This new textbook targets the Junior-Senior level sequence in machine design challenging classical machine design texts associated with authors such as Joseph E. Shigley, Robert C. Juvinall, and Merhyle F. Spotts. The author's emphasis on failure prevention includes the selection of a factor of safety as part of the design process. The book is divided into two parts. The first part addresses engineering principles whereas the second part considers design applications. The first part diverges from similar machine design texts by targeting failure prevention as the underlying theme for machine component selection. The many components of failure are introduced early in Chapter 2. These concepts include the classical failure modes; yielding, ductile and brittle failure, fatigue failure, wear, impact, and buckling along with less traditional failure modes such as fretting, creep, and corrosion are presented. Specifically, the fracture mechanics approach to predict fatigue failure is introduced and expanded from classical texts on machine elements to provide a more modern assessment of fatigue life. The second part provides a classical treatment on the design of machine elements such as bearings, springs, fasteners and power screws, gear pairs, brakes and clutches by presenting established

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Three laws of gearing are presented in terms of a three link 1-dof spatial direct contact mechanism. The first law of gearing defines the instantaneous relationship between an infinitesimal displacement of an output body to an infinitesimal angular displacement of an input body for a specified tooth contact normal. A system of cylindroidal coordinates are introduced to facilitate a universal methodology to parameterize the kinematic geometry of generalized motion transmission between skew axes. The second law of gearing establishes a relation between the instantaneous gear ratio and the apparent radii of the hyperboloidal pitch surface in contact as parameterized using a system of cylindroidal coordinates. The third law of gearing establishes an instantaneous relationship for the relative curvature of two conjugate surfaces in direct contact and shows that this relation is independent of the tooth profile geometry. These three laws of gearing along with the system of cylindroidal coordinates establish, in part, a generalized geometric theory comparable to the existing theory for planar kinematics.

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A methodology is presented where noncircular gears are used to reduce unwanted torque and speed fluctuations that may exist in rotating shafts. A noncircular gear pair is used to drive an auxiliary shaft where a flywheel is mounted, thus creating an auxiliary torque fluctuation. The form of the undesirable torque fluctuation is used to determine a motion specification for the synthesis of a noncircular gear pair. The undesired torque fluctuation and the auxiliary torque fluctuation are added to reduce the net torque fluctuation. Two illustrative examples are included. This approach of torque balancing is compared to the classical method of mounting a flywheel onto the shaft that experiences the unwanted torque fluctuation to reduce its speed variation.