Cam Position Calculation Function; Cam Position Calculation Control Data - Mitsubishi Electric MELSEC iQ-R RD78G4 User Manual

5.5

Cam Position Calculation Function

The cam position is calculated by the program with this function. This function can be used to calculate the cam position for
the synchronous control initial position before starting synchronous control.
Example
The following shows the procedure for synchronous position alignment, in a synchronous system where cam axes 2 and 3 are
synchronized with the cam axis position value per cycle of axis 1.
1.
Calculate the cam axis position value per cycle using this function based on the command position value and the cam
reference position of axis 1.
2.
Calculate the cam axis command position value of axis 2 with this function based on the cam axis position value per
cycle that was calculated in 1).
3.
Calculate the cam axis command position value of axis 3 with this function based on the cam axis position value per
cycle that was calculated in 1).
4.
Execute positioning on axis 2 to the cam axis command position value which was calculated in 2), and also on axis 3 to
the cam axis command position value which was calculated in 3).
5.
Start synchronous control on axis 1, 2 and 3 with the command position value restoration mode. Use the cam axis
position value per cycle that was calculated in 1) for the cam axis position value per cycle (Initial setting).

Cam position calculation control data

Setting item Setting details
[Cd.612] • Set the cam position calculation request.
Cam position • After completion of cam position calculation, "0" is
calculation request automatically stored by the Motion module.
Fetch cycle: Main cycle
[Cd.613] • Set the cam No. for the cam position calculation.
Cam position Fetch cycle: At request (Cam position calculation request)
calculation: Cam No.
[Cd.614] • Set the cam stroke amount for the cam position
Cam position calculation.
calculation: Stroke Fetch cycle: At request (Cam position calculation request)
amount
[Cd.615] • Set the cam axis length per cycle for the cam position
Cam position calculation.
calculation: Cam axis Fetch cycle: At request (Cam position calculation request)
length per cycle
[Cd.616] • Set the cam reference position for the cam position
Cam position calculation.
calculation: Cam Fetch cycle: At request (Cam position calculation request)
reference position
[Cd.617] • Set the cam axis position value per cycle for the cam
Cam position position calculation.
calculation: Cam axis Fetch cycle: At request (Cam position calculation request)
position value per
cycle
[Cd.618] • Set the cam axis command position value for the cam
Cam position position calculation. (Set when calculating the cam axis
calculation: Cam axis position value per cycle.)
command position Fetch cycle: At request (Cam position calculation request)
value
*1 With the exception of positioning control, main cycle processing is executed during the next available time. It changes by status of axis
start.
*2 Output axis position units (Page 123 Units for the output axis)
*3 Cam axis cycle units (Page 123 Units for the output axis)
*1
5 ADVANCED SYNCHRONOUS CONTROL INITIAL POSITION
Setting value
■Set in decimal.
1: Cam axis command position value
calculation request
2: Cam axis position value per cycle calculation
request
■Set in decimal.
0 to 256
■Set in decimal.
-2147483648 to 2147483647
*2
[Output axis position units ]
■Set in decimal.
1 to 2147483647
*3
[Cam axis cycle units ]
■Set in decimal.
-2147483648 to 2147483647
*2
[Output axis position units ]
■Set in decimal.
0 to (Cam axis length per cycle)
*3
[Cam axis cycle units ]
■Set in decimal.
-2147483648 to 2147483647
*2
[Output axis position units ]
5.5 Cam Position Calculation Function
5
Default Buffer
value memory
address
0 53780
0 53781
0 53782
53783
0 53784
53785
0 53786
53787
0 53788
53789
0 53790
53791
159