SteadyStateDetectionEvents¤
Identify when a process signal has settled into a steady operating state versus transient/dynamic periods.
Module: ts_shape.events.engineering.steady_state_detection
Guide: Process Engineering
When to Use¤
Use to segment process data into steady-state vs transient periods. Essential for valid statistical analysis — SPC and capability indices are only meaningful on steady-state data. Also useful for filtering out startup, shutdown, and transition periods before computing KPIs.
Quick Example¤
from ts_shape.events.engineering.steady_state_detection import SteadyStateDetectionEvents
detector = SteadyStateDetectionEvents(
df=process_data,
uuid="reactor_temperature_01"
)
# Detect steady-state intervals
steady = detector.detect_steady_state(
window="5m",
std_threshold=1.0,
min_duration="10m"
)
# Get transient periods (inverse of steady state)
transients = detector.detect_transient_periods(
window="5m",
std_threshold=1.0
)
# Identify distinct operating bands within steady state
bands = detector.steady_state_value_bands(window="5m")
Key Methods¤
| Method | Purpose | Returns |
|---|---|---|
detect_steady_state(window='5m', std_threshold=1.0, min_duration='10m') |
Steady-state intervals | DataFrame of steady intervals |
detect_transient_periods(window='5m', std_threshold=1.0) |
Transient/dynamic intervals | DataFrame of transient intervals |
steady_state_statistics(window='5m') |
Summary statistics | DataFrame with steady-state stats |
steady_state_value_bands(window='5m') |
Distinct operating bands | DataFrame of value bands |
Tips & Notes¤
Tune std_threshold to your process noise
The default std_threshold=1.0 works for many signals, but noisy sensors may need a higher value. Start by looking at steady_state_statistics() output and adjust until the detected intervals match your engineering judgment.
Related modules
- Process Windows — windowed statistics that pair well with steady-state filtering
- Setpoint Events — detect the setpoint changes that cause transient periods
- Operating Range — analyze the envelope within steady-state periods