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1	Design, Manufacturing, and Testing of a Cold Gas Thruster System With Minimized Actuators Jones, Cameron Paul 01 December 2024 (has links) (PDF) Cold gas thrusters are commonly used on spacecraft for in-space attitude control and adjustment. These thrusters use inert gases stored at high pressures to create small amounts of thrust and typically have multiple fixed outlets, each controlled by its own actuated valve, to control the direction the thrust is directed. Having individual outlets with their own actuated valve leads to a great amount of power drawn for the individual actuators, as well as general added complexity by having a large number of parts. To address this issue, this thesis investigates an attempt to minimize the number of actuators required for a cold gas thruster system to operate. This thesis details the design, analysis, electronics integration, manufacturing, and testing of a cold gas thruster system with as few actuators as possible. In addition, a thrust target, a maximum response time, and a long duration test regime were set as requirements to drive the design. From these goals and requirements, a cold gas thruster system that uses a single central selector valve to control the actuation of four outlets while only using two motors was designed. The selector valve design uses a sleeve that rotates and moves vertically to align ports in the valve to allow the propellant gas to flow freely through the valve and to the nozzle where thrust is produced. The sleeve is rotated by a motor connected to a pair of gears, and the vertical motion is controlled by a motor with a lead screw. Along with the mechanical design of the system, a great amount of compressible flow fluids analysis was performed. This analysis was used to determine the geometry of the outlet nozzle and its tolerances. In addition, a model was created using MATLAB and Simulink to predict the pressure drops throughout the system. This model is used to estimate the necessary pressure regulator outlet pressure that produces the nominal thrust. The electronic control panel was developed to control the motors as well as to obtain performance data. Stepper motors were used to control the selector valve and controlled by a Teensy microcontroller board and custom libraries to operate the stepper motors simultaneously. Pressure and thrust data were collected from sensors that report the data to an Arduino microcontroller. The testing performed was highly successful with the thrust requirement and the long duration test regime requirements were achieved, while the maximum response time requirement was missed, but not by a large margin. The targeted thrust was able to be produced, and the required endurance test profile was successfully performed. The response time requirement was met for two out of the three valve actuation motions and was slightly exceeded for the last one. Cold Gas Thruster Propulsion Mechanical Design Propulsion and Power
2	The I2T5 : Enhancement of the Thermal Design of an Iodine Cold Gas Thruster Pereira, Roger Michael January 2020 (has links) The I2T5, an iodine-propelled, cold gas thruster, developed by ThrustMe, France, is the first of its kind to make it successfully to space. Due to its simple, reliable and cost-effective design, it is a suitable propulsion system for CubeSat missions with low delta-V (ΔV) requirements. To ensure that the I2T5 performs at its peak, it is crucial to maintain good thermal control of the thruster, to keep it within the operational temperature range. The first flight measurements of the I2T5 provided insight into its thermal performance. It was observed that the required temperature to sublimate the iodine propellant was not reached within the expected time frame, which led to a longer warm-up period, and a reduction in thrust. The problem arose due to an unforeseen conductive thermal contact between the tank and the thruster walls. This thesis delves deeper into this issue, and focuses on alleviating the total conductive heat loss from the tank to the satellite frame, where the I2T5 is integrated. The insulating washer-bolt configuration of the I2T5 side panels is observed to be responsible for the conductive heat transfer. A preliminary analysis is performed to obtain an initial maximum for the conductive heat flux lost to the satellite frame. A plan of action is then determined to optimise the geometry, material or configuration of the insulating washers to lower the maximum heat flux value. Following this, an experiment was conducted with a new washer-bolt configuration to determine the heat flux values. A case study is performed for the orbital environment heat fluxes that the I2T5 would receive if it were integrated to a CubeSat in sun-synchronous orbit. An overview of results shows that, for the thermal simulations, all the methods employed to reduce the conductive heat loss at the frame were effective. The experiment provided neutral results, and would need to be repeated with different experimental parameters to have a clear perspective of the heat losses. In reality, the satellite frame receives radiative fluxes in addition to conductive heat fluxes, but radiation is not considered for this thesis, and is suggested as a prospective study. Cold gas thruster I2T5 CubeSat propulsion thermal analysis heat transfer thermal resistance orbital heat fluxes Aerospace Engineering Rymd- och flygteknik
3	Propulsion System Development for the CanX-4 and CanX-5 Dual Nanosatellite Formation Flying Mission Risi, Benjamin 04 July 2014 (has links) The Canadian Nanosatellite Advanced Propulsion System is a liquefied cold-gas thruster system that provides propulsive capabilities to CanX-4/-5, the Canadian Advanced Nanospace eXperiment 4 and 5. With a launch date of early 2014, CanX-4/-5's primary mission objective is to demonstrate precise autonomous formation flight of nanosatellites in low Earth orbit. The high-level CanX-4/-5 mission and system architecture is described. The final design and assembly of the propulsion system is presented along with the lessons learned. A high-level test plan provides a roadmap of the testing required to qualify the propulsion system for flight. The setup and execution of these tests, as well as the analyses of the results found therein, are discussed in detail. aerospace microsatellite nanosatellite propulsion formation flying canx4 canx5 canx-4 canx-5 canx-4/-5 SFL UTIAS cold-gas thruster satellite CNAPS NANOPS nano sulfur hexafluoride SF6 vibration testing spacecraft environmental testing propulsion testing low earth orbit canx2 canx-2 station keeping orbit maneuver orbital station-keeping liquefied cold-gas propulsion micropropulsion engineering space canadian space flight laboratory canadian advanced nanospace experiment PSLV micro-propulsion thruster interferometry ground moving target indicator on-orbit servicing and inspection 0538

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