Abstract: A miscomparison between a channel's configuration data base and a voted system configuration data base in a redundant channel system having identically operating, frame synchronous channels triggers autoequalization of the channel's historical signal data bases in a hierarchical, chronological manner with that of a correctly operating channel. After equalization, symmetrization of the channel's configuration data base with that of the system permits upgrading of the previously degraded channel to full redundancy. An externally provided equalization command, e.g., manually actuated, can also trigger equalization.

Abstract: An elevator monitoring apparatus and method are disclosed in which an elevator is modeled as operating in a closed loop chain of normal operating states from which message initiating transitions to abnormal states causes the latest to occur of a selected number of monitored events are recovered from a storage buffer as an aid to an analysis of an abnormal state. Door and motion closed loop chain state machines are disclosed as effective tools for abnormal event detection, especially for a state machine approach implemented within an elevator controller.

Abstract: A capacitance pressure measuring circuit includes a pressure sensitive capacitive transducer and a reference capacitor that are configured in a differential mode to alternately charge and discharge in response to square wave signals. An integrator receives signals from the capacitors and outputs two voltage levels. These voltage levels are provided to a synchronous clock driven selectable sample and hold stage and then to a differential amplifier. The amplifier provides a linear voltage signal proportional to the change in the difference in capacitance of the transducer divided by the capacitance of the integrator.

Abstract: The insulation of a plurality of grounded wires may be tested subsequent to fabrication and prior to spooling by use of a corresponding plurality of modular circuit boards installed in an AC/DC continuity tester having enhanced isolation features including on board DC power supplies and clock generators. A signal processor gathers fault data from each board and provides a fault count signal for each wire which may be printed out on a printer within the tester. Isolation between channels is enhanced by using a simple and compact test head having a plurality of rollers or sheaves separated by teflon spacers, all mounted on a common rod.

Abstract: A method and apparatus is disclosed for winding an advancing strand onto a spool having a barrel and a pair of end flanges utilizing a strand traverse guide reciprocated relative to the spool at a linear speed proportional to the relative rotational velocity of the spool. The spool may have flat end pieces or tapered ends. The barrel of the spool may be cylindrical or tapered. The end limits of reciprocation of the strand guide are established in relation to the spool base and are determined based on the rotational speed of the spool, the linear speed of the strand and the known geometry of the spool.

Abstract: Apparatus and method is disclosed for determining position with light by providing input light at an input light port of an optical cavity having a variable length dimension and detecting light which has traversed the variable length dimension at an output light port of the optical cavity and determining the present length of the variable length dimension using the detected light as a measure.

Abstract: The power required for a helicopter to hover is generated (14, 82) as the ratio of current operating power in forward flight (12, 77) determined (10, 73) from data relating operating power in forward flight to power required for hover for the aircraft. The power required to hover is compared (18, 83) with the maximum power available developed (16, FIG. 2; FIG. 3) by an engine model algorithm utilizing actual engine parameters. The comparison of maximum power to power required for hover is utilized to provide an indication (22) to the pilot. The viability of the indication is indicated by a "ready" indication (26).

Abstract: An angular velocity sensor utilizing the Coriolis effect on a fluid jet employs a metal diaphragm impulse jet pump with no valves to reduce temperature sensitivity. The pump anvil, the nozzle block and the sensor plug may all be fabricated of the same material to further reduce temperature sensitivity. The thickness of the sensing elements is selected to reduce temperature sensitivity still further.

Abstract: A high fault coverage, instruction modeled self-test for a signal processor in a user environment is disclosed. The self-test executes a sequence of sub-tests and issues a state transition signal upon the execution of each sub-test. The self-test may be combined with a watchdog activity monitor (WAM) which provides a test-failure signal in the presence of a counted number of state transitions not agreeing with an expected number. An independent measure of time may be provided in the WAM to increase fault coverage by checking the processor's clock. Additionally, redundant processor systems are protected from inadvertent unsevering of a severed processor using a unique unsever arming technique and apparatus.

