Master of Science, The Ohio State University, 2013, Mechanical Engineering

The purpose of this thesis is to evaluate the findings brought forth from a research project conducted at The Ohio State University Center for Automotive Research. The objective of the research was to accurately model a 6x4 tractor-trailer rig using TruckSim and simulate severe braking and handling maneuvers with hardware in the loop and software in the loop simulations. For the hardware in the loop simulation (HIL), the tractor model was integrated with a 4s4m anti-lock braking system (ABS) and straight line braking tests were conducted. In addition to this, CAN messages were transmitted and received with the electronic control unit utilized by the ABS system. For the software in the loop simulation (SIL), anti-lock braking (ABS) and roll stability control (RSC) algorithms were developed using Simulink and tested with the TruckSim model. By properly simulating the tractor-trailer rig using HIL and SIL simulations, severe maneuvers could be performed and the rig's response characteristics could be evaluated within a lab environment. The first step in creating the HIL and SIL simulations was to develop a model of a 6x4 tractor using TruckSim. In order to accomplish this, over 100 vehicle parameters were acquired from a real production tractor and entered into TruckSim. Similarly, parameters from a production trailer were acquired and entered as well. By entering these parameters into TruckSim, the dynamic behavior of the actual tractor-trailer could be simulated within a computer environment. The tractor-trailer model was then subjected to simple handling maneuvers without the aid of any vehicle stability controls and its performance was compared against experimental data from the tractor manufacturer. This was done in order to validate the accuracy of the TruckSim model. After the tractor-trailer model was validated, the HIL simulation was developed. Essentially, the HIL simulation integrates actual braking hardware with the computer based tractor mod (open full item for complete abstract)

Committee: Dennis Guenther Dr. (Advisor); Gary Heydinger Dr. (Advisor) Subjects: Automotive Engineering; Engineering; Mechanical Engineering

Master of Science, The Ohio State University, 2021, Mechanical Engineering

With the integration of Advanced Driver Assistance Systems (ADAS) and Intelligent Transportation Systems into vehicles, the need to measure the performance of these systems from a large scale traffic system level to vehicle component level is necessary in order to ensure the safety of the driver and all the traffic elements like pedestrians, other vehicles and infrastructure. Due to the practical constraints, software-in-loop (SiL) is the widely adopted methodology over on-road testing for verification and validation of these systems. However, these SiL solutions can be expensive and limited in their capabilities due to their proprietary nature. The unavailability of an open-sourced toolset for simulating microscopic vehicles at a macroscopic level has motivated the creation of a novel Simulation of Urban MObility based framework which can be used as a platform for system integration and co-simulations with other tools. Another problem addressed in this thesis is in the rapidly developing area of Perception System Algorithms. Due to the increased availability of data, these algorithms are being trained on huge datasets. However, due to the unavailability of proper evaluation methods or limited traditional metrics, it is challenging to evaluate the variation in the performance of these algorithms on images subjected to environmental variations. In order to evaluate the variation of the performance of an algorithm in different lighting conditions, a novel sensitivity based approach is proposed in this thesis.

Committee: Punit Tulpule (Advisor); Benjamin Yurkovich (Committee Member); Marcello Canova (Committee Member) Subjects: Automotive Engineering; Mechanical Engineering

Master of Science, The Ohio State University, 2020, Mechanical Engineering

The objective of this work is to benchmark Advanced Driver Assistance Systems (ADAS) using a limited motion Driver-in-the-Loop (DiL) Simulator and Model Predictive Control (MPC). These ADAS features include Adaptive Cruise Control (ACC), Lane Keeping Assist (LKA), Forward Collision Warning (FCW), and Automatic Emergency (AEB). The handoff of these features is at the discretion of the driver but maintains the operational design domain. Simplified internal models for the ACC MPC and LKA MPC are presented, so the MPC toolbox CasADi could be used as Software-in-the-Loop (SiL). Both MPC's leverage adaptive linear techniques alleviating the inherent nonlinearities. SiL ensures robust, real-time execution of the features integrating with the simulator. Regulators and automotive manufacturers are tasked with eliminating automotive deaths and injuries. Of active safety tools at their disposal, ADAS features provide a promising ability to aiding this cause. Driving simulators are becoming an important development tool for active safety systems, automated driving features, and vehicle dynamics development. This driving simulator couples SCANeR Studio®, CarSim®, and MATLAB/Simulink®. Refined and custom cues give the driver a sense of the virtual world providing the immersion. Offline verification using the testbed and sample results using the driving simulator shows the efficacy of prototyping and evaluating ADAS features using the simulator. Combining these elements allows for both quantitative and qualitative assessment of the systems' functionality, performance, and safety assurance.

