R3 Technology, Inc

R3 Technology, Inc

Technology

R3 Technology, Inc. also represents client products and capabilities.

BALLISTIC RESEARCH AND MODELING

R3 Technology has developed an analysis procedure for long rod penetrators that is based on using a specific method to estimate the effective flow stress of the target. That flow stress is then used in both the WAPEN (Walker-Anderson Analytical Penetration Model) and a regression-based model. The figure on the lower left shows both models compared to 425 test points that involved a variety of target materials, projectile materials, projectile length-to-diameter ratios varying from 1 to 32, and different projectile scales. Analysis of the 425 points required several minutes on a laptop computer and the regression model took less than 1 second. There is more than 3 orders of magnitude speed improvement, and important consideration when millions of shot lines must be analyzed. The figure on the bottom right shows the regression model curves for various length-to-diameter projectiles and plots a number of data points against the curves. There is still room for improvement and advancements. R3 Technology hopes to continue this effort in the future.

R3 Technology, Inc. Ballistic Data System

EXPLOSIVES RESEARCH AND MODELING

The figure below is a plot of the fit contained in the CONWEP model. This is the model that is contained in programs such as LS-Dyna and Autodyn. If one examines the software, you find that the model is based on high order polynomial regressions (sometimes order of 12 or 13) and that the coefficients often carry 10 or more decimals of “precision”. This is actually a poor way to approximate these functions for several reasons. First, it is not particularly computationally efficient. Second, the functions “blow up” when you get too close or too far from and explosive charge as shown in the figure below. R3 Technology has written a version of the CONWEP process that eliminates six of the CONWEP subroutines, runs faster, and avoids the problems associated with the polynomial regressions as implemented in CONWEP.