DESIGN AND APPLICATIONS OF ZIGBEE-ENABLED WIRELESS SENSOR SYSTEMS FOR A SPACE RELEVANT ENVIRONMENT

Open Access
Author:
Weir, Erik David
Graduate Program:
Electrical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
November 18, 2010
Committee Members:
  • Sven G Bilen, Thesis Advisor
  • Julio Urbina, Thesis Advisor
Keywords:
  • wireless sensor system
  • zigbee
  • thermal protection system
  • thermocouple
Abstract:
A prototype wireless sensor system is developed to collect data from sensors that are of importance on space platforms, and also important in the testing of these systems in space-relevant environments. The elimination of wires and the associated failures such as chafing, sparking, ageing, and connector issues can increase reliability and design flexibility while reducing costs. These factors present an appealing case for the pursuit of wireless solutions for harsh environments and particularly for their use in space and on spacecraft. Recent testing of this prototype system in the NASA Ames Research Center’s Aerodynamic Heating Facility during Test 289 in January 2010, demonstrated the feasibility of using wireless sensors in ground test programs and point to their use on flight vehicles. The test demonstrated data collection of a type-K thermocouple at ±2.5 °C resolution, with real-time data rates of 1 Hz, and high-speed data collection rates of 60 Hz and higher. The presence of the plasma, heat, and vacuum within the chamber did not inhibit data acquisition, although there was a period of radio blackout while there was plasma between the system and the receiver. A further test was attempted in the Panel Test Facility to show 100% communication uptime and multiple sensor support, and although that test was halted by critical battery failure, an upcoming “wedge” test in the Interaction Heating Facility, will showcase a fully functional system. With continued refinement, the next version of the wireless sensor system has the potential to exhibit an increase in data frequency, a dramatic increase in battery life, and a marked reduction in size. This thesis demonstrates that wireless sensor systems have the capability to replace wired systems in space applications. Future testing will further increase the technology readiness level of the wireless sensor system, verifying that wireless systems have a place on future flight missions.