Algorithm Development — SensorDataToolbox
The SensorDataToolbox is a collection of algorithms and workflows that are used in a variety of mobile inertial sensor data analysis applications. Implementations in the toolbox are mainly MATLAB code with occasional C/C++ implementations for performance reasons. The purpose for this project is a common code-base for the group that can also be used to archive implementations created in the various projects. Currently, the SensorDataToolbox contains generally applicable methods for
- Various preprocessing steps (calibration, normalization, resampling, filtering, etc.)
- Segmentation of sensor data (mulit-dim. subsequence dynamic time warping, sliding window)
- Double-integration of inertial sensor data to arrive at sensor trajectories over time
- Extraction of statistical parameters from segments of data e.g. defined by the segmentation
In the case of inertial sensor data from human gait, the prototypical application the toolbox is developed by, a set of biomechanical events (toe-off, heel-strike and mid-stance) can be extracted from the segmentation of continuous sensor data into strides. Furthermore, several biomechanical parameters can be extracted from the sensor trajectories for each stride (stride length, width etc.) or from the timings of individual gait events (stride, swing and stance time). In this respect, the toolbox also constitutes the code-base for the EFIMoves project and allows efficient deployment of graphical user interfaces that can be used in a clinical setting for advanced gait analysis.