Abstract: A magnetic tracking device is configured to track an object in an environment by receiving a measurement of the non-magnetic signal and a corresponding measurement of the magnetic signal for a location of the magnetic tracking device in the environment. The magnetic tracking device estimates, based on the measurement of the non-magnetic signal, a non-magnetic pose of the magnetic tracking device in the environment for the location. The device estimates, based on the measurement of the magnetic signal, a magnetic pose of the magnetic tracking device in the environment for the location. The device determines a difference between the magnetic pose estimate and the non-magnetic pose estimate for the location. The device determines a magnetic distortion correction value for the location based on the difference. The magnetic tracking device generates a distortion correction model including the distortion value and outputs a representation of the distortion correction model.

Abstract: A magnetic tracking device is configured to track an object in an environment by receiving a measurement of the non-magnetic signal and a corresponding measurement of the magnetic signal for a location of the magnetic tracking device in the environment. The magnetic tracking device estimates, based on the measurement of the non-magnetic signal, a non-magnetic pose of the magnetic tracking device in the environment for the location. The device estimates, based on the measurement of the magnetic signal, a magnetic pose of the magnetic tracking device in the environment for the location. The device determines a difference between the magnetic pose estimate and the non-magnetic pose estimate for the location. The device determines a magnetic distortion correction value for the location based on the difference. The magnetic tracking device generates a distortion correction model including the distortion value and outputs a representation of the distortion correction model.

Abstract: A sensor for determining the angular position of a radiating point source in two dimensions includes a mask encoded in two skewed directions with waveforms consisting of several frequencies in prescribed patterns. The frequency spectra of the received detector patterns are computed. In order to facilitate such computations, the constituent frequencies are separated so as to be distinguished in the Fast Fourier Transform (FFT). Each of the frequency patterns that are coded on the variable transmissivity mask consists of a series of low frequencies followed by a series of variable frequencies, and a series of high frequencies. The variable frequencies exhibit frequency changes responsive to various image positions. The low and high frequencies are responsive in phase to variations in image position. The frequency variations in the variable frequencies are used to indicate coarse position while the phases of the fixed low and high frequencies are used to indicate medium and fine position.

Abstract: A sensor for determining the angular position of a radiating point source in two dimensions includes a mask encoded in two skewed directions with waveforms consisting of several frequencies in prescribed patterns. The frequency spectra of the received detector patterns are computed. In order to facilitate such computations, the constituent frequencies are separated so as to be distinguished in the Fast Fourier Transform (FFT). Each of the frequency patterns that are coded on the variable transmissivity mask consists of a series of low frequencies followed by a series of variable frequencies, and a series of high frequencies. The variable frequencies exhibit frequency changes responsive to various image positions. The low and high frequencies are responsive in phase to variations in image position. The frequency variations in the variable frequencies are used to indicate coarse position while the phases of the fixed low and high frequencies are used to indicate medium and fine position.