Accession Number : ADP009072

Title :   Trajectory Pattern Method Applied to a Turreted Weapon System.

Corporate Author : STATE UNIV OF NEW YORK AT STONY BROOK DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Rastegar, J. ; Tu, Q. ; Khorrami, F. ; Mattice, M. ; Coleman, N.

Report Date : SEP 1993

Pagination or Media Count : 6

Abstract : The U.S. Army has built a test fixture called ATB1000 which emulates the types of nonlinearities and flexibilities found on most lightweight turreted weapon systems. In this study, the Trajectory Pattern Method is used to synthesize motion trajectories and generate inverse dynamics model based feedforward actuating signals for the test fixture. The main contribution of the present study is the derivation of the inverse dynamics model of the system in parametric form and synthesizing trajectories for point to point motions such that the resulting actuating torques do not contain the harmonic with frequency of the dominant first natural mode of vibration of the flexible beam representing the cannon. With this trajectory pattern, point to point motions with minimal residual vibration can be accomplished with zero end point jerk. A feedforward controller together with a PD feedback loop is constructed and implemented. Computer simulations of the open-loop response of the system are performed and the effectiveness of the approach is verified experimentally. The extension of this approach to vibration suppression problem is discussed.

Descriptors :   *INTERIOR BALLISTICS, *FLEXURAL PROPERTIES, *PROJECTILES, COMPUTERS, DYNAMICS, FEEDBACK, FREQUENCY, HARMONICS, LIGHTWEIGHT, PATTERNS, RESIDUALS, RESPONSE, SUPPRESSION, TEST FIXTURES, TRAJECTORIES, VIBRATION, WEAPON SYSTEMS, COMPUTERIZED SIMULATION, FIRING TESTS(ORDNANCE).

Subject Categories : Ballistics
      Guns

Distribution Statement : APPROVED FOR PUBLIC RELEASE