cross-belt comparison plot

This commit is contained in:
Félix Boisselier
2024-05-03 20:08:17 +02:00
parent ab5600804f
commit 17b7e1a2d2
2 changed files with 185 additions and 221 deletions

View File

@@ -16,26 +16,17 @@ import matplotlib.font_manager
import matplotlib.pyplot as plt
import matplotlib.ticker
import numpy as np
from scipy.interpolate import griddata
matplotlib.use('Agg')
from ..helpers.common_func import (
compute_curve_similarity_factor,
compute_spectrogram,
detect_peaks,
parse_log,
setup_klipper_import,
)
from ..helpers.common_func import detect_peaks, parse_log, setup_klipper_import
from ..helpers.locale_utils import print_with_c_locale, set_locale
ALPHABET = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' # For paired peaks names
PEAKS_DETECTION_THRESHOLD = 0.20
CURVE_SIMILARITY_SIGMOID_K = 0.6
DC_GRAIN_OF_SALT_FACTOR = 0.75
DC_THRESHOLD_METRIC = 1.5e9
DC_MAX_UNPAIRED_PEAKS_ALLOWED = 4
PEAKS_DETECTION_THRESHOLD = 0.20 # Threshold to detect peaks in the PSD signal
DC_MAX_PEAKS = 2 # Maximum ideal number of peaks
DC_MAX_UNPAIRED_PEAKS_ALLOWED = 0 # No unpaired peaks are tolerated
# Define the SignalData namedtuple
SignalData = namedtuple('CalibrationData', ['freqs', 'psd', 'peaks', 'paired_peaks', 'unpaired_peaks'])
@@ -103,78 +94,40 @@ def pair_peaks(peaks1, freqs1, psd1, peaks2, freqs2, psd2):
######################################################################
# Interpolate source_data (2D) to match target_x and target_y in order to
# get similar time and frequency dimensions for the differential spectrogram
def interpolate_2d(target_x, target_y, source_x, source_y, source_data):
# Create a grid of points in the source and target space
source_points = np.array([(x, y) for y in source_y for x in source_x])
target_points = np.array([(x, y) for y in target_y for x in target_x])
def compute_mhi(similarity_coefficient, total_num_peaks, num_unpaired_peaks):
# Start with the similarity coefficient directly scaled to a percentage
base_percentage = similarity_coefficient
# Flatten the source data to match the flattened source points
source_values = source_data.flatten()
# Bonus for ideal number of total peaks (1 or 2)
if total_num_peaks <= DC_MAX_PEAKS:
peak_bonus = 1.1 # Boost by 10% if the number of peaks is ideal
else:
peak_bonus = DC_MAX_PEAKS / total_num_peaks # Reduce MHI if more than ideal number of peaks
# Interpolate and reshape the interpolated data to match the target grid shape and replace NaN with zeros
interpolated_data = griddata(source_points, source_values, target_points, method='nearest')
interpolated_data = interpolated_data.reshape((len(target_y), len(target_x)))
interpolated_data = np.nan_to_num(interpolated_data)
adjusted_percentage = base_percentage * peak_bonus
return interpolated_data
# Main logic function to combine two similar spectrogram - ie. from both belts paths - by substracting signals in order to create
# a new composite spectrogram. This result of a divergent but mostly centered new spectrogram (center will be white) with some colored zones
# highlighting differences in the belts paths. The summative spectrogram is used for the MHI calculation.
def compute_combined_spectrogram(data1, data2):
pdata1, bins1, t1 = compute_spectrogram(data1)
pdata2, bins2, t2 = compute_spectrogram(data2)
# Interpolate the spectrograms
pdata2_interpolated = interpolate_2d(bins1, t1, bins2, t2, pdata2)
# Combine them in two form: a summed diff for the MHI computation and a diverging diff for the spectrogram colors
combined_sum = np.abs(pdata1 - pdata2_interpolated)
combined_divergent = pdata1 - pdata2_interpolated
return combined_sum, combined_divergent, bins1, t1
# Compute a composite and highly subjective value indicating the "mechanical health of the printer (0 to 100%)" that represent the
# likelihood of mechanical issues on the printer. It is based on the differential spectrogram sum of gradient, salted with a bit
# of the estimated similarity cross-correlation from compute_curve_similarity_factor() and with a bit of the number of unpaired peaks.
