Research Projects

The strap down Inertial Navigation System (INS) for launch vehicle missions is a real time embedded system that acquires data from motion sensors and rotation sensors and calculates the position, velocity and orientation of the launch vehicle without using external references. For man rated mission, the INS is a safety critical system that plays a crucial role in the success of the mission during the ascent phase of the launch vehicle. The required failure detection and error handling is managed by increasing the redundancy in the system. The INS states shall be computed in quadruple redundancy by the quad processor electronics resident in the system. The states are generated using data from independent sensor channels after proper redundancy management by failure detection and isolation (FDI) logics. Traditionally, a detailed Failure Modes and Criticality Effects Analysis (FMECA) is carried out on the system and, FDI is designed to detect and isolate all possible failure modes. However, validation of the FDI logic is done based on simulated sensor failures, which may not capture all the worst-case combinations on sensor failures and other error conditions. In order to ensure the system design will cater to its safety critical requirements under all conditions, there is a need to impose formal methods for software design and testing. The project aims to apply formal methods for software safety analysis of the failure detection and voting logic of navigation software for man -rated mission to ensure the correctness of the logic in the initial phase of the design.

The project being undertaken by ISRO in collaboration with academia is directly or indirectly beneficial to the society.