Cam with Edge Selection
Figure 3-2: Example of a cam-follower with cam having edge selection.
Connection Constraint
The following constraint is added in order to impose the cam and follower connection:
In case the connection is conditionally active, the constraint expression is modified to the following:
Here Δ is the connection tolerance. The gap and slip used in the connection constraint are defined in the following section.
Gap and Slip Definition
The gap variable is a measure of displacement vector between the follower point and its closest point on cam boundaries.
The slip variable is a measure of distance between the follower point and its closest point on cam boundaries in spatial tangent direction. Hence it is used to activate or deactivate connection constraint based on the specified connection tolerance.
The gap and slip between the follower point and cam edges can be defined as:
Here
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xf is the spatial position of the follower point.
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xc is the spatial position of a closest point on the cam edges.
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t1c is the spatial tangent of a closest point on the cam edges.
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Xoffset is the initial offset or gap vector between the follower point and cam edges.
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t10c is the material tangent of a closest point on the cam edges.
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Rc is the rotation matrix of the cam.