Abstract: A distance measurement system employs a monochromatic coherent light source which produces an outgoing ray which impinges upon a target reflector which reflects the beam back as a reflected beam to an interferometry detector. A portion of the outgoing ray also is delivered to the interferometry detector. As the target reflector position is changed, the interferometry detector continuously calculates changes in distance of the target reflector. The orientation angles of the target reflector are constantly and automatically adjusted so that the reflected light beam accurately strikes the interferometry detector. A misalignment detector senses the elevation offset and the azimuth offset of the target reflector and creates corresponding signals.

Abstract: A contactor device includes a magnetic latch apparatus to reduce bounce between contact pads on closing. The magnetic latch apparatus includes a first magnet assembly and a second magnet assembly disposed so as to magnetically latch the first contact pad and second contact pad in the closed position. The first and second magnet assemblies typically are disposed respectively on the first contact pad carrier and second contact pad carrier such that the distance between the first and second magnet assemblies corresponds to the distance between the first and second contact pads. The magnet assemblies have a latch element that is a permanent magnet, an electromagnet, or a magnetically attracted material.

Abstract: Time sampled data from many hundreds of sensors spatially arranged on a subject is acquired, displayed and archived in real-time. A redundant array of acquisition processors coupled to temporary storage device are controlled by a system control processor. As the data is acquired, an operator interacts with a display processor to select sensors mapped on a computer model of the subject. The selected sensors are displayed as real-time `postage stamp` traces each located in a position reflecting their position on the subject. During acquisition in the background, or at some time later, the acquired data is archived onto a slower, but much larger data storage device such as a stream tape, or optical disk.

Abstract: An enhanced reality maintenance system for operating in a hazardous or inaccessible environment employs an environment modeler which is supplied with spatial parameters of a given environment and creates a computer model of the environment. An environment renderer creates a plurality of images, each corresponding to a viewing location and orientation, `viewpoint`. A remotely operated vehicle (ROV) attached to a base unit by a tether cord or radio link navigates in the environment. The ROV has a spatial imaging device, such as a video camera, and actuators which propel it through the environment. Its position and orientation are determined by a position and attitude (P&A) sensing unit, and are passed to an ROV renderer which creates an image of a prestored model of the ROV having the same location and orientation as the ROV and viewed from a specified viewpoint. The viewpoints may be predetermined, provided to the system or may be interactively determined as an offset from the ROV position and orientation.

Abstract: A real-time data processing system employs a control computer which defines a pre-processing arrangement of data channels to speed processing, and an arrangement of output data channels to provide a desired output format. The data channels are samples and arranged into a data packet which is passed to an array of digital signal processors (DSPs) arranged in a series of stages, with at least one DSP per stage. A front-end DSP receives the data packet and appends a control field having commands addressed to specific DSPs to the data packet along with adding a monitor field. The DSPs monitor the control field for commands addressed to it and then executes those. The status of the operation is written in the monitor field and the data packet is passed to DSPs of the next stage for `pipelined` processing. DSPs of the last stage collect the process portions of the data packet, assemble them according to the desired output format and pass on the completed data packet.

Abstract: A 3D model of a subject is acquired. Sensors spatially located on the subject are displayed on the 3D model in their appropriate locations. An operator selects the proper viewing angle and sensors to monitor via input devices. A 3D modeler in a display processor provides an image viewed from the proper angle and identifies the selected sensors. The 3D modeler identifies the data channels which correspond to the selected sensors and provides these to a system control computer which then provides the samples for these data channels. The 3D modeler also identifies a screen location which pertains to the locations of the selected sensors on the model. A postage stamp trace unit receives the samples for the selected data channels and the screen locations pertaining to the selected sensor locations of the image of the model and produces a video signal representing a window having a number of real-time traces each pertaining to a sensor.

Abstract: An enhanced reality maintenance system for operating in a hazardous or inaccessible environment employs an environment modeler which is supplied with spatial parameters of a given environment and creates a computer model of the environment. An environment renderer creates a plurality of images, each corresponding to a viewing location and orientation, `viewpoint`. A remotely operated vehicle (ROV) attached to a base unit by a tether cord or radio link navigates in the environment. The ROV has a spatial imaging device, such as a video camera, and actuators which propel it through the environment. Its position and orientation are determined by a position and attitude (P&A) sensing unit, and are passed to an ROV renderer which creates an image of a prestored model of the ROV having the same location and orientation as the ROV and viewed from a specified viewpoint. The viewpoints may be predetermined, provided to the system or may be interactively determined as an offset from the ROV position and orientation.

Abstract: An apparatus for real-time tracking of a catheter guide wire in a patient undergoing an interventional radiological procedure includes an image processing unit for processing digitized fluoroscopic images from a fluoroscope image output. The image processor utilizes a novel algorithm for locating the image of a catheter in the fluoroscopic image. The image processor creates a two-dimensional model of the catheter for dynamic display on an operating room live image video monitor.

Abstract: A method for measuring a local magnetic signal by estimating and eliminating the effects of one or more remote magnetic noise sources is provided. The method relies on "tagging" the undesired noise component of the local measurement in such a way as to allow separation of the noise component from the total measurement. The method makes use of the measurement apparatus already in place and does not require additional sensing channels.

Abstract: An integrated system for real-time navigation assist during interventional radiological procedures utilizes a two-dimensional model of a catheter guide wire, obtained by performing image analysis on a fluoroscopic image in realtime, and a three-dimensional model of a patient's vascular system. The system backprojects the two-dimensional model into the three dimensional model and provides a three-dimensional display of the catheter in a patient's vascular system in real-time.

