A computing procedure that can be used to generate follower motions with a higher degree of accuracy by using their digitized 2-D cam surfaces is presented. Based on the geometric relationships at the contact point between a planar cam and its follower, the reverse functions that can be solved to find the follower motion of the cam-follower mechanism are established. To approximate the digitized cam surfaces and to create their derivatives required in determining the follower motions, a least squares periodic B-spline approximation is also introduced. In comparison with analytical results obtained from a theoretical design, the procedure is verified for its accuracy and reliability. Furthermore, by using the cam surface data points taken from a CMM, a practical example is given to show the effectiveness and usefulness of the proposed techniques.

Issue Section:
Technical Papers
Keywords:
motion control, position control, tracking, splines (mathematics), least squares approximations, machine theory, machine tools
Topics:
Approximation, B-splines, Cams, Coordinate measuring machines, Design, Displacement, Errors, Reliability, Rollers, Machine tools, Machinery, Disks, Splines, Manufacturing, Linear systems, Least squares approximations, Mathematics, Motion control, Position control
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 by ASME
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