Compact and lightweight 3D printed platform for testing attitude determination and control system of small satellites

Abstract

Ground tests of the attitude control system of small satellites can be performed with a test stand that simulates torque free rotations. It consists of a floating platform mounted on a spherical frictionless air bearing joint and equipped with a balancing system that removes the gravity torque acting upon the system. An important design requirement of such platforms is its reduced weight and inertia. In this work we propose an original lightweight 3D printed floating platform made of polylactide (PLA). The utilization of plastic for structural elements is a novelty for this kind of devices, but it also introduces some challenging aspects. Indeed, the reduced stiffness of PLA, when compared with aluminum commonly used in these applications, negatively affects the balancing process. Nonetheless, thanks to the peculiar design we adopted, the platform shows high performance in terms of structural rigidity and balancing accuracy. Experiments evidence that the platform is able to reduce gravity torques to a few tens of micro-Newton meters and a residual offset between the center of mass and center of rotation of about 10 micro meters. These values agree with those of solutions presented in the literature.