Development and testing of a pneumatic circuit to control a 12-Unit CubeSat simulator

Low friction modules are used in aerospace systems laboratories for simulating microgravity conditions giving us the opportunity to test space instrumentation on the ground. This thesis was chosen because the sizing of high pressure pneumatic systems is in generally critical because there are many attributes that must be considered in order to better estimate the pressures needed. Furthermore, the pneumatic system uses Air-bearings, which is an innovative technology to minimize the friction between two surfaces using a nanolayer of air. That said, this thesis presents the development and testing of a pneumatic circuit and its control electronics on board of a CubeSat microgravity simulator formed by 12 cubic units. The pneumatic circuit has two main purposes: the first one is that it has to keep lift up on a glass table the entire simulator with three air bearings, the second one is to control the planar motion with sixteen propulsion nozzles. All study is based on a main requirement that is use only dry air (at 10 bar maximum) for all pneumatic circuit and no others gasses like the CO2 for example. All fluid load losses along the circuit are studied in the thesis starting from requirements of module acceleration, for the side of propulsion nozzles, and requirements of lift up for the side regarding the air bearings used for reducing the friction with the table. For the study of the sizing problem of the compressed air tank, which is the largest component of all system, requirements in terms of total floating time have been used. A Simulink model has also been developed to precisely define the working pressure of the pneumatic circuit and also to better estimate all localized and distributed load losses. The thesis concludes by documenting all the tests conducted on the operating module. The report specifically covers the results of linear and torsional acceleration tests, along with tests performed to determine the module's total floating time with all thrusters off. In these tests, the thrusts and the torques values for various combinations of Frequency, Duty-Cycle and Impulse duration of PWM control signal are obtained. The purpose of these tests is to verify the correct sizing of all the components in compliance with all the assigned project requirements.