M.Sc Thesis


M.Sc StudentGalia Pinsler
SubjectA New Approach to Definition of Safety Regions for a Test-
Field
DepartmentDepartment of Aerospace Engineering
Supervisors Professor Iosilevskii Gil
Full Professors Ben-Asher Yoseph


Abstract

Operational tests of high damage potential weapons may present danger to the civil population. In order to make the associated risks acceptable, the weapons are invariable equipped with destruction mechanisms, which allow the safety team on the ground to destroy the weapon during the test.

Since thousands of simulations are needed in order to set the destruction criteria, full 6 degrees of freedom (DOF) simulations are impractical at current computer capabilities. At present, they are invariably replaced by 3DOF simulations. In the current model the missile is represented by a point mass whose degrees of freedom are its location in space, disregarding its body angles. The remaining 3DOF are pre-set by simple models.  The angle of attack is assumed to 'jump' upon the failure to its maximal allowable value.

The research hypothesis is that this assumption is too strict resulting in the reduction of the allowable weapon deviations from its nominal trajectory up to the point where - according to 3DOF simulations - no safe test can be conducted at all.

In this work it is suggested to increase number of degrees of freedom in simulations to four, supplementing the 3 coordinates of the weapon center of mass by its angle of attack.

The 4DOF simulations have been compared with the existing 3DOF simulations as well as with full 6DOF simulations.

The analysis supports the research assumption that the 4DOF simulations indeed improve the accuracy of the simulations and increase the allowable deviations of the weapon from its nominal trajectory.