Abstract: An apparatus for reducing accumulated X-ray dosage during a fluoroscopic examination adaptively varies the time between exposures, X-ray beam strength, and beam extent and aim point during the course of the procedure in real-time. A temporal sequence image analyzer identifies a catheter in the fluoroscopic image and forms a prediction of its movement based on a time-series of fluoroscopic images. This prediction model is used to modulate the X-ray beam to produce a much smaller fluoroscopic image including only the area in the vicinity of the catheter tip. An output image synthesizer produces a useful output image by combining these stored sub-images.

Abstract: A variable depth triangulation ranging system is reconfigurable in real time in the sense that any two of the three performance measures, standoff distance, depth of field, and range resolution at a point within the depth of field, are selected by the user and the system geometrically reconfigures itself to provide the requested performance. The system is composed of a light beam emitting component such as a laser, a linear photodetector, and an imaging lens component. Any of these components has a fixed location and the other two are movable and positioned so that the Scheimpflug condition to guarantee blur-free imaging of reflected target returns is satisfied; the laser beam, a plane axis through the imaging lens component, and an image line through the photodetector all intersect at a common point. A scanner assembly is added to scan the laser beam along a line and over an area.

Abstract: Multiple light detection channels are introduced into a flying spot optical triangulation ranging system to increase the speed of acquiring range values. A laser beam is rapidly swept across a surface by a beam deflector. Each fiber optic channel can receive light only from a different point along a line at the intersection of the swept beam with the surface. The receiver channels are duplicated and separate detectors generate signal pulses at times that are a function of range to the surface. These are processed in parallel to calculate N range values per beam sweep, where N is the number of channels.

Abstract: High speed readout is achieved in a triangulation ranger by a coded aperture light detector which provides a direct digital representation of a range or height position. A light spot reflected from the surface is optically spread into a line segment so it can be shared among a number of light detection channels. The line of light falls on a coded aperture in front of a segmented fiber optic bundle and the light transmitted by each channel is led to a separate photomultiplier or solid state detector. Every coded channel is constructed to give one bit of the digital address of the range position, and a reference light value is obtained from another channel. Background and secondary reflections may be filtered out by focusing light scattered from the surface to a spot and passing it through a slit aperture oriented in the plane of triangulation before being spread to a line segment.

Abstract: A three-dimensional range camera, which produces a range map of the distances from a reference to each of M.times.N points in a scene, is modified to generate registered luminance and range images. The same sensor detects range and luminance variations. A planar pattern projector generates sequential presentations of time/space coded light rays which are projected onto the object. A linear array camera images the points of light on the object surface, and a processor analyzes one-dimensional scan signals to determine range. To detect luminance there is an additional presentation, either constant illumination or no artificial illumination, and the other scan signal yields luminance along the same strip of the scene.

Abstract: A non-contact sensor system measures distance from a reference plane to many remote points on the surface of an object. The set of points at which range is measured lie along a straight line (N points) or are distributed over a rectangular plane (M.times.N points). The system is comprised of a pattern generator to produce a 1.times.N array of time/space coded light rays, optionally a means such as a rotating mirror to sweep the coded light rays orthogonally by steps, a linear array camera to image subsets of the light rays incident on the object surface, and a high speed range processor to determine depth by analyzing one-dimensional scan signals. The range camera output is a one-dimensional profile or a two-dimensional area range map, typically for inspection and robotic vision applications.

Abstract: A method of nondestructive testing of the surface of an object using vapor condensation, such as sputtering, evaporation, or gas disassociation, to lay a thin solid film upon the surface of the object to be tested. The film is either highly reflective or highly absorptive. Portions of the solid film are then removed from the surface, for example, by abrasion while the remaining coating material is in a pattern depending on anomalies. The surface is then irradiated and inspected under light and the differential reflection between the remaining coating material and the surface itself enhances the visibility of the crack or other surface characteristic. The technique is especially useful for detecting very small cracks in cutting or grinding implements made of compacted material.

Abstract: A computationally efficient technique to determine weld puddle area and maximum width in real time from noisy measurements of the puddle trailing edge. Using the torch electrode as the origin, image intensities are sampled in radial directions, and potential pool edge points are extracted. The boundary data is prefiltered to remove extraneous points, and a least-squares algorithm is used to estimate the area and width of the elliptical puddle. The values are sent to a vision-based arc welding robot control system which regulates these pool parameters to assure full penetration welds. Angular orientation of the weld puddle is estimated in an analogous manner.

Abstract: The surface of the molten weld pool and surrounding workpiece area are floodlighted during an arc welding operation by a narrowband light source such as a laser in order to highlight the pool boundary and yield an image which is easily computer processed to give the pool perimeter. An arc welding torch has built-in optical systems, one to route laser energy via a coherent optical fiber bundle to exit optics on the torch to project two spots of light onto the trailing side edges of the pool, another to image the weld region which is relayed to a remote camera. The difference between reflectance values and direction on the pool and workpiece surfaces accounts for the enhanced image.

Abstract: A two-valued height-based image of an object on a support surface is acquired in one frame time of a raster scan, television-like camera. Two rotating sheets of light projected by synchronized sources intersect at the supporting surface and form a moving light bar. The image of light bars incident on a 3D object is discontinuous because of the parallax effect. The light bar illuminates and sweeps out a rectangular area in step with the electronic scan of the scene imager.