Asynchronous Digital Regulators
Abstract
This report presents methods for designing and analyzing multirate asynchronous digital controls for linear systems. Multirate digital control is a natural approach for systems with widely-spaced natural frequencies. An asynchronous architecture provides a simple approach for assigning control tasks to distributed processors. Previous multirate design methods required either synchronized samplers or high sample rates. Synchronized samplers produce a system that is periodically time varying. Alternatively, high sample rates simulate a continuous controller. In practice, synchronized implementations and implementations with high sample rates may have higher cost, complexity, and weight and lower reliability compared to asynchronous designs. In some cases, an asynchronous implementation with slow sampling will perform as well as a fast, synchronized design. The goal of this research was to develop methods to design and evaluate asynchronous control systems operating at minimal sample rates. The multirate asynchronous design and analysis methods developed in this report use a time-domain approach based on the closed-loop state transition matrix. Design and analysis algorithms (implemented in PC-MATLAB) are included in an Appendix. The analysis is based on a sufficient stability criterion which gives an objective measure of long-term stability and indicates short-term stability.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1988
- Accession Number
- ADA196911
Entities
People
- Vernon S. Ritchey
Organizations
- Air Force Institute of Technology