shaper_calibrate: Choose input shapers accounting smoothing

Improved algorithm to choose the 'optimal' shaper frequency taking
shaper smoothing into account. This may choose a frequency with
slightly more vibrations but less smoothing. Also allow users to
limit the maximum input shaper smoothing.

Signed-off-by: Dmitry Butyugin <dmbutyugin@google.com>
This commit is contained in:
Dmitry Butyugin 2020-12-19 22:53:50 +01:00 committed by KevinOConnor
parent a637c2f110
commit 1b1a97e8bd
3 changed files with 120 additions and 83 deletions

View File

@ -82,6 +82,7 @@ class ResonanceTester:
('y', config.get('accel_chip_y').strip())]
if self.accel_chip_names[0][1] == self.accel_chip_names[1][1]:
self.accel_chip_names = [('xy', self.accel_chip_names[0][1])]
self.max_smoothing = config.getfloat('max_smoothing', None, minval=0.05)
self.gcode = self.printer.lookup_object('gcode')
self.gcode.register_command("MEASURE_AXES_NOISE",
@ -188,6 +189,9 @@ class ResonanceTester:
else:
calibrate_axes = [axis.lower()]
max_smoothing = gcmd.get_float(
"MAX_SMOOTHING", self.max_smoothing, minval=0.05)
name_suffix = gcmd.get("NAME", time.strftime("%Y%m%d_%H%M%S"))
if not self.is_valid_name_suffix(name_suffix):
raise gcmd.error("Invalid NAME parameter")
@ -244,15 +248,16 @@ class ResonanceTester:
"Calculating the best input shaper parameters for %s axis"
% (axis,))
calibration_data[axis].normalize_to_frequencies()
shaper_name, shaper_freq, shapers_vals = helper.find_best_shaper(
calibration_data[axis], gcmd.respond_info)
best_shaper, all_shapers = helper.find_best_shaper(
calibration_data[axis], max_smoothing, gcmd.respond_info)
gcmd.respond_info(
"Recommended shaper_type_%s = %s, shaper_freq_%s = %.1f Hz"
% (axis, shaper_name, axis, shaper_freq))
helper.save_params(configfile, axis, shaper_name, shaper_freq)
% (axis, best_shaper.name, axis, best_shaper.freq))
helper.save_params(configfile, axis,
best_shaper.name, best_shaper.freq)
csv_name = self.save_calibration_data(
'calibration_data', name_suffix, helper, axis,
calibration_data[axis], shapers_vals)
calibration_data[axis], all_shapers)
gcmd.respond_info(
"Shaper calibration data written to %s file" % (csv_name,))
@ -293,10 +298,10 @@ class ResonanceTester:
return os.path.join("/tmp", name + ".csv")
def save_calibration_data(self, base_name, name_suffix, shaper_calibrate,
axis, calibration_data, shapers_vals=None):
axis, calibration_data, all_shapers=None):
output = self.get_filename(base_name, name_suffix, axis)
shaper_calibrate.save_calibration_data(output, calibration_data,
shapers_vals)
all_shapers)
return output
def load_config(config):

