NEW AOCS DEVELOPMENT AND VALIDATION APPROACHES

摘要

Recent programmes on both commercial and institutional space markets have remained very challenging from the technical viewpoint and also demand high quality and reliability standards. Simultaneously, new developments have to be conducted under more and more stringent cost and delay conditions. Within this context, MATRA MARCONI SPACE (MMS) has implemented innovative design and validation approaches. Their application to the AOCS is dealt with in this paper. The development of an AOCS requires detailed design studies and related functional validation. The processes supporting these engineering activities have been defined : design of the control laws, AOCS application software specification, functional validation of the coded application and prediction of in-flight performance. The major improvements brought in these processes for the past few years are presented here-after. Regarding AOCS application design, re-use procedures in order to benefit from existing basic building blocks from previous programmes have been defined. The process mapping has also shown that management of data exchanges is a major issue. Methodologies to master data exchanges have been developed. Concerning the AOCS application software specification and validation, an integrated AOCS studies and flight software development approach has been implemented. It allows exhaustive functional validation of the AOCS flight software before the real time tests where the application software is implemented on the target computer. Operational use of innovative development and validation approaches also leads to new organisational schemes : networking and concurrent engineering between AOCS studies, software development and real time tests teams. An incremental scheme is also followed to reduce development duration. In order to assess the benefits provided by these new approaches, and to identify areas where progress can still be made, indicators have been defined and implemented. Some measured achieved gains are presented as a conclusion to this paper.