Delta ASDA-A3 Series User Manual page 297

Motion Control
Cubic Curve
If the master and slave axes operate only based on the corresponding positions, such as the
point-to-point relation, you can use the cubic curve method to create an E-Cam curve. If using
the cubic curve method to create the table, simply enter the E-Cam phase and the
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corresponding slave axis positions to have the tabulation tool automatically connect the points
and optimize the curve. In some applications, you might need a point-to-point cam motion
trajectory such as a constant line or curve, then you can use the cubic curve method to modify
the curve, and set the start angle N1 (the angle departing from the start point) and the end
angle N2 (the angle arriving at the target point) as needed, as shown in Figure 7.3.4.7. There
are three types of curves for creating the table:
Constant speed: a constant-speed linear trajectory connecting two sets of cam point data;
1.
the start and end angles are unadjustable.
Uniform acceleration: a uniform incremental or decremental curve in single direction. Only
2.
the start angle is adjustable.
Cubic curve: the start and end angles are both adjustable. Changing the angles also
3.
changes the speed when departing from the start point and arriving at the target point.
Note that improper angle setting leads to drastic speed change which causes machine
vibration.
Figure 7.3.4.8 is the cubic curve setting interface for creating E-Cam tables in ASDA-Soft. The
steps to create the table with the cubic curve method are as follows:
Set the E-Cam curve: set the E-Cam phase, slave axis position, curve type, start and end
1.
angles in Cubic Data. You can drag the transition points in the cubic curve simulation to
change the corresponding data of each point. When you drag, insert, or delete the
transition points, the corresponding cubic data contents are promptly changed. However, if
you directly enter or select the desired content in the cubic data, you must click Create
Cubic Curve to change the cubic curve simulation.
E-Cam table setting: when completing the transition point setting, set the sampling angle
2.
and click Convert to E-Cam table, so the software will fill in the sampling data to the
E-Cam table. The more the sampling points, the more accurate the cam shapes. If the
setting value for the slave axis is too small, vibration might occur because the decimal
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0°
270°
180°
Figure 7.3.4.7 Start angle and end angle
N2
90° 270°
N1
0°
90°
180°
ASDA-A3