• Acoustical test chamber

      Cabuk, Cansu (2018-05)
      The purpose of this project is to create an acoustical test chamber for use by students and faculty of the Division of Engineering Programs at SUNY New Paltz. An acoustical test chamber is a controlled environment that is instrumented with a microphone array. This allows the user to perform accurate acoustical measurements on sound sources without outside interference while also dampening internal sound. These measurements will help the user determine vital sound parameters and display information relating to the sound signal. The properties of sound that are measured include sound intensity and sound frequency. Sound frequency information is plotted and displayed using a spectrogram. In addition, a sound localization feature using time difference of arrival estimation was implemented into the chamber’s functionality. The sound is measured using four electret microphones, then transferred to a computer utilizing stereo microphone inputs. The computing environment, MATLAB, and its functions were utilized by establishing a user friendly, interactive interface between the sensor hardware and the test environment. MATLAB’s functions and Graphical User Interface (GUI) feature, proved to be critical tools in simplifying the data acquisition, algorithmic and display processes. Before final construction, the sound location feature produced results with an average of 17% error. While after final construction, the number of trials that produced feasible results decreased drastically. This may be down to slight changes in the array geometry during the chamber’s construction process. This project is important as it provides engineering students at SUNY New Paltz, an opportunity to further enhance their exposure to acoustical testing techniques. The sound chamber will be used to verify analysis techniques learned in the classroom, in addition to providing research opportunities to students. However, the sound location feature is inadequate and still needs development.