interp_cycles.cc

Source code for an Numeric Cmputer

Side effects:
   A number of moves are made as described below. This cycle is a
   modified version of [Monarch, page 5-24] since [NCMS, pages 98 - 100]
   gives no clue as to what the cycle is supposed to do. [KT] does not
   have a back boring cycle. [Fanuc, page 132] in "Canned cycle II"
   describes the G87 cycle as given here, except that the direction of
   spindle turning is always clockwise and step 7 below is omitted
   in [Fanuc].

Called by:
   convert_cycle_xy
   convert_cycle_yz
   convert_cycle_zx

For the XY plane, this implements the following RS274/NGC cycle, which
is usually back boring.  The situation is that you have a through hole
and you want to counterbore the bottom of hole. To do this you put an
L-shaped tool in the spindle with a cutting surface on the UPPER side
of its base. You stick it carefully through the hole when it is not
spinning and is oriented so it fits through the hole, then you move it
so the stem of the L is on the axis of the hole, start the spindle,
and feed the tool upward to make the counterbore. Then you get the
tool out of the hole.

1. Move at traverse rate parallel to the XY-plane to the point
   with x-value offset_x and y-value offset_y.
2. Stop the spindle in a specific orientation.
3. Move the z-axis only at traverse rate downward to the bottom_z.
4. Move at traverse rate parallel to the XY-plane to the x,y location.
5. Start the spindle in the direction it was going before.
6. Move the z-axis only at the given feed rate upward to the middle_z.
7. Move the z-axis only at the given feed rate back down to bottom_z.
8. Stop the spindle in the same orientation as before.
9. Move at traverse rate parallel to the XY-plane to the point
   with x-value offset_x and y-value offset_y.
10. Move the z-axis only at traverse rate to the clear z value.
11. Move at traverse rate parallel to the XY-plane to the specified x,y
    location.
12. Restart the spindle in the direction it was going before.

CYCLE_MACRO has positioned the tool at (x, y, r, a, b, c) before this starts.

It might be useful to add a check that clear_z > middle_z > bottom_z.
Without the check, however, this can be used to counterbore a hole in
material that can only be accessed through a hole in material above it.

For the XZ and YZ planes, this makes analogous motions.

*/

int Interp::convert_cycle_g87(CANON_PLANE plane, //!< selected plane                     
                             double x,  //!< x-value where cycle is executed    
                             double offset_x,   //!< x-axis offset position             
                             double y,  //!< y-value where cycle is executed    
                             double offset_y,   //!< y-axis offset position             
                             double r,  //!< z_value of r_plane                 
                             double clear_z,    //!< z-value of clearance plane         
                             double middle_z,   //!< z-value of top of back bore        
                             double bottom_z,   //!< value of z at bottom of cycle      
                             CANON_DIRECTION direction) //!< direction spindle turning at outset
{
  static char name[] = "convert_cycle_g87";

  CHK(((direction != CANON_CLOCKWISE) &&
       (direction != CANON_COUNTERCLOCKWISE)),
      NCE_SPINDLE_NOT_TURNING_IN_G87);

  cycle_traverse(plane, offset_x, offset_y, r);
  STOP_SPINDLE_TURNING();
  ORIENT_SPINDLE(0.0, direction);
  cycle_traverse(plane, offset_x, offset_y, bottom_z);
  cycle_traverse(plane, x, y, bottom_z);
  if (direction == CANON_CLOCKWISE)
    START_SPINDLE_CLOCKWISE();
  else
    START_SPINDLE_COUNTERCLOCKWISE();
  cycle_feed(plane, x, y, middle_z);
  cycle_feed(plane, x, y, bottom_z);
  STOP_SPINDLE_TURNING();
  ORIENT_SPINDLE(0.0, direction);
  cycle_traverse(plane, offset_x, offset_y, bottom_z);
  cycle_traverse(plane, offset_x, offset_y, clear_z);
  cycle_traverse(plane, x, y, clear_z);
  if (direction == CANON_CLOCKWISE)
    START_SPINDLE_CLOCKWISE();
  else
    START_SPINDLE_COUNTERCLOCKWISE();

  return INTERP_OK;
}

/****************************************************************************/

/*! convert_cycle_g88

Returned Value: int
   If the spindle is not turning clockwise or counterclockwise, this
   returns NCE_SPINDLE_NOT_TURNING_IN_G88.
   Otherwise, it returns INTERP_OK.

