Type of Document Dissertation Author Senatore, Carmine URN etd-05112010-000153 Title Prediction of mobility, handling, and tractive efficiency of wheeled off-road vehicles Degree PhD Department Engineering Science and Mechanics Advisory Committee
Advisor Name Title Ross, Shane D. Committee Co-Chair Sandu, Corina Committee Co-Chair Cramer, Mark S. Committee Member Dowling, Norman E. Committee Member Hendricks, Scott L. Committee Member Keywords
- tire soil interaction
- energy efficiency
- tractive efficiency
- tire dynamics
- torque distribution
- fuel economy
- lateral force
- multi pass
Date of Defense 2010-05-03 Availability restricted AbstractOur society is heavily and intrinsically dependent on energy transformation and usage. In a world scenario where resources are being depleted while their demand is increasing, it is crucial to optimize every process. During the last decade the concept of energy efficiency has become a leitmotif in several fields and has directly influenced our everyday life: from light bulbs to airplane turbines, there has been a general shift from pure performance to better efficiency.
In this vein, we focus on the mobility and tractive efficiency of off-road vehicles. These vehicles are adopted in military, agriculture, construction, exploration, recreation, and mining applications and are intended to operate on soft, deformable terrain.
The performance of off-road vehicles is deeply influenced by the tire-soil interaction mechanism. Soft soil can drastically reduce the traction performance of tires up to the point of making motion impossible. In this study, a tire model able to predict the performance of rigid wheels and flexible tires is developed. The model follows a semi-empirical approach for steady-state conditions and predicts basic features, such as the drawbar pull, the driving torque and the lateral force, as well as complex behaviors, such as the slip-sinkage phenomenon and the multi-pass effect. The tractive efficiency of different tire-soil configurations is simulated and discussed. To investigate the handling and the traction efficiency, the tire model is implemented into a four-wheel vehicle model. Several tire geometries, vehicle configurations (FWD, RWD, AWD), soil types, and terrain profiles are considered to evaluate the performance under different simulation scenarios. The simulation environment represents an effective tool to realistically analyze the impact of tire parameters (size, inflation pressure) and torque distribution on the energy efficiency. It is verified that larger tires and decreased inflation pressure generally provide better traction and energy efficiency (under steady-state working conditions). The torque distribution strategy between the axles deeply affects the traction and the efficiency: the two variables can’t clearly be maximized at the same time and a trade-off has to be found.
Filename Size Approximate Download Time (Hours:Minutes:Seconds)
28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access Senatore_C_D_2010.pdf 3.16 Mb 00:14:38 00:07:31 00:06:35 00:03:17 00:00:16indicates that a file or directory is accessible from the Virginia Tech campus network only.
If you have questions or technical problems, please Contact DLA.