A Fuzzy Expert System Architecture Implementing Onboard Planning and Scheduling for Autonomous Small Satellite

A crucial element in achieving small satellite fully autonomy is onboard automated planning and scheduling. Though lots of successful applications about it in spacecraft operations have recently been reported, and all of them are important for the development of this field, the inherent fuzziness and uncertainty of planning and scheduling was ignored made the achieving of onboard automated planning and scheduling system become idealization and no reality. In response to above-mentioned requirement, this paper presents an architecture which is developed using rules-based Fuzzy Expert System (FES). Fuzzy expert systems not only maintains the value of based rules and the merit of using fuzzy logic control to describe uncertainty systems, and utilizes the predominance of using expert systems to denote and control knowledge. In order to adapt the requirement of onboard operation, the resource restrain is considered in the architecture, such as processing speed of CPU, the capacity of storage and the real-time requirement. As the application of this architecture, this paper also describes an onboard automated planning and scheduling system in the SMMS, which is a small satellite of Research Institute of Satellite Engineering and Technology of Harbin Institute of Technology and will be launched in 2000.