Laboratory Setup

The first immage shows the laboratory experimental setup of a simple prototype structural health monitoring (SHM) systems of a thermal protection system (TPS) component. The SHM system consists of four sensors, a CPU/GUI, a signal generator, an amplifier, and a junction box.

CPU

The CPU and data storage system are housed inside a portable case and assembled by National Instruments. The graphical user interface (GUI) was programmed in Labview.

Function Generator

The function generator produces the excitation signal required by the active SHM system. The excitation consists of a sine sweep from 0-1500Hz over a period of 2.0 seconds. The peak-to-peak amplitude is 1.5 volts.

Amplifier

The amplifier takes the excitation signal and amplifies it by a factor of 100. It sends this signal straight to the piezoelectric actuator attached on the TPS plate.

Junction Box

The junction box gathers signals as input to the CPU. It takes the excitation signal straight from the signal generator. The amplified signal would be too powerful for the junction box. The junction box also gathers the response signals from the three monitoring sensors attached to the TPS plate. All four signals are are sampled at 10kHz and stored for further processing.

Procedure Video

This video shows the procedure usesd for data collection of one "round" of signals. Windows Media Player is required to play this clip. Please be patient while video downloads. This may take up to several minutes.