffic simulation program. To simulate the traffic realistically, real roads from urban and highway sections are modeled in the simulator with different traffic densities.
Technical Paper

Development of the Design of a Plug-In Hybrid-Electric Vehicle for the EcoCAR 3 Competition

The design of a performance hybrid electric vehicle includes a wide range of architecture possibilities. A large part of the design process is identifying reasonable vehicle architectures and vehicle performance capabilities. The Ohio State University EcoCAR 3 team designed a plug-in hybrid electric vehicle (PHEV) post-transmission parallel 2016 Chevrolet Camaro. With the end-goal of reducing the environmental impact of the vehicle, the Ohio State Camaro has been designed with a 44-mile all-electric range. It also features an 18.9 kWh Li-ion energy storage system, a 119 kW 2.0L GDI I4 engine that runs on 85% ethanol (E85) fuel, a 5-speed automated manual transmission, and a 150 kW peak electric machine. This report details the design and modeling process followed by the Ohio State team during Year 1 of the competition. The process included researching the customer needs of the vehicle, determining team design goals, initial modeling, and selecting a vehicle architecture.
Journal Article

Driver’s Response Prediction Using Naturalistic Data Set

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.
Technical Paper

Estimation of Cutting Parameters in Two-Stage Piercing to Reduce Edge Strain Hardening

Edge fracture is a common problem when forming advanced high strength steels (AHSS). A particular case of edge fracture occurs during a collar forming/hole extrusion process, which is widely used in the sheet metal forming industry. This study attempts to relate the edge stretchability in collar forming to the strain hardening along the pierced edge; thus, Finite Element (FE) simulations can be used to reduce the number of experiments required to improve cutting settings for a given material and thickness. Using a complex-phase steel, CP-W 800 with thickness of 4.0 mm, a single-stage piercing operation is compared with a two-stage piercing operation, so called shaving, in terms of strains along the pierced edge, calculated by FE simulation. Results indicated that strains were reduced along the pierced edge by shaving.
Technical Paper

Estimation of Wet Clutch Friction Parameters in Automotive Transmissions

In this paper, a new algorithm for the off-line estimation of wet clutch friction parameters is proposed for automotive transmissions, motivated by the usefulness of such an algorithm for diagnosing the condition of the clutch and transmission fluid in service. We assume that clutch pressure is measured, which is the case in dual clutch transmissions (DCT). The estimation algorithm uses measured rotational speeds and estimated accelerations at the input and output sides of a clutch, measured clutch pressures, and a simplified dynamic model of clutch friction to estimate the viscous and contact components of clutch friction torque. Coefficient of friction data is generated using the contact friction torque. A Stribeck friction model is fit to the data, and parameters in the model are then calculated by applying linear least squares estimation.
Technical Paper

Experimental Investigation on Surge Phenomena in an Automotive Turbocharger Compressor

Downsizing and turbocharging are today considered an effective way to reduce CO2 emissions in automotive gasoline engines, especially for the European and US markets. In the broad field of research and development for engine boosting systems, the instability phenomenon of surge has gathered considerable interest in recent years, as the main limiting factor to high performance boosting and boost pressure control. To this extent, developing an in-depth knowledge of the surge dynamics and on the phenomena governing the transition from stable to unstable operation can provide very valuable information for the design of the intake system and boost pressure control algorithms, allowing optimal boost pressure without compromising the transient response.
Technical Paper

FMVSS 126 Sine with Dwell ESC Regulation Test for Autonomous Vehicles

Electronic stability control (ESC) has been an essential part of road vehicle safety for almost three decades. In April of 2007, the United States federal government issued a regulation to test the validity of ESC in development vehicles, and the regulation is called Federal Motor Vehicle Safety Standards (FMVSS) 126 in North America (NA), and an equivalent test in other countries outside of NA called ECE13-H (Economic Commission for Europe). While these standards have been used to certify ESC in development passenger cars for over a decade, this has not yet been scrutinized for the application of autonomous vehicles. Autonomous cars have sensors and control systems which can be used to improve ESC, where commercial standard vehicles do not.
Journal Article

Fast Simulation of Wave Action in Engine Air Path Systems Using Model Order Reduction

