Miniaturized Time Domain Terahertz Non Destructive Evaluation for In-Orbit Inspection of Inflatable Habitats and Thermal Protection Systems

Picometrix's time-domain terahertz (TD-THz) non-destructive evaluation (NDE) technology could be used to inspect space flight structures such as inflatable space habitats, thermal protection systems (TUFI-type tiles, SOFI TPS), for voids, disbonds, and damage such as tearing and micron-meteorite impact. The current instrumentation paradigm is that a multi-purpose TD-THz control unit is used to provide common drive, data acquisition, and analysis functionality to interchangeable sensors and imaging which connect to the control unit with a fiber-optic/electrical umbilical. However, the current COTS control unit is substantially larger and heavier than would be desirable for a space-flight capable unit. In Phase II we will construct a prototype compact TD-THz control unit with a fiber optically coupled remote compact TD-THz reflection tomography sensor based on the Phase I designs. At the end of a successful Phase II, and transitioned into Phase III, we envision that a hand-held A or B-Scan NDE imager could attach to a control unit, sufficiently robust for spaceflight, no larger than a shoebox. In Phase II, it should be possible to reduce the size of the control unit to approximately 1/3 of the current values to, for example, 14 in. X 10 in. X 4 in. and 15 pounds.