Portable system for the linear and non-linear re-calibration of force platform

Force platforms (FPs) are routinely used in human movement analysis. Over time, the instrument sensitivity may change and cause undesired crosstalk between the output variables, leading to a lack of accuracy [1]. Further, a nonlinear behaviour can be present, mainly due to the bending under load of the FP top plate [2]. We propose here a system that re-calibrates the FP and, at the same time, quantifies and compensates for the force platform non-linearity. The system was experimentally tested on 4 commercial FPs, and its effectiveness was verified by quantifying the FPs accuracy in the COP measurement, before and after re-calibration.