View File

@ -3,7 +3,7 @@
# Copyright (C) 2020 Dmitry Butyugin <dmbutyugin@google.com>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import importlib, logging, math, multiprocessing
import collections, importlib, logging, math, multiprocessing
MIN_FREQ = 5.
MAX_FREQ = 200.
@ -17,11 +17,8 @@ SHAPER_DAMPING_RATIO = 0.1
# Input shapers
######################################################################
class InputShaperCfg:
def __init__(self, name, init_func, min_freq):
self.name = name
self.init_func = init_func
self.min_freq = min_freq
InputShaperCfg = collections.namedtuple(
'InputShaperCfg', ('name', 'init_func', 'min_freq'))
def get_zv_shaper(shaper_freq, damping_ratio):
df = math.sqrt(1. - damping_ratio**2)
@ -100,12 +97,35 @@ def get_3hump_ei_shaper(shaper_freq, damping_ratio):
T = [0., .5*t_d, t_d, 1.5*t_d, 2.*t_d]
return (A, T)
def get_shaper_smoothing(shaper):
# Smoothing calculation params
HALF_ACCEL = 2500.
SCV = 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 max projected smoothing ~= 0.33
INPUT_SHAPERS = [
InputShaperCfg('zv', get_zv_shaper, 15.),
InputShaperCfg('mzv', get_mzv_shaper, 25.),
InputShaperCfg('ei', get_ei_shaper, 30.),
InputShaperCfg('2hump_ei', get_2hump_ei_shaper, 37.5),
InputShaperCfg('3hump_ei', get_3hump_ei_shaper, 50.),
InputShaperCfg('zv', get_zv_shaper, min_freq=22.),
InputShaperCfg('mzv', get_mzv_shaper, min_freq=25.),
InputShaperCfg('ei', get_ei_shaper, min_freq=31.),
InputShaperCfg('2hump_ei', get_2hump_ei_shaper, min_freq=40.),
InputShaperCfg('3hump_ei', get_3hump_ei_shaper, min_freq=50.),
]
######################################################################
@ -142,6 +162,10 @@ class CalibrationData:
psd[self.freq_bins < MIN_FREQ] = 0.
CalibrationResult = collections.namedtuple(
'CalibrationResult',
('name', 'freq', 'vals', 'vibrs', 'smoothing', 'score'))
class ShaperCalibrate:
def __init__(self, printer):
self.printer = printer
@ -283,7 +307,7 @@ class ShaperCalibrate:
remaining_vibrations = (vals * psd).sum() / psd.sum()
return (remaining_vibrations, vals)
def fit_shaper(self, shaper_cfg, calibration_data):
def fit_shaper(self, shaper_cfg, calibration_data, max_smoothing):
np = self.numpy
test_freqs = np.arange(shaper_cfg.min_freq, MAX_SHAPER_FREQ, .2)
@ -292,59 +316,62 @@ class ShaperCalibrate:
psd = calibration_data.psd_sum[freq_bins <= MAX_FREQ]
freq_bins = freq_bins[freq_bins <= MAX_FREQ]
best_freq = None
best_remaining_vibrations = 0
best_shaper_vals = []
best_res = None
results = []
for test_freq in test_freqs[::-1]:
cur_remaining_vibrations = 0.
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)
if max_smoothing and shaper_smoothing > max_smoothing and best_res:
return best_res
# Exact damping ratio of the printer is unknown, pessimizing
# remaining vibrations over possible damping values.
# remaining vibrations over possible damping values
for dr in TEST_DAMPING_RATIOS:
vibrations, vals = self._estimate_remaining_vibrations(
shaper, dr, freq_bins, psd)
shaper_vals = np.maximum(shaper_vals, vals)
if vibrations > cur_remaining_vibrations:
cur_remaining_vibrations = vibrations
if (best_freq is None or
best_remaining_vibrations > cur_remaining_vibrations):
if vibrations > shaper_vibrations:
shaper_vibrations = vibrations
# The score trying to minimize vibrations, but also accounting
# the growth of smoothing. The formula itself does not have any
# special meaning, it simply shows good results on real user data
shaper_score = shaper_vibrations**1.5 * shaper_smoothing
results.append(
CalibrationResult(
name=shaper_cfg.name, freq=test_freq, vals=shaper_vals,
vibrs=shaper_vibrations, smoothing=shaper_smoothing,
score=shaper_score))
if best_res is None or best_res.vibrs > results[-1].vibrs:
# The current frequency is better for the shaper.
best_freq = test_freq
best_remaining_vibrations = cur_remaining_vibrations
best_shaper_vals = shaper_vals
return (best_freq, best_remaining_vibrations, best_shaper_vals)
best_res = results[-1]
# Try to find an 'optimal' shapper configuration: the one that is not
# much worse than the 'best' one, but gives much less smoothing
selected = best_res
for res in results[::-1]:
if res.vibrs < best_res.vibrs * 1.1 and res.score < selected.score:
selected = res
return selected
def find_best_shaper(self, calibration_data, logger=None):
best_shaper = prev_shaper = None
best_freq = prev_freq = 0.
best_vibrations = prev_vibrations = 0.
all_shaper_vals = []
for shaper in INPUT_SHAPERS:
shaper_freq, vibrations, shaper_vals = self.background_process_exec(
self.fit_shaper, (shaper, calibration_data))
def find_best_shaper(self, calibration_data, max_smoothing, logger=None):
best_shaper = None
all_shapers = []
for shaper_cfg in INPUT_SHAPERS:
shaper = self.background_process_exec(self.fit_shaper, (
shaper_cfg, calibration_data, max_smoothing))
if logger is not None:
logger("Fitted shaper '%s' frequency = %.1f Hz "
"(vibrations = %.1f%%)" % (
shaper.name, shaper_freq, vibrations * 100.))
if best_shaper is None or 1.75 * vibrations < best_vibrations:
if 1.25 * vibrations < prev_vibrations:
best_shaper = shaper.name
best_freq = shaper_freq
best_vibrations = vibrations
else:
# The current shaper is good, but not sufficiently better
# than the previous one, using previous shaper instead.
best_shaper = prev_shaper
best_freq = prev_freq
best_vibrations = prev_vibrations
prev_shaper = shaper.name
prev_shaper_vals = shaper_vals
prev_freq = shaper_freq
prev_vibrations = vibrations
all_shaper_vals.append((shaper.name, shaper_freq, shaper_vals))
return (best_shaper, best_freq, all_shaper_vals)
"(vibrations = %.1f%%, smoothing ~= %.3f)" % (
shaper.name, shaper.freq, shaper.vibrs * 100.,
shaper.smoothing))
all_shapers.append(shaper)
if (best_shaper is None or shaper.score * 1.2 < best_shaper.score or
(shaper.score * 1.1 < best_shaper.score and
shaper.smoothing * 1.1 < best_shaper.smoothing)):
# Either the shaper significantly improves the score (by 20%),
# or it improves both the score and smoothing (by 10%)
best_shaper = shaper
return best_shaper, all_shapers
def save_params(self, configfile, axis, shaper_name, shaper_freq):
if axis == 'xy':
@ -355,14 +382,13 @@ class ShaperCalibrate:
configfile.set('input_shaper', 'shaper_freq_'+axis,
'%.1f' % (shaper_freq,))
def save_calibration_data(self, output, calibration_data,
shapers_vals=None):
def save_calibration_data(self, output, calibration_data, shapers=None):
try:
with open(output, "w") as csvfile:
csvfile.write("freq,psd_x,psd_y,psd_z,psd_xyz")
if shapers_vals:
for name, freq, _ in shapers_vals:
csvfile.write(",%s(%.1f)" % (name, freq))
if shapers:
for shaper in shapers:
csvfile.write(",%s(%.1f)" % (shaper.name, shaper.freq))
csvfile.write("\n")
num_freqs = calibration_data.freq_bins.shape[0]
for i in range(num_freqs):
@ -374,9 +400,9 @@ class ShaperCalibrate:
calibration_data.psd_y[i],
calibration_data.psd_z[i],
calibration_data.psd_sum[i]))
if shapers_vals:
for _, _, vals in shapers_vals:
csvfile.write(",%.3f" % (vals[i],))
if shapers:
for shaper in shapers:
csvfile.write(",%.3f" % (shaper.vals[i],))
csvfile.write("\n")
except IOError as e:
raise self.error("Error writing to file '%s': %s", output, str(e))

