Method and Simulation of On-Orbit Sub-microthrust Evaluation

<p>With the advent of smaller satellites, along with the need for less than 0.1 μN precision attitude control for interferometry and imaging missions, finer micro- to sub-micro- thrusters have become an area of high interest. As thrusters are developed and ground-tested, it is necessary to evaluate their thrust performance on-orbit. On-orbit measurements offer actual thrust performance in mission conditions, free from ground facility vibrations and miniaturization restraints, and allow a thruster system to achieve a NASA Technology Readiness Level (TRL) of 7-8. A review is conducted of existing and proposed ground and on-orbit thrust measurement techniques. Experimental gaps and complementary methods are examined along with the current thrust resolution limits. A novel fusion technique combining attitude determination, torsional balance, and filtering techniques is proposed to increase resolution beyond current on-orbit minimums, 4μN, via a dedicated sub-μN on-orbit thrust measurement mission. A simulated case study in the application of this measurement technique to a theoretical Casimir-thruster-equipped, 10^-7-10^-13 N, smallsat mission is explored. A detailed error analysis is conducted, and the technique is found to be analytically viable for greater than or equal to 10^-7 N on a 1U nanosat equipped with sun sensor and three-axis gyroscope, as well as physically viable at a TRL 7-9 level. Recommended next steps are modification of the post-processing technique to decrease gyroscope noise and mass restrictions or exploration of suggested alternate methods, including orbit estimation, direct force sensing, and formation flying.</p>

Name thesis:degree_name

MS in Aerospace Engineering

Discipline thesis:degree_discipline

Aerospace Engineering

Year dc:date.available

2022

Author dc:creator

• Hood, Jonathan

Contributors dc:contributor

• Pauline Faure
• Aerospace Engineering
• College of Engineering

• Thrust Measurement
• On-Orbit Measurement
• Propulsion and Power

Identifier

10.15368/theses.2022.56

OAI identifier oai:identifier

oai:digitalcommons.calpoly.edu:theses-4068