Evaluation of a long-range transmitter for use with a magnetic tracking device in motion analysis.

The suitability of a long-range transmitter was evaluated for use with a Polhemus Fastrak magnetic tracking device in kinesiologic studies. Performance was judged by comparing positional and rotational accuracy to a standard transmitter. Data were obtained at distances of up to 2.7 and 5.0 m for the standard and long-range transmitters, respectively. Use of the long-range transmitter improved system performance allowing reproducible measurements at a greater distance. However, it is necessary to calibrate the system in each new test environment as there can be significant distortion of the magnetic field.