Owner's manual

7-60 Advanced Programming
7.11 Dynamic Dispense Control
NOTE Dynamic Dispense Control is available on the Axiom X-1000 Series and Spectrum Series
Dispensing Systems.
Dynamic Dispense Control (DDC) allows the programmer to precisely control the valve for more
accurate placement of dots and lines. The DDC microcontroller provides precise control of valve motion
and position. The Axiom X-1000 Series Dispensing Systems utilize a Controller Area Network (CAN)
bus serial architecture of distributed processors, which enabled the introduction of DDC. With CAN
architecture, separate controllers for the Dispensing Head, Conveyor Module, and Operating System
deliver closed-loop control with accuracy and precision.
In addition, linear encoders are mounted on the cable drive for the X- and Y-axes for accurate position
control. The actual position of the dispense pump motor can be precisely controlled for accurate
dispensing of dots and lines. DDC also allows you to control the valve motor’s forward and reverse
speed, as well as the valve motor’s acceleration and deceleration.
7.11.1 DDC Advantages
Advantages of DDC include:
Additional options for controlling the pump
Improved accuracy
Faster dispensing without compromising quality
7.11.2 Why DDC?
High speed line dispensing can cause “dog bone” effect where pump reaches maximum flow rate before
the robot reaches slew. See Figure 7-47. Using DDC to adjust pump acceleration can reduce this effect.
NOTE The “dog bone” phenomenon usually occurs when line speed exceeds 4m/sec
(100 mm/sec). Below this speed, turn-on delay and shut-off distance parameters should
be used. Refer to 6.6 Line Parameters.
Figure 7-47 Actual Dispense Results (6 IPS)
Dog bone reduced
with acceleration
adjustment
Dispensed Line w/
“Dog Bone” effect.