Abstract: Systems and methods for discriminating and locating tissues within a body involve applying a waveform signal to tissue between two electrodes and measuring the electrical characteristics of the signal transmitted through the tissue. At least one of the electrodes is constrained in area so that localized electrical characteristics of the tissue are measured. Such localized electrical characteristics are determined over a portion of a body of the subject by using an array of electrodes or electrodes that can be moved over the body. A controller may implement the process and perform calculations on the measured data to identify tissue types and locations within the measured area, and to present results in graphical form. Results may be combined with other tissue imaging technologies and with image-guided systems.

Abstract: Systems and methods for discriminating and locating tissues within a body involve applying a waveform signal to tissue between two electrodes and measuring the electrical characteristics of the signal transmitted through the tissue. At least one of the electrodes is constrained in area so that localized electrical characteristics of the tissue are measured. Such localized electrical characteristics are determined over a portion of a body of the subject by using an array of electrodes or electrodes that can be moved over the body. A controller may implement the process and perform calculations on the measured data to identify tissue types and locations within the measured area, and to present results in graphical form. Results may be combined with other tissue imaging technologies and with image-guided systems.

Abstract: Described are an automated system, an apparatus, and a method adapted to tracking and dynamically measuring locations in a volume for determining a size and a position of a body during a performance of a repetitive motion, such as in using sporting equipment. The sporting equipment may be a bicycle, and the body may be a cyclist. The apparatus comprises a plurality of markers attached to the body, a three-dimensional marker tracking system, and a processing unit. The apparatus, system, or method computes a dimensional statistic from computed measurements of all strokes of at least two strokes included in a period of time of the repetitive motion.

Abstract: A method or a system embodiment determines positional information about a moveable object to which is affixed a pattern of stripes having reference lines. A method determines image lines of stripe images of each stripe within at least two video frames, uses the image lines to prescribe planes having lines of intersection, and determines a transformation mapping reference lines to lines of intersection. Position information about the object may be derived from the transformation. A system embodiment comprises a pattern of stripes in a known fixed relationship to an object, reference lines characterizing the stripes, two or more cameras at known locations, a digital computer adapted to receive video frames from the pixel arrays of the cameras, and a program stored in the computer's memory. The program performs some or all of the method.

Abstract: The shape and orientation of rigid or nearly rigid moveable bodies are determined using a shape characterization. Sensors capture a plurality of representations of different perspectives of the body that are analyzed to determine a bounding volume of the body. The shape of the body is determined from the bounding volume. The position of the body is determined using tracking devices that sense the position of the body. The bounding volume and position information are combined to define the shape and orientation in space of the body, and in particular the position of a point of interest on the body.

Abstract: The shape and orientation of rigid or nearly rigid moveable bodies are determined using a shape characterization. Sensors capture a plurality of representations of different perspectives of the body that are analyzed to determine a bounding volume of the body. The shape of the body is determined from the bounding volume. The position of the body is determined using tracking devices that sense the position of the body. The bounding volume and position information are combined to define the shape and orientation in space of the body, and in particular the position of a point of interest on the body.

Abstract: A sensor for determining a component of a location of a radiation source within a three dimensional volume includes a mask having a series of openings that has a predetermined mathematical relationship among the openings within the series of openings and defines a mask reference line; a detector surface spaced from the mask where radiation passing through the mask creates a mask image on the detector surface having a series of peaks and an image reference line within the mask image that can be located and where at least 50% of the mask image is projected onto the detection surface; and a calculating unit to determine a location of the image reference line within the mask image and the component of the location of the radiation source from the calculated location of the image reference line within the mask image. A method and system for using this sensor are also disclosed.

Abstract: A method and system for discriminating tissues in a subject, particularly for identifying nerve tissue, includes a processor, a waveform generator, a waveform electrode and a return electrode and an electrical property measuring device such as a volt meter. The electrodes are applied to the skin of the subject and an electrical waveform applied to the tissue via the electrodes. A series of electrical property measurements between the electrodes yield digital data that is used to determine coefficients of an approximating mathematical function, which is then used to derived electrical properties of the tissue. Derived electrical properties are then displayed on a display device.

