Your Selections

Myers, Thomas T.
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.

Further Analysis of Potential Road/Terrain Characterization Rating Metrics

Systems Technology, Inc.-J. Gavin Howe, Dong-Chan Lee, Jeffrey P. Chrstos, Ole Balling, Thomas T. Myers, R. Wade Allen
U.S. Army TARDEC-David J. Gorsich, Alexander Reid
Published 2005-11-01 by SAE International in United States
The U.S. Army uses the root mean square and power spectral density of elevation to characterize road/terrain (off-road) roughness for durability. This paper describes research aimed toward improving these metrics. The focus is on taking previously developed metrics and applying them to mathematically generated terrains to determine how each metric discerns the relative roughness of the terrains from a vehicle durability perspective. Multiple terrains for each roughness level were evaluated to determine the variability for each terrain rating metric. One method currently under consideration is running a relatively simple, yet vehicle class specific, model over a given terrain and using predicted vehicle response(s) to classify or characterize the terrain.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Analysis of Potential Road/Terrain Characterization Rating Metrics

Systems Technology, Inc.-J. Gavin Howe, Dong-Chan Lee, Jeffrey P. Chrstos, Thomas T. Myers, R. Wade Allen
U.S. Army TARDEC-David J. Gorsich, Alexander Reid
Published 2004-10-26 by SAE International in United States
The U.S. Army uses the root mean square and power spectral density of elevation to characterize road/terrain (off-road) roughness for durability. This paper describes research aimed toward improving these metrics. The focus is on taking previously developed metrics and applying them to mathematically generated terrains to determine how each metric discerns the relative roughness of the terrains from a vehicle durability perspective. Multiple terrains for each roughness level were evaluated to determine the variability for each terrain rating metric. One method currently under consideration is running a relatively simple, yet vehicle class specific, model over a given terrain and using predicted vehicle response(s) to classify or characterize the terrain.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

The Effect of Tire Characteristics on Vehicle Handling and Stability

Systems Technology, Inc-R. Wade Allen, Thomas T. Myers, Theodore J. Rosenthal, David H. Klyde
Published 2000-03-06 by SAE International in United States
Handling and stability problems are typically revealed under limit performance maneuvering conditions where tires are pushed to high slip angles under high normal loading conditions. This paper reviews vehicle dynamics handling and stability models relative to tire characteristics and examines tire testing data obtained under normal and extreme maneuvering conditions. Tire data is normalized according to design characteristics in order to reveal basic maneuvering behavior that is relatively independent of size and construction. Computer simulation analysis is used to demonstrate the influence of tire characteristics on handling and stability.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Vehicle Stability Considerations with Automatic and Four Wheel Steering Systems

Systems Technology, Inc.-R. Wade Allen, Thomas T. Myers, Theodore J. Rosenthal
Published 1993-11-01 by SAE International in United States
Automatic and four wheel steering control laws are often developed from the performance point of view to optimize rapid response. Under linear tire operating conditions (i.e., maneuvering at less than .5g's) both performance and safety conditions can be simultaneously met. Under severe operating conditions, such as might be encountered during crash avoidance maneuvering, tire characteristics can change dramatically and induce directional dynamic instability and spinout. The challenge in automatic and four wheel steering system design is to achieve a compromise between performance and safety.This paper will describe analyses carried out with a validated vehicle dynamics computer simulation that shed some light on the vehicle and control characteristics that influence tradeoffs between performance and safety. The computer simulation has been validated against field test data from twelve vehicles including passenger cars, vans, pickup trucks and utility vehicles. The simulation includes a very complete tire model for representing the effects of skidding under hard maneuvering conditions, and has been shown to properly represent spinout conditions that occurred during the validation field testing.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Downhill Grade Severity Rating System

Systems Technology, Inc. Hawthorne, CA-Walter A. Johnson, Thomas T. Myers, Richard J. DiMarco, R. Wade Allen
Published 1981-11-01 by SAE International in United States
A Grade Severity Rating System (GSRS) was developed as a means for reducing the incidence and severity of truck accidents on downgrades. The ultimate result is a roadside sign at the top of each hill. The sign is tailored to the individual hill and gives a recommended maximum speed (to be held constant for the entire grade descent) for each of several truck weight ranges. This concept represents a major step forward in terms of grade descent safety because it tells the driver what to do directly, rather than giving him information which still requires evaluation under different loading conditions.
Annotation ability available