Terms:
SAE International Journal of Commercial Vehicles
AND
4
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

The Development of New Hino Hybrid Commercial Vehicles

SAE International Journal of Commercial Vehicles

Hino Motors, Ltd-Shigeru Suzuki
  • Journal Article
  • 2011-01-2196
Published 2011-09-13 by SAE International in United States
In 1991, Hino Motors, Ltd. (Hino) launched the world's first hybrid city buses in the market. Thereafter, Hino has improved its hybrid vehicle technology and applied it to various commercial vehicles including city buses, sightseeing buses, medium-duty trucks and light-duty trucks. Recently, Hino has developed light-duty hybrid trucks, whose fuel efficiency has improved by 50% relative to its Diesel trucks. The significant improvement in fuel efficiency is achieved by four improvements in hybrid trucks. First, the hybrid system is improved: the change in the drive train layout, the relocation of a clutch, makes it possible to recoup the regenerative energy more efficiently. Second, the vehicle is also improved by the new hybrid engine, the reduction of the rotation speed of the engine during idling, and the improvement in the differential gear ratio. Third, new hybrid system controls are developed to bring benefits of the hybrid system to all drivers. Forth, low-cost but efficient units are developed to make fuel efficient hybrid vehicles prevail in the market. This paper discusses new Hino hybrid vehicle technologies developed…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Steering Effects Upon Lateral Dynamics of a SUV On Deformable Surfaces

SAE International Journal of Commercial Vehicles

Lublin University of Technology-Jaroslaw Pytka
  • Journal Article
  • 2011-01-2159
Published 2011-09-13 by SAE International in United States
We studied the effect of steering dynamics on lateral dynamics for a 1.6 ton 4x4 sport utility vehicle (SUV) on deformable surfaces. The vehicle used for the outdoor tests was equipped with (1) a steering robot to apply repeatable steering wheel excitations and (2) a high-precision differential GPS (DGPS) system to gather physical measures that describe lateral dynamics: lateral acceleration, yaw rate, and vehicle sideslip angle. The vehicle was driven over three different deformable surfaces~a loess and a sandy soil and wet snow~with a constant speed of 10 km/h. The steering robot applied inputs of (1) sine wave excitation at 0.5, 1.0, and 2.5 Hz, and (2) ramp change (or trapezoidal) excitation with steering wheel rate at 100, 500, and 1500 deg/s. Results are presented as frequency paths and time courses to analyze effects of surface and steering dynamics. Data from ramp change input excitation tests were used to derive factors describing lateral vehicle dynamics: yaw rate gain, peak response time, and TB factor. We concluded that the test method was sensitive enough to analyze…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Semitrailer Torsional Stiffness Data for Improved Modeling Fidelity

SAE International Journal of Commercial Vehicles

Ohio Northern University-David R. Mikesell
SEA Limited-Ashley Dunn, Gary J. Heydinger
  • Journal Article
  • 2011-01-2163
Published 2011-09-13 by SAE International in United States
Vehicle dynamics models employed in heavy truck simulation often treat the semitrailer as a torsionally rigid member, assuming zero deflection along its longitudinal axis as a moment is applied to its frame. Experimental testing, however, reveals that semitrailers do twist, sometimes enough to precipitate rollover when a rigid trailer may have remained upright. Improving the model by incorporating realistic trailer roll stiffness values can improve assessment of heavy truck dynamics, as well as an increased understanding of the effectiveness of stability control systems in limit handling maneuvers.Torsional stiffness measurements were conducted by the National Highway Traffic Safety Administration (NHTSA) for eight semitrailers of different types, including different length box vans, traditional and spread axle flat beds, and a tanker. Known moments were applied to the front of each trailer while the trailer twist angle was measured at various locations along the length of the trailer. Suspension stiffness, trailer body stiffness, and overall stiffness results were tabulated for all types.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Model for Combined Tire Cornering and Braking Forces with Anisotropic Tread and Carcass Stiffness

SAE International Journal of Commercial Vehicles

ASCL,Jilin University-Konghui Guo, Nan Xu, Dang Lu, Jie Yang
  • Journal Article
  • 2011-01-2169
Published 2011-09-13 by SAE International in United States
The objective of this paper is to enhance the accuracy of tire model combined tire cornering and braking forces with anisotropic tread and carcass stiffness. The difference of tire longitudinal slip stiffness and cornering stiffness will arouse that the direction of tire resultant shear stress in adhesion region is not the same as that in sliding region. Then the direction of total friction force in the whole tire-road contact patch will change under different combined cornering/braking situations.Generally speaking, there is a basic premise: “the direction of resultant shear stress in sliding region will be the same as that in adhesion region” in the existing tire models, in which the anisotropy of tread and carcass stiffness is neglected. Therefore, these models don't work well when the tire tread and carcass stiffness has a strong anisotropy.The direction of tire shear stress in the adhesion and the sliding region of the contact patch is discussed in this paper and a modification factor is proposed basing on the UniTire semi-physical model to modify the direction of resultant shear stress,…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

New Attempts on Vehicle Suspension Systems Modeling and Its Application on Dynamical Load Analysis

