Application of a multidomain diagnostic expert system in a controlled ecological life support system

摘要

Abstract: A controlled ecological life support system (CELSS) isa critical technology for the Space ExplorationInitiative. To reduce required manpower and increaseCELSS reliability, an automated control system is beingdeveloped for CELSS. One part of the control systembeing investigated is the use of an expert system totroubleshoot mechanical failures in the biomassproduction chamber (BPC) within a CELSS at KennedySpace Center, Florida. An expert system such as thiswould provide mission crew members with instructionsand advice on how to minimize the impact of mechanicalfailures on the crop(s) being raised in the BPC. Thenutrient delivery system (NDS) is one of the mostcritical subsystems of the BPC and is representative ofthe other BPC subsystems. The NDS is the primary focusof the expert system that was developed. The biomassproduction chamber operations assistant fact base wasdeveloped using several experts from the fields ofmechanical engineering and biology. This combination ofexpertise provides the BPC Operations Assistant with aknowledge base that can assess the criticality of amechanical failure, identify the short and long termeffects on the resident crop(s), and provideinstructions for bringing failed mechanical sub-systemsback on-line. The BPC Operations Assistant can alsohelp in the decision process of a failure scenario asto when it might be more cost effective to replant acrop versus continuing growing, or immediate harvestingof the crop(s). The experience gained from the researchand development of the BPC Operations Assistantprovides key insights into knowledge-based monitoringand diagnostic systems that will be required for themanned exploration of space in the future. !2