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| author | Kevin O'Connor <kevin@koconnor.net> | 2016-11-04 21:11:14 -0400 |
|---|---|---|
| committer | Kevin O'Connor <kevin@koconnor.net> | 2016-11-05 11:06:58 -0400 |
| commit | 93dd310add46272f02b18ddd7f9b2f553d6e7ee0 (patch) | |
| tree | 695aed3c7321680b6c47d399fd924114c8f4f9ac /klippy/extruder.py | |
| parent | a201385008de76c5e52ec40fc63e6b292863e71c (diff) | |
| download | kutter-93dd310add46272f02b18ddd7f9b2f553d6e7ee0.tar.gz kutter-93dd310add46272f02b18ddd7f9b2f553d6e7ee0.tar.xz kutter-93dd310add46272f02b18ddd7f9b2f553d6e7ee0.zip | |
extruder: Don't assume start_v matches last end_v in pressure advance
Due to minor differences in the extrude ratio, the last end velocity
of the filament may not exactly match the next move's start velocity
of the filament. Implement more precise calculations for pressure
advance to take this into account.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Diffstat (limited to 'klippy/extruder.py')
| -rw-r--r-- | klippy/extruder.py | 53 |
1 files changed, 30 insertions, 23 deletions
diff --git a/klippy/extruder.py b/klippy/extruder.py index ad439421..4abbb7dd 100644 --- a/klippy/extruder.py +++ b/klippy/extruder.py @@ -44,38 +44,45 @@ class PrinterExtruder: decel_v = cruise_v # Update for pressure advance + start_pos = self.extrude_pos 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 - extra_accel_d = (cruise_v - start_v) * self.pressure_advance - accel_d += extra_accel_d + move_extrude_r = move.extrude_r + prev_pressure_d = start_pos - move.start_pos[3] if accel_t: - start_v += extra_accel_d / accel_t + npd = move.cruise_v * move_extrude_r * self.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: - extra_decel_d = (cruise_v - end_v) * self.pressure_advance - extra_decel_v = extra_decel_d / decel_t - decel_v -= extra_decel_v - end_v -= extra_decel_v - if decel_v <= 0.: - # The entire decel phase is replaced with retraction - retract_t = decel_t - retract_d = -(end_v + decel_v) * 0.5 * decel_t - retract_v = -decel_v - decel_t = decel_d = 0. - elif end_v < 0.: - # Split decel phase into decel and retraction - retract_t = -end_v * inv_accel - retract_d = -end_v * 0.5 * retract_t - decel_t -= retract_t - decel_d = decel_v * 0.5 * decel_t - else: - # There is still only a decel phase (no retraction) - decel_d -= extra_decel_d + npd = move.end_v * move_extrude_r * self.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 + end_v -= extra_decel_v + if decel_v <= 0.: + # The entire decel phase is replaced with retraction + retract_t = decel_t + retract_d = -(end_v + decel_v) * 0.5 * decel_t + retract_v = -decel_v + decel_t = decel_d = 0. + elif end_v < 0.: + # Split decel phase into decel and retraction + retract_t = -end_v * inv_accel + retract_d = -end_v * 0.5 * retract_t + decel_t -= retract_t + decel_d = decel_v * 0.5 * decel_t + else: + # There is still only a decel phase (no retraction) + decel_d -= extra_decel_d # Determine regular steps forward_d = accel_d + cruise_d + decel_d - start_pos = self.extrude_pos end_pos = start_pos + forward_d inv_step_dist = self.stepper.inv_step_dist new_step_pos = int(end_pos*inv_step_dist + 0.5) |