Abstract: A sampling arm coupler device comprises a coupler comprising a rectangular tructure or bar, having a cylindrically hollow bore therethrough. The bar has internal threading along the hollowv bore, and internally threaded holes through opposite sides of the bar perpendicular to the hollow bore. The holes are aligned along the bar so as to permit passage of a bolt therethrough. Additionally, the sampling arm coupler device has a lever arm structure having one insert end comprising a half cylinder portion with external threading and a flat longitudinal sure opposite the external threading. The external threading of the half cylinder is capable of mating with the internal threading of the bore whereby the half cylinder portion and the flat longitudinal surface portion inserts and screws into one end of the bar, wherein the flat longitudinal surface portion is positioned as to allow at least one bolt to be inserted through the bar holes perpendicular to the bore along the flat longitudinal surface portion.

Abstract: This invention relates to a system for vibration testing of specimens using n electro-dynamic shaker. It overcomes the various undesirable consequences which attend the existing technology and methodology, which uses a constant thickness flat plate platen, by using an inverted, truncated pyramid type of platen, with both the base and top of square-rectangular-parallelpiped shapes, attached to a cylindrical shaker head. The outer portion of the platen has a very low mass and the section modulus is very high at the line of bending thereby increasing the resonant frequency of the platen while lowering the total weight of the platen, because there is less mass around the perimeter of the platen. The optimum shape of the pyramid is determined by a means which can be expedited by use of the computer program.