Flexible Data Acquisition and Control System for TPX/G557

This paper describes the Data Acquisition and Control (DAC) system developed for the Two Phase eXperiment (TPX). TPX has flown on the US Space Shuttle STS60 as Get Away Special (GAS) G557. The objective of the TPX is to demonstrate the behaviour of a capillary pumped two phase heat transfer system in low-gravity environment. During the flight the DAC system is operating stand-alone, controlling the experiment steps and collecting and storing the experiment results.

A table driven approach for the control software was selected to obtain a configurable and flexible data acquisition system. The flexibility was required to allow for late adaptation of the experiment parameters and sequences within the short time frame of the project.