STUDY, DESIGN AND COMPONENT TESTING OF AN ADVANCED SCAN MECHANISM INCLUDING POWER AND DATA TRANSMISSION FOR A MICROWAVE RADIOMETER

摘要

The study presented is of generic nature covering all possible types of scanner applications such as Large Conical, Cross-Track and Millimetre Wave Radiometers. It included a component and technology survey on which one of the main objectives was to identify new technologies suitable for the use on future scanner mechanisms. Moreover, the requirements for all different types of scanners were identified and a possible design solution of a large conical scanner typically suitable for the use on the Global Precipitation Measurement Mission (GPM) is outlined. New technologies comprising power transfer via ball bearings (fitted with lightweight, ball-riding composite cages), and capacitive signal transfer devices were more closely investigated and breadboard tested in vacuum. Furthermore the paper presents a mechanism that allows slip ring brushes to be lifted from, and re-engaged with the slip ring tracks. This so-called smart slip ring provides 'true' redundancy as the redundant brushes are not in contact with the tracks and are therefore not prone to wear during regular operation. The function of the smart slip ring was tested under vacuum as well.