6.7 Radius-Specified Circular Interpolation Control. Mitsubishi MOTION CONTROLLERS Q172DCPU

6 POSITIONING CONTROL

6.7 Radius-Specified Circular Interpolation Control

Circular interpolation control by specification of the end point address and radius for circular interpolation is executed.

Radius-specified circular interpolation control uses ABS , ABS , ABS and

ABS (Absolute data method) and INC , INC , INC and INC

(Incremental data method) servo instructions.

Items set using MT Developer

Servo instruction

Positioning method

Number of control axes

Speed change

ABS

ABS

ABS

ABS

INC

INC

INC

INC

Absolute

Incremental

2

Valid

: Must be set

: Set if required

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6 POSITIONING CONTROL

[Control details]

Details for the servo instructions are shown in the table below.

Instruction

Rotation direction of the servomotors

Maximum controllable angle of arc

Positioning path

ABS

INC

Clockwise

Start point

Radius R

<180

Positioning path

End point

Central point

0° < < 180°

ABS

INC

Counter clockwise

Central point

Radius R

Start point

<180

End point

Positioning path

Positioning path

ABS

Central point

Clockwise

INC

Radius R

Start point

End point

180° < 360°

ABS

Start point

Radius R End point

Counter clockwise

Central point

INC

Positioning path

Control using ABS , ABS , ABS , ABS (Absolute data method)

(1) Circular interpolation from the current stop address (address before positioning) based on the home position to the specified end address with the specified radius is executed.

(2) The center of the arc is the point of intersection of the perpendicular bisectors of the start point address (current stop address) to the end address.

Forward direction

Positioning speed

Circular interpolation path

End address (X

1

, Y

1

)

Reverse direction 0

Radius R

Start point address (X 0 , Y 0 )

Arc central point

Forward direction

Reverse direction (Note) : Indicates setting data

Fig.6.13 Circular interpolation control using absolute data method

(3) The setting range of end point address is (-2

31

) to (2

31

-1).

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6 POSITIONING CONTROL

(4) The setting range for the radius is 1 to (2

31

-1).

(5) The maximum arc radius is (2

32

-1).

2 31 -1

Maximum arc

0

-2 31

Arc central point Radius R

2 31 -1

Fig.6.14 Maximum arc

Control using INC , INC , INC , INC (Incremental data method)

(1) Circular interpolation from the current stop address (0, 0) to the specified end point with specified radius.

(2) The center of the arc is the point of intersection of the perpendicular bisectors of the start point address (current stop address) to the end address.

Forward direction Circular interpolation path

Positioning speed

End point

Radius R

Start point

Arc central point

Reverse direction

Forward direction

0

Reverse direction (Note) : Indicates setting data

Fig.6.15 Circular interpolation control using incremental data method

(3) Setting range of end point address is (-2

31

) to (2

31

-1).

(4) Setting range of radius is 1 to (2

31

-1).

(5) Maximum arc radius is (2

31

-1).

2 31 -1

Arc central point

0

Maximum arc

-2 31

Radius R

2 31 -1

Fig.6.16 Maximum arc

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6 POSITIONING CONTROL

[Program]

Program for radius-specified circular interpolation control is shown as the following conditions.

(1) System configuration

Radius-specified circular interpolation control of Axis 1 and Axis 2.

Motion CPU control module

Q61P Q03UD

CPU

Q172D

CPU

QX41 QY41 Q172D

LX

Positioning start command (PX000)

AMP

Axis

1 M

AMP

Axis

2 M

AMP

Axis

3 M

AMP

Axis

4 M

(2) Positioning operation details

The positioning uses the Axis 1 and Axis 2 servomotors.

The positioning by the Axis 1 and Axis 2 servomotors is shown in the diagram below.

Axis 2 positioning direction

(Forward direction)

50000

Positioning using the servo program

No.41.

End point (100000, 50000)

30000

Start point

(10000, 30000)

(Reverse

direction)

0

Home position

10000

(Reverse direction)

100000

Arc central point

(3) Positioning conditions

(a) Positioning conditions are shown below.

Item

Positioning method

Positioning speed

Servo Program No.

No.41

Absolute data method

1000

Axis 1 positioning direction

(Forward direction)

(b) Positioning start command ........ PX000 Leading edge (OFF ON)

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6 POSITIONING CONTROL

(4) Operation timing

Operation timing for radius-specified circular interpolation control is shown below.

V

Servo Program No.41

Vector speed t

PLC ready flag (M2000)

All axes servo ON command

(M2042)

All axes servo ON accept flag

(M2049)

Axis 1 servo ready (M2415)

Axis 2 servo ready (M2435)

Start command (PX000)

Servo program start

Axis 1 start accept flag

(M2001)

Axis 2 start accept flag

(M2002)

(5) Servo program

Servo program No.41 for radius-specified circular interpolation control is shown below.

<K 41>

ABS

Axis

Axis

Speed

Radius

1,

2,

100000

50000

1000

80000

Radius specified-circular interpolation control

Axis used . . . . . Axis 1, Axis 2

End address

Axis 1 . . . 100000

Axis 2 . . . . 50000

Positioning speed . . . . . . . . . 1000

Radius . . . . . . . . . . . . . . . 80000

(Note): Example of the Motion SFC program for positioning control is shown next page.

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6 POSITIONING CONTROL

(6) Motion SFC program

Motion SFC program for which executes the servo program is shown below.

Radius specified-circular interpolation control

Radius specified-circular interpolation control

[F10]

SET M2042

[G10]

PX000*M2415*M2435

[K41]

ABS

Axis 1, 100000PLS

Axis 2, 50000PLS

Speed 1000PLS/s

Radius 80000PLS

[G20]

!PX000

Turn on all axes servo ON command.

Wait until PX000, Axis 1 servo ready and Axis 2 servo ready turn on.

Radius specified-circular interpolation control

Axis used . . . . . . . . . . . . . . . Axis 1, Axis 2

End point address

. . . . . . .

Axis 1 . . . 100000[PLS]

Axis 2 . . . . 50000[PLS]

Positioning speed . . . . . . . . . . . . . . . . . . . . . 1000[PLS/s]

Radius . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

80000[PLS]

Wait until PX000 turn off after circular interpolation completion.

END

(Note): Example of the above Motion SFC program is started using the automatic start or PLC program.

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