# This result in a percentage value quantifying the machine behavior around the main resonances that give an hint if only touching belt tension
# will give good graphs or if there is a chance of mechanical issues in the background (above 50% should be considered as probably problematic)
def compute_mhi(combined_data, similarity_coefficient, num_unpaired_peaks):
# filtered_data = combined_data[combined_data > 100]
filtered_data = np.abs(combined_data)
# First compute a "total variability metric" based on the sum of the gradient that sum the magnitude of will emphasize regions of the
# spectrogram where there are rapid changes in magnitude (like the edges of resonance peaks).
total_variability_metric = np.sum(np.abs(np.gradient(filtered_data)))
# Scale the metric to a percentage using the threshold (found empirically on a large number of user data shared to me)
base_percentage = (np.log1p(total_variability_metric) / np.log1p(DC_THRESHOLD_METRIC)) * 100
# Adjust the percentage based on the similarity_coefficient to add a grain of salt
adjusted_percentage = base_percentage * (1 - DC_GRAIN_OF_SALT_FACTOR * (similarity_coefficient / 100))
# Adjust the percentage again based on the number of unpaired peaks to add a second grain of salt
peak_confidence = num_unpaired_peaks / DC_MAX_UNPAIRED_PEAKS_ALLOWED
final_percentage = (1 - peak_confidence) * adjusted_percentage + peak_confidence * 100
# Heavy penalty for unpaired peaks
if num_unpaired_peaks > DC_MAX_UNPAIRED_PEAKS_ALLOWED:
unpaired_peak_penalty = num_unpaired_peaks * 5 # Applying a strong penalty factor for each unpaired peak
final_percentage = adjusted_percentage - unpaired_peak_penalty
else:
final_percentage = adjusted_percentage
# Ensure the result lies between 0 and 100 by clipping the computed value
final_percentage = np.clip(final_percentage, 0, 100)
return final_percentage, mhi_lut(final_percentage)
return mhi_lut(final_percentage)
# LUT to transform the MHI into a textual value easy to understand for the users of the script
def mhi_lut(mhi):
ranges = [
(0, 30, 'Excellent mechanical health'),
(30, 45, 'Good mechanical health'),
(70, 100, 'Excellent mechanical health'),
(55, 70, 'Good mechanical health'),
(45, 55, 'Acceptable mechanical health'),
(55, 70, 'Potential signs of a mechanical issue'),
(70, 85, 'Likely a mechanical issue'),
(85, 100, 'Mechanical issue detected'),
(30, 45, 'Potential signs of a mechanical issue'),
(15, 30, 'Likely a mechanical issue'),
(0, 15, 'Mechanical issue detected'),
]
for lower, upper, message in ranges:
if lower < mhi <= upper:
@@ -188,22 +141,7 @@ def mhi_lut(mhi):
######################################################################
def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, max_freq):
# Get the belt name for the legend to avoid putting the full file name
signal1_belt = (lognames[0].split('/')[-1]).split('_')[-1][0]
signal2_belt = (lognames[1].split('/')[-1]).split('_')[-1][0]
if signal1_belt == 'A' and signal2_belt == 'B':
signal1_belt += ' (axis 1,-1)'
signal2_belt += ' (axis 1, 1)'
elif signal1_belt == 'B' and signal2_belt == 'A':
signal1_belt += ' (axis 1, 1)'
signal2_belt += ' (axis 1,-1)'
else:
print_with_c_locale(
"Warning: belts doesn't seem to have the correct name A and B (extracted from the filename.csv)"
)
def plot_compare_frequency(ax, signal1, signal2, signal1_belt, signal2_belt, max_freq):
# Plot the two belts PSD signals
ax.plot(signal1.freqs, signal1.psd, label='Belt ' + signal1_belt, color=KLIPPAIN_COLORS['purple'])
