Abstract: A shock absorbing pad, preferably for the interior of a vehicle, comprising a series of interconnected fluid reservoirs in the form of spheres partially filled with a fluid. Below a certain level of impact the shock is absorbed as the fluid is forced from one sphere into one or more of the other spheres. Above that level the spheres rupture, thereby absorbing the shock.

Abstract: An emulator for a radar set which utilizes a conventional personal computer rather than specialized equipment. The emulator comprises a printed circuit board and a program for operation of the computer. The computer calculates the data for one antenna scan and stores it in a memory bank on the board; as this is being read out as radar video which is displayed on the screen, the computer calculates the data for the next scan and stores it in a second memory bank on the board. In this way a continuous series of scans is presented without requiring the extensive computational power that would be required to display a scan as it is being calculated.

Abstract: An asymmetric set of pre-swirl vanes (stators) and a specially matched propeller for use on an inclined shaft. The propeller is designed by considering the mutual interaction of the propeller on the vanes and the vanes on the propeller. The propulsor unit provides the following:1. increased propulsion efficiency due to the reduced rotational (swirl) and axial kinetic energy losses in the propulsor's slipstream;2. reduction or elimination of propeller cavitation;3. reduction or elimination of unsteady propulsor forces as well as propulsor-induced hull vibrations.A unique feature of the present invention is that a prior art flat faced commercially available propeller can be modified to match the vane flow field for optimum propulsor performance. The use of commercially available propellers reduces the installation or hardware cost significantly and allows the propeller to be repaired easily if damaged.

Abstract: A device for calculating the center of gravity (CG) and moments of inertia of a vehicle. The vehicle is driven onto the device and the height of its center of gravity is determined by hanging weights on the device to displace the vehicle's CG from its position without the weights; the height of the CG is then calculated by a simple mathematical formula. The pitch moment of inertia is calculated by aligning its axis perpendicular to the axis of the pivots and allowing the vehicle to swing, then calculating the moment of inertia by another mathematical formula. The roll moment of inertia is calculated by rotating the vehicle 90 degrees, letting it swing, and then using a slighly different formula. The yaw moment of inertia is calculated by lowering the device to the ground and causing the vehicle to oscillate about a pivot point, then calculating the yaw moment of inertia by means of another mathematical formula.

Abstract: A smoke generator which generates cold smoke having the buoyant properties of smoke produced by a fire. The density of the smoke can be varied to simulate any desired fire plume temperature by adding helium or other lighter than air gas to it. This produces a smoke which rises and spreads just like the smoke from a fire but without requiring that a fire be used to produce the smoke.

Abstract: A radiotelephone and a radar transponder are interconnected in such a manner as to establish a VHF communications link via the radiotelephone in response to interrogation of the radar transponder. The radar transponder will ordinarily be periodically enabled and will transmit a code which partially identifies the transmission source in response to interrogation when enabled. The radiotelephone will also be periodically enabled so as to transmit a more complete identifying code and requests and coded information received via the VHF communications link will be decoded and displayed.

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 device for protecting a fifth wheel in case the vehicle to which it is attached spins out or backs up for a considerable distance. The device comprises a pair of rods which project rearwardly and downwardly from the bracket mounted on the vehicle; when the vehicle backs up or spins out and the fifth wheel is moved through a horizontal arc toward the rear of the vehicle, its tongue rides up onto one of the rods and is lifted off the ground. When it is out of contact with the ground it can no longer be moved toward the vehicle.

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 digital Moving Target Indicator (MTI) radar system for rejection of low velocity "clutter" by utilizing techniques to identify those radar echo returns from targets having radial velocities lower than fixed predetermined values. For digital MTI radars that have a response which is a periodic function of the radar's Pulse Repetition Frequency (PRF) and doppler frequency shift of the received radar signal relationships exist whereby (a) optimum target velocities which correspond to the maximum canceler gain can be calculated from the radar's PRF; (b) the canceler response can be expressed in terms of a periodic canceler response function which incorporates the ratio of the actual target velocity to the optimum target velocity; and, (c) the output amplitude from the canceler can be determined from the input amplitude to the canceler produced by the MTI receiver's coherent phase detector and the periodic canceler response function.

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 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 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.