Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 20 for “"Tractor-Trailer"”.
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Autonomous Tractor-Trailer Stopping and Jackknifing Dynamics
… for passenger cars, developing an autonomous for tractor-trailers is the next step for driverless roads. Tractor-trailers are heavy, large, and have a pivot joint between the tractor and trailer that makes the movement between the two more complicated. The purpose of the research presented here is …
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Optimization Under Uncertainty and Total Predictive Uncertainty for a Tractor-Trailer Base-Drag Reduction Device
… outcome of this research is the design for a 3-D tractor-trailer base-drag reduction device that predicts a 41% reduction in wind-averaged drag coefficient at 57 mph (92 km/h) and that is relatively insensitive to uncertain wind speed and direction and uncertain deflection angles due to mounting …
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Boundary-layer control of bluff bodies with application to drag reduction of tractor-trailer truck configurations
… prism and a 1/12 scale model of a typical tractor-trailer truck configuration show that both the MSBC and fence approaches are promising in reducing the aerodynamic resistance. A kit configuration is proposed for ease of implementation of the concepts on new and existing trailers. Road …
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Tractor-trailer Simulation And The Assessment Of Training Scenarios For City-driving: Skill Building In The Area Of Left And Right Turns
A simulated inner-city training scenario was found to increase skills in the area of turning when compared with a simulated off-track training scenario. To answer this question, two groups of ten participants (5 women and 5 men) were tested using three scripted scenarios focusing on left and right …
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Design and analysis of an active underbody aerodynamic device for tractor trailers
… aerodynamic drag. The underbody region of a tractor-trailer is responsible for up to 30 % of the aerodynamic drag on tractor-trailers, which is the highest drag created by any region on the vehicle. In this study, a novel concept of an active underbody drag reduction device is developed and …
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Fractional Order State Feedback Control for Improved Lateral Stability of Semi-Autonomous Commercial Heavy Vehicles
… scenario. However, with large vehicles such tractor-trailers, the system becomes more complex to control and there is an increased occurrence of instabilities. This research investigates a new control scheme based on fractional calculus as a technique that ensures lateral stability of …
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Hardware in the Loop Simulation of a Heavy Truck Braking System and Vehicle Control System Design
… 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 …
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Regional Analysis of Log Truck Crashes in the United States between 2011 and 2015
… fatal log truck crashes increased by 41%. Log tractor-trailer crashes increased 33% while all tractor-trailer crashes increased by 16%. Our findings reveal sufficient differences between log trucks and other large trucks to justify additional research regarding causation of crashes.
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A computer simulation study of tripod follow-the-leader gait coordination for a hexapod walking machine
… such as the Adaptive Suspension Vehicle. Tractor-trailer style steering is introduced as an effort to tailor steering control for this type of gait. Both gait and steering algorithm are implemented on a color graphics computer simulation for study and comparison with other walking …
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PRECARIOUS WORK EXPERIENCES OF IMMIGRANT TRUCKERS: LABOR PROCESS, NETWORKS, AND ENTREPRENEURSHIP
… segments of trucking in this study: (1) national tractor-trailer trucking, (2) regional tractor-trailer trucking, and (3) local dump trucking. National tractor-trailer trucking attracts a variety of immigrants who tend to leave this “tough” segment after a brief while due to opportunities in the …
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Development of mechanistic rolling resistance model for pavement life cycle assessment
… (GWP). A mechanistic multi-degree-of-freedom tractor-trailer model captures not only complex truck dynamic motion excited by roughness, but also the excess fuel consumption (EFC) caused by road roughness and speed. In general, the truck EFC increases with IRI and speed prior to 65 mph. At …
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Experimental Evaluation of the Dynamic Performance Benefits of Roll Stability Control Systems on A-train Doubles
The ride stability of an A-train 28-foot double tractor trailer when outfitted with different Roll Stability Control (RSC) systems with the same payload and suspension configurations is studied experimentally for various dynamic maneuvers. The primary goal of the study is to determine the effect of …
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Decreasing the cost of hauling timber through increased payload
… axle weight constraints on the payloads of tractor-trailers with varying dimensions and axle configurations. Analysis of scalehouse data found log truck gross weights lower on average than the legal maximum but also highly variable. Eliminating both overloading and underloading would result …
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Evaluating the Effectiveness of Electronic Stability Systems in Reducing Truck Rollovers
… based simulation program, and a real-time tractor-trailer braking rig. The simulations were first run without the ESP enabled to determine the critical speed which will cause the truck to roll, then the same simulation runs were executed with the Bendix stability system enabled to determine …
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A Sociological Analysis of the Cartage Truck Driver's Occupation
… and a half years driving straight trucks and tractor trailer trucks for cartage trucking companies in Bowling Green, Kentucky and Cleveland, Ohio. The importance of such a study of a particular occupation may be clarified through an overview of occupations as a whole. In addition, one must …
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Comparison of Modern Controls and Reinforcement Learning for Robust Control of Autonomously Backing Up Tractor-Trailers to Loading Docks
… path following task of autonomously backing up a tractor-trailer. Starting from random locations and orientations, paths are generated to loading docks with arbitrary pose using Dubins Curves. The combination vehicles can be varied in wheelbase, hitch length, weight distributions, and tire …
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Cooperative Clothoidal-Estimation Based Lane Detection For Vehicle Platooning
… Automated platoons, when activated in tractor trailer convoys, have a high potential of increasing the fuel efficiency and improving the utilization of roadways by allowing more vehicles to share the road at the same time. The increased fuel efficiency translates to lower cost on goods …
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Auto-Calibration of WIM Using Traffic Stream Characteristics
… stream to reference values, using five-axle tractor-trailer configured trucks for comparisons, e.g. Federal Highway Administration (FHWA) Class 9. Parameters of the existing algorithms including the Front Axle Weight (FAW) reference value, the sampling frequency required to update the …
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Development of a Heavy Truck Vehicle Dynamics Model using Trucksim and Model Based Design of ABS and ESC Controllers in Simulink
… 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. …