Thesis (Ph.D.)--Florida Institute of Technology, 2000
This dissertation presents research results that advance the design of four-bar mechanisms through computational modeling. The focus is on new methods to better design mechanisms for spatial tasks. Some examples of desired tasks include rigid-body guidance and pick and place operations
The theory developed here synthesizes mechanisms for two, three, and four desired locations. Specifically, we synthesize mechanisms that are useful in practice. Mechanisms that have singularity problems or can not move through the desired locations in the proper order are eliminated. Also mechanisms that have to be re-assembled in order to move through all desired locations have no practical use. Spatial mechanisms that incur link collisions while moving through the desired locations are useless in practice. Furthermore, current mechanism synthesis methods require a lot of guesswork on the part of the engineer and involve extensive trial and error before a useful mechanism is found. This dissertation presents methods to help eliminate these problems
A computational method to help design spherical mechanisms for general spatial tasks is presented. In addition, it is shown how the user can view all possible mechanism designs at one time for a given set of desired locations. This includes spherical mechanism design for three desired orientations. This enables one to pick and choose the mechanism that best fits the needs of the given task. Currently, to design a spherical mechanism for two desired locations, the designer must determine many of the design parameters through trial and error. We present a method to help determine a useful crank-rocker spherical mechanism for two desired locations that requires only a few iterations by the designer. Tests that will determine if a mechanism suffers singularity, assembly, order, or link collision problems are discussed
The process for synthesizing mechanisms can be aided with the use of computers. More specifically, mechanism CAD programs that employ computer graphics with a full featured GUI can help the mechanism design process. All the theory and methods presented here are assembled into a software package called <italic>O</italic><smcap>SIRIS</smcap>
