Accession Number:

ADA151176

Title:

Development of a Dynamic Finite Element Model for Unrestrained Flexible Structures.

Descriptive Note:

Final rept. 1 Sep 82-30 Jun 84,

Corporate Author:

MARYLAND UNIV COLLEGE PARK DEPT OF AEROSPACE ENGINEERING

Personal Author(s):

• Christensen,E. R.
• Lee,S. W.

Report Date:

1984-10-01

Pagination or Media Count:

145.0

Abstract:

An efficient finite element model and solution technique have been developed for the analysis of unrestrained flexible structures undergoing large elastic deformations coupled with gross nonsteady translational and rotational motions with respect to an inertial reference frame. The nonlinear coupled differential equations resulting from the finite element approximation are integrated timewise using an implicit-explicit split operator numerical integration scheme which treats the stability sensitive terms of the equation implicitly while the rest of the equation is treated explicitly. The motion of simple spacecraft structures consisting of flexible beams attached to rigid masses and including the effect of control forces has been studied using three-node eighteen-degree-of-freedom three dimensional beam elements based on the total Lagrangian description. Additional keywords Space structures Equations of motion Stiffness matrix Flexible spacecraft. Author.

Descriptors:

• *MATHEMATICAL MODELS
• *FINITE ELEMENT ANALYSIS
• *FLEXIBLE STRUCTURES
• SPACECRAFT
• EQUATIONS OF MOTION
• MATRICES(MATHEMATICS)
• DEFORMATION
• STIFFNESS
• ELASTIC PROPERTIES
• NONLINEAR DIFFERENTIAL EQUATIONS
• SOLUTIONS(GENERAL)
• INERTIAL SYSTEMS
• LAGRANGIAN FUNCTIONS

Subject Categories:

• Theoretical Mathematics
• Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE