HUMAN ACTIVITY RECOGNITION

Initializing ML System

UNDERSTAND HUMAN MOVEMENT USING SENSOR DATA

An advanced machine learning system trained on the official UCI Human Activity Recognition dataset, analyzing 561-dimensional smartphone sensor readings to classify activities with high accuracy.

X (Acc) Y (Gravity) Z (Gyro)
Smartphone Sensor Array

ACTIVITY PREDICTOR

Describe the movement using simple observable characteristics to find and analyze real dataset observations.

Questionnaire

Adjust the parameters to select matching smartphone recordings from the real UCI test set.

Specifies the overall amplitude of linear body acceleration.
Measures signal jerkiness or sudden changes in acceleration.
The orientation of the device relative to gravity.
Measures rotational velocity (angular speed) from the gyroscope.
The rhythmicity or periodicity of the movement.

Analysis Result

šŸ“Š

Configure the physical descriptors and click Analyze Activity to run machine learning predictions on matching records.

ANALYZE REAL UCI RECORDING

Directly load individual 561-dimensional rows from the official test dataset (`X_test`) to evaluate model predictions against ground truth (`y_test`).

Sample Selection

Choose a test sample between index 1 and 2,947 to inspect. The backend loads the exact feature vector from `X_test.txt` and queries the ML model.

Verification Results

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Select a sample index and click Analyze Sensor Recording to inspect the row data and model decision.

LIVE SENSOR PREDICTOR

Real-time smartphone activity classification using a 128-sample sliding window, 50 Hz resampling, 3D gravity alignment, digital signal processing, and a trained ML model.

šŸ“± Sensor Stream
→
šŸ”„ 50Hz Resample
→
šŸ“ 3D Gravity Align
→
šŸ”¬ DSP (Filters + FFT)
→
šŸ¤– Scaled ML Model
→
āœ… Smooth Prediction

Sensor Access

This mode uses your device's motion sensors via the browser DeviceMotion API. Open this page on your smartphone and grant sensor permission to begin.

Checking device sensor support...

Current Activity

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Waiting for sensor access. Grant permission and hold your phone to begin classifying activity.

MODEL DASHBOARD

Real-time statistics and training evaluation metrics saved in the system metadata.

Model Visualizations

Confusion Matrix Chart

Confusion matrix for the selected model. Displays counts of correct classifications vs misclassifications per class.

Model Comparison Chart

Accuracy comparison across all tested machine learning algorithms on the official test set.

Activity Distribution Chart

Counts of observation samples representing each activity in the training dataset.

HOW IT WORKS

Understanding the signal processing and machine learning pipeline.

1

Smartphone Sensors

Triaxial raw accelerometer (linear acceleration) and gyroscope (angular velocity) signals captured at 50 Hz.

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2

Signal Processing

Noise filtering and gravity/body acceleration separation using low-pass Butterworth filters (0.3 Hz corner).

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3

Feature Engineering

Extraction of 561 time and frequency domain variables (mean, standard deviation, entropy, autoregression, etc.).

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4

Trained ML Model

Multi-class classification using an optimized Support Vector Machine (SVM) running on the 561 features.

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5

Activity Prediction

Output of final predicted activity name along with exact class probability distribution.

šŸ”¬ Scientific Note on Sensor Compatibility

Important: This web application uses real recorded smartphone sensor data from the official UCI dataset. It does not pull live readings from your phone's browser.

To support live phone integration, raw values (Acc X/Y/Z, Gyro X/Y/Z) cannot be directly fed into the model. They must first undergo windowing and identical digital signal processing (DSP) to extract the exact 561 features on which the SVM was trained.

THE SIX CLASSIFIED ACTIVITIES

Review characteristics of each classified physical movement.

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Walking

Dynamic cyclic gait on flat ground. Marked by regular body acceleration peaks and moderate rotation velocity.

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Walking Upstairs

Dynamic traversal upward. Shows higher body acceleration intensity and moderate orientation deviation.

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Walking Downstairs

Downward descent with high impact peaks. Typically exhibits maximum acceleration variation (low stability).

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Sitting

Static seated position. Minimal body acceleration, highly stable gravity alignment along vertical axes.

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Standing

Static standing position. Very low motion amplitude, stable vertical alignment of the phone.

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Lying

Static horizontal orientation. Gravity vector shifts completely along horizontal axes of the phone.