3diy
/
klipper
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

extruder: Do extruder lookahead based on time instead of cornering 

When calculating the extruder lookahead, determine how far to
lookahead by the amount of elapsed time each move takes.  This makes
the extruder lookahead code more flexible as it is no longer limited
to the next immediate cornering moves.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
This commit is contained in:
Kevin O'Connor 2017-01-27 22:32:12 -05:00
parent 1bb7a22115
commit 528c29c01c
2 changed files with 37 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

75
klippy/extruder.py
View File

@ -38,6 +38,7 @@ class PrinterExtruder:
self.need_motor_enable = True
def check_move(self, move):
move.extrude_r = move.axes_d[3] / move.move_d
move.extrude_max_corner_v = 0.
if not self.heater.can_extrude:
raise homing.EndstopMoveError(
move.end_pos, "Extrude below minimum temp")
@ -60,30 +61,34 @@ class PrinterExtruder:
return 0.
move.extrude_r = prev_move.extrude_r
return move.max_cruise_v2
def lookahead(self, move_info, orig_flush_count, lazy):
if not self.pressure_advance:
return orig_flush_count
min_corner_v2 = max_corner_v2 = 0.
flush_count = len(move_info)
for i in range(flush_count-1, -1, -1):
move, start_v2, cruise_v2, end_v2 = move_info[i]
reachable_start_v2 = end_v2 + move.delta_v2
# Calculate min/max_corner_v2 - the speed the head will
# slow to due to junction cornering and the maximum speed
# the head will reach immediately afterwards.
move.extruder_min_corner_v2 = min_corner_v2
move.extruder_max_corner_v2 = max_corner_v2
if reachable_start_v2 > start_v2:
min_corner_v2 = start_v2
if (start_v2 + move.delta_v2 > end_v2
or end_v2 >= move_info[i+1][2]):
if lazy and max_corner_v2:
flush_count = i
lazy = False
max_corner_v2 = cruise_v2
if lazy:
return 0
return min(flush_count, orig_flush_count)
def lookahead(self, moves, flush_count, lazy):
pressure_advance = self.pressure_advance
if not pressure_advance:
return flush_count
# Calculate max_corner_v - the speed the head will accelerate
# to after cornering.
for i in range(flush_count):
move = moves[i]
if not move.decel_t:
continue
cruise_v = move.cruise_v
max_corner_v = 0.
sum_t = pressure_advance
for j in range(i+1, flush_count):
fmove = moves[j]
if not fmove.max_start_v2:
break
max_corner_v = max(max_corner_v, fmove.cruise_v)
if max_corner_v >= cruise_v:
break
sum_t -= fmove.accel_t + fmove.cruise_t + fmove.decel_t
if sum_t <= 0.:
break
else:
if lazy:
return i
move.extrude_max_corner_v = max_corner_v
return flush_count
def move(self, move_time, move):
if self.need_motor_enable:
self.stepper.motor_enable(move_time, 1)
@ -108,28 +113,20 @@ class PrinterExtruder:
if (axis_d >= 0. and (move.axes_d[0] or move.axes_d[1])
and self.pressure_advance):
# Increase accel_d and start_v when accelerating
move_extrude_r = move.extrude_r
pressure_advance = self.pressure_advance * move.extrude_r
prev_pressure_d = start_pos - move.start_pos[3]
if accel_t:
npd = move.cruise_v * move_extrude_r * self.pressure_advance
if accel_d:
npd = move.cruise_v * pressure_advance
extra_accel_d = npd - prev_pressure_d
if extra_accel_d > 0.:
accel_d += extra_accel_d
start_v += extra_accel_d / accel_t
prev_pressure_d += extra_accel_d
# Update decel and retract parameters when decelerating
if decel_t:
if move.extruder_min_corner_v2:
min_corner_v = math.sqrt(move.extruder_min_corner_v2)
max_corner_v = math.sqrt(move.extruder_max_corner_v2)
npd = max_corner_v*move_extrude_r*self.pressure_advance
extra_decel_d = prev_pressure_d - npd
if move.end_v > min_corner_v:
extra_decel_d *= ((move.cruise_v - move.end_v)
/ (move.cruise_v - min_corner_v))
else:
npd = move.end_v * move_extrude_r * self.pressure_advance
extra_decel_d = prev_pressure_d - npd
emcv = move.extrude_max_corner_v
if decel_d and emcv < move.cruise_v:
npd = max(emcv, move.end_v) * pressure_advance
extra_decel_d = prev_pressure_d - npd
if extra_decel_d > 0.:
extra_decel_v = extra_decel_d / decel_t
decel_v -= extra_decel_v

2
klippy/toolhead.py
View File

@ -125,7 +125,7 @@ class MoveQueue:
for move, start_v2, cruise_v2, end_v2 in move_info[:flush_count]:
move.set_junction(start_v2, cruise_v2, end_v2)
# Allow extruder to do its lookahead
flush_count = self.extruder_lookahead(move_info, flush_count, lazy)
flush_count = self.extruder_lookahead(queue, flush_count, lazy)
# Generate step times for all moves ready to be flushed
for move in queue[:flush_count]:
move.move()