Abstract: Method and apparatus for correcting reversal points for a traverse for guiding a strand from a reference wheel onto a spool utilize signals indicative of the angular velocity of both a reference wheel and the spool to determine first the actual spool radius at a reference point away from the spool's flanges, then determining the proper spool radius at each reversal point and then determining the actual spool radius at each reversal point. The actual spool radius and the proper spool radius at each reversal point are compared and if a difference greater than a predetermined amount is present, the reversal point is altered by a selected incremental amount.

Abstract: A data hub for facilitating and effecting data transfers between signal processors with high efficiency is disclosed. The data hub receives low priority data transfer instructions from a master CPU and is capable of transferring such low priority data between processors without imposing significant overhead burdens on either the data source or destination. The hub may have the further capability of asynchronously receiving intermediate priority data transfers, storing the received data and transferring it to a destination unit before any further low priority transfers are effected. The hub may have the further capability of asynchronously receiving high priority transfer requests which are effected by the hub before both intermediate and low priority transfers. The hub may be used as a keystone building block for use in linking signal processors.

Abstract: A printed circuit board heat sink retainer is disclosed comprising a mating pair of sawtoothed bars with slidably engaging teeth. The bars are laterally spread apart and held by a forcing device, which may be a screw or a spring, in order to push against and hold a heat sink in a channel. The distance between successive teeth may be constant in both bars or may be constant in one bar and may decrease in a direction toward the forcing device in the second bar.

Abstract: An angular velocity sensor utilizing the Coriolis effect on a fluid jet employs increased spacing between the sensing elements to increase the scale factor and to reduce flow disturbances. A metal diaphragm pump is utilized to improve the ability to control the flow rate. Flow disturbances are further reduced by using a single, symmetrical central flowhole, eliminating curtain holes, and providing only two discharge paths oriented 180.degree. apart.

Abstract: A Remote Subsystem for monitoring a large number of parameters relating to operating equipment at a remote site is disclosed. A monitoring system having a plurality of local service offices each reporting to a central office and each having a plurality of remote subsystems at remote sites reporting to it is also disclosed. Each remote subsystem reports only a first alarm condition detected for a particular unit of equipment to its local office and reports the unit back in a normal operating condition only after all detected alarm conditions have returned to a non alarm status. In this way, the local and central offices are not inundated with information of little value. Each remote subsystem also monitors conditions that are indicative of impending alarm conditions in order to alert local and central service offices of developing problems in the field. Similarly, each remote system monitors and accumulates miscellaneous data useful for a variety of monitoring purposes.

Abstract: Apparatus and method for controlling a variable speed wind turbine-generator at improved efficiencies is disclosed. The method and apparatus of the invention control the rotor tip speed below the limiting torque of the wind turbine at a selected constant velocity ratio with respect to wind speed and, above the limiting torque, control the rotor tip speed at speeds greater than those dictated by the constant velocity ratio up to a speed or power limit. This may be accomplished by controlling tip speed above the point where limiting torque is attainable to maintain optimal wind turbine performance along the performance envelope.

Abstract: A piezoelectric phase modulator for a fiber optic sensor is disclosed. The disclosed modulator is capable of relatively large amplitude mechanical vibrations, i.e., having a large converse piezoelectric effect, while at the same time having a relatively predictable and well-behaved direct piezoelectric effect. This result is accomplished by bonding a relatively active piezoelectric material, such as PZT, to a relatively stable piezoelectric material, such as quartz. An optical fiber may then be bonded to the relatively stable material, or to a structure attached thereto, as part of a fiber optic sensor loop. Excitation of the relatively active piezoelectric material will then produce a mechanical vibration in the relatively stable material and in the attached fiber comparable in magnitude to that experienced by the active material. Several embodiments of the invention are shown which are illustrative of devices which may be made according to the teachings disclosed.

Abstract: An active Q-switch integral laser cartridge is made of an acoustic transmitting body having a photoelastic laser medium in a part thereof for propagating and coupling both optical and acoustic waves. The photoelastic laser medium and the acoustic transmitting body may be made of substantially the same or similar base material.

Abstract: A variable speed wind turbine is controlled in a way which avoids the turbine lingering at a critical speed which would otherwise tend to cause excessive vibration. The disclosed method and apparatus increases