input_shaper: Define input shapers in a single place in Python code

Signed-off-by: Dmitry Butyugin <dmbutyugin@google.com>
This commit is contained in:
Dmitry Butyugin 2021-10-22 20:46:20 +02:00 committed by KevinOConnor
parent 6c395fd016
commit d5a7a7f00f
7 changed files with 209 additions and 385 deletions

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@ -4,128 +4,16 @@
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import collections, importlib, logging, math, multiprocessing
shaper_defs = importlib.import_module('.shaper_defs', 'extras')
MIN_FREQ = 5.
MAX_FREQ = 200.
WINDOW_T_SEC = 0.5
MAX_SHAPER_FREQ = 150.
SHAPER_VIBRATION_REDUCTION=20.
TEST_DAMPING_RATIOS=[0.075, 0.1, 0.15]
SHAPER_DAMPING_RATIO = 0.1
######################################################################
# Input shapers
######################################################################
InputShaperCfg = collections.namedtuple(
'InputShaperCfg', ('name', 'init_func', 'min_freq'))
def get_zv_shaper(shaper_freq, damping_ratio):
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
A = [1., K]
T = [0., .5*t_d]
return (A, T)
def get_zvd_shaper(shaper_freq, damping_ratio):
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
A = [1., 2.*K, K**2]
T = [0., .5*t_d, t_d]
return (A, T)
def get_mzv_shaper(shaper_freq, damping_ratio):
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-.75 * damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
a1 = 1. - 1. / math.sqrt(2.)
a2 = (math.sqrt(2.) - 1.) * K
a3 = a1 * K * K
A = [a1, a2, a3]
T = [0., .375*t_d, .75*t_d]
return (A, T)
def get_ei_shaper(shaper_freq, damping_ratio):
v_tol = 1. / SHAPER_VIBRATION_REDUCTION # vibration tolerance
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
a1 = .25 * (1. + v_tol)
a2 = .5 * (1. - v_tol) * K
a3 = a1 * K * K
A = [a1, a2, a3]
T = [0., .5*t_d, t_d]
return (A, T)
def get_2hump_ei_shaper(shaper_freq, damping_ratio):
v_tol = 1. / SHAPER_VIBRATION_REDUCTION # vibration tolerance
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
V2 = v_tol**2
X = pow(V2 * (math.sqrt(1. - V2) + 1.), 1./3.)
a1 = (3.*X*X + 2.*X + 3.*V2) / (16.*X)
a2 = (.5 - a1) * K
a3 = a2 * K
a4 = a1 * K * K * K
A = [a1, a2, a3, a4]
T = [0., .5*t_d, t_d, 1.5*t_d]
return (A, T)
def get_3hump_ei_shaper(shaper_freq, damping_ratio):
v_tol = 1. / SHAPER_VIBRATION_REDUCTION # vibration tolerance
df = math.sqrt(1. - damping_ratio**2)
K = math.exp(-damping_ratio * math.pi / df)
t_d = 1. / (shaper_freq * df)
K2 = K*K
a1 = 0.0625 * (1. + 3. * v_tol + 2. * math.sqrt(2. * (v_tol + 1.) * v_tol))
a2 = 0.25 * (1. - v_tol) * K
a3 = (0.5 * (1. + v_tol) - 2. * a1) * K2
a4 = a2 * K2
a5 = a1 * K2 * K2
A = [a1, a2, a3, a4, a5]
T = [0., .5*t_d, t_d, 1.5*t_d, 2.*t_d]
return (A, T)
def get_shaper_smoothing(shaper, accel=5000, scv=5.):
half_accel = accel * .5
A, T = shaper
inv_D = 1. / sum(A)
n = len(T)
# Calculate input shaper shift
ts = sum([A[i] * T[i] for i in range(n)]) * inv_D
# Calculate offset for 90 and 180 degrees turn
offset_90 = offset_180 = 0.
for i in range(n):
if T[i] >= ts:
# Calculate offset for one of the axes
offset_90 += A[i] * (scv + half_accel * (T[i]-ts)) * (T[i]-ts)
offset_180 += A[i] * half_accel * (T[i]-ts)**2
offset_90 *= inv_D * math.sqrt(2.)