Side effects: See below

Called by:
   convert_cycle_xy
   convert_cycle_yz
   convert_cycle_zx

For the XY plane, this implements the following RS274/NGC cycle,
which is usually boring:
1. Move the z-axis only at the current feed rate to the specified z-value.
2. Dwell for the given number of seconds.
3. Stop the spindle turning.
4. Stop the program so the operator can retract the spindle manually.
5. Restart the spindle.

CYCLE_MACRO has positioned the tool at (x, y, r, a, b, c) when this starts.

For the XZ and YZ planes, this makes analogous motions.

*/

int Interp::convert_cycle_g88(CANON_PLANE plane, //!< selected plane                     
                             double x,  //!< x-value where cycle is executed    
                             double y,  //!< y-value where cycle is executed    
                             double bottom_z,   //!< value of z at bottom of cycle      
                             double dwell,      //!< dwell time                         
                             CANON_DIRECTION direction) //!< direction spindle turning at outset
{
  static char name[] = "convert_cycle_g88";

  CHK(((direction != CANON_CLOCKWISE) &&
       (direction != CANON_COUNTERCLOCKWISE)),
      NCE_SPINDLE_NOT_TURNING_IN_G88);

  cycle_feed(plane, x, y, bottom_z);
  DWELL(dwell);
  STOP_SPINDLE_TURNING();
  PROGRAM_STOP();               /* operator retracts the spindle here */
  if (direction == CANON_CLOCKWISE)
    START_SPINDLE_CLOCKWISE();
  else
    START_SPINDLE_COUNTERCLOCKWISE();

  return INTERP_OK;
}

/****************************************************************************/

/*! convert_cycle_g89

Returned Value: int (INTERP_OK)

Side effects: See below

Called by:
   convert_cycle_xy
   convert_cycle_yz
   convert_cycle_zx

This implements the following RS274/NGC cycle, which is intended for boring:
1. Move the z-axis only at the current feed rate to the specified z-value.
2. Dwell for the given number of seconds.
3. Retract the z-axis at the current feed rate to clear_z.

CYCLE_MACRO has positioned the tool at (x, y, r, a, b, c) when this starts.

For the XZ and YZ planes, this makes analogous motions.

*/

int Interp::convert_cycle_g89(CANON_PLANE plane, //!< selected plane                  
                             double x,  //!< x-value where cycle is executed 
                             double y,  //!< y-value where cycle is executed 
                             double clear_z,    //!< z-value of clearance plane      
                             double bottom_z,   //!< value of z at bottom of cycle   
                             double dwell)      //!< dwell time                      
{
  cycle_feed(plane, x, y, bottom_z);
  DWELL(dwell);
  cycle_feed(plane, x, y, clear_z);

  return INTERP_OK;
}

/****************************************************************************/

/*! convert_cycle

Returned Value: int
   If any of the specific functions called returns an error code,
   this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The r-value is not given the first time this code is called after
      some other motion mode has been in effect:
      NCE_R_CLEARANCE_PLANE_UNSPECIFIED_IN_CYCLE
   2. The l number is zero: NCE_CANNOT_DO_ZERO_REPEATS_OF_CYCLE
   3. The currently selected plane in not XY, YZ, or XZ.
      NCE_BUG_PLANE_NOT_XY_YZ_OR_XZ

Side effects:
   A number of moves are made to execute a canned cycle. The current
   position is reset. The values of the cycle attributes in the settings
   may be reset.

Called by: convert_motion

This function makes a couple checks and then calls one of three
functions, according to which plane is currently selected.

See the documentation of convert_cycle_xy for most of the details.

*/

int Interp::convert_cycle(int motion,    //!< a g-code between G_81 and G_89, a canned cycle
                         block_pointer block,   //!< pointer to a block of RS274 instructions      
                         setup_pointer settings)        //!< pointer to machine settings                   
{
  static char name[] = "convert_cycle";
  CANON_PLANE plane;
  int status;

  plane = settings->plane;
  if (block->r_flag == OFF) {
    if (settings->motion_mode == motion)
      block->r_number = settings->cycle_r;
    else
      ERM(NCE_R_CLEARANCE_PLANE_UNSPECIFIED_IN_CYCLE);
  }

