Abstract: A device contained entirely within a tire for indicating when the pressure within the tire has fallen below a certain level. The device includes a releasable member within an enclosure; when the pressure falls below a certain level the member is released, whereupon it rolls around within the enclosure. The noise it makes while rolling around within the enclosure alerts the driver to the fact that the tire pressure has gotten low.

Abstract: An acoustic capacitor of minimum size and minimum susceptability to temperature-induced internal pressure change. The capacitor comprises an insulated container having an internal member of high heat capacity material surrounded by a porous thermally conductive material; the member acts as a heat sink, slowing the rate of change of pressure due to change in ambient temperature. The internal pressure that is built up due to temperature change is bled off by the same orifice that equilibrates the internal pressure to ambient atmospheric pressure.

Abstract: A method of inspecting the reinforcing members in prestressed concrete beams by generating a magnetic field close to the beam and measuring the field by means of a Hall effect sensor located between the pole pieces of the magnet. A partial or total break in a reinforcing member produces an anomaly in the magnetic field, which in turn registers as a voltage "spike" in the output of the Hall effect sensor. The method further includes a method for enhancing the data by substantially reducing or eliminating the effects of transverse reinforcing steel or support members located at the site of a break in the prestressed member.

Abstract: A method of inspecting the reinforcing members in prestressed concrete beams by generating a magnetic field close to the beam and measuring the field by means of a Hall effect sensor located between the pole pieces of the magnet. A partial or total break in a reinforcing member produces an anomaly in the magnetic field, which in turn registers as a voltage "spike" in the output of the Hall effect sensor. The method further includes a method for enhancing the data by substantially reducing or eliminating the effects of transverse reinforcing steel or support members located at the site of a break in the prestressed member.

Abstract: An electric blasting cap designed to be permanently disabled by the application of an external magnetic field. The cap contains a magnetic reed switch which creates an open circuit or a short circuit to prevent current from reaching the bridge wire. One embodiment of the switch is operated by a magnetizing field, the other is operated by a demagnetizing field.

Abstract: A method of testing the potential anti-misting and/or the drag reducing properties of a polymer modified fluid by testing its rheological behavior under increasing pressure. It has been found that the quantity of such fluids that can be pumped through a given system decreases as the pumping pressure is increased, thus giving an indication of the presence of the desired properties.

Abstract: A method of carrying a wheelchair externally of a vehicle without first folding the wheelchair. The wheelchair is placed so that its rear wheels rest against the rear of the vehicle; it is then lifted by a bumper-attached carrier, and the rear wheels roll up the rear bumper of the vehicle.

Abstract: A tire pump that is mounted on the rim, inside the tire. The pump is operated by centrifugal force when the tire rolls along the highway; it is designed to keep the air pressure within the tire at a constant, pre-set, level.

Abstract: A microcomputer-operated air brake control system for controlling the air brakes of a railroad car in a train is disclosed. The system includes a plurality of pressure sensors pneumatically connected to various points in the air brake system of the car and electrically connected to the input of the microcomputer. An ultrasonic height sensor for load compensation and detection of railroad derailments may also be connected to the input of the microcomputer. The output of the microcomputer is electrically connected to a plurality of electropneumatic valves for controlling the flow of compressed air to the brake cylinder of the car. The system also includes a radio transceiver electrically connected to the microcomputer for both receiving braking commands from a central control unit in the locomotive and transmitting feedback information from the air brake system back to the central control unit.

Abstract: A vehicle-follower control law for short headway automated guideway transit systems is implemented to provide an apparently optimal system in light of sensor accuracy, controller structure, and data transmission requirements. In particular, the spacing between two vehicles on a guideway is forced to an approximate optimal minimum value (S'.sub.min) by generating a signal (.epsilon.) which is the difference between the actual spacing (S) and the approximate optimal minimum spacing (S'.sub.min) and by driving the signal .epsilon. to zero according to a predetermined control law. In accordance with the invention, a constant headway or constant K-factor design can be employed in defining the control law. Embodiments for 0.5 second and 3 second headways are provided.