Engine downsizing, boosting, direct injection and variable valve actuation, have become industry standards for reducing CO2 emissions in current production vehicles. Because of the increasing complexity of the engine air path system and the high number of degrees of freedom for engine charge management, the design of air path control algorithms has become a difficult and time consuming process. One possibility to reduce the control development time is offered by Software-in-the-Loop (SIL) or Hardware-in-the-Loop (HIL) simulation methods. However, it is significantly challenging to identify engine air path system simulation models that offer the right balance between fidelity, mathematical complexity and computational burden for SIL or HIL implementation.
Technical Paper

Flight Investigation of Natural Laminar Flow on the Bellanca Skyrocket II

Two major concerns have inhibited the use of natural laminar flow (NLF) for viscous drag reduction on production aircraft. These are the concerns of achieveability of NLF on practical airframe surfaces, and maintainability in operating environments. Previous research in this area left a mixture of positive and negative conclusions regarding these concerns. While early (pre-1950) airframe construction methods could not achieve NLF criteria for waviness, several modern construction methods (composites for example) can achieve the required smoothness. This paper presents flight experiment data on the achieveability and maintainability of NLF on a high-performance, single-propeller, composite airplane, the Bellanca Skyrocket II. The significant contribution of laminar flow to the performance of this airplane was measured. Observations of laminar flow in the propeller slipstream are discussed, as are the effects of insect contamination on the wing.
Technical Paper

High Speed Ridged Fasteners for Multi-Material Joining

Automobile manufacturers are reducing the weight of their vehicles in order to meet strict fuel economy legislation. To achieve this goal, a combination of different materials such as steel, aluminum and carbon fiber composites are being considered for use in vehicle bodies. The ability to join these different materials is an ongoing challenge and an area of research for automobile manufacturers. Multiridged fasteners are a viable option for this type of multi-material joining. Commercial systems exist and are being used in the industry, however, new ridged nail designs offer the potential for improvement in several areas. The goal of this paper is to prototype and test a safer flat-end fastener whilst not compromising on strength characteristics, to prevent injury to factory workers. The nails were prototyped using existing RIVTAC® nails.
Technical Paper

Integrated Computational Materials Engineering (ICME) Multi-Scale Model Development for Advanced High Strength Steels

This paper presents development of a multi-scale material model for a 980 MPa grade transformation induced plasticity (TRIP) steel, subject to a two-step quenching and partitioning heat treatment (QP980), based on integrated computational materials engineering principles (ICME Model). The model combines micro-scale material properties defined by the crystal plasticity theory with the macro-scale mechanical properties, such as flow curves under different loading paths. For an initial microstructure the flow curves of each of the constituent phases (ferrite, austenite, martensite) are computed based on the crystal plasticity theory and the crystal orientation distribution function. Phase properties are then used as an input to a state variable model that computes macro-scale flow curves while accounting for hardening caused by austenite transformation into martensite under different straining paths.
Technical Paper

Model Order Reduction for x-In the Loop (xIL) Simulation of Automotive Transmissions

Increasing complexity of automotive systems along with growing safety and performance requirements, is causing development cycle costs to swell. A common solution is to use a Model-Based Design (MBD) approach, particularly using x-In the Loop (xIL) simulation methods for Validation and Verification (V&V). MBD allows efficient workflow from offline control design using high-fidelity models to real time V&V using Hardware-in-the-Loop (HIL) simulations. It is very challenging to reduce the complex non-linear high-fidelity models to real-time capable models for HIL simulation. Current literature does not provide a standard approach for obtaining the HIL-capable reduced model for complex non-linear systems. In this paper we present an approach to perform model reduction in light of HIL-level requirements. The approach is presented using an example of a 10-speed automatic transmission. The system constitutes three subsystems - the hydraulic network, mechanical gearbox, and torque converter.
Technical Paper

Model and Controls Development of a Post-Transmission PHEV for the EcoCAR 3 Competition

The Ohio State University EcoCAR 3 team is designing a plug-in hybrid electric vehicle (PHEV) post-transmission parallel 2016 Chevrolet Camaro. With the end-goal of reducing the environmental impact of the vehicle, the Ohio State Camaro has been designed to have a 44-mile all-electric range. The vehicle is to consist of an 18.9 kWh Li-ion energy storage system, a 119 kW 2.0L GDI I4 engine that runs on 85% ethanol (E85) fuel, a 5-speed automated manual transmission, and a 150 kW peak-power electric machine. This report details the model and controls development process followed by the Ohio State team during Year 1 of the EcoCAR 3 competition. The focus of the paper will be on overall development of a vehicle model, initial simulation results, and supervisory controls development. Finally, initial energy consumption results from the model and future improvements will be discussed.