Title: Design and Development of Fault-Tolerant Software for Data Handling Unit of a


   SUPARCO, the space agency of Pakistan in 2014 launched a Student Satellite Program (PNSSP). The proposed program is a way forward for a sustainable and progressive student satellite development under the umbrella of SUPARCO. This program will provide the platform for collaborative efforts in real world space engineering applications for the academia. The PNSSP will consist of a series of satellites, which will be designed & developed with the help of universities. Pakistan National Student Satellite-1(PNSS-1) will be the first of this series. PNSS-1 will have many subsystems including Data Handling Unit, On-Board Computer etc. Data Handling Unit (DHU) is a key component in satellites, in our case the satellite being PNSS-1. It can easily be regarded as the brain of the satellite. It collects telemetry data from all the subsystems and sends it to the ground station through RF communication chain.
    Our job is to design and develop a fault-tolerant software for the Data Handling Unit of PNSS-1.The main problem we had to deal with was to introduce redundancy in our design approach and find a suitable micro-controller that fulfills all the physical (temperature requirements, number of I/Os etc.) and software requirements (FreeRTOS portability). To make the software fault-tolerant we had to take into account both software and hardware levels of faults/failures. Our initial design proposal included all kinds of software redundancy elements e.g. saving data at multiple places. Hardware, which was designed by the other group, had back-ups for every hardware element so to avoid single point failures. We had to come up with a software design to detect if any component is faulty, shift to its back-up autonomously and if back-up’s not available, then work without that component in a reduce state.
    FreeRTOS was decided as the working OS for our microcontroller because of its maturity and open source. Now we have ported FreeRTOS on to our microcontroller and implemented various error-correction and data handling schemes

Advisor:  Dr. Muhammad Tahir   

Group Members:

Name: Khawaja Zaigham Feroz
Phone: 03087226024

Name: Muhammad Asim
Phone: 03217395765

Name: Arslan Khan
Phone: 03444576380