Mitsubishi Electronics Q172HCPU, Q173HCPU Fig. 4.4 Spiral Interpolation, 4 PARAMETERS FOR POSITIONING CONTROL, 4.3.3 Allowable error range for circular interpolation

4 PARAMETERS FOR POSITIONING CONTROL

As shown below, the S-curve ratio setting serves to select the part of the sine curve to be used as the acceleration/deceleration curve.

				V
	A						A
	B		Positioning speed				B
B/2		B/2
								B/A=1.0
									t
						S-curve ratio is 100[%]
					V
		Sine curve	Positioning speed
						B		B/A=0.7
S-curve ratio = B/A 100[%]							A
									t
						S-curve ratio is 70[%]

4.3.3 Allowable error range for circular interpolation

The locus of the arc calculated from the start point address and central point address may not coincide with the set end point address for the central-specified control.

The allowable error range for circular interpolation sets the allowable range for the error between the locus of the arc determined by calculation and the end point address.

If the error is within the allowable range, circular interpolation to the set end point address is executed while also executing error compensation by means of spiral interpolation.

If it exceeds the setting range, an error occurs at the start and positioning does not start. Such an error are set the applicable axis or minor error code area.

	Error
Locus determined by spiral	End point address
interpolation	by calculation

Setting end point address

Start point address Central point address

Fig. 4.4 Spiral Interpolation

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