Innovative Manufacturing and Structural Analysis of Composite Isogrid Structures for Space Applications
Abstract
The search for lightweight and highly efficient structural components is a continuing process. Reducing the structural weight and improving the load carrying capabilities of these structures will allow designers to add additional capabilities while reducing cost. The basic functions of aerospace structures are to transmit and sustain the applied loads, provide a basic shape and to protect the payload. Shell stiffened structures have been used for many years to fulfill these applications. Most of the airframe components are normally plate or shell type structures. Efficiency dictates that they are stiffened or semi-monocoque in construction. The usual means of stiffening is to use longitudinal stringers and frames or ribs. An alternate approach to stiffening is the concept of isogrid, which employs a repetitive equilateral triangular pattern of ribs. The isotropic property and effective Poisson's ratio around 0.3 enables the isogrid to be mathematically transformed to an equivalent homogeneous material layer 1-2. Isogrids, in general, offer a unique set of advantages: (1) they possess a high stiffness to weight ratio; (2) stiffening results in high effective bending stiffness for circumventing local flutter, vibration and buckling problems; (3) stiffening members are useful for attachment of secondary structures and non-structural items and for the introduction of concentrated or localized loads; and (4) cutouts for access doors and windows are easily incorporated into the design.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2003
- Accession Number
- ADA419868
Entities
People
- Derrick Dean
- Gamaleldin Mohamed
- Hassan Mahfuz
- Mohammed Baseer
- Shaik Jeelani
Organizations
- Tuskegee University