Reliability and Quality Assurance Programme for Space Missions - Indian Scenario
TNARASIPUR SIVARAMASASTRY, NANJUNDASWAMY; KRISHNAN, RAJANGAM
ISRO SATELLITE CENTRE
The Indian Space Program since its inception has passed through three important phases, viz. experimental phase, developmental phase and operational phase. The reliability and quality assurance system also has followed an evolutionary process to meet the requirements of the corresponding phases. The initial phase the R&QA program mainly focused on testing of finished hardwares of spacecraft subsystems and systems for verification of compliance to performance specifications. With experience, it was realized that this methodology was not adequate to realize reliable systems meeting the project goals and time schedules as well. The malfunctioning / failures encountered during subsystem/system testing posed several difficult situations involving major changes in design and fabrication processes resulting in time over runs and excess resource deployments. In the subsequent phase, the approach was improvised by introducing effective review systems to review the design and fabrication processes. As the systems grew, the concepts of quality assurance got enhanced by critical review of selection and application of parts, materials and processes. The test and evaluation methodology was also broadened to comprehensively simulate the total environment the spacecraft would encounter, enveloping the ground and space environments like thermal vacuum, humidity, vibro acoustics, electromagnetics and radiation during the performance evaluation of the system prior to launch. These additional steps indeed increased the confidence in assuring the system performance. The third phase viz. operational phase was the key phase reflecting the maturity of quality system of Indian Space Program. During this important phase the ISRO programs mainly in satellite communication and remote sensing were geared up to provide uninterrupted services in TV broadcasting, telecommunications, data communications and weather forecasting, remote sensing applications and recently telemedicine and tele-education. Analytical tools of reliability engineering and failure analysis have played significant role during operational phases. Configuration control, non-conformance management, comprehensive data base of on orbit observations and anomalies, failure analysis and institution of self correcting mechanisms are some of the important improvisations in the R&QA methodology introduced during this phase. With the rapid increase of user demands, the number of spacecraft to be realized grew significantly. To meet this requirement, it became necessary to seek participation of Indian industries in the satellite building activities. Vendor development, training, qualification and certification have been comprehensively planned and implemented successfully. Recently, ISRO has made an entry into the global space market to build subsystems, systems and satellites as well as to provide spacecraft operational services for international customers. These customers have put forth several stringent demands on product assurance discipline. This has necessitated fine tuning of R&QA approach and methodology to meet the competitive global market demands. This paper attempts to share the experience of ISRO in the Reliability and Quality Assurance of Spacecraft Projects during the past three decades and the lessons learnt during this process.