Abstract: A method and apparatus are provided for producing green salt (UF.sub.4) from uranium-bearing metal pieces. The uranium-bearing metal pieces are dissolved in a first aqueous solution containing hydrochloric acid and between 0.5% and 5% fluoboric acid to provide a second aqueous solution which includes uranium (U.sup.+4), chlorine ions (Cl.sup.-) and hydrochloric and fluoboric acids. Hydrofluoric acid is added to the second aqueous solution to precipitate green salt out of that solution and provide a third aqueous solution which contains hydrochloric acid. The green salt is then separated from the third aqueous solution.

Abstract: A scintillation camera having scintillation material which emits light in response to absorbed radiation, an array of photodetectors for detecting the emitted light, and a segmented light pipe which conducts the emitted light to the photodetectors. The light pipe includes a plurality of segments which intersect with adjacent segments at an angle and define planar faces which are optically coupled to the photodetectors.

Abstract: A compound collimator for use in a radionuclide emission tomography camera to image a region of an object, including a collimator structure having a number of collimator elements arranged in at least two sections to define a different tomographic field of view boundary for each section. Each boundary encompasses a different portion of the region and the sections in combination establish a different imaging sensitivity for each portion. At least one of the boundaries encompasses the entire region to be imaged.

Abstract: A beacon navigation system for a vehicle including a plurality of navigation beacons distributed about a premises through which the vehicle is to navigate, and a detector assembly for sensing a beacon and for resolving the azimuthal angle between the beacon and the vehicle. The system further includes an element for defining an optimum azimuthal angle between that beacon and the vehicle, and a device for determining the difference between the resolved angle and the optimum angle to represent the deviation of the vehicle from a designated path. A method of establishing navigational paths among navigation nodes proximate beacons is also disclosed.

Abstract: A mapping system and method which establish a number of navigation nodes and paths among them for a vehicle in an environment to be navigated by directing the vehicle to a selected location in the environment, designating that location as a first node, identifying the initial direction of a path to a second node such as by locating a navigation beacon proximate the second node, and moving the vehicle in the initial direction from the first node while measuring distance travelled along the path to the second node. This system and method further include defining the second node by at least the distance travelled along the path and by the initial path direction.

Abstract: A position locating system for a vehicle such as a mobile robot which includes a multisector sensor for sensing the coded signal emitted by a beacon. There are means responsive to the sensor for generating a code data signal representative of the coded signal and means responsive to the sensor sectors for generating an angle data signal representative of the angle from sensor to the beacon and at least one of the azimuthal and altitude dimensions.

Abstract: This invention features a mobile robot having a body which has an azimuthal angle that is optimally fixed in space and provides the basic reference for the robot to the outside world. The robot further includes a drive system having wheels for enabling movement of the robot, a synchronous steering mechanism which turns the wheels independently of the body, and a head which turns with the wheels. The robot further includes memory for storing the azimuthal angle of the body, a detector assembly disposed in the head for sensing a navigation beacon and resolving an angular deviation between the head and the beacon, and an element for incrementing the stored azimuthal angle by that angular deviation. A system for enabling orientation adjustment is also disclosed.

Abstract: Pieces of metal are joined with silver material in a two-stage heating process. In one application, a brazed porous coating of metal particles on a metal substrate of a device is formed by interposing a silver material between the substrate and the particles, and placing the particles onto the substrate. The device is heated to a first temperature slightly below the melting point of the silver material, then briefly heated to a second temperature above 1100.degree. C. to rapidly melt the silver material to wet the particles and substrate and to generate alloying among the silver material, the particles, and the substrate. The device is allowed to cool to solidify the alloy and unite the particles and substrate to form a porous coating on the device. Also disclosed are a prosthetic device having a metal shaft for insertion into a bone canal, and a porous coating of metal particles brazed to the metal shaft by a silver material.

Abstract: Grinding disk and method for finishing a workpiece having irregularities thereon, having a highly flexible inner portion and an outer annular face portion having sufficient flexibility to enable such annular portion to be substantially deformed by the irregularities of said workpiece upon contact therewith.

Abstract: A high-speed, limited-shift signal processor for quantized weighting of an input signal, which receives the input signal and delays is to provide a plurality of delay outputs and selects a number of the delay outputs to be modified by limited shifting of their place values. The limited-shift signal processor generates at least one weighted value from each delay output, including shifting the digit positions of each selected delay output to shift its place value, and sums each of the place-value-shifted delay outputs to obtain a weighted sum signal of the input signal.

