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The article presents information related to the user-applied forces of human factors engineering (HFE) in mechanical design. It is stated that stabilization, actuation and opposition are the three fundamental forces in tools. It is mentioned that by gripping the device, stabilization of mechanical devices is often accomplished with exception of devices that are immovable. It is noted that to select the preferred grip or grips is a significant early step in mechanical HFE. The article states that static, sliding and viscous are three types of friction to consider in resisting motion.

The author discusses the application of the concept of exact constraint in design engineering. The author explains that the concept allows design engineers to avoid over-constraint designs which are characterized with high stresses, tight tolerances, looseness, binding, and difficult assembly. He cites Brigham Young University Ira A. Fulton College of Engineering and Technology dean Alan R. Parkinson, consulting engineer Lawrence Kamm and book author Douglass Blanding as advocates of the concept. He cites Parkinson explaining that understanding what exact constraint means help every design engineers to perfect the constraint principles.

The article explores the history of friction damper technology in turbine blades by utilizing the centrifugal loading acting on the blade. An integrated approach for the under-platform friction damper design was published by Jerry Griffin in 1980. His idea entails the application of an individual metal piece, which is pressed by the centrifugal load against the platforms of vibrating turbine blade. His findings about the requirements for the design process of friction airfoil damper have opened friction damping technology used by original equipment manufacturers (OEM) in gas and steam turbines.