Autocommander - A Supervisory Controller for Integrated Guidance and Control for the 2nd Generation Reusable Launch Vehicle

J. E. Fisher, D. A. Lawrence I and J. J. ZhuAvionics Engineering CenterSchool of Electrical Engineering and Computer ScienceOhio UniversityAthens, OH 45701 -2971An Extended Abstract Submitted to the 2002 AIAA GNC ConferenceJanuary 2002ABSTRACTThis paper presents a hierarchical architecture for integrated guidance and controlthat achieves risk and cost reduction for NASA's 2"dgeneration reusable launchvehicle (RLV). Guidance, attitude control, and control allocation subsystemsthat heretofore operated independently will now work cooperatively under thecoordination of a top-level autocommander. In addition to delivering improvedperformance from a flight mechanics perspective, the autocommander is intendedto provide an autonomous supervisory control capability for traditional missionmanagement under nominal conditions, G&C reconfiguration in response toeffector saturation, and abort mode decision-making upon vehicle malfunction.This high-level functionality is to be implemented through the development of arelational database that is populated with the broad range of vehicle and missionspecific data and translated into a discrete event system model for analysis,simulation, and onboard implementation• A Stateflow Autocoder software toolthat translates the database into the Stateflow component of a Matlab/Simulinksimulation is also presented.lCorresponding author, e-mail:dal(_b,ohio.edu, Tel. 740-593-1578,Fax. 740-593-0007