Feed forward neural network that classifies the current physical activity of the user using accelerometer and gyroscope data from mobile phone.
Input Data:
- Triaxial acceleration from the accelerometer (total acceleration) and the estimated body acceleration.
- Triaxial Angular velocity from the gyroscope.
- A 561-feature vector with time and frequency domain variables.
- Activity Label
- An identifier of the subject who carried out the experiment.
Output classes: WALKING, WALKING_UPSTAIRS, WALKING_DOWNSTAIRS, SITTING, STANDING, LAYING
Data preprocessing:
- Features are normalized and bounded within [-1,1].
- Each feature vector is a row on the text file.
- The units used for the accelerations (total and body) are 'g's (gravity of earth -> 9.80665 m/seg2).
- The gyroscope units are rad/seg.
Model Structure:
- Input layer with 561 features
- Second layer with 100 neuron and RELU
- Third layer with 50 neuron and RELU
- Bang, dropout of .5 to fire off 50% random neuron
- Fourth layer with 25 neuron and RELU
- Fifth layer with 10 neuron and RELU
- Sixth layer with 5 neuron and RELU
- Last layer with 6 classification with softmax function, since it is a multi-class classification.
Dataset courtesy: https://archive.ics.uci.edu/ml/machine-learning-databases/00240/