ACOSS Eight (Active Control of Space Structures), Phase 2
Abstract
This effort addresses three areas of active structure control/ vibration control: (1) Stability ensuring designs in the presence of modal truncation/inaccurate structural models using a method based on the positivity of operators; (2) On-orbit parameter identification using the maximum likelihood method; and (3) Trade-offs between model reference adaptive control and fixed gain control with and without on-orbit parameter identification and system tuning. Developed a stability ensuring design methodology which does not rely on modal truncation, has only low sensitivity to the exact knowledge of the structures model and, with some modifications, can be extended to non-linear systems. The method yields good performance, but is not necessarily optimal. The maximum likelihood method of parameter identification was studied. Parameter data collected on-orbit could be used to up-date the control model and improve performance. An alternative to explicit parameter identification and subsequent system tuning is direct adaptive control. Trade-offs between parameter identification and tuning versus adaptive controls were coordinated and the results are presented.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1981
- Accession Number
- ADA108629
Entities
People
- Frank C. Tung
- Ralph P. Iwens
- Robert J. Benhabib