| Testing performed in the reverberation chambers at the University of Alberta's Mechanical Engineering Acoustics and Noise Unit (M.E.A.N.U.) is sensitive to variations in the air temperature and relative humidity. The errors that these variations induce in the test results are compounded by the practise of entering the chambers periodically to reposition the microphone.;As a result, the implementation of an automated microphone positioning system was undertaken. The objective of this thesis project was to evaluate previous design work, complete the design to the implementation stage, and evaluate the performance of the manipulator.;The configuration selected was a spherical geometry manipulator, consisting of a telescopic boom capable of rotation through two orthogonal axes. Suspended from the ceiling, the manipulator's range of motion is such that the microphone can be positioned to 90% of the legal testing positions based on A.S.T.M., I.S.O., and A.N.S.I. standards, with an accuracy of ;The main performance objective was that the manipulator be capable of moving to any position in the chamber in under thirty seconds. As installed, the positioning time is limited by the performance of the telescopic boom, which requires just under a minute to move through its in range of motion. Also, depending on the position selected, the azimuth rotation of the manipulator may require a full minute for its range of motion. Although alterations could be made to these axes, the performance of the manipulator is acceptable for its intended purpose. |
