Development of a Cold Gas Propulsion System for the ... - SSL - MIT

5 Single-Stream Component Testing
An incremental program of testing for the TALARIS CGSE was designed with three major steps. First, the
individual components of the system, which had been selected based on the results of the MATLAB
model as well as other considerations, would be tested to verify that their performance met the
requirements of the CGSE. Next, a full eight-thruster system would be constructed, and the verification
tests would be repeated. The main purpose of this step would be to ensure that components which met
requirements on their own would continue to do so even when they had to interact with a greater
number of components in a complex system. For instance, the regulator would have to be capable of
maintaining pressure on the low side of the CGSE with higher mass flows resulting from multiple
thrusters firing at once. Finally, the eight-thruster system would be fully integrated with the rest of the
TALARIS hopper and tested under actual flight conditions. In this phase, the idea was to move from
verification to validation. It would be necessary to ensure that the CGSE interacted effectively with the
other subsystems of the TALARIS hopper in order to produce the desired result: a controllable vehicle
capable of completing a demonstration hop. To achieve this goal, it would be necessary to have not only
properly functional hardware and software, but also skilled and practiced vehicle operators. Thus,
additional goals throughout these three phases of testing were to gain operational experience and to
develop procedures and protocols for optimal operation of the CGSE that also ensured the safety of
every person involved with TALARIS.
For the first step in the three-step plan, a single Omega SV128 solenoid valve was purchased, in order to
verify its suitability before proceeding with the purchase of enough valves to build a full eight-thruster
flight system. A single aluminum nozzle was machined, designed for 425 psia chamber pressure as
described in section 4.3. The Tescom 44-1363-2122-408 regulator was also purchased. Finally, tubing
and fittings were purchased and assembled to connect the components together. Since this setup fed
gas to a single thruster, as opposed to the multiple branching flow paths that would be needed in the
full eight-thruster system, this first round of component tests was also referred to as single-stream
testing.
5.1 Objectives
Several measurable outcomes of the single-stream component tests were defined. The first was to
characterize the thrust output of a single CGSE thruster. The maximum amount of force that the
thruster could produce when fed through the flight regulator would be determined. It was assumed that
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