offset_180 *= inv_D
return max(offset_90, offset_180)
# min_freq for each shaper is chosen to have projected max_accel ~= 1500
INPUT_SHAPERS = [
InputShaperCfg('zv', get_zv_shaper, min_freq=21.),
InputShaperCfg('mzv', get_mzv_shaper, min_freq=23.),
InputShaperCfg('ei', get_ei_shaper, min_freq=29.),
InputShaperCfg('2hump_ei', get_2hump_ei_shaper, min_freq=39.),
InputShaperCfg('3hump_ei', get_3hump_ei_shaper, min_freq=48.),
]
AUTOTUNE_SHAPERS = ['zv', 'mzv', 'ei', '2hump_ei', '3hump_ei']
######################################################################
# Frequency response calculation and shaper auto-tuning
@ -313,12 +201,32 @@ class ShaperCalibrate:
# The input shaper can only reduce the amplitude of vibrations by
# SHAPER_VIBRATION_REDUCTION times, so all vibrations below that
# threshold can be igonred
vibrations_threshold = psd.max() / SHAPER_VIBRATION_REDUCTION
vibr_threshold = psd.max() / shaper_defs.SHAPER_VIBRATION_REDUCTION
remaining_vibrations = self.numpy.maximum(
vals * psd - vibrations_threshold, 0).sum()
all_vibrations = self.numpy.maximum(psd - vibrations_threshold, 0).sum()
vals * psd - vibr_threshold, 0).sum()
all_vibrations = self.numpy.maximum(psd - vibr_threshold, 0).sum()
return (remaining_vibrations / all_vibrations, vals)
def _get_shaper_smoothing(self, shaper, accel=5000, scv=5.):
half_accel = accel * .5
A, T = shaper
inv_D = 1. / sum(A)
n = len(T)
# Calculate input shaper shift
ts = sum([A[i] * T[i] for i in range(n)]) * inv_D
# Calculate offset for 90 and 180 degrees turn
offset_90 = offset_180 = 0.
for i in range(n):
if T[i] >= ts:
# Calculate offset for one of the axes
offset_90 += A[i] * (scv + half_accel * (T[i]-ts)) * (T[i]-ts)
offset_180 += A[i] * half_accel * (T[i]-ts)**2
offset_90 *= inv_D * math.sqrt(2.)
offset_180 *= inv_D
return max(offset_90, offset_180)
def fit_shaper(self, shaper_cfg, calibration_data, max_smoothing):
np = self.numpy
@ -333,8 +241,9 @@ class ShaperCalibrate:
for test_freq in test_freqs[::-1]:
shaper_vibrations = 0.
shaper_vals = np.zeros(shape=freq_bins.shape)
shaper = shaper_cfg.init_func(test_freq, SHAPER_DAMPING_RATIO)
shaper_smoothing = get_shaper_smoothing(shaper)
shaper = shaper_cfg.init_func(
test_freq, shaper_defs.DEFAULT_DAMPING_RATIO)
shaper_smoothing = self._get_shaper_smoothing(shaper)
if max_smoothing and shaper_smoothing > max_smoothing and best_res:
return best_res
# Exact damping ratio of the printer is unknown, pessimizing
@ -387,14 +296,16 @@ class ShaperCalibrate:
# Just some empirically chosen value which produces good projections
# for max_accel without much smoothing
TARGET_SMOOTHING = 0.12
max_accel = self._bisect(lambda test_accel: get_shaper_smoothing(
max_accel = self._bisect(lambda test_accel: self._get_shaper_smoothing(
shaper, test_accel) <= TARGET_SMOOTHING)
return max_accel
def find_best_shaper(self, calibration_data, max_smoothing, logger=None):
best_shaper = None
all_shapers = []
for shaper_cfg in INPUT_SHAPERS:
for shaper_cfg in shaper_defs.INPUT_SHAPERS:
if shaper_cfg.name not in AUTOTUNE_SHAPERS:
continue
shaper = self.background_process_exec(self.fit_shaper, (
shaper_cfg, calibration_data, max_smoothing))
if logger is not None: