NASA 1996 SBIR Phase I


PROPOSAL NUMBER : 96-1 14.02-3155

PROJECT TITLE : H-infinity Robust Adaptive Controller for Reusable Launch Vehicle

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

Reusable launch vehicles (RLVs) require superior robustness and adaptability to mitigate the effect of unmodeled structural modes and uncertain system parameters on the performance of the attitude control system. The design specifications of spacecraft attitude control systems are usually quantitative instead of qualitative, and the spacecraft model is only an approximation of the true system. Existing adaptive control schemes are deficient because they can only deal with qualitative specifications and small amount of nonparametric uncertainties. We propose to use a new adaptive control scheme, H-infinity Robust Adaptive Control (HIRAC), developed by the proposed Principal Investigator, for the attitude control of RLVs. This control scheme can guarantee quantitative robustness levels, and it has the ability to handle large parametric and non-parametric uncertainties. It achieves these improvements over the prior art using an innovative self-tuning capability. Furthermore, the HIRAC has a systematic non-iterative design procedure, so the design process is much easier and more reliable than other adaptive control design schemes. The assumptions required for the HIRAC are very general, allowing this technology to be easily applied to commercial applications, such as automobile active or semi-active suspension control system, cruise control system, HVAC, etc.
POTENTIAL COMMERCIAL APPLICATIONS
The proposed H-infinity robust adaptive controller can be applied to industrial systems such as aircraft, spacecraft, automobiles, ships, and robotics. The marketability of this product is high due to the vital importance of this technology to both commercial industries and government applications.
NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR
Dr. Chujen Lin
Intelligent Automation, Inc.
2 Research Place, Suite 202
Rockville, MD 20850
NAME AND ADDRESS OF OFFEROR
Intelligent Automation, Inc.
2 Research Place, Suite 202
Rockville, MD 20850