ax.plot(signal2.freqs, signal2.psd, label='Belt ' + signal2_belt, color=KLIPPAIN_COLORS['orange'])
@@ -287,7 +225,6 @@ def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, ma
# Add estimated similarity to the graph
ax2 = ax.twinx() # To split the legends in two box
ax2.yaxis.set_visible(False)
ax2.plot([], [], ' ', label=f'Estimated similarity: {similarity_factor:.1f}%')
ax2.plot([], [], ' ', label=f'Number of unpaired peaks: {unpaired_peak_count}')
# Setting axis parameters, grid and graph title
@@ -295,7 +232,7 @@ def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, ma
ax.set_xlim([0, max_freq])
ax.set_ylabel('Power spectral density')
psd_highest_max = max(signal1.psd.max(), signal2.psd.max())
ax.set_ylim([0, psd_highest_max + psd_highest_max * 0.05])
ax.set_ylim([0, psd_highest_max * 1.1])
ax.xaxis.set_minor_locator(matplotlib.ticker.AutoMinorLocator())
ax.yaxis.set_minor_locator(matplotlib.ticker.AutoMinorLocator())
@@ -305,7 +242,7 @@ def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, ma
fontP = matplotlib.font_manager.FontProperties()
fontP.set_size('small')
ax.set_title(
'Belts Frequency Profiles (estimated similarity: {:.1f}%)'.format(similarity_factor),
'Belts frequency profiles',
fontsize=14,
color=KLIPPAIN_COLORS['dark_orange'],
weight='bold',
@@ -321,7 +258,7 @@ def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, ma
offset_table = ax.table(
cellText=offsets_table_data,
colLabels=columns,
bbox=[0.66, 0.75, 0.33, 0.15],
bbox=[0.66, 0.79, 0.33, 0.15],
loc='upper right',
cellLoc='center',
)
@@ -340,91 +277,126 @@ def plot_compare_frequency(ax, lognames, signal1, signal2, similarity_factor, ma
return
def plot_difference_spectrogram(ax, signal1, signal2, t, bins, combined_divergent, textual_mhi, max_freq):
ax.set_title('Differential Spectrogram', fontsize=14, color=KLIPPAIN_COLORS['dark_orange'], weight='bold')
ax.plot([], [], ' ', label=f'{textual_mhi} (experimental)')
# Compute quantile-quantile plot to compare the two belts
def plot_versus_belts(ax, common_freqs, signal1, signal2, interp_psd1, interp_psd2, signal1_belt, signal2_belt):
ax.set_title('Cross-belts comparison plot', fontsize=14, color=KLIPPAIN_COLORS['dark_orange'], weight='bold')
# Draw the differential spectrogram with a specific custom norm to get orange or purple values where there is signal or white near zeros
# imgshow is better suited here than pcolormesh since its result is already rasterized and we doesn't need to keep vector graphics
# when saving to a final .png file. Using it also allow to save ~150-200MB of RAM during the "fig.savefig" operation.
colors = [
KLIPPAIN_COLORS['dark_orange'],
KLIPPAIN_COLORS['orange'],
'white',
KLIPPAIN_COLORS['purple'],
KLIPPAIN_COLORS['dark_purple'],
]
cm = matplotlib.colors.LinearSegmentedColormap.from_list(
'klippain_divergent', list(zip([0, 0.25, 0.5, 0.75, 1], colors))
)
norm = matplotlib.colors.TwoSlopeNorm(vmin=np.min(combined_divergent), vcenter=0, vmax=np.max(combined_divergent))
ax.imshow(
combined_divergent.T,
cmap=cm,
norm=norm,
aspect='auto',
extent=[t[0], t[-1], bins[0], bins[-1]],
interpolation='bilinear',
origin='lower',
max_psd = max(np.max(interp_psd1), np.max(interp_psd2))
ideal_line = np.linspace(0, max_psd * 1.1, 500)
green_boundary = ideal_line + (0.35 * max_psd * np.exp(-ideal_line / (0.6 * max_psd)))
ax.fill_betweenx(ideal_line, ideal_line, green_boundary, color='green', alpha=0.15)
