MS Thesis R. Hager - Hawaii National Marine Renewable Energy ...

5.8 Experimental DiscussionAs mentioned, data have not been collected for the most recent experiment set-up. Againthe hope is this chapter will act as a reference for future students in this field.5.8.1 Experimental ConsiderationsOriginally, an Omega LCCA-25 S-Beam load cell was used. A function generator supplied 15V to the load cell, which had a rated output of 3 mV/V. For a typical excitation force of 0.2lbs. the signal output was: 3mV0.2 1V25 15V 0. 36mVThe NI 9212 DAQ was originally used, which has a minimum voltage range accuracy of0.157 mV, and thus was unable to read the signal accurately. Additionally an S-beam load cellwas a poor choice for this set-up because it introduced bending moments. This set-upshould not be repeated by future students.In constructing the bodies, the following was considered: waterproofing, corrosionresistance, weight, flexing resistance, and flexibility in creating curved shapes. Materialsconsidered were Plexiglas, aluminum, Fiberglas cloth hardened with rosin applied to aStyrofoam or wood frame, and a foam sealant poured into a wooden frame. Ultimately,Plexiglas was the most suitable material.106