Software Design for Automated Assembly of Truss Structures

Abstract

Concern over limited extravehicular and intravehicular activitiy time has increased the interest in performing in-space assembly and construction operations with automated robotic systems. A technique being considered at Langley Research Center is a supervised-autonomy approach, which can be monitored by an Earth-based supervisor that intervenes only when the automated system encounters a problem. A test-bed to support evaluation of the hardware and software requirements for supervised-autonomy assembly methods has been developed. This report describes the design of the software system necessary to support the assembly process. The system is implemented and successfully assembles and disassembles a planar tetrahedral truss structure. The software is hierarchical and supports both automated assembly operations and supervisor error-recovery procedures, including the capability to pause and reverse any operation. The software design serves as a model for the development of software for more sophisticated automated systems and as a test-bed for evaluation of new concepts and hardware components.