ax.fill_between(ideal_line, ideal_line, green_boundary, color='green', alpha=0.15, label='Good zone')
ax.plot(
ideal_line,
ideal_line,
'--',
label='Ideal line',
color='red',
linewidth=2,
)
ax.set_xlabel('Frequency (hz)')
ax.set_xlim([0.0, max_freq])
ax.set_ylabel('Time (s)')
ax.set_ylim([0, bins[-1]])
ax.plot(interp_psd1, interp_psd2, color='dimgrey', marker='o', markersize=1.5)
# ax.fill_betweenx(interp_psd2, interp_psd1, color='grey', alpha=0.2)
paired_peak_count = 0
unpaired_peak_count = 0
for _, (peak1, peak2) in enumerate(signal1.paired_peaks):
label = ALPHABET[paired_peak_count]
freq1 = signal1.freqs[peak1[0]]
freq2 = signal2.freqs[peak2[0]]
nearest_idx1 = np.argmin(np.abs(common_freqs - freq1))
nearest_idx2 = np.argmin(np.abs(common_freqs - freq2))
if nearest_idx1 == nearest_idx2:
psd1_peak_value = interp_psd1[nearest_idx1]
psd2_peak_value = interp_psd2[nearest_idx1]
ax.plot(psd1_peak_value, psd2_peak_value, marker='o', color='black', markersize=7)
ax.annotate(
f'{label}1/{label}2',
(psd1_peak_value, psd2_peak_value),
textcoords='offset points',
xytext=(-7, 7),
fontsize=13,
color='black',
)
else:
psd1_peak_value = interp_psd1[nearest_idx1]
psd1_on_peak = interp_psd1[nearest_idx2]
psd2_peak_value = interp_psd2[nearest_idx2]
psd2_on_peak = interp_psd2[nearest_idx1]
ax.plot(psd1_on_peak, psd2_peak_value, marker='o', color=KLIPPAIN_COLORS['orange'], markersize=7)
ax.plot(psd1_peak_value, psd2_on_peak, marker='o', color=KLIPPAIN_COLORS['purple'], markersize=7)
ax.annotate(
f'{label}1',
(psd1_peak_value, psd2_on_peak),
textcoords='offset points',
xytext=(0, 7),
fontsize=13,
color='black',
)
ax.annotate(
f'{label}2',
(psd1_on_peak, psd2_peak_value),
textcoords='offset points',
xytext=(0, 7),
fontsize=13,
color='black',
)
paired_peak_count += 1
for _, peak_index in enumerate(signal1.unpaired_peaks):
freq1 = signal1.freqs[peak_index]
freq2 = signal2.freqs[peak_index]
nearest_idx1 = np.argmin(np.abs(common_freqs - freq1))
nearest_idx2 = np.argmin(np.abs(common_freqs - freq2))
psd1_peak_value = interp_psd1[nearest_idx1]
psd2_peak_value = interp_psd2[nearest_idx1]
ax.plot(psd1_peak_value, psd2_peak_value, marker='o', color=KLIPPAIN_COLORS['purple'], markersize=7)
ax.annotate(
str(unpaired_peak_count + 1),
(psd1_peak_value, psd2_peak_value),
textcoords='offset points',
fontsize=13,
weight='bold',
color=KLIPPAIN_COLORS['red_pink'],
xytext=(0, 7),
)
unpaired_peak_count += 1
for _, peak_index in enumerate(signal2.unpaired_peaks):
freq1 = signal1.freqs[peak_index]
freq2 = signal2.freqs[peak_index]
nearest_idx1 = np.argmin(np.abs(common_freqs - freq1))
nearest_idx2 = np.argmin(np.abs(common_freqs - freq2))
psd1_peak_value = interp_psd1[nearest_idx1]
psd2_peak_value = interp_psd2[nearest_idx1]
ax.plot(psd1_peak_value, psd2_peak_value, marker='o', color=KLIPPAIN_COLORS['orange'], markersize=7)
ax.annotate(
str(unpaired_peak_count + 1),
(psd1_peak_value, psd2_peak_value),
textcoords='offset points',
fontsize=13,
weight='bold',
color=KLIPPAIN_COLORS['red_pink'],
xytext=(0, 7),
)
unpaired_peak_count += 1
ax.set_xlabel(f'Belt {signal1_belt}')
ax.set_ylabel(f'Belt {signal2_belt}')
ax.set_xlim([0, max_psd * 1.1])
ax.set_ylim([0, max_psd * 1.1])
ax.xaxis.set_minor_locator(matplotlib.ticker.AutoMinorLocator())
ax.yaxis.set_minor_locator(matplotlib.ticker.AutoMinorLocator())
ax.ticklabel_format(axis='y', style='scientific', scilimits=(0, 0))
ax.grid(which='major', color='grey')
ax.grid(which='minor', color='lightgrey')
fontP = matplotlib.font_manager.FontProperties()
fontP.set_size('medium')
ax.legend(loc='best', prop=fontP)
# Plot vertical lines for unpaired peaks
unpaired_peak_count = 0
for _, peak in enumerate(signal1.unpaired_peaks):
ax.axvline(signal1.freqs[peak], color=KLIPPAIN_COLORS['red_pink'], linestyle='dotted', linewidth=1.5)
ax.annotate(
f'Peak {unpaired_peak_count + 1}',
(signal1.freqs[peak], t[-1] * 0.05),
textcoords='data',
color=KLIPPAIN_COLORS['red_pink'],
rotation=90,
fontsize=10,
verticalalignment='bottom',
horizontalalignment='right',
)
unpaired_peak_count += 1
for _, peak in enumerate(signal2.unpaired_peaks):
ax.axvline(signal2.freqs[peak], color=KLIPPAIN_COLORS['red_pink'], linestyle='dotted', linewidth=1.5)
ax.annotate(
f'Peak {unpaired_peak_count + 1}',
(signal2.freqs[peak], t[-1] * 0.05),
textcoords='data',
color=KLIPPAIN_COLORS['red_pink'],
rotation=90,
fontsize=10,
verticalalignment='bottom',
horizontalalignment='right',
)
unpaired_peak_count += 1
# Plot vertical lines and zones for paired peaks
for idx, (peak1, peak2) in enumerate(signal1.paired_peaks):
label = ALPHABET[idx]
x_min = min(peak1[1], peak2[1])
x_max = max(peak1[1], peak2[1])
ax.axvline(x_min, color=KLIPPAIN_COLORS['dark_purple'], linestyle='dotted', linewidth=1.5)
ax.axvline(x_max, color=KLIPPAIN_COLORS['dark_purple'], linestyle='dotted', linewidth=1.5)
ax.fill_between([x_min, x_max], 0, np.max(combined_divergent), color=KLIPPAIN_COLORS['dark_purple'], alpha=0.3)
ax.annotate(
f'Peaks {label}',
(x_min, t[-1] * 0.05),
textcoords='data',
color=KLIPPAIN_COLORS['dark_purple'],
rotation=90,
fontsize=10,
verticalalignment='bottom',
horizontalalignment='right',
)
ax.legend(loc='upper left', prop=fontP)
return
@@ -462,10 +434,16 @@ def belts_calibration(lognames, klipperdir='~/klipper', max_freq=200.0, st_versi
if len(datas) > 2:
raise ValueError('Incorrect number of .csv files used (this function needs exactly two files to compare them)!')
# Get the belts name for the legend to avoid putting the full file name
belt_info = {'A': ' (axis 1,-1)', 'B': ' (axis 1, 1)'}
signal1_belt = (lognames[0].split('/')[-1]).split('_')[-1][0]
signal2_belt = (lognames[1].split('/')[-1]).split('_')[-1][0]
signal1_belt += belt_info.get(signal1_belt, '')
signal2_belt += belt_info.get(signal2_belt, '')
# Compute calibration data for the two datasets with automatic peaks detection
signal1 = compute_signal_data(datas[0], max_freq)
signal2 = compute_signal_data(datas[1], max_freq)
combined_sum, combined_divergent, bins, t = compute_combined_spectrogram(datas[0], datas[1])
del datas
# Pair the peaks across the two datasets
@@ -475,38 +453,41 @@ def belts_calibration(lognames, klipperdir='~/klipper', max_freq=200.0, st_versi
signal1 = signal1._replace(paired_peaks=paired_peaks, unpaired_peaks=unpaired_peaks1)
signal2 = signal2._replace(paired_peaks=paired_peaks, unpaired_peaks=unpaired_peaks2)
# Compute the similarity (using cross-correlation of the PSD signals)
similarity_factor = compute_curve_similarity_factor(
signal1.freqs, signal1.psd, signal2.freqs, signal2.psd, CURVE_SIMILARITY_SIGMOID_K
)
print_with_c_locale(f'Belts estimated similarity: {similarity_factor:.1f}%')
# Compute the MHI value from the differential spectrogram sum of gradient, salted with the similarity factor and the number of
# unpaired peaks from the belts frequency profile. Be careful, this value is highly opinionated and is pretty experimental!
mhi, textual_mhi = compute_mhi(
combined_sum, similarity_factor, len(signal1.unpaired_peaks) + len(signal2.unpaired_peaks)
)
print_with_c_locale(f'[experimental] Mechanical Health Indicator: {textual_mhi.lower()} ({mhi:.1f}%)')
# Re-interpolate the PSD signals to a common frequency range to be able to plot them one against the other point by point
common_freqs = np.linspace(0, max_freq, 500)
interp_psd1 = np.interp(common_freqs, signal1.freqs, signal1.psd)
interp_psd2 = np.interp(common_freqs, signal2.freqs, signal2.psd)
# Create graph layout
fig, (ax1, ax2) = plt.subplots(
2,
# Calculating R^2 to y=x line to compute the similarity between the two belts
ss_res = np.sum((interp_psd2 - interp_psd1) ** 2)
ss_tot = np.sum((interp_psd2 - np.mean(interp_psd2)) ** 2)
similarity_factor = (1 - (ss_res / ss_tot)) * 100
print_with_c_locale(f'Belts estimated similarity: {similarity_factor:.1f}%')
num_unpaired_peaks = len(unpaired_peaks1) + len(unpaired_peaks2)
num_peaks = len(paired_peaks) + num_unpaired_peaks
mhi = compute_mhi(similarity_factor, num_peaks, num_unpaired_peaks)
print_with_c_locale(f'[experimental] Mechanical health: {mhi}')
fig, ((ax1, ax3)) = plt.subplots(
1,
2,
gridspec_kw={
'height_ratios': [4, 3],
'bottom': 0.050,
'top': 0.890,
'left': 0.085,
'right': 0.966,
'hspace': 0.169,
'wspace': 0.200,
'width_ratios': [5, 3],
'bottom': 0.080,
'top': 0.840,
'left': 0.050,
'right': 0.985,
'hspace': 0.166,
'wspace': 0.138,
},
)
fig.set_size_inches(8.3, 11.6)
fig.set_size_inches(15, 7)
# Add title
title_line1 = 'RELATIVE BELTS CALIBRATION TOOL'
fig.text(
0.12, 0.965, title_line1, ha='left', va='bottom', fontsize=20, color=KLIPPAIN_COLORS['purple'], weight='bold'
0.060, 0.947, title_line1, ha='left', va='bottom', fontsize=20, color=KLIPPAIN_COLORS['purple'], weight='bold'
)
try:
filename = lognames[0].split('/')[-1]
@@ -517,14 +498,19 @@ def belts_calibration(lognames, klipperdir='~/klipper', max_freq=200.0, st_versi
'Warning: CSV filenames look to be different than expected (%s , %s)' % (lognames[0], lognames[1])
)
title_line2 = lognames[0].split('/')[-1] + ' / ' + lognames[1].split('/')[-1]
fig.text(0.12, 0.957, title_line2, ha='left', va='top', fontsize=16, color=KLIPPAIN_COLORS['dark_purple'])
fig.text(0.060, 0.939, title_line2, ha='left', va='top', fontsize=16, color=KLIPPAIN_COLORS['dark_purple'])
title_line3 = f'| Estimated similarity: {similarity_factor:.1f}%'
title_line4 = f'| {mhi} (experimental)'
fig.text(0.55, 0.980, title_line3, ha='left', va='top', fontsize=14, color=KLIPPAIN_COLORS['dark_purple'])
fig.text(0.55, 0.945, title_line4, ha='left', va='top', fontsize=14, color=KLIPPAIN_COLORS['dark_purple'])
# Plot the graphs
plot_compare_frequency(ax1, lognames, signal1, signal2, similarity_factor, max_freq)
plot_difference_spectrogram(ax2, signal1, signal2, t, bins, combined_divergent, textual_mhi, max_freq)
plot_compare_frequency(ax1, signal1, signal2, signal1_belt, signal2_belt, max_freq)
plot_versus_belts(ax3, common_freqs, signal1, signal2, interp_psd1, interp_psd2, signal1_belt, signal2_belt)
# Adding a small Klippain logo to the top left corner of the figure
ax_logo = fig.add_axes([0.001, 0.8995, 0.1, 0.1], anchor='NW')
ax_logo = fig.add_axes([0.001, 0.894, 0.105, 0.105], anchor='NW')
ax_logo.imshow(plt.imread(os.path.join(os.path.dirname(os.path.abspath(__file__)), 'klippain.png')))
ax_logo.axis('off')