Embedding simple machines to add novel dynamic functions to composites

One unique property of a machine-augmented composite (MAC) is its ability to convert a compressive force into a shear force, and vice versa, simply by the geometry of its angled sidewalls. The authors have discovered that a non-spinning ball dropped at a normal angle onto the MAC’s surface rebounds from that surface at an oblique angle and develops a significant rotational velocity. Through finite-element analyses, analytical study, and experiments, the magnitude and direction of the spin can be precisely controlled by tailoring the stiffness of the MAC through the properties and dimensions of its constituent materials. For more information, contact Gary F. Hawkins, The Aerospace Corporation, P.O. Box 92957 — M2/242, Los Angeles, CA 90009-2957; (310) 336-7379; fax (310) 336-5846; e-mail gary.f.hawkins@aero.org.