Omron SYSMAC CJ Series, Operation Manual

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Motion control concepts Section 1-3
8
In applications it can be required for a set of motors to perform a move
operation from one position to another in a straight line. Linearly interpolated
moves can take place among several axes. The commands
MOVE and
MOVEABS are also used for the linear interpolation. In this case the
commands will have multiple arguments to specify the relative or absolute
move for each axis.
Consider the three axis move in a 3-dimensional plane in the figure. It
corresponds to the
MOVE(50,50,50) command. The speed profile of the
motion along the path is given in the diagram. The three parameters SPEED ,
ACCEL and DECEL that determine the multi axis movement are taken from
the corresponding parameters of the base axis. The MOVE command
computes the various components of speed demand per axis.
A is the time axis, B is the speed axis.
1-3-2-2 Circular interpolation
It may be required that a tool travels from the starting point to the end point in
an arc of a circle. In this instance the motion of two axes is related via a
circular interpolated move using the
MOVECIRC command.
Consider the diagram in the figure. It corresponds to the MOVECIRC(-100,0,-
50,0,0) command. The centre point and desired end point of the trajectory
relative to the start point and the direction of movement are specified. The
MOVECIRC command computes the radius and the angle of rotation. Like the
linearly interpolated MOVE command, the ACCEL , DECEL and SPEED
variables associated with the base axis determine the speed profile along the
circular move.
1-3-2-3 CAM control
0 50
50
-50
A
B