3.1 How to Use Capture Function to Create E-Cam Curves?
3.1.2 About the System and System Configuration
3.1.3.4 Parameter Settings for Slave Axis (Round Compression Axis)
An ASDA-A2 series servo drive is selected as the slave axis in this example. The following explains function of parameter settings.
For DI/O settings please refer to Figure 3.1.5 Wiring Diagram.
P1-01 (Input setting of Control mode and Control Command): Set to 0x01 in PR mode.
P1-44 (Gear Ratio (Numerator)): Default 128.
P1-45 (Gear Ratio (Denominator)): Default 10.
From this setting, we can know that 100000 PUU will be generated when this axis travels one circle.
P1-02 (Speed and Torque Limit Setting): Set to 0x10.
Function to set torque limit will be used to avoid great impact from the compression axis. Range limit will be set by P1-12 (DI setting: TCM0 = 1, TCM1 = 0)
P2-35 (Condition of Excessive Position Control Deviation Warning): The setting value here must be high enough so as to avoid excessive deviation. More details will be explained later.
March, 2015 3-11 Setting Screen for PR#0— Homing
Figure 3.1.9 Setting of PR#0 for the Slave Axis
Set Homing Method to X : 2 : Homing in forward direction: ORGP : OFF-> ON, as homing origin.
Then, Set Single Setting to Y : 0 : Return to Z pulse. When homing is completed, PR stops and set P6-01 which specifies the origin to 0. These settings have to be changed based on different applications.
PR#1 Setting Screen
Figure 3.1.10 Setting Screen of PR#1 for the Slave Axis
In this path, the written target is set to P1-12 and its torque setting is 50%, which can be adjusted depending on circumstances. This PR has set an interrupt command.
PR#2 Setting Screen
Figure 3.1.11 Setting Screen of PR#2 for the Slave Axis
PR#2 is set to control the position, which command is absolute type. See Figure 3.1.11.
PR#5 Setting Screen
March, 2015 3-13 PR#6 Setting Screen
Figure 3.1.13 Setting Screen of PR#6 for the Slave Axis
This PR path is set to a position command which is absolute type. See Figure 3.1.13.
PR#7 Setting Screen
Figure 3.1.14 Setting Screen of PR#7 for the Slave Axis
This path setting is for torque limit.
PR#51 Setting Screen
Figure 3.1.15 Setting Screen of PR #51 for Slave Axis
This is a jump path, which will be carried out when EV1 (Event 1) is triggered by rising-edge.
PR#52 Setting Screen
March, 2015 3-15 PR Program
JUMP DELAY= 0
PR#5
# 5 Write P1-12=25
# 6
Position D= 0, S = 200 rpm - 800000 PUU, ABS
# 7 Write DELAY= 0
P1-12 =10
JUMP PR#1
( I)
DELAY= 0
DELAY= 0 # 1 Write P1-12 =50 DELAY= 0 (I)
# 2
Position D= 0, S= 500 rpm
-300000 PUU, ABS
# 0
Home Offset =0 PR#0 Jump Cmd;
jump to PR#5
Torque Limit;
set to 50%
Position Cmd; move to ABS position -800000
Torque Limit;
set to 10%
Jump Cmd;
jump to PR#1
1 2 3 4
5 6 Torque Limit;
set to 50% 7 Position Cmd; move to ABS position -300000
EV 1
EV 1
PR
# 5 1
PR PR PR
#52
PR PR PR
PR
Figure 3.1.17 PR Program of the Slave Axis
This is how ASDA-A2 deals with commands: when one command is sent, the next PR command will then be sent. It does not wait for the command to be completed and then set the next one.
Below is how the mechanism works according to the PR paths above.
E
0 -300000
-800000
PR#0 1
2 3 4 5 6 7
EV1 EV1
F
C B A
D
DI7
Figure 3.1.18 Slave axis works according to the PR program
Rising-edge Trigger EV1
When the system returns to the origin and after the first time EV1 is triggered by rising-edge, the starting point is A instead of B. From the second time, it will start from point B because it is set to absolute position in the PR path. First of all, set the torque force to 25% before issuing the position command. This is because there will be a bigger striction when motor is started; if torque force is set too small, the motor will not move or move only for a short while and then stop. Once the motor is started successfully, kinetic friction will be rather smaller. Then, use step 4 (PR#7) to decrease the torque force to 10%. This step is for avoiding the round compression axis knocking the rectangle carrier too hard. Then, the compression axis moves to point C but it is never able to reach the target distance D (-800000) due to the obstruction of the rectangle carrier. In this case, the setting value of P2-35 (Condition of Excessive Position Control Deviation Warning) must be bigger than distance F; Otherwise, AL009 (Excessive Deviation of Position Command) might occur. Based on the possible position of the rectangle carrier, distance F in Figure 3.1.18 is the most possible maximum distance that the compression axis can travel. When compression axis reaches position C and stops, this will be the timing for sampling. DI7 has to be switched ON to enable the Capture function and record the position. Capture function will be explained later in section 3.1.3.5.
Falling-edge Trigger EV1
After DI7 is On and sampling is complete, falling-edge trigger EV1 and raise the torque level. Let the compression axis move back to position B. Then, wait for the rectangle carrier to move to the next sampling position. Allow the system repeat the steps from 1 to 7.