High–precision locus function (option)

The high–precision locus function improves the operating performance of the robot in linear and arc operations having a CNT or corner distance specification. Linear positioning operations and joint operation are the same regardless of whether this function is provided.

 Constant locus

By using the high–precision focus function, the robot can move along a constant locus without using the override. For a program taught and tested with a low override value, the robot moves along the same locus even if the override is at 100%.

 Restart operation after a temporary/emergency stop

When a restart operation is performed after a temporary or emergency stop, this function causes the robot to move along the same locus as that along which it would move if the stop was not performed. Although the robot moves along the same locus, the orientation may differ slightly. For the restart operation function, the following system variable must be specified:

– $MH_ORGRSM.$RET_PTH_ENA=TRUE (handling tool)

 Locus precision improvement

This function improves locus precision for linear and arc operations.

 Constant speed

This function can maintain the specified speed when the robot moves around a corner. If the specified speed cannot be maintained due to the operating performance of the robot mechanism, the speed decreases automatically. If the speed around the corner decreases, adjustment is possible using the corner positioning format and the corner speed ratio add instruction.

The corner positioning format and the corner speed ratio add instruction can be edited from the teach pendant as part of a normal program.

 Corner distance specification

This function allows the user to specify the distance between a specified point around a corner and the actual pass point. To specify the distance, use a corner distance specification, not CNT. If CNT 100 is specified, the minimum corner distance that allows the robot to move at a constant speed is assumed.

NOTE Control of the locus/speed for an operation for which CNT format is specified differs depending on whether the high–precision locus function is added. A positioning teaching operation does not differ depending on whether the high–precision locus function is added.

Corner distance specification format L P[1] 100mm/sec CDy.

To adjust the distance between a specified point and the path during the execution of an operation instruction, use the corner distance specification format. When the corner distance specification format is used, the corner distance must be specified.

A corner distance is the distance between a specified point and the path during operation.

Note the following when specifying a corner distance:

 A corner distance is specified in mm units.

 A corner distance must fall within the range of 0 mm to 1000 mm.

 With a shorter corner distance, the robot passes nearer the specified point.

 With a longer corner distance, the robot passes farther from the specified point.

 A corner can never be more than half the distance between the preceding and succeeding specified points.

Figure 4–23. Shows the relationship between a corner distance and an operating path

50mm

100mm Corner distance

P [2]

LP [2] 1000mm/sec Corner 50 LP [2] 1000mm/sec Coner 100

P [1]

start point

P [3]

When a corner distance is specified, an attempt is made to maintain the specified speed around a corner while remaining within the operating capabilities of the robot. If the specified speed cannot be maintained, the robot automatically decelerates. To adjust the corner speed, use the corner speed ratio add instruction.

Corner speed ratio add instruction

When the high–precision locus function is enabled, an attempt is made to maintain the specified speed while remaining within the operating capabilities of the robot. If the specified speed cannot be maintained, the robot automatically decelerates. If the speed decreases around a corner and the speed around the corner needs adjustment, use the corner speed ratio add instruction.

Specifying the corner speed ratio add instruction

 A ratio of 100 causes the robot to operate in exactly the same way as when the corner speed ratio add instruction is not specified.

 If the corner speed ratio add instruction is specified with a parameter greater than 100, the speed around the corner becomes faster than that when the corner speed ratio add instruction is not specified. The speed cannot, however, exceed the specified speed.

 If the corner speed ratio add instruction is specified with a parameter smaller than 100, the speed around the corner becomes slower than that when the corner speed ratio add instruction is not specified.

CAUTION

When the corner speed ratio add instruction is used with a parameter greater than 100, vibration may

Restrictions

Some instructions may cause the robot to decelerate regardless of the positioning format for an operation instruction. For such instructions, corner distance positioning and the corner speed ratio add instruction are ignored and positioning equivalent to CNT 0 is performed.

Instructions that cause the robot to decelerate if Lock position register Instruction/Unlook position register instruction is not used:

 Position register instructions PR[], PR[]INC

 Position compensation add instructions OFFSET, TOOL_OFFSET

Instructions that always cause the robot to decelerate:

 Coordinate system instructions

UFRAME_NUM, UFRAME, UTOOL_NUM, UTOOL

 – Branch instructions

IF SELECT CALL (if the calling and called programs use different motion groups)

 Wait instruction WAIT

 Another instruction Parameter instruction

 Program control instructions ABORT

 Macros

(if the calling program and the called macro use different motion groups)

 Skip condition instructions

 Tracking instructions

 Sensor instructions RCV

 Palletizing instructions PALLETIZIHG_B, PL[]