Abstract: A dual chamber personal flotation device which allows rebreathing into it. One of the chambers is for flotation only and is inflated with CO.sub.2 ; the other is for rebreathing, and is inflated with air. A tube located close to the wearer's mouth has a combination mouthpiece-shutoff valve on it which is designed to collect a minimum amount of water in it prior to being inserted in the wearer's mouth, thereby minimizing problems due to water ingestion during rebreathing. The chambers are independently inflatable in the event that either the size or the buoyancy has to be minimized in order to escape.

Abstract: A measurement system for determining the groundspeed of an aircraft during final approach and landing, by measuring at the aircraft the Doppler shift of a radio signal, and/or its modulation components, transmitted by a fixed ground station. The carrier signal is allowed to drift; it is provided with a modulated tone on the carrier having a frequency signature that identifies the direction and magnitude of this carrier frequency drift. In a second embodiment the Doppler cycles are not counted directly, but rather fixed increments of a cycle wavelength are measured; the time period of each segment is inverted to obtain a value proportional to the Doppler frequency.

Abstract: A simulated rail car identification system including a plurality of coded labels mounted at spaced apart locations on an endless conveyor. The conveyor produces horizontal movement of the labels sequentially through a zone viewed by an optical scanner. A control system monitors and controls operation of the endless conveyor and generates block signals responsive to the relative position thereof and wheel signals responsive to the entry of individual labels into the viewing zone. Processing and decoding of the information retained by the moving labels is accomplished by a data processor that receives the output of the scanner and the block and wheel signals from the control system. The effectiveness of the scanner and processor are determined by comparing their output to the data programmed into the control system and encoded on the moving labels.

Abstract: Portable apparatus for use in measuring vertical deviation of the surface of a rail from a reference plane. The measuring device includes a pair of guide beams and a hand-powered carriage which move along the beams. A sensor, which follows undulations resulting from rail wear, is mounted on the carriage and is coupled to the pen of a recorder.

Abstract: The measurement of small differential temperatures over a wide range of absolute temperatures is accomplished by cyclically switching the excitation polarity to a bridge circuit including the temperature sensors. Additionally, the measuring circuitry includes a differential-differential amplifier configuration and a pair of compensating conductors in the cable to each sensor to achieve equal resistance in each excitation path.

Abstract: The invention is a system for measuring the gage of railroad tracks and includes a pair of sensor probes mounted a fixed distance apart on a wheeled vehicle traveling along two rails and each located in positions horizontally adjacent to one of the rails. Each of the probes retains spaced apart first and second collimated light sources that direct first and second light beams at incident angles against the inner surface of the adjacent rail head at points five-eighths of an inch from the top surface thereof. After reflection from the rail head the first and second beams produce images in an optical receiver also retained by the probe. A detector produces an output dependent upon the spacing between the first and second beam image centers which is in turn dependent upon the distance between the probe and the adjacent rail head.

Abstract: A gas sensor unit designed to indicate the presence of hydrocarbon vapors but be insensitive to carbon monoxide. The unit comprises two TGS sensors, one covered by a semi-permeable membrane and the other uncovered; the uncovered sensor responds to both crude oil and carbon monoxide, the covered sensor responds only to carbon monoxide. In one embodiment, the two sensors are connected in series; the total response of both sensors and the difference in response between the two sensors are measured, and changes in the parameters indicate the presence of an oil spill. In another embodiment, each sensor's output is compared with its reference voltage; if the uncovered sensor has an output that is higher than its reference while the covered one does not, the presence of an oil spill is indicated.

Abstract: A laterally movable ultrasound transducer, comprising the sensor of a rail fault detection device, is automatically centered on the rail as the detection device moves along the rail. The sensor includes a pair of ultrasound receiving transducers positioned to either side of a transducer which generates and receives ultrasonic energy. Signals provided by the receiving transducers are compared and any difference therebetween employed to control the lateral position of the sensor with respect to the rail.

Abstract: A method of detoxifying organotin-containing paint residues that are sandblasted from the bottom of a ship's hull comprising cleaving the tincarbon bond by application of an oxidizing agent, preferably nitric acid.

Abstract: Automated gain control in rail flaw detection which includes attenuation of echoes from rails pulsed with a burst of sonic energy, comparing said attenuated signals over discrete intervals, and reducing or increasing said attenuation in response thereto to develop a uniform signal from which an evaluation of flaw indicating echoes can be obtained.