As we prepare for the on-site PDR presentation, which Northrop Grumman confirmed for Monday (10/24), we are continuing to test and collect data for possible detection methods. Methods we focused on this week were Eddy currents and capacitance. A paint thickness gauge, which is highly used in the automotive industry to measure the thickness of the paint of the outer body, was used to measure eddy currents to calculate the thickness on our test samples. From the experiment, we were able to see a noticeable difference between the thickness of the non-defect section to the defect section on both unidirectional and woven carbon fiber prepreg.

To improve our capacitance measurement method that we have been testing for the past few weeks, we refined the circuit to include a Colpitts oscillator in addition to the RC oscillator. By incorporating a Colpitts oscillator, we are able to generate our own signal.