Committee: Giorgio Rizzoni (Advisor); Qadeer Ahmed (Committee Member); Jeffrey Chrstos (Committee Member) Subjects: Mechanical Engineering

Master of Science, The Ohio State University, 2013, Mechanical Engineering

The work presented within this thesis consists of the validation of a supervisory controller and vehicle simulator for the ECO Saver IV demonstration bus being developed as part of the National Fuel Cell Bus Program (NFCBP). The goal of the NFCBP is to develop fuel cell transit buses such that a U.S. industry for fuel cell bus technology can be established through both technology innovation and increased public awareness of fuel cell vehicles. The use of fuel cells in vehicles is desirable due to their high efficiencies and zero emissions, allowing the transportation sector to rely less heavily on petroleum and carbon based fuels that emit hazardous greenhouse gases. The ECO Saver IV, as designed by the DesignLine Corporation through a contract with the Center for Transportation and the Environment, is a battery dominant fuel cell hybrid bus that takes advantage of the benefits of hybridization in conjunction with the benefits of the fuel cell. The team of researchers at The Ohio State University (OSU) Center for Automotive Research (CAR) served as a subcontractor to develop a supervisory controller and fuel cell hybrid bus simulator, modeled after the chosen powertrain architecture. The validation performed involved the use of software-in-the-loop and hardware-in-the-loop simulations, where the results were compared to baseline model-in-the-loop simulations. The driving conditions of the intended application of the demonstration bus, i.e., integration into the OSU Campus Area Bus Services (CABS) fleet, were taken into consideration through the development of real-world drive cycles that were representative of actual CABS bus routes. A new driver model was developed that solved issues related to tracking distance, velocity and road grade to enable the use of real-world drive cycles. The results of the validation are to be used in the final phases of development and construction of the ECO Saver IV fuel cell hybrid transit bus to prove the effectiveness of (open full item for complete abstract)

Committee: Shawn Midlam-Mohler Dr. (Advisor); Yann Guezennec Dr. (Committee Member) Subjects: Automotive Engineering; Engineering; Mechanical Engineering

Master of Science, The Ohio State University, 2013, Mechanical Engineering

The purpose of this thesis is to develop a vehicle dynamics model of a 6 X 4 cab-over tractor and a 2-axle semitrailer combination and a model-based design of ABS and ESC controllers. In addition to this, a Hardware-in-the-Loop (HIL) simulation of an Anti-lock Braking System (ABS) for a heavy truck was performed using dSPACE. TruckSim, developed by Mechanical Simulation Corporation (MSC), was used to model the vehicle dynamics. The tractor was equipped with disc brakes and the trailer was equipped with drum brakes. Model validation was by performing various dynamic maneuvers like J-turn, double lane change, decreasing radius curve test, high dynamic steer input and constant radius test with increasing speed. The model was validated in all three loading conditions: Bobtail or solo tractor, low CG trailer and high CG trailer condition. The vehicle responses obtained from TruckSim were compared against the experimental field test data obtained from the Heavy Truck Manufacturer (HTM). A hardware-in-the-loop (HIL) simulation of a heavy truck ABS system was setup in order to better understand the ABS control strategy and various activation thresholds involved. The test bench consists of six (6) brake chambers, ABS modulator valves, ABS electronic control unit from a commercial supplier, two air reservoirs, wheel speed sensors and pressure sensors for measuring the individual brake chamber pressures. dSPACE midsize was used to interface the vehicle model in TruckSim with the hardware components in the physical realm. The simulator converts the digital signals from TruckSim such as lateral acceleration, yaw rate and tractor speed into suitable analog signals which serve as inputs to the control module. For this simulation, the wheel speed signals coming from TruckSim were converted into an analog signal of sinusoidal form whose frequency is proportional to the wheel spin rate. TruckSim along with the hardware components thus forms a closed-loop system. The algorithm in (open full item for complete abstract)

Committee: Dennis Guenther PhD (Advisor); Gary Heydinger PhD (Committee Member) Subjects: Automotive Engineering; Mechanical Engineering

Master of Science, The Ohio State University, 2013, Nuclear Engineering

A hardware-in-the-loop model was developed to represent digital sensing and control of steam generator water-level. The model was created with an intention to serve as a component within a larger, distributed digital systems conceptual testing facility. In the present application, a software model simulates a nuclear pressurized water reactor core, and the core is cooled by a hardware and software model of a Westinghouse U-tube steam generator. The present application is configured using plant specifications consistent with “Plant X”. Software was written in C++¿¿, and hardware components include Phidgets and Measurement Computing digital input-output modules, proportional solenoid valves, a PC cooling pump, and gear pumps. This model assumes perfect implementation of sliding average-core-temperature control. During plant startup or normal operation, plant power precisely determines all steam flow characteristics. Liquid water simulates secondary coolant flow. Water pumped from a tank simulates steam, and recuperating feed water responds to subsequent level readings. Level readings as a function of plant power are measured and lie within the alarm-free region of the narrow range (+/-5% of the level set point). This design has been developed for incorporation within a distributed hardware/software component within a digital systems conceptual testing facility for digital systems testing by network-distributed control.

Committee: Carol Smidts PhD (Advisor); Tunc Aldemir PhD (Committee Member) Subjects: Engineering; Nuclear Engineering