Emerson Control Techniques FM-4 Reference Manual page 138

Programming module
Table of Contents

Advertisement

FM-4 Programming Module Reference Manual
Cam Number
Use the arrows of the spin box to increment or decrement the Cam Number and view the setup information for that Cam
number. A maximum of 32 different cam tables can be created.
Name
The user can specify a cam name (Cam.#.Name) of up to 12 alphanumeric characters. This allows assigning a descriptive
name to each cam table indicating different machine operations.
Cam Type
Cam type (Cam.#.CamType) allow the user to choose from; Master Follower, Absolute MFI, Incremental MFI, Cubic Spline,
or Time Based Index cams. Most data entries are "Absolute" which means each point is an absolute distance from the start
of the cam table which is an implied zero, although the starting value does not have to be zero. The Incremental MFI (Master/
Follower/Interpolation) has the entries as distance deltas from point to point which means the point is relative to the previous
point.
Master Follower
Master Follower is an Absolute Master Follower with a fixed interpolation type of Linear for each point. This is convenient
when there are many points entered or are importing data from a CAD system. A large number of data points are required for
smooth motion.
Absolute MFI
Absolute MFI allows a different master, follower, and interpolation for each point in the cam. The values are in reference to
the beginning of the cam table (position zero). The master positions must increase from point to point since change in master
position must always be increasing.
The position interpolation types that are valid in this mode are:
Linear – Constant velocity across the complete point.
Square – Velocity increases or decreases linearly across the point. This means that the position changes quadratic across
the point.
S-curve - The velocity and position change along a sinusoidal shape across the point
Cosine – The velocity starts and ends at the same velocity, but increases or decreases along a sinusoidal shape in order
that the proper final position is achieved
Jerk Free – The jerk starts and ends at zero. Jerk increases or decreases in smooth transition.
Incremental MFI
Incremental MFI is different from Absolute MFI in that each point is a delta position. This allows values in the middle to be
modified.
124

Advertisement

Table of Contents
loading

Table of Contents