  CHK((block->l_number == 0), NCE_CANNOT_DO_ZERO_REPEATS_OF_CYCLE);
  if (block->l_number == -1)
    block->l_number = 1;

  if (plane == CANON_PLANE_XY) {
    CHP(convert_cycle_xy(motion, block, settings));
  } else if (plane == CANON_PLANE_YZ) {
    CHP(convert_cycle_yz(motion, block, settings));
  } else if (plane == CANON_PLANE_XZ) {
    CHP(convert_cycle_zx(motion, block, settings));
  } else
    ERM(NCE_BUG_PLANE_NOT_XY_YZ_OR_XZ);

  settings->cycle_l = block->l_number;
  settings->cycle_r = block->r_number;
  settings->motion_mode = motion;
  return INTERP_OK;
}

/****************************************************************************/

/*! convert_cycle_xy

Returned Value: int
   If any of the specific functions called returns an error code,
   this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The z-value is not given the first time this code is called after
      some other motion mode has been in effect:
      NCE_Z_VALUE_UNSPECIFIED_IN_XY_PLANE_CANNED_CYCLE
   2. The r clearance plane is below the bottom_z:
      NCE_R_LESS_THAN_Z_IN_CYCLE_IN_XY_PLANE
   3. the distance mode is neither absolute or incremental:
      NCE_BUG_DISTANCE_MODE_NOT_G90_OR_G91
   4. G82, G86, G88, or G89 is called when it is not already in effect,
      and no p number is in the block:
      NCE_DWELL_TIME_P_WORD_MISSING_WITH_G82
      NCE_DWELL_TIME_P_WORD_MISSING_WITH_G86
      NCE_DWELL_TIME_P_WORD_MISSING_WITH_G88
      NCE_DWELL_TIME_P_WORD_MISSING_WITH_G89
   5. G83 is called when it is not already in effect,
      and no q number is in the block: NCE_Q_WORD_MISSING_WITH_G83
   6. G87 is called when it is not already in effect,
      and any of the i number, j number, or k number is missing:
      NCE_I_WORD_MISSING_WITH_G87
      NCE_J_WORD_MISSING_WITH_G87
      NCE_K_WORD_MISSING_WITH_G87
   7. the G code is not between G_81 and G_89.
      NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED

Side effects:
   A number of moves are made to execute the g-code

Called by: convert_cycle

The function does not require that any of x,y,z, or r be specified in
the block, except that if the last motion mode command executed was
not the same as this one, the r-value and z-value must be specified.

This function is handling the repeat feature of RS274/NGC, wherein
the L word represents the number of repeats [NCMS, page 99]. We are
not allowing L=0, contrary to the manual. We are allowing L > 1
in absolute distance mode to mean "do the same thing in the same
place several times", as provided in the manual, although this seems
abnormal.

In incremental distance mode, x, y, and r values are treated as
increments to the current position and z as an increment from r.  In
absolute distance mode, x, y, r, and z are absolute. In g87, i and j
will always be increments, regardless of the distance mode setting, as
implied in [NCMS, page 98], but k (z-value of top of counterbore) will
be an absolute z-value in absolute distance mode, and an increment
(from bottom z) in incremental distance mode.

If the r position of a cycle is above the current_z position, this
retracts the z-axis to the r position before moving parallel to the
XY plane.

In the code for this function, there is a nearly identical "for" loop
in every case of the switch. The loop is the done with a compiler
macro, "CYCLE_MACRO" so that the code is easy to read, automatically
kept identical from case to case and, and much shorter than it would
be without the macro. The loop could be put outside the switch, but
then the switch would run every time around the loop, not just once,
as it does here. The loop could also be placed in the called
functions, but then it would not be clear that all the loops are the
same, and it would be hard to keep them the same when the code is
modified.  The macro would be very awkward as a regular function
because it would have to be passed all of the arguments used by any of
the specific cycles, and, if another switch in the function is to be
avoided, it would have to passed a function pointer, but the different
cycle functions have different arguments so the type of the pointer
could not be declared unless the cycle functions were re-written to
take the same arguments (in which case most of them would have several
unused arguments).

The motions within the CYCLE_MACRO (but outside a specific cycle) are
a straight traverse parallel to the selected plane to the given
position in the plane and a straight traverse of the third axis only
(if needed) to the r position.

The CYCLE_MACRO is defined here but is also used in convert_cycle_yz
and convert_cycle_zx. The variables aa, bb, and cc are used in
CYCLE_MACRO and in the other two functions just mentioned. Those