We initially tested the Ultrasonic sensor and the Passive InfraRed sensor paired with an arduino and an NAU desktop computer but received inaccurate and unreliable results, leading us to the conclusion that the sensors would not be a good fit for our project.
We tested the KY038 sound sensor using an oscilloscope and sound clips. The potentiometer on the board was adjusted so that the LED would light up when a sound was received. The sound clips did not generate a reading nor did talking but brushing the microphone of the board with a finger and snapping fingers did generate a reading. Because we did not receive expected results and deemed the sound sensor not sensitive enough for the purpose of our project.
We tested the MAX9814 Microphone Amplifier with a bandpass filter and an Arduino Uno. The bandpass filter required a negative voltage which the Arduino did not provide so in order to test the full circuit for functionality two batteries in series with a common ground generated the negative voltage supply needed to have the op amp within the filter working. We received the results we had aimed for, with voltage readings above a one for the frequencies within our filter range.