Developing a signal processing tool for rocket motor measurements

Abstract

Solid rocket propellants have various applications, including weapons, satellites, and air bag technology. In these applications burn rate and pattern prediction are important parameters in predicting ballistic motor performances and motor design. While existing equations accurately predict burn rates for most solid engine propellants, these standard equations do not adequately capture rates associated with certain engine formations, such as Solid Fuel Ramjets (SFRJ) and some Solid Rocket Motors (SRM). The propellant burning rates in SFRJ and SRM are not homogeneous due to several factors, such as the flowfield, edge effects, etc. To overcome this deficiency, Atlantic Research Corporation (ARC) is developing a novel ultrasound technology to measure burn rate directly. Technical challenges arise, however, when the echo of the propellant surface is weak and difficult to detect, because of limited ultrasonic power, the mismatch of case and propellant impedance, and associated electronic and magnetic noises. Thus, the main objective of this project is to accurately recognize the echo of sound waves from time-series data corrupted by noise. The design, testing, and implementation of an algorithm to extract burn rate profiles from ultrasound measurements is discussed. Also described is the design of a prototype human-computer interface that is used to record and display burn rate data.