The goal of this chapter to help you identify how to achieve motion in your mechanical product or machine. The most common motion enabling assemblies are:

• Linkage mechanisms: rigid bodies connected by joints that transmit force and motion.  Linkages can be used for lots of different types of motion, such as linear, rotary, oscillating, and complex.
• Linkage synthesis and motion analysis: methods for finding the dimensions and positions of linkages that satisfy a given motion requirement. There are both graphical and analytical techniques for linkage synthesis and motion analysis.
• Cam and follower assemblies: devices that convert rotary motion into complex or irregular motion. You design the cam profile and select a follower type for the specific application.
• Gearing assemblies: sets of gears that transmit motion and torque between shafts. Choose gear types, sizes, ratios, and arrangements for various purposes, such as speed reduction, power transmission, and direction change.
• Belt and sprocket assemblies: systems that use belts or chains to transmit motion and torque between pulleys or sprockets. Select belt or chain types, sizes, lengths, tensions, and alignments for different scenarios, such as smooth or jerky motion, constant or variable speed, and high or low load.

Section Questions