Incorporating Control into the Optimal Structural Design of Large Flexible Space Structures.
Abstract
An eigenspace optimization approach is used to incorporate optimal control into the structural design process for large flexible space structures. The equations of motion for an uncontrolled system are developed by deriving the kinetic and potential energy for the system and then using assumed modes to discretize the energies. These expressions are then linearized, the Lagrangian formed, and lagrange equations written for the system. An existing optimal control law is incorporated to form the equations of motion for the controlled system. A parameter optimization technique is used to minimize the mass of the Draper/RPL configuration model involving eigenspace optimization. A computer algorithm is developed that effectively optimizes a global structural parameter vector to minimize the mass of the model, while constraining specified eigenvalues. The eigenvalue sensitivities are passed to a constrained function minimization program called CONMIN which minimizes the mass of the appendages. The constraints imposed restrict the first eigenvalue to the left half plane and the natural frequency of the third eigenvalue to a specified stable region. The result is an algorithm that incorporates an existing optimal control law into the structural optimization process. Originator-supplied keywords-included: Flexible Space Structures, Eigenspace Optimization, Equations of Motion, Draper/RPL Configuration Model Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1984
- Accession Number
- ADA152858
Entities
People
- T. V. Muckenthaler
Organizations
- Air Force Institute of Technology