The Evolution of a Test Process for Spacecraft Software

The Johns Hopkins University Applied Physics Laboratory formed an embedded software group in 2001. In addition to defining the process for developing and testing flight software, the group had to quickly apply those new processes to a series of four different spacecraft missions from 2001 through the present. The paper describes the evolution of the software testing approach for embedded flight software during this time. After a brief description of the four spacecraft missions, this paper presents our initial approach to testing and how that approach changed with each mission, as our resources were overextended and our schedules were compressed. The final section of the paper presents the changes that we believe had the most significant impact on our testing efforts and our proposed test approach for the next mission.