Validating the Directional Performance of Multi-Wheeled Combat Vehicle Computer Simulation Models

2004 ◽  
Author(s):  
Matthew J. Hillegass ◽  
James G. Faller ◽  
Mark S. Bounds ◽  
Moustafa El-Gindy ◽  
Abhishek S. Joshi
Keyword(s):  
Computer Simulation ◽  
Dynamic Performance ◽  
Field Tests ◽  
Simulation Models ◽  
Computer Simulation Model ◽  
Handling Characteristics ◽  
Power Spectral ◽  
Vehicle Variant ◽  
Combat Vehicle ◽  
Modeling Software

The dynamic performance of a multi-wheeled combat vehicle model specially developed in multi-body dynamics code was validated against measured data obtained on the U.S. Army Aberdeen Test Center’s (ATC) test courses. The multi-wheeled combat vehicle variant that was tested was developed in the modeling software TruckSim from Mechanical Simulation Corporation. Prior to validating the model, the vehicle weights, dimensions, tires and suspension characteristics were measured and referenced in the specially developed computer simulation model. Non-linear measured tire and suspension look-up tables were used in the simulation. The predictions of the vehicle handling characteristics and transient response during lane change at different vehicle speeds were compared with field tests results. Measured and predicted results are compared on the basis of vehicle steering, yaw rates, accelerations and handling diagrams. Statistical methods such as power spectral density, root mean square, skewness, and kurtosis are applied to validate the model. Validation tolerances are defined for each set of statistical results based on ATC’s experience.

Validating the Vertical Dynamic Performance of a Multi-Wheeled Combat Vehicle Computer Simulation Model

2005 ◽  
Author(s):  
Matthew J. Hillegass ◽  
James G. Faller ◽  
Mark S. Bounds ◽  
Moustafa El-Gindy ◽  
Seokyong Chae
Keyword(s):  
Computer Simulation ◽  
Simulation Model ◽  
Dynamic Performance ◽  
Performance Testing ◽  
Simulation Models ◽  
Simulation Software ◽  
Full Scale ◽  
Computer Simulation Model ◽  
Vehicle Model ◽  
Combat Vehicle

Performance testing is an important step in the development of any vehicle model. Generally, full-scale field tests are conducted to collect the dynamic response characteristics for evaluating the vehicle performance. However, with increases in computational power and the accuracy of simulation models, virtual testing can be extensively used as an alternative to the time consuming and costly full-scale tests, especially for severe maneuvers. Validation of the simulation results is critical for the acceptance of such simulation models. In this paper, a methodology for validating the vertical dynamic performance of a virtual vehicle has been discussed. The dynamic performance of a multi-wheeled combat vehicle model specially developed using a multi-body dynamics code was validated against the measured data obtained on the U.S. Army Aberdeen Test Center’s (ATC) test courses. The multi-wheeled combat vehicle variant computer simulation model was developed in TruckSim, a vehicle dynamic simulation software developed by the Mechanical Simulation Corporation. Prior to validating the model, the vehicle weights, dimensions, tires and suspension characteristics were measured and referenced in the specially developed computer simulation model. The data for the tire and suspension characteristics were acquired from the respective leading manufacturers in the form of look-up tables. The predictions of the vehicle vertical dynamics on different road profiles at various vehicle speeds were compared with the field test results. The time domain data for the vertical acceleration at the vehicle center of gravity, pitching, vehicle speed and the suspension/damper displacement were compared to analyze the feasibility of using the computer simulation models to predict the vertical dynamic performance of the vehicle. Based on the results it was found that the particular combat vehicle computer simulation model is capable of predicting the vertical dynamic performance characteristics.

Improving Identifiability in Model Calibration Using Multiple Responses

2011 ◽  
Author(s):  
Paul D. Arendt ◽  
Wei Chen ◽  
Daniel W. Apley
Keyword(s):  
Computer Simulation ◽  
Computer Simulations ◽  
Model Uncertainty ◽  
Simulation Models ◽  
Physical Reality ◽  
Model Parameters ◽  
Computer Simulation Model ◽  
Multiple Responses ◽  
Unknown Parameters ◽  
Sources Of Uncertainty

The use of complex computer simulations to design, improve, optimize, or simply to better understand complex systems in many fields of science and engineering is now ubiquitous. However, simulation models are never a perfect representation of physical reality. Two general sources of uncertainty that account for the differences between simulations and experiments are parameter uncertainty and model uncertainty. The former derives from unknown model parameters, while the latter is caused by underlying missing physics, numerical approximations, and other inaccuracies of the computer simulation that exist even if all of the parameters are known. To obtain knowledge of these two sources of uncertainty, data from computer simulations (usually abundant) and data from physical experiments (typically more limited) are often combined using statistical methods. Statistical adjustment of the computer simulation model to account for the two sources of uncertainty is referred to as calibration. We argue that calibration as it is typically implemented, using only a single response variable, is challenging in that it is often extremely difficult to distinguish between the effects of parameter and model uncertainty. However, many different responses (distinct responses and/or the same response measured at different spatial and temporal locations) are automatically calculated in simulations. As multiple responses generally share a mutual dependence on the unknown parameters, they provide valuable information that can improve identifiability of parameter and model uncertainty in calibration, if they are also measured experimentally. In this paper, we explore the use of multiple responses for calibration.

Laboratory study and computer model development related to gross solids' movement in combined sewers

1996 ◽  
Vol 33 (9) ◽  
pp. 39-47 ◽  
Author(s):  
John W. Davies ◽  
Yanli Xu ◽  
David Butler
Keyword(s):  
Computer Simulation ◽  
Pipe Flow ◽  
Model Development ◽  
Simulation Models ◽  
Laboratory Studies ◽  
Pilot Model ◽  
Sewer Systems ◽  
Flow Quality ◽  
Computer Simulation Models ◽  
Theoretical Considerations

Significant problems in sewer systems are caused by gross solids, and there is a strong case for their inclusion in computer simulation models of sewer flow quality. The paper describes a project which considered methods of modelling the movement of gross solids in combined sewers. Laboratory studies provided information on advection and deposition of typical gross solids in part-full pipe flow. Theoretical considerations identified aspects of models for gross solids that should differ from those for dissolved and fine suspended pollutants. The proposed methods for gross solids were incorporated in a pilot model, and their effects on simple simulations were considered.

Sign in / Sign up

Export Citation Format

Share Document