AI contour control, Specifications Additional Manual Page 7

Additional Manual

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TITLE

FANUC

16/18

16i/18i

AI contour control function

Specifications

EDIT. DATE DESIG. DESCRIPTION

FANUC LTD



SHEET

7/ 32

DRAW. NO.

A-63512EN



CUST.

2.5 Feedrate clamp based on acceleration

As shown below, when a curve is formed by very short successive line segments, there is no

significant feedrate difference along each axis at each corner. Consequently, the tool need not

be decelerated to compensate for feedrate differences. When taken as a whole, however,

successive feedrate differences generate a large acceleration along each axis.

In this case, the tool must be decelerated to minimize the stress and strain imposed on the

machine, as well as the machining error that may result from such excessive acceleration. The

tool is decelerated to the feedrate at which the acceleration along each axis, found from the

formula below, is equal to or less than a specified allowable acceleration.

The allowable acceleration is determined from a maximum cutting feedrate (set in parameter

No.1432) and the time needed to reach the maximum cutting feedrate (set in parameter

No.1785).

Acceleration along each axis =

feedrate difference along each axis at a corner

max

travel in the previous block

travel in the next block













The reduced feedrate required for each corner is calculated. The tool is decelerated to the

decreased feedrate found at either the start point or the end point of each block, whichever is

smaller.

(Example) In the example shown below, the tool is decelerated from N2 to N4 and from N6 to

N8 because the acceleration (as indicated by the dashed-line inclinations in the

feedrate graphs) is large.

