SUMMARY

ABSTRACT Dielectric materials are used as spacers in antennas. The design of the dielectric determines the properties of the antenna. The insertion of high dielectric materials in a specific pattern into a low dielectric matrix material is one means to accomplish this. This thesis studies the means to insert metal cylinders (wire or nails) into polymer foams to produce such a material. Depending on the antenna properties desired, the patterns and number of nails varies tremendously. To decrease the manufacturing time and, therefore, the cost of creating these materials, an automatic machine capable of rapidly inserting wires to a predetermined pattern is developed. This thesis has two parts. In the first part, the ballistic impact of nails into foam is modeled using FEA techniques. Experimental observations of the nails impacting the foam are used to verify the model. Penetration equations are developed to express the penetration capability of a nail into foam. All of this allows one to predict the forces required for a nail to be inserted into foam to a desired depth, thereby facilitating manufacture of these dielectric materials. In the second part, a fully automatic nail insertion device is designed, fabricated, and tested with the experimental tests used as control settings.