Abstract:

The accuracy of electromagnetic tracking system is impaired seriously by distortions of magnetic fields caused by metals which are omnipresent at real sites. To study the rules of magnetic distortion, the parallel finite difference in time domain (FDTD) algorithm is presented on a distributed network. The message passing module and space decomposition technique are introduced. In FDTD application，simulation of low frequency exciting source is very difficult. The fast Fourier transform (FFT) algorithm is introduced to analyze the magnetic field characteristic in some special frequency. Calibration arithmetic is proposed by modifying the transmitting matrix based on the concept of error calibration matrix. This matrix is calculated by the method of orthogonal polynomial fitting. The simulation results validate the correction of the calibration arithmetic, which improves the accuracy of the electromagnetic tracking system. The efficiency of calibration validation is improved by decreasing the work of data collection, which is based on the results of numerical simulation.