Projectile

About: Projectile is a research topic. Over the lifetime, 13047 publications have been published within this topic receiving 115563 citations.

Highly efficient accelerator of dense matter using laser-induced cavity pressure acceleration

Abstract: Acceleration of dense matter to high velocities is of high importance for high energy density physics, inertial confinement fusion, or space research. The acceleration schemes employed so far are capable of accelerating dense microprojectiles to velocities approaching 1000 km/s; however, the energetic efficiency of acceleration is low. Here, we propose and demonstrate a highly efficient scheme of acceleration of dense matter in which a projectile placed in a cavity is irradiated by a laser beam introduced into the cavity through a hole and then accelerated in a guiding channel by the pressure of a hot plasma produced in the cavity by the laser beam or by the photon pressure of the ultra-intense laser radiation trapped in the cavity. We show that the acceleration efficiency in this scheme can be much higher than that achieved so far and that sub-relativisitic projectile velocities are feasible in the radiation pressure regime.

Early Upper Paleolithic Approaches to Bone and Antler Projectile Technology

Abstract: Results of a study of Early Upper Paleolithic bone and antler projectile points indicate that different strategies of design, manufacture, and performance of projectile technology were emphasized throughout the Early Upper Paleolithic. An integrated analysis of morphology and wear, as well as experimentation in the production and use of various Early Upper Paleolithic projectile technologies has demonstrated that, while there is change through time in Early Upper Paleolithic projectile technology, there are considerable similarities among contemporaneous approaches to organic projectile technology. Moreover, while Aurignacian organic projectile technology was the same throughout western Europe, Gravettian organic projectile point design varied among regions.

Simplified Projectile Swerve Solution for General Control Inputs

Abstract: The swerve response of fin- and spin-stabilized projectiles to control mechanism inputs is sometimes not intuitive. This paper seeks to explain the basic parameters that govern the swerve of projectiles excited by control inputs. By modeling the overall effect of a generalized control mechanism as a nonrolling reference frame force applied to a point on the projectile, general expressions for swerve are obtained in terms of basic vehicle parameters. These compact expressions are used to show that maximum swerve response for a fin-stabilized projectile is achieved when the force is applied near the nose of the projectile, whereas maximum swerve response for a spin-stabilized projectile is achieved when the force is applied near the base of the projectile.

Large caliber frangible projectile

Abstract: A large caliber, frangible, training projectile imitates, for training purposes, the corresponding tactical projectile. To enable fragmentation of the training projectile at impact, some embodiments of the frangible projectile are partially or entirely made of a material with a lower yield strength than the material used in the counterpart tactical projectile. Some embodiments of the frangible projectile may include portions that are sectioned, welded, or provided with stress risers. Some embodiments of the frangible projectile may include high density particles suspended in a weaker medium. The fragmentation methods may be applied to the overall mass of the projectile, or to a portion of the projectile.