System Power ON Battery supplies power to Arduino, EMG sensor, LCD, LEDs, and buzzer

User Setup • Place sEMG electrodes on target core muscles (SENIAM guidelines) • Press Start button

Personalized Calibration Phase • User performs controlled reference exercises (sit-ups / planks) • EMG signals recorded • Average activation profile calculated • Baseline stored in EEPROM

Real-Time Exercise Mode

sEMG Signal Acquisition • Muscle electrical activity captured • Sampling at 1 kHz

Signal Conditioning • Amplification (sensor level) • Full-wave rectification • Moving average filtering (100–200 ms)

Normalization • Current EMG compared with user baseline • Signal scaled to personalized reference

Threshold Analysis

Decision Logic • ≥ 90% match → Correct Form • 60–89% match → Insufficient Engagement • < 60% match → Incorrect Form – Adjust Posture

Feedback Output • LCD displays text feedback • RGB LEDs indicate intensity level • Buzzer signals start / completion

User Correction & Continuation • User adjusts posture or effort based on feedback

Stop Button Pressed? • No → Loop back to sEMG Signal Acquisition • Yes → End session

System OFF