Galil DMC-2X00 用户手册

y 123  

 

Speed = 20000 x vin 

The corresponding velocity for the motor is assigned to the VEL variable. 

 

#A 
JG0 
BGA 
#B 
vin=@AN[1] 
vel=vin*20000 
JG vel 
JP #B 
EN 

This system requires the position of the motor to be proportional to the joystick angle.  Furthermore, 
the ratio between the two positions must be programmable.  For example, if the control ratio is 5:1, it 
implies that when the joystick voltage is 5 volts, corresponding to 1024 counts, the required motor 
position must be 5120 counts.  The variable V3 changes the position ratio. 

#A Label 
v3=1024 

Initial position ratio 

DP0 

Define the starting position 

JG0 

Set motor in jog mode as zero 

BGA Start 
#B  
v1=@AN[1] Read 

analog 

input 

v2=v1*v3 

Compute the desired position 

v4=v2-_TPA-_TEA 

Find the following error 

v5=v4*20 

Compute a proportional speed 

JG v5 

Change the speed 

JP #B 

Repeat the process 

EN End 

The continuous dual loop, enabled by the DV1 function is an effective way to compensate for 
backlash.  In some cases, however, when the backlash magnitude is large, it may be difficult to 
stabilize the system.  In those cases, it may be easier to use the sampled dual loop method described 
below. 

This design example addresses the basic problems of backlash in motion control systems.  The 
objective is to control the position of a linear slide precisely.  The slide is to be controlled by a rotary 
motor, which is coupled to the slide by a lead screw.  Such a lead screw has a backlash of 4 micron, 
and the required position accuracy is for 0.5 micron.