Abstract: A conversion apparatus for quantizing a set of weights for a weighted sum signal processing system, including a predetermined number of conversion arrays operable in succession and a transfer and monitor circuit. Each conversion array stores a plurality of values to be converted, quantizes the values to be converted to produce a set of discrete values and a set of error values and replaces the contents of the means for storing with the set of discrete values. Each conversion array also combines the set of error values with a set of interpolator weights to form a transformed error set. The transfer and monitor circuit successively combines the transformed error set most recently formed with the contents of a successive conversion array, monitors the successively produced sets of error values, and halts the successive conversions and combinations when a predetermined condition is satisfied. The invention also features a method of quantizing such a set of weights.

Abstract: An elliptical reflector illumination system for inspection of printed wiring boards including an elliptical reflector element for mounting above the board to be inspected with a region of the board generally at a first elliptical focus of the reflector element. There is a light source mounted generally at a second elliptical focus of the elliptical reflector element for illuminating substantially all facets of the region of the board at the first focus. One or more detectors are provided for sensing light reflected from the illuminated facets of at least a portion of the illuminated region of the board at the first focus.

Abstract: An adjustable biopsy paddle for compressing tissue to be examined and assisting localization of a needle relative to a nonpalpable lesion, the paddle including a locator plate having a plurality of tissue access holes of generally uniform diameter and of generally uniform spacing in a first direction, typically the lateral direction. The paddle further includes a guide for permitting movement of the plate in the first direction for a distance of at least half the distance of the spacing, and a bracket for slidably supporting the plate.

Abstract: A method and apparatus are provided for producing uranyl peroxide (UO.sub.4.2H.sub.2 O) from uranium-bearing metal pieces. The uranium-bearing metal pieces are dissolved in a first aqueous solution containing nitric acid and between 0.5% and 5.0% fluoboric acid to provide a second aqueous solution which includes uranyl ions (UO.sub.2.sup.+2) and nitric and fluoboric acids. Hydrogen peroxide is added to the second aqueous solution to precipitate uranyl peroxide out of that solution and provide a third aqueous solution which contains nitric and fluoboric acids. The uranyl peroxide is then separated from the third aqueous solution.

Abstract: An apparatus and method for uniquely detecting pits on a smooth surface by irradiating an area of the surface; separately sensing radiation scattered from the surface in the near-specular region indicative of a pit and in the far-specular region indicative of a flaw and producing signals representative thereof; normalizing the near-specular signal with respect to the far-specular signal to indicate a pit; and discriminating the near-specular components of the normalized signal representative of surface pits.

Abstract: An elongated handle having an interior coil spring and a flexible jacket positioned over the spring is screwed into a terminal portion of a conventional automobile door lock actuation mechanism. The application of lateral forces to the handle by a thief will cause the handle to be bent owing to its high lateral compliance in directions transverse to the longitudinal axis of the handle, to prevent a thin, manually actuated tool from grasping the handle to a sufficient extent to enable the lock to be "popped" open.

Abstract: A surface inspection defect detection and confirmation technique in which a beam of radiation is directed at the surface to be inspected; the radiation scattered from the surface is separately sensed in the near-specular region indicative of a pit and in the far-specular region indicative of a flaw, the near-specular region signal and far-specular region signal are normalized, the near-specular component is discriminated, and the flaw signal is indicated as being a defect and not contamination when there is coincidence between the pit signal and flaw signal.

Abstract: An airflow directional vane for a heatsink carrying a plurality of heat-dissipating elements which extend from a base including a vane element which is mounted directly to at least one of the heat-dissipating elements of the heatsink. The vane element extends outwardly from the heatsink to direct airflow across the heatsink through the heat-dissipating elements.

Abstract: Digitizer pen caddy configured to rest upon a digitizer pad for inputting data into a computer by sensing pressure applied to selected areas of the pad by the digitzer pen, the caddy including a light transmissive resilient base member, and a digitizer pen gripping grommet within the resilient base member, the resiliency of the base member being high enough to permit sufficient displacemt of the pen toward the digitizer pad when the base member is pressed by the hand of an operator. The displacement however, is limited to protect the digitizer pad from damage.

Abstract: A delayed actuator mechanism with visco-elastic timer is provided including a support section and an actuator section mounted to the support section. A compression spring biases the actuator section in a first state and permits the actuator section to be selectively switched to a second state. In that state a cocked torsion spring urges a detent carried by the actuator into engagement with a shoulder of the support section to restrain the actuator section in the second state. A visco-elastic delay mechanism gradually relaxes the torsion spring until the compression spring overcomes the detent shoulder restraint to abruptly switch the actuator section to the first state.