Festo Контроллер позиционирования CPX-CMAX - Manual (Page 379)

B. Basic controlling principles
B−37
Festo P.BE−CPX−CMA X−CONTROL−EN en 0908NH
m
delta
= m
current tool mass
+ m
current workpiece mass
ć m
ident.
m
delta
= m
current tool mass
+ m
current workpiece mass
ć (m
workpiece mass ident.
+ m
workpiece mass ident.
)
F
piston
= F
setpoint
+ F
0
+ m
delta
* g * sin α
In the simplest case, the following applies:
m
current tool mass
= m
tool mass ident.
m
workpiece mass ident.
= 0 kg
This simplifies calculation for:
m
delta
= m
current workpiece mass
F
piston
= F
setpoint
+ F
0
+ m
current workpiece mass
* g * sin α
What does this mean in terms of force control?
ć It is not necessary for the mass m
ident
specified during
identification to be exact, since the force F
0
required for
compensation is identified.
ć If the drive is not mounted horizontally ( α š 0° ), it is imĆ
portant to specify the mass changes precisely. Since the
controller calculates a compensation force based on the
specified mass, an error in the mass specification will lead
to a systematic deviation from the force setpoint value
F
setpoint
.
F
piston
= F
setpoint
+ F
0
+ (m
delta
+ m
error
) * g * sin α
ć Error F will then be:
F = m
error
* g * sin α