Implementation of a Localisation Algorithm for Resistance Mapping (Praktikumsbericht)

Abstract

Although thermal protection systems (TPS) are engineered to be resilient, it is beneficial to integrate a health monitoring system (HMS) to determine damages and defects that may occur during a spacecraft's mission. For a greater guarantee of safety, it is important to define these damages as quickly as possible, even in real time, to give the spacecraft and crew the greatest chance to react to an issue. This report defines the algorithm that has been developed to work in conjunction with the HMS proposed by the German Aerospace Center (DLR). This HMS defines the change in electrical resistance across a sample as a result of the presence of a defect. The algorithm uses the change in resistance values to define the location of the defect on the sample. The algorithm used in this report is modified from Liang Barsky method which is commonly used in computer graphics and software engineering. The modified version of this algorithm defines where the resistance is greatest across the sample. The algorithm has been tested with different size samples, and with samples that have missing connections which distribute the current. The algorithm also has been tested using experimental data as well as simulated data. Optimisation and integration of this data with the HMS developed by DLR allowed for defects location to be found even when they account for an area as low as 0.07% of the total sample size.