HEIDENHAIN iTNC 530 HSCI - Realization

636 HEIDENHAIN Technical Manual iTNC 530 HSCI
Realization
For the coupling functions (PLC module 9228), the resolution of the nominal
positions in the PLC module is 0.0001°. The trigonometric functions sin(),
cos(), tan(), etc. require data input in radians (360° = 2*pi).
The inverse trigonometry functions supply the result in radians. To obtain the
radian values from the nominal positions in internal-resolution form, the
position value of the axis must be multiplied by pi / 1800 000 or in shorter form
by pi/18e5.
Hence, the value of an inverse trigonometry function must be multiplied by
18e5/pi to obtain the internal coordinate resolution.
The constants h , ma and mb result from the given mechanical design.
The example using the values h = 1.6 , ma=1, mb=1.6 results in the
synchronous function being called in the PLC program (the error handling is
missing here) as follows:
LBL MF49 ;activate the coupling function
L S" -a + asin(1 - 1/1.6*sin(a*pi/18e5))*18e5/pi"
= S0
PS K0 ;string number
PS K4 ;axis
PS K1 ;mode: Switch-on
CM 9228
PLX
;coupling function for additional picker axis
L S" - asin(1 - 1/1.6*sin(a*pi/18e5))*18e5/pi "
= S0
PS K0 ;string number
PS K5 ;axis
PS K1 ;mode: Switch-on
CM 9228
PLX
EM
The following process must be realized by the PLC program:
 Positioning the PLC axis to a suitable starting position
 Activating the coupling function
 Moving the first PLC axis appropriately (by means of positioning movements
through the PLC), the other PLC axes are automatically corrected.
 Deactivating the coupling function when the respective positioning
movement has been completed
When activating the coupling function you should set the software limit
switches of the principal such that also the coupled axes that are not
monitored cannot exceed the actual limit position. When you rescind the
coupling function, you must set the default values of the software limit
switches again.
Note
For the coupled axis (axes), the software limit switches are not monitored!