Description: The U.S. hypersonic ground- and flight-test communities require robust structural sensors that operate in relevant hypersonic environments. The focus of this project is the development of vehicle structural health monitoring (SHM) systems for use with hypersonic vehicles in extreme environments (e.g., high thermal, vibrational, and acoustic environments). For hypersonic vehicles in order to deploy SHM systems through a wide range of environmental conditions experienced by the vehicle, it is crucial to develop hardware that can function at those temperatures in addition to robust structural monitoring algorithms. The key to this is the development of sensor systems that can survive the harsh usage conditions and the extreme working environments. This program will develop Bismuth Scandium Lead Titanate based SHM systems for Hypersonic Vehicles. The goal will be to develop SHM systems that will include 3 major components a. High-temperature sensors: a flexible sensor layer with BSPT sensors fabricated for use in hypersonic vehicle nonablative areas facing temperatures approx. 600 C . A novel manufacturing process will be developed during the SBIR to enable the production and packaging of the sensors along with methods for their installation in the high temperature areas. b. Data-Acquisition (DAQ): a passive-active electronic module that interfaces with the BSPT sensors will be developed that will use ultrasound induced transducers combined with low to high frequency data collectors. c. SHM Software: advanced algorithms to detect, characterize, and track damage (including impacts, cracks, disbonds, etc.) along with an easy-to-use graphical user interface (GUI). Physics-informed diagnostic software will be developed to use Artificial Intelligence (AI) and Machine Learning (ML) using the data from the sensors to detect damage under extreme environment and to characterize environmental conditions through ML techniques.

Benefits: The proposed hypersonic SHM system can be used for any NASA platforms including near-term ground- and flight-test opportunities in addition to bringing NASA closer to the goal of "aircraft-like" operations for reusable hypersonic vehicles. The resulting sensor technologies and data methodologies will increase efficacy of data on near-term flight tests. Furthermore, the technology could bring NASA one step closer to the goal of an effective neural network of sensors, despite harsh environments, that will improve safety and advance flight resource utility. The integrated system will provide useful information regarding structural integrity of the hypersonic structures. The system will also fill gaps that preclude the effective use of large-area distributed sensors in extreme high-speed environments to understand the condition of a hypersonic vehicle and predict the remaining life and capabilities of the vehicle structures. In addition with the expected development of reusable hypersonic vehicles, data from the sensors will fulfil a critical need for advanced methodologies that synthesize data from a range of extreme environment sensors into integrated vehicle health management (IVHM) systems that will support vehicle flight exposure, component maintenance requirements, and life estimates. The proposed SHM system can be used for any types of high temperature structural monitoring in applications such as Refineries and ground testing.