Command and Data Handling-Driven Spacecraft Operations Using Hardware-in-the-Loop Simulation

Abstract

CubeSats have emerged as a cost-effective platform for space research and technology demonstration, but mission success remains highly dependent on reliable command execution, telemetry handing, and subsystem coordination. Traditional satellite evaluation methods often emphasize isolated subsystem validation or environmental simulation, while providing limited insight into end-to-end spacecraft operations governed by the Command and Data Handling (CandDH) subsystem. The thesis addresses the need this gap by developing and evaluating a COSMOS-based CandDH architecture integrated with the EyasSat educational spacecraft to enable realistic, flight-like command and telemetry operations in a hardware-inthe- loop environment. While attitude determination and control subsystem (ADCS) experiments are used as a representative case study, the primary contribution of this work lies in demonstrating how CandDH-driven command sequencing, mode management, and telemetrytriggered logic can be exercised and validated prior to flight. Experimental results show reliable execution of scripted command sequences, deterministic telemetry-driven responses, and repeatable operational scenarios including payload activation, mode transitions, and closed-loop attitude responses. The integrated EyasSat–COSMOS environment provides a modular and extensible spacecraft operations testbed that shifts validation from isolated subsystem performance toward system-level operational readiness. This approach reduces integration risk, supports operator training, and enables future expansion toward full mission timeline testing involving multiple spacecraft subsystems. The results demonstrate that a low-cost educational spacecraft can effectively support CandDH-centric validation of spacecraft operations, bridging the gap between software-only simulation and flight hardware testing.