Design, Development and Verification of an Imaging System for PocketQube Satellites

This thesis details the design, development, and verification of an imaging system for the TWIN-SAT satellite mission, currently being developed at TU-Delft. The mission incorporates two 3P PocketQube platforms in a connected configuration, with the imaging system tasked with capturing a sequence of images documenting their separation, serving both engineering analysis and outreach objectives. The project encompasses the entire system lifecycle—from conceptualization and design to development and verification. It builds upon lessons learned from previous missions, aiming to enhance acquisition and data handling capabilities within the limitations imposed by the PocketQube format. The initial phase involved a comprehensive analysis of the spacecrafts' separation dynamics, optimizing the imaging system's performance. This phase led to the selection of an appropriate COTS CMOS sensor and optics. Focus was placed on designing a payload data handling system capable of managing high image data throughput, ensuring continuous image acquisition, and facilitating real-time control and capture. The design and development process involves every aspect of the system including electronics and on-board firmware of the payload data handling system. A custom-developed board incorporates an ARM Cortex-M4 based MCU, a parallel CMOS sensor interface, a high-capacity and throughput SLC NAND memory subsystem, and interfaces for the satellite bus. The onboard firmware includes bare-metal drivers tailored for the payload hardware, the RTEMS real-time operating system, and application software. The drivers, along with a bootloader engineered for the custom board, facilitated the creation of a Board Support Package. This support package enables the use of the RTEMS RTOS with the STM32L4+ microcontroller family, which was previously unsupported. The thesis activities resulted in the production of a functioning Development Model that underwent a verification process to assess its performance and compliance with mission-derived system requirements. The process yielded positive outcomes, guaranteeing the achievement of mission objectives and facilitating the progression towards the development of a ProtoFlight Model.