Contents Summary of AI contour control, Specifications Additional Manual

Page 1FANUC Series 16/18-MC FANUC Series 16i/18i-MA AI contour control Specifications Contents 1. OUTLINE...............................................................................................................2 2. SPECIFICATION........................................................................
Page 21. Outline This function is designed for high-speed precise machining. With this function, the delay due to acceleration / deceleration and the delay in the servo system which increase as the feedrate becomes higher can be suppressed. And the errors in the machining profile can be reduced. The maxim
Page 32.3 Look ahead linear acceleration / deceleration before interpolation When feed per minute is specified, this function reads maximum 40 blocks ahead to perform linear acceleration / deceleration before interpolation, that is, to apply acceleration / deceleration to the specified feedrate. When acce
Page 4(Example of deceleration) To ensure that the feedrate specified for a block is reached when the block is executed, deceleration is started in the previous block. Feedrate Specified feedrate P1 F3 Feed after acceleration / deceleration before interpolation is applied P2 F2 F1 Time N1 N2 To reduce fee
Page 52.4 Automatic corner deceleration The feedrate at a corner is calculated for the axis for which the permissible feedrate difference between two blocks ( parameter No.1783 ) is exceeded with the highest ratio of actual feedrate difference to permissible feedrate difference, as shown below. The feedra
Page 6N1 G01 G91 X100. F1000 ; Tool path when the tool N2 N2 Y100. ; does not decelerated at the corner Tool path when the tool decelerates at the corner N1 Feedrate When the tool does not decelerate at the corner When the tool decelerates at the corner Feedrate F1000 along the X-axis F500 N1 Time Feedra
Page 72.5 Feedrate clamp based on acceleration As shown below, when a curve is formed by very short successive line segments, there is no significant feedrate difference along each axis at each corner. Consequently, the tool need not be decelerated to compensate for feedrate differences. When taken as a w
Page 8Feedrate along the X-axis Feedrate along the Y-axis Feedrate along the tangent to the path N1 N5 N9 N1 N5 N9 TITLE FANUC Series 16/18-MC,16i/18i-MA AI contour control function Specifications DRAW. NO. CUST. A-63512EN SHEET EDIT. DATE DESIG. DESCRIPTION FANUC LTD 8/ 32
Page 92.6 Feedrate clamp based on arc radius In order that the acceleration in a circular interpolation block must become a permissible value, the maximum permissible feedrate v for the programmed circle radius r is calculated from the maximum permissible feedrate V (parameter setting) in radius R as foll
Page 10In case of bell-shaped type acceleration / deceleration The parameter No.1621 (Time constant t used for bell-shaped acceleration / deceleration in rapid traverse for each axis ) of the axis that the value which is calculated by the above expression is the smallest value becomes effective to the fee
Page 11Feedrate F/A :Time for acceleration at linear type T :Time for bell type Time T/2 F/A T/2 T T (Note1) The overlapping rapid traverse blocks is ineffective. (Note2) In case of using bell-shaped type acceleration / deceleration, the option of rapid traverse bell-shaped acceleration / deceleration
Page 12To do smooth machining, it should be controlled to become the feedrate which actual cutting feedrate is specified. With this function, when the offset is the inside, it calculates a override value corresponding to the curvature of the involute curve which changes during the involute interpolation. A
Page 13In case of Rlmt1 > Rcp ± Rofs ≥ Rlmt2 100 - OVR2 OVRb = × ( Rcp ± Rofs - Rlmt2 ) + OVR2 Rlmt1 - Rlmt2 In case of Rlmt2 > Rcp ± Rofs ≥ Rlmt3 OVR2 - OVR3 OVRb = × ( Rcp ± Rofs - Rlmt3 ) + OVR3 Rlmt2 - Rlmt3 In case of Rlmt3 > Rcp ± Rofs ≥ Rlmt4 OVR3 - OVR4 OVRb = × ( Rcp ± Rofs - Rlmt4 ) + OVR4 Rlmt3
Page 14(Note4) When there is an end point error, the remainder distance that is necessary for the acceleration / deceleration before interpolation may be gotten incorrectly. In this case, the alarm 242 is generated. (Note5) As for the other limitation items, please refer to the OPERATOR’S MANUAL. 2.9 Speci
Page 15Item Function Tapping mode (G63) X Automatic corner override (G62) X Linear interpolation (G01) O Circular interpolation (G02, G03) O (Multi-quadrant is possible.) Helical interpolation (G02, G03) O (Circular interpolation + max 4 axes linear interpolation) In case of circular interpolation plus max
Page 16Item Function Floating reference position return O (Note1,2) (G30.1) Canned cycles (G73~G89) O (Note1,2) Rigid tapping O (Note2) Return to initial point (G98) / O (Note1) Return to R point (G99) Normal direction control X (G41.1, G42.1) Continuous dressing X Infeed control (G161) X Index table index
Page 17One-digit F code feed X (Model-C) (3) O (i series) (Note2) However, the feedrate can not be changed by the manual pulse generator. Inverse time feed (G93) O (Note2) External deceleration O (Note2) Program input O :It is possible to command. X :It is not possible to command. Item Function Plane selec
Page 18Tool compensation O :It is possible to command. X :It is not possible to command. Item Function Cutter compensation C O (Note2) (G40, G41, G42) Tool length compensation O (G43, G44, G49) Others O :It is possible to command. X :It is not possible to command. Item Function Cycle start / Feed hold O Dr
Page 19Item Function Machine lock O (When the machine lock signal for each axis (MLK1 ~ MLK8) is operated, the acceleration / deceleration of the axis to which the machine lock is done is ineffective.) Control in / out O Optional block skip (/n) O Miscellaneous function (Mxxxx) O (A code signal and a strob
Page 202.10 Conditions to enter AI contour control mode The modal data when G05.1 P1 is specified should be as follows. If these conditions are not filled, the alarm No.5111 occurs. G code Meaning G00 Positioning G01 Linear interpolation G02 Circular interpolation / Helical interpolation (CW) G03 Circular
Page 213. Parameter 3.1 Acceleration / deceleration before interpolation 1770 Parameter 1 for setting an acceleration for linear acceleration / deceleration before interpolation (maximum machining speed during linear acceleration / deceleration before interpolation) Data type : 2-word Unit of data : Increm
Page 221784 Feedrate when overtravel alarm has occurred during acceleration / deceleration before interpolation Data type : Word axis Unit of data : Increment system Unit of data Valid range Valid range : IS-A, IS-B IS-C Millimeter machine 1 mm/min 6 ~ 15000 6 ~ 12000 Inch machine 0.1 inch/min 6 ~ 6000 6 ~
Page 23(Note1) This parameter is ineffective for G00 block. (Note2) When 0 is set in this parameter, the control described above is not executed. (Note3) When the stored stroke limit check is ineffective, the control described above is ineffective. (Note4) The control described above is applicable only to
Page 243.4 Feedrate clamp based on arc radius 1731 Arc radius value corresponding to a maximum feedrate Data type : 2-word Unit of data : Increment system IS-A IS-B IS-C Unit Millimeter machine 0.01 0.001 0.0001 mm Inch machine 0.001 0.0001 0.00001 inch Valid range : 1000 ~ 99999999 In this parameter, set
Page 251732 Minimum value (RVmin) for feedrate clamp based on arc radius Data type : Word Unit of data : Increment system Unit of data Valid range Valid range : IS-A, IS-B IS-C Millimeter machine 1 mm/min 0 ~ 15000 0 ~ 12000 Inch machine 0.1 inch/min 0 ~ 6000 0 ~ 4800 The feedrate clamp based on arc radius
Page 265616 The override value when beginning the near basic circle override 2 (OVR2) 5617 The override value when beginning the near basic circle override 3 (OVR3) 5618 The override value when beginning the near basic circle override 4 (OVR4) 5619 The override value when beginning the near basic circle ov
Page 273.6 Others 1422 Maximum cutting feedrate in AI contour control mode Data type : 2-word Unit of data : Increment system Unit of data Valid range Valid range : IS-A, IS-B IS-C Millimeter machine 1 mm/min 0 ~ 240000 0 ~ 100000 Inch machine 0.1 inch/min 0 ~ 9600 0 ~ 4000 In this parameter, set the maxim
Page 28Set of the following figure. When the setting value is 0, the acceleration/deceleration becomes linear-shaped acceleration/deceleration. feedrate Linear type acceleration / deceleration Bell-shaped type acceleration / deceleration ta It depends on linear type acceleration. tb Bell type time const
Page 29#7 #6 #5 #4 #3 #2 #1 #0 7052 NMI Data type : Bit axis (2) In case of PMC-controlled axis or Cs axis, set this parameter to “1”. In case that follow up is available for Index table indexing axis(4th axis), set this parameter to 1. (i Series) However, when the FAD function of servo is used, set this p
Page 30(3) Feedrate clamp based on acceleration Meaning of parameter Parameter No. Normal Look-ahead AI contour Allowable acceleration determination - - 1785 (4) Feedrate clamp based on arc radius Meaning of parameter Parameter No. Normal Look-ahead AI contour Arc radius value corresponding to a 1731 maxim
Page 314. Signal AI contour control mode signal AICC (2) [Classification] Output signal [Function] Informs that is in the AI contour control mode. [Output condition] The signal is 1 in the following case : - It is the AI contour control mode. The signal is 0 in the following case : - It is not the
Page 326. Note (1) When this function is used, the option of the AI contour control is needed. And when there is the AI contour control option, it is possible to specify the look-ahead control (G08 P1). (2) The deceleration of the axis is started when the total travel of the axis in the blocks read in adva