Development of a thrust balance micro-thrusters

• Grant number: 16/05927-3
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2016
• End date: March 31, 2019
• Field of knowledge: Engineering - Aerospace Engineering - Aerospace Propulsion
• Principal Investigator: Rodrigo Intini Marques
• Grantee: Rodrigo Intini Marques
• Host Institution: Instituto Nacional de Pesquisas Espaciais (INPE). Ministério da Ciência, Tecnologia e Inovação (Brasil). São José dos Campos , SP, Brazil

Abstract

This proposal is for the development and test of a scientific instrument: a thrust balance for pulsed plasma thrusters (PPTs) space electric propulsion devices in the 20-150 micro-Newton, not available in Brazil. The immediate goal is to measure the thrust produced by the double discharge PPTs developed at LCP/INPE. However, this instrument will be able to measure the thrust of other types of thrusters. The thrust balance will be the object of study of an MSc post-graduation student at PCP/ETE/INPE. The thrust balance will use a torsion pendulum configuration due to its relative simplicity, low cost and effectiveness. Sources of perturbation and errors will be evaluated and quantified for the thrust and impulse measurements. The main component of a torsion thrust balance is the arm and its dimensions will be determined so it can have a rectangular tubular shape allowing the PPT and counterweigh to be attached to it while it has an adequate strength and reduced mass. The rotation axis of the thrust balance will be parallel to the gravitational acceleration vector and held in place by special flexible torsion pivots. Knowing the thrust balance arm dimensions, the torsional spring-rate of the pivots and the expected thrust of the PPTs, the maximum linear displacement will be determined (in the order of micro-meters). This displacement will be measured using an optical sensor, particularly non-invasive and intrinsically electromagnetically (EM) immune, since the PPT produce strong EM fields. The thrust balance calibration will be performed with a device we call electrostatic calibration device (DCE) that will be developed together with the thrust balance in this very project. The DCE produces an electrostatic force proportional to an electric potential applied and it can be calibrated with a precision analytic mass scale with traceable calibration. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ANSELMO, M. R.; MARQUES, R. INTINI. Torsional thrust balance for electric propulsion application with electrostatic calibration device. MEASUREMENT SCIENCE & TECHNOLOGY, v. 30, n. 5, MAY 2019. (16/05927-3)

OLIVEIRA SOARES, DIOGO LEON; MARQUES, RODRIGO INTINI. In vacuum dynamic and static tests of a thrust balance for electric propulsion with hysteresis analysis and behaviour prediction with transfer function. MEASUREMENT SCIENCE & TECHNOLOGY, v. 32, n. 12, DEC 2021. (16/05927-3)