View File

@ -40,7 +40,7 @@ def parse_log(logname):
######################################################################
# Find the best shaper parameters
def calibrate_shaper(datas, csv_output):
def calibrate_shaper(datas, csv_output, max_smoothing):
helper = ShaperCalibrate(printer=None)
if isinstance(datas[0], CalibrationData):
calibration_data = datas[0]
@ -52,19 +52,19 @@ def calibrate_shaper(datas, csv_output):
for data in datas[1:]:
calibration_data.join(helper.process_accelerometer_data(data))
calibration_data.normalize_to_frequencies()
shaper_name, shaper_freq, shapers_vals = helper.find_best_shaper(
calibration_data, print)
print("Recommended shaper is %s @ %.1f Hz" % (shaper_name, shaper_freq))
shaper, all_shapers = helper.find_best_shaper(
calibration_data, max_smoothing, print)
print("Recommended shaper is %s @ %.1f Hz" % (shaper.name, shaper.freq))
if csv_output is not None:
helper.save_calibration_data(
csv_output, calibration_data, shapers_vals)
return shaper_name, shapers_vals, calibration_data
csv_output, calibration_data, all_shapers)
return shaper.name, all_shapers, calibration_data
######################################################################
# Plot frequency response and suggested input shapers
######################################################################
def plot_freq_response(lognames, calibration_data, shapers_vals,
def plot_freq_response(lognames, calibration_data, shapers,
selected_shaper, max_freq):
freqs = calibration_data.freq_bins
psd = calibration_data.psd_sum[freqs <= max_freq]
@ -99,13 +99,15 @@ def plot_freq_response(lognames, calibration_data, shapers_vals,
ax2 = ax.twinx()
ax2.set_ylabel('Shaper vibration reduction (ratio)')
best_shaper_vals = None
for name, freq, vals in shapers_vals:
label = "%s (%.1f Hz)" % (name.upper(), freq)
for shaper in shapers:
label = "%s (%.1f Hz, vibr=%.1f%%, sm~=%.2f)" % (
shaper.name.upper(), shaper.freq,
shaper.vibrs * 100., shaper.smoothing)
linestyle = 'dotted'
if name == selected_shaper:
if shaper.name == selected_shaper:
linestyle = 'dashdot'
best_shaper_vals = vals
ax2.plot(freqs, vals, label=label, linestyle=linestyle)
best_shaper_vals = shaper.vals
ax2.plot(freqs, shaper.vals, label=label, linestyle=linestyle)
ax.plot(freqs, psd * best_shaper_vals,
label='After\nshaper', color='cyan')
# A hack to add a human-readable shaper recommendation to legend
@ -140,22 +142,26 @@ def main():
default=None, help="filename of output csv file")
opts.add_option("-f", "--max_freq", type="float", default=200.,
help="maximum frequency to graph")
opts.add_option("-s", "--max_smoothing", type="float", default=None,
help="maximum shaper smoothing to allow")
options, args = opts.parse_args()
if len(args) < 1:
opts.error("Incorrect number of arguments")
if options.max_smoothing is not None and options.max_smoothing < 0.05:
opts.error("Too small max_smoothing specified (must be at least 0.05)")
# Parse data
datas = [parse_log(fn) for fn in args]
# Calibrate shaper and generate outputs
selected_shaper, shapers_vals, calibration_data = calibrate_shaper(
datas, options.csv)
selected_shaper, shapers, calibration_data = calibrate_shaper(
datas, options.csv, options.max_smoothing)
if not options.csv or options.output:
# Draw graph
setup_matplotlib(options.output is not None)
fig = plot_freq_response(args, calibration_data, shapers_vals,
fig = plot_freq_response(args, calibration_data, shapers,
selected_shaper, options.max_freq)
# Show graph