SAE International Journal of Commercial Vehicles

Georgia Institute of Technology-Jin Huang
Hunan University-Qingmin Huang, Aiguo Cheng
  • Journal Article
  • 2011-01-2171
Published 2011-09-13 by SAE International in United States
Suspension system dynamics can be obtained by various methods and vehicle design has gained great advantages over the dynamics analysis. By employing the new Udwadia-Kalaba equation, we endeavor some attempts on its application to dynamic modeling of vehicle suspension systems. The modeling approach first segments the suspension system into several component subsystems with kinematic constraints at the segment points released. The equations of motion of the unconstrained subsystems are thus easily obtained. Then by applying the second order constraints, the suspension system dynamics is then obtained. The equations are of closed-form. Having the equations obtained, we then show its application on dynamical load analysis. The solutions for the dynamical loads at interested hard points are obtained. We use the double wishbone suspension to show the systematic approach is easy handling.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Gear Rattle Noise Prediction from Dynamic Simulation

SAE International Journal of Commercial Vehicles

John Deere India Pvt. Ltd.-Amit J Bora
John Deere, USA-Robert White, Dalsang Chaudhari
  • Journal Article
  • 2011-01-2242
Published 2011-09-13 by SAE International in United States
Gear rattle noise is a common issue in manual gear transmissions and is often difficult to resolve. This paper discusses a methodology involving development of a simulation model for noise prediction and subsequent design of experiments (DOE) analysis to select optimal design parameters to reduce rattle noise. A one-dimensional torsional vibration simulation model for a tractor driveline was developed and was correlated with experimental measurements. This correlated model was used to calculate the torque variation between the gear pairs based on engine excitations. The standard deviation of this mesh torque was used as a metric and was correlated to noise ratings assigned by experts during experimental evaluation. Using this metric as the response variable, a DOE was conducted to determine the contributing factors and their influence on the rattle noise. Optimal design parameters were selected to achieve target value on the rattle metric. Physical prototype was built using these optimized parameters and was validated against noise ratings assigned by experts. It was found to successfully satisfy the subjective rattle criterion.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Soil Stress State Under Loads of Commercial Vehicles

SAE International Journal of Commercial Vehicles

Lublin University of Technology-Jaroslaw Pytka
  • Journal Article
  • 2011-01-2173
Published 2011-09-13 by SAE International in United States
The paper contains experimental results of soil stress state under loading of commercial wheeled vehicles. The measurements were performed with the use of SSTs (Stress State Transducers), which enable to determine soil pressures needed for calculations of stress state at a point: principal stresses and their direction cosines as well as octahedral stresses. A detailed description of the measuring method with an introductory theory of operation of the SST together with some methodology aspects of soil pressure measurements are included. The field tests were conducted on three different soil surfaces: loess, sand and turf as well as on snow surface in winter conditions. For the tests, two vehicles were used: a 5,6T 4x4 truck and a 14T 6x6 truck. The vehicles were driven at constant low speed or at different speeds. Moreover, effects of wheel loading, reduced inflation pressure, drive modes (rolling or driving) were also analyzed. The results are presented partially in a form of stress courses and as numerical data of peak maximum stresses under wheels.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Drag Reduction of a Modern Straight Truck

SAE International Journal of Commercial Vehicles

Old Dominion Univ-Drew Landman, Matthew Cragun, Mike McCormick
Solus-Solutions and Technologies-Richard Wood
  • Journal Article
  • 2011-01-2283
Published 2011-09-13 by SAE International in United States
A wind tunnel test program was conducted at the Langley Full Scale Tunnel (LFST) to evaluate the performance of five passive drag reduction configurations on a modern straight truck at full scale. Configurations were tested in a build-up fashion with results representing a cumulative effect. Tested configurations include a front valance, a front box fairing, a boat-tail, an ideal side-skirt, and a practical side-skirt. Configurations were evaluated over a nominal 9 degree yaw sweep to establish wind averaged drag coefficients using SAE J1252. Genuine replicate yaw sweeps were used in an uncertainty analysis. Results show up to 28% improvement in wind-averaged drag coefficient and that significant gains can be made in straight truck fuel economy, even at non-highway speeds.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Tire Wear Improvement by Steering a Third Axle

SAE International Journal of Commercial Vehicles

TRW Commercial Steering Systems-Daniel Williams
  • Journal Article
  • 2011-01-2148
Published 2011-09-13 by SAE International in United States
The conventional rear tandem axle of a three-axle vehicle produces a yaw resisting moment that adversely impacts vehicle performance. This work examines the effect of steering the rear axle on tire wear. Using actual vehicle test data, a tire wear model is developed. This tire wear model is then used to predict tire wear savings over an actual commercial vehicle duty cycle when the rear axle is steered. The result of this projection is shown to be consistent with reported third party field experience.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Balance of Static and Dynamic Rollover Thresholds for a Three-Axle Vehicle

SAE International Journal of Commercial Vehicles

Oshkosh Corporation-Xiaobo Yang
  • Journal Article
  • 2011-01-2152
Published 2011-09-13 by SAE International in United States
In this study, a three-axle vehicle model established with ADAMS/Car is first correlated with field test data from quasi-static tilt table and highly dynamic NATO double lane change maneuver tests, respectively. It is then applied to predict the vehicle static rollover threshold (SRT) and dynamic rollover threshold (DRT). With the optimization approach proposed in this study it is possible to efficiently tune the anti-roll bar stiffness at each axle, to either maximize SRT or DRT, or balance both. The sensitivity results derived from the optimization iteration process can be applied to effectively size the three anti-roll bars that balance the static and dynamic roll stability performances. The proposed method can be potentially applied to include other parameters to address the roll stability issues and beyond.
Annotation ability available