Nonlinear interpolation of mandibular kinesiographic signals by applying sensitivity method to a GMDH correction model

An improved nonlinear interpolation method for estimating distorted kinesiographic recording of interlattice points in space is proposed, and its correction accuracy is evaluated. The group method of data handling (GMDH) correction method reported previously by the authors (1984, 1986) can be adapted to a measurement environment in which kinesiographic signals are subject to ferromagnetic interferences, but it was restricted to kinesiographic signals representing lattice points in space. The sensitivity method for GMDH correction modeling is explored. This provides for nonlinear interpolation of kinesiographic signals for lattice points. Nominals, i.e., true values, of 3-D coordinates of the interlattice points were determined by means of a mandibular jaw movement simulator together with simultaneous recording of distorted kinesiographic signals which correspond to the nominals. Distorted signals were corrected by the new method of correction modeling. A mean estimation error of 0.16 mm (SD 0.19 mm) was determined for 24 interlattice coordinates. Thus, nonlinear interpolation by the sensitivity method is confirmed to be effective.