Mitsubishi Electronics Q172HCPU, Q173HCPU 6 POSITIONING CONTROL, 6.1.7 Acceleration/deceleration processing, (2) S-curveacceleration/deceleration processing

6 POSITIONING CONTROL

6.1.7 Acceleration/deceleration processing

Acceleration/deceleration are processed by the following two methods.

(1) 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

		t
0
	Deceleration time Time
Acceleration time

(2) S-curve acceleration/deceleration processing

S-curve ratio is set as a parameter to provide gentler acceleration and deceleration than trapezoidal processing. The acceleration/deceleration graph is sinusoidal, as shown in the diagram below.

Set the S-curve ratio in the parameter block (Refer to Section 4.3.2) or using the servo program.

V

Positioning speed

				t
0			Time
	Acceleration time
		Deceleration 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				V
		B			(Example)
	B/2		B/2
					Positioning
					speed
										t
							S-curve ratio 100[%]
					Positioning	V	b		b/a = 0.7
			sine curve		speed
								a
										t
S-curve ratio = B/A				100[%]
							S-curve ratio 70[%]

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