Attitude Determination and Control System (ADCS) Testbeds for CubeSats: A Review

The Attitude Determination and Control Subsystem (ADCS) is one of the critical subsystems of CubeSat missions that ensure accurate orientation and stability. Failures in an ADCS can lead to partial or complete mission failure; therefore, experimental validation at subsystem and system levels is essential. However, evaluating ADCS components, sensors, actuators, algorithms, and control designs under realistic conditions remains a challenge. Ground-based testbeds replicate elements of the space environment, using air bearings to provide frictionless motion, magnetic field generators (e.g., Helmholtz cages, Merritt coils, Tetracoil, and Lee-Whiting coils) to reproduce orbital magnetic conditions, and horizon, star, or sun simulators to mimic navigation environments. This paper reviews recent advances in CubeSat ADCS testbeds and highlights simulation methods and hardware platforms. Compared with prior surveys, this review offers a structured and mission-oriented comparative analysis of CubeSat ADCS testbed architectures, systematically evaluating magnetic, air-bearing, optical, and SIL/HIL approaches in terms of fidelity, complexity, and practical applicability. Key findings suggest that integrating Helmholtz or Merritt coils with air-bearing systems is often well-suited for multi-axis dynamic and magnetic validation. In contrast, magnetic-only or optical-focused setups may be preferable for low-cost, single-axis, or sensor-specific testing. Hardware-in-the-Loop (HIL) simulations further enhance sensor and actuator verification. This review highlights the best practices, identifies gaps in current methodologies, and outlines directions for future research, including real-time simulations and AI-enabled testbeds, to support the development of more reliable CubeSat ADCS systems.