Abstract: Systems and methods for discriminating and locating tissues within a body involve applying a waveform signal to tissue between two electrodes and measuring the electrical characteristics of the signal transmitted through the tissue. At least one of the electrodes is constrained in area so that localized electrical characteristics of the tissue are measured. Such localized electrical characteristics are determined over a portion of a body of the subject by using an array of electrodes or electrodes that can be moved over the body. A controller may implement the process and perform calculations on the measured data to identify tissue types and locations within the measured area, and to present results in graphical form. Results may be combined with other tissue imaging technologies and with image-guided systems.

Abstract: The method of this invention, and the apparatus which implements it, provides a way of sampling points on the surface of a portion of a rigid or semi-rigid object, which might be an anatomical body. Points are sampled by a moveable contact probe which emits a sonic waveform under the direction of a control unit. Multiple fixed sonic transducers in contact with the object at diverse locations detect the waveform, the arrival of which is timed for each transducer by the control unit. Given the speed of sound in the object and the coordinates of the transducers, a digital computer can compute the location of the probe. Two ways are presented to calibrate the locations of the transducers. Provision is made for mitigating possible distortion of soft object surfaces due to the contact force of the probe. During the sampling of probe contact locations, at least one physical or physiological attribute is also acquired.

Abstract: The method of this invention, and any apparatus which implements it, improves the accuracy of determining the sub-pixel location of the image of a point-like radiator of energy (typically light). This method distributes the image of a point radiator of energy over detector pixels such that the number of image pixels with high intensity gradients is maximized, while it minimizes the energy wasted on pixels with low intensity gradients, which contribute little to the computation of the sub-pixel location of the image. By improving such accuracy in each of one or more cameras, the accuracy of deriving the spatial location of the energy radiator improves also.

Abstract: A sensor for determining a component of a location of a radiation source within a three dimensional volume includes a mask having a series of openings that has a predetermined mathematical relationship among the openings within the series of openings and defines a mask reference line; a detector surface spaced from the mask where radiation passing through the mask creates a mask image on the detector surface having a series of peaks and an image reference line within the mask image that can be located and where at least 50% of the mask image is projected onto the detection surface; and a calculating unit to determine a location of the image reference line within the mask image and the component of the location of the radiation source from the calculated location of the image reference line within the mask image. A method and system for using this sensor are also disclosed.

Abstract: This invention is a system that tracks the 3-dimensional position and orientation of one or more bodies (20) in a volume by a light based as well as at least one non-light based mensuration sub-system. This overcomes the limitation of light based mensuration systems to the necessity of the bodies (20) to be in constant line-of-sight of its light based position sensors (26). The invention possesses most of the accuracy and stability of its light based position measurement sub-system (24, 26, 72), but can also work without direct line of sight either for short periods of time or within certain parts of the volume. It does so by incorporating other sensors (31, 34), such as inertial or magnetic, which are frequently recalibrated against the light based sub-system (24, 26, 72) while the bodies (20) are visible by the light based sub-system (24, 26, 72).

Abstract: Disclosed is a wireless instrument tracking system. The wireless instrument tracking system is used for determining the location of at least one point relative to the instrument in a three-dimensional space relative to a three-dimensional coordinate tracking system. Advantageously, a first wireless instrument can be placed into the optical field with the wireless instrument including a wireless receiver and at least one optical position indicator. The optical position indicator is typically light emitting diodes (18) and communicates with corresponding measurement sensors (30) across a wireless optical link. The wireless optical link is time multiplexed with repetitive time frames divided into time slots. Each LED (18) emits an infrared signal or flashes in a respective time slot of a time frame. The measurement sensors (30) are preferably CCD cameras.

