Acceleration/Deceleration Processing - Mitsubishi Electric MELSEC iQ-R16MTCPU Programming Manual

Acceleration/deceleration processing

Acceleration/deceleration are processed by the following three methods.
Trapezoidal acceleration/deceleration processing
This is a conventional linear acceleration/deceleration processing. The acceleration/deceleration graph resembles a
trapezoid, as shown in the diagram below.
V
Positioning speed
0
Acceleration time
S-curve acceleration/deceleration processing
S-curve ratio is set as a parameter to smoothly provide acceleration/deceleration processing than trapezoidal acceleration/
deceleration processing. The acceleration/deceleration graph is a sine curve as shown in the diagram below.
Set the S-curve ratio by the parameter block (Page 220 S-curve ratio) or using the servo program.
V
Positioning speed
0
Acceleration time
S-curve ratio set the part of the sine curve used to produce the acceleration and deceleration curve as shown in the diagram
below.
A
B
B/2 B/2
sine curve
S-curve ratio = B/A × 100[%]
5 POSITIONING CONTROL
266
5.1 Basics of Positioning Control
Time
Deceleration time
Deceleration time
V
(Example)
Positioning
speed
S-curve ratio 100[%]
V
Positioning
b
speed
a
S-curve ratio 70[%]
t
t
Time
t
b/a = 0.7
t