6. LINKAGE SYNTHESIS
· The large number of possible ways to satisfy design criteria make it hard for us to select a single useful mechanism.
· The design techniques outlined below can help narrow down, or select a specific mechanism.
· To do the design work we typically begin with some functional specifications for a path of motion. These specifications typically include one or more of the following,
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- rotational motions (i.e. shaft)
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- differing advance/return times
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- small stop/dwell times
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- straight line segments in path
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- specific velocities along path
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- a curved path
· Some points of interest about the selection of linkages in design,
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- linkages can be used in place of cams to,
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reduce forces
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eliminate loading spring
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simplify manufacture and tolerance problems
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- the space required for these linkages may be larger than cams
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- in many cases ratios are specified. After we get these we will design the weakest member to be mechanically adequate, and then design the other parts.