Abstract: An optical improvement for angular position sensors, which may be used to determine the spatial coordinates of a small source of light (or other energy) in a 3-dimensional volume. Such sensors normally include a linear photosensitive image detector such as a photodiode array or a charge-coupled device (CCD). An irregular pattern of parallel slits is described which increases the amount of light gathered while avoiding the undesirable characteristics of lens optics for this application. One optimal type of irregular pattern is the uniformly redundant array. A mathematical correlation function together with a polynomial interpolation function can determine the displacement of the image on the detector and thereby the location of the source relative to one angular dimension. Given the locations and orientations of several sensors in a 3-dimensional coordinate system and given the angles measured by each, the location of the point source can be computed.

Abstract: System for sensing at least two points on an object for determining the position and orientation of the object relative to another object. Two light emitters mounted in spaced relation to each other on an external portion of an invasive probe remaining outside an object into which an invasive tip is inserted are sequentially strobed to emit light. Three light sensors or detectors, the positions of which are known with respect to a predetermined coordinate system, detect the positions of the two light emitters positioned on the probe. A computer connected to the probe and to the light sensors receives data from the sensors and determines the position and orientation of the probe relative to the predetermined coordinate system.

Abstract: Locating and displaying the relative positions of two objects in a three-dimensional space where one object is a three-dimensional object and the second object has at least three collinear points, at least two of which are sensible by a detector. The detector supplies signals providing azimuth and altitude information related to the two sensible points of the second object for locating the position of at least the third point of the second object relative to the first object which may be positioned inside or outside the boundaries of the first object. The first object may have fixed thereto at least three points sensible by the detector for establishing the position and attitude of the first object within the three-dimensional space.

Abstract: Improved point source electromagnetic radiation emitters including a dispersing element that radiates electromagnetic radiation over a very wide conical angle of approaching about 180.degree.. This light dispersing element can be in any one or more of several illustrated forms such as a light diffusing spherical or hemispherical element, a planar diffusing plate, a tapered light guide, a plano-concave lens, a convex mirror, a light pipe with a large numerical aperture, or the like. The emitter of this invention may be fixed to an object and tracked in a 3-dimensional volume by a system using electro-optical position sensors in order to determine the spatial location of the emitters and therefore to determine, by geometry, the position and orientation of the object. The electromagnetic radiation generator is preferably disposed remote from the emitter and is electrically and magnetically isolated from the emitter. A common optical fiber provides transmission of the radiation from the generator to the emitter.

Abstract: Improved point source electromagnetic radiation emitters including a dispersing element that radiates electromagnetic radiation over a vary wide conical angle of approaching about 180°. This light dispersing element can be in any one or more of several illustrated forms such as a light diffusing spherical or hemispherical element, a planar diffusing plate, a tapered light guide, a piano-concave lens, a convex mirror, a light pipe with a large numerical aperture, or the like. The emitter of this invention may be fixed to an object and tracked in a 3-dimensional volume by a system using electro-optical position sensors in order to determine the spatial location of the emitters and therefore to determine, by geometry, the position or orientation of the object. The electromagnetic radiation generator is preferably disposed remote from the emitter and is electrically and magnetically isolated from the emitter. A common optical fiber provides transmission of the radiation from the generator to the emitter.

Abstract: This method and apparatus optically samples numerous points on the surface of an object to remotely sense its shape utilizing two stages. The first stage employs a moveable non-contact scanner, which in normal operation sweeps a narrow beam of light across the object, illuminating a single point of the object at any given instant in time. The location of that point relative to the scanner is sensed by multiple linear photodetector arrays behind lenses in the scanner. These sense the location by measuring the relative angular parallax of the point. The second stage employs multiple fixed but widely separated photoelectronic sensors, similar to those in the scanner, to detect the locations of several light sources affixed to the scanner, thereby defining the absolute spatial positions and orientations of the scanner. Individual light sources are distinguished by time-multiplexing their on-off states.