Data for the paper "A new proxy measurement algorithm with applications to estimation of vertical ground reaction forces using wearable sensors"

Guo, Y., Storm, F., Zhao, Y. et al. (2017) A new proxy measurement algorithm with application to the estimation of vertical ground reaction forces using wearable sensors. Sensors, 17 (10). 2181. ISSN 1424-8220. DOI:10.3390/s17102181<br><br>Measurement of the ground reaction forces (GRF) during
walking is typically limited to laboratory settings and only short observations
using wearable pressure insoles have been reported so far. In this study, a new proxy measurement method is proposed to estimate
the vertical component of the GRF (vGRF) from wearable accelerometer signals. The
accelerations are used as the proxy variable. An orthogonal forward regression
algorithm (OFR) is employed to identify the dynamic relationships between the
proxy variables and the measured vGRF using pressure-sensing insoles. The
obtained model, which represents the connection between the proxy variable and
the vGRF, is then used to predict the latter. The
results have been validated using pressure insoles data collected from nine
healthy individuals under two outdoor walking tasks in non-laboratory settings.
Results show that the vGRFs can be reconstructed
with high accuracy (with an average prediction error of less than 6%) using
only one wearable sensor mounted at forehead level. Proxy measures with different sensor positions are also discussed. Results show that the forehead accelerations
based proxy measurement is more stable with less inter-task and inter-subject
variability than the proxy measures using cervical and low back level
accelerations. The proposed proxy measure
provides a promising low-cost method for monitoring ground reaction forces in
real life settings and introduces a novel generic approach for replacing the direct determination of difficult to
measure variables in many applications.