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In the automotive industry, thermoplastic snap-fit designs are widely used. For various reasons, the related design analytics have become a subject of special interest. The available references offer a limited scope of effectively using analytical methods. In certain cases, more rigorous assumptions are needed. Closed form solutions as presented in this paper cover all of the important features constituting the global structure of snap-fingers and deliver exact values of deflections and other results. Other methods like Finite Element Analysis (FEA) or graphical computation could also be adopted to fit certain design environments and professional preferences. Snap-fit designs are occasionally required to meet certain installation efforts, and the necessary evaluation can be done analytically or by using a vector diagram. Getting eigenvalues is occasionally difficult. However, column loads and dynamic responses can be estimated by using the Rayleigh-Ritz method of approximation.

Plated terminals are occasionally subjected to concentrated mechanical loads which create a complex stress distribution within the terminal material. To study this phenomenon, a locally loaded semi-infinite medium is considered analogous to the terminal, wherein plating thicknesses and deformations are infinitesimally small. The analysis uses a bipotential function and leads to equations for local stresses and displacements. It also generates several right-circular cones to identify zones of specific characters in terms of displacements and stresses. Cone vertices, with one exception, are different for different materials. Cone generators are of special interest. Regions on some generators do not have any radial stresses, whereas others have no radial displacements. The results are of a fundamental nature and can be used to study a plated terminal substrate under concentrated load.

High terminal-to-terminal insertion efforts have created the need for improving the design of high density interconnection systems. To meet this challenge with a reduced design time schedule systematic analytical work is required. As a result of analytical research, a unique three-phase evaluation procedure is presented. Phase I determines the possible terminal deformations; Phase II estimates the ultimate insertion effort. And finally, Phase III analysis computes the variances in such a force and helps to select the design parameters for an optimum insertion effort with minimum uncertainties. At this stage, it appears imperative that the suggested three-phase analytical concept be accomplished even before any tooling is initiated. The final evaluation, however, must be based on testing of actual parts.