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This paper presents recent developments in designing a novel 6 degrees of freedom (DOF) experimental testbed for validation of guidance, navigation and control algorithms for nanosatellites. The main catalyst for this research is the desire to experimentally test these algorithms in a 1g laboratory environment, in order to increase system reliability while reducing time-to-launch and development costs. The system stands out among the existing experimental platforms because all degrees of freedom of motion are dynamically reproduced. The majority of the existing platforms guarantee at the most 5 DOF force-free motion, excluding the vertical motion. The sixth DOF, when considered, is reproduced only from a kinematic point of view, by using an electrical motor. The presented testbed achieves 6 DOF dynamical motion by using 12 cold gas thrusters. A condition of almost frictionless motion along the 6 DOF is realized using 3 sets of air bearings: linear air bearings for the planar translational motion of the platform over an epoxy floor, air bearing pulleys embedded in a mass balancing system for the gravity-free vertical motion, and a spherical air bearing providing the additional 3 rotational DOF. The challenges of near gravity-free vertical translation in a 1g field are addressed using a unique counterbalancing system.

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This paper presents a novel six degrees of freedom ground-based experimental testbed, designed for testing new guidance, navigation, and control algorithms for nano-satellites. The development of innovative guidance, navigation and control methodologies is a necessary step in the advance of autonomous spacecraft. The testbed allows for testing these algorithms in a one-g laboratory environment, increasing system reliability while reducing development costs. The system stands out among the existing experimental platforms because all degrees of freedom of motion are dynamically reproduced. The hardware and software components of the testbed are detailed in the paper, as well as the motion tracking system used to perform its navigation. A Lyapunov-based strategy for closed loop control is used in hardware-in-the loop experiments to successfully demonstrate the system's capabilities.