A movement tracking device that includes a housing, a rotatable spool secured within the housing, a rotary sensor in operable communication with the spool, and a conductive wire configured to be repeatedly unspooled from and respooled onto the rotatable spool. The conductive wire has a distal end extendable from the housing. The movement tracking device also includes a plurality of resonators and a processor in communication with the plurality of resonators and the rotary sensor. The plurality of resonators are disposed in or on the housing and positioned about the conductive wire. Each of the plurality of resonators is configured to create one or more magnetic fields through which the conductive wire extends. The processor is configured to receive information from the plurality of resonators and the rotary sensor and determine a position of the conductive wire.

A localization and attitude estimation method using magnetic fields includes the following steps. First, in three-dimensional coordinates, at least three magnetic landmarks arbitrarily disposed around a moving carrier are selected, wherein any two of the at least three magnetic landmarks have different magnetic directions. One set of at least five tri-axes magnetic sensors is used to sense the magnetic fields of the at least three magnetic landmarks. Three magnetic components on three axes of a current position of each of the tri-axes magnetic sensors are respectively generated by a demagnetization method. Five non-linear magnetic equations are solved to obtain position information and magnetic moment information of the at least three magnetic landmarks in the three-dimensional coordinates. Position vectors and attitude vectors of the set of at least five tri-axes magnetic sensors in a three-dimensional space are estimated based on tri-axes magnetic moment vectors of the magnetic landmarks.

A localization and attitude estimation method using magnetic fields includes the following steps. First, in three-dimensional coordinates, at least three magnetic landmarks arbitrarily disposed around a moving carrier are selected, wherein any two of the at least three magnetic landmarks have different magnetic directions. One set of at least five tri-axes magnetic sensors is used to sense the magnetic fields of the at least three magnetic landmarks. Three magnetic components on three axes of a current position of each of the tri-axes magnetic sensors are respectively generated by a demagnetization method. Five non-linear magnetic equations are solved to obtain position information and magnetic moment information of the at least three magnetic landmarks in the three-dimensional coordinates. Position vectors and attitude vectors of the set of at least five tri-axes magnetic sensors in a three-dimensional space are estimated based on tri-axes magnetic moment vectors of the magnetic landmarks.

A laser measuring system including first and second laser base stations and a laser receiver is provided. The laser receiver detects a first laser signal from the first laser base station. Location information associated with the first laser base station is extracted from the detected first laser signal. The laser receiver detects a second laser signal from the second laser base station. Location information associated with the second laser base station is extracted from the detected second laser signal. A position of the laser receiver is determined based on the extracted location information associated with the first laser base station and the extracted location information associated with the second laser base station.

A laser measuring system including first and second laser base stations and a laser receiver is provided. The laser receiver detects a first laser signal from the first laser base station. Location information associated with the first laser base station is extracted from the detected first laser signal. The laser receiver detects a second laser signal from the second laser base station. Location information associated with the second laser base station is extracted from the detected second laser signal. A position of the laser receiver is determined based on the extracted location information associated with the first laser base station and the extracted location information associated with the second laser base station.

A calibration method includes receiving magnetic field values, which are generated by a plurality of real magnetic transmitters and are measured at multiple positions on a grid in a region containing a magnetic field perturbing element. Approximate locations of the real magnetic transmitters are received. Using the approximate locations, a respective plurality of imaginary magnetic sources is characterized inside the field perturbing element. Using the measured magnetic field values, the approximate locations, and the characterized imaginary sources, there are iteratively calculated (i) actual locations of the real and imaginary magnetic sources in the region, and (ii) modeled magnetic field values that would result from the real and imaginary magnetic sources at the actual locations. Using the calculated locations, and the modeled magnetic field values at the multiple positions on the grid, a magnetic field calibration function is derived for the region.

A calibration method includes receiving magnetic field values, which are generated by a plurality of real magnetic transmitters and are measured at multiple positions on a grid in a region containing a magnetic field perturbing element. Approximate locations of the real magnetic transmitters are received. Using the approximate locations, a respective plurality of imaginary magnetic sources is characterized inside the field perturbing element. Using the measured magnetic field values, the approximate locations, and the characterized imaginary sources, there are iteratively calculated (i) actual locations of the real and imaginary magnetic sources in the region, and (ii) modeled magnetic field values that would result from the real and imaginary magnetic sources at the actual locations. Using the calculated locations, and the modeled magnetic field values at the multiple positions on the grid, a magnetic field calibration function is derived for the region.

A method includes providing a jig including a predetermined center and a magnetron installed on the jig; rotating the magnetron and obtaining a measured first magnetic flux density at the predetermined center of the jig; defining a first area of the magnetron based on the measured first magnetic flux density; rotating the magnetron and measuring a plurality of second magnetic flux densities within the first area of the magnetron; deriving a measured second magnetic flux density among the plurality of second magnetic flux densities; comparing the measured second magnetic flux density with a predetermined threshold; and performing an operation based on the comparison.

A method includes providing a jig including a predetermined center and a magnetron installed on the jig; rotating the magnetron and obtaining a measured first magnetic flux density at the predetermined center of the jig; defining a first area of the magnetron based on the measured first magnetic flux density; rotating the magnetron and measuring a plurality of second magnetic flux densities within the first area of the magnetron; deriving a measured second magnetic flux density among the plurality of second magnetic flux densities; comparing the measured second magnetic flux density with a predetermined threshold; and performing an operation based on the comparison.

Disclosed is a method for calibrating at least one gap sensor, the at least one gap sensor being provided on a magnetic bearing supporting a floating body in a non-contact manner by an electromagnetic force, the at least one gap sensor being configured to detect a gap between the floating body and a reference object that serves as a positional reference for position control of the floating body. The method includes: constructing a transformation formula for transforming an output of the at least one gap sensor into the gap using three or more constraints that are set as conditions for associating the gap with the output of the at least one gap sensor.