Disconnected
Real-time biosignal analysis
PPG signal pipeline · 0 beats this session
Heart rate
--bpm
Waiting for signal...
Composite stress
--/100
WaitingSI --
SpO₂
--%
PI -- · SQI --
RMSSD · vagal tone
--ms
SDNN -- ms · pNN50 --%
HRV frequency decomposition
Welch PSD · 4 Hz interpolated tachogram
Collecting RR intervals for spectral analysis...
VLF
--ms²
LF
--ms²
0.04 to 0.15 HzHF
--ms²
0.15 to 0.40 HzTask Force of the ESC/NASPE (1996). Heart rate variability standards of measurement.
Poincaré plot
RR(n) vs RR(n+1) nonlinear dynamics
SD1
--ms
SD2
--ms
DFA α1
--
SampEn
--
Brennan et al. (2001). SD1/SD2 = short/long-term variability descriptors.
Autonomic state
Parasympathetic ↔ Sympathetic quadrant
Para index
--
Symp index
--
Coherence
--
Shaffer & Ginsberg (2017). Overview of HRV metrics and norms.
Respiratory rate fusion
PPG · ECG-derived · IMU chest-wall motion
PPG
0.0
IMU
0.0
Fused
--rpm
PPG resp
--rpm
IMU resp
--rpm
Charlton et al. (2018). Breathing rate estimation from the ECG and PPG.
Baevsky stress index
Geometric RR histogram method
SI
--
Composite
--/100
LF/HF
--
Baevsky & Chernikova (2017). Heart rate variability analysis methodology.
Signal quality
Skewness · template · perfusion index
Composite SQI0.00
Skewness0.00
Template corr0.00
Perfusion idx0.00
Elgendi (2016). Optimal signal quality index for photoplethysmogram signals.
Fidget & activity breakdown
IMU-derived MET intensity categories
No IMU sensor connected. Plug in BMI323 to see activity data
Steps
--
Fidget
--/100
Posture
--
IMU Resp
--rpm
Freedson et al. (1998). Calibration of the Computer Science and Applications accelerometer.
24-hour trend
Circadian HR × HRV overlay
Collecting heartbeat data for trend...
Mean HR
--bpm
RMSSD
--ms
SDNN
--ms
Beats
0
Kleiger et al. (1987). Decreased HRV and its association with increased mortality.
ECG analysis
R-peak detection, RR interval histogram
RR interval distribution
ECG HR
--bpm
R-peaks
0
Mean RR
0ms
Pan J, Tompkins WJ (1985). A real-time QRS detection algorithm.
IMU analysis
Fidget detection, step counting, posture
Fidget intensity--/100
upright
slouching
lying
Steps
--
Fidget
--/100
IMU Resp
--rpm
Posture
--
Freedson PS et al. (1998). Calibration of the CSA accelerometer.
Temperature analysis
24h circadian curve with cosinor fit
MeasuredCosinor fit
Current
--°C
Samples
0
Min
--°C
Max
--°C
Refinetti R et al. (2007). Procedures for numerical analysis of circadian rhythms.
Multi-sensor fusion
Composite stress with per-source contributions
--/100 Waiting
HRV (PPG)
35%
ECG
25%
Fidget (IMU)
20%
Resp rate
12%
Temperature
8%
Autonomic state quadrant
Symp+Para+
Composite
--/100
State
Waiting
Para idx
--
Symp idx
--
Bolkhovsky et al. (2012). Statistical analysis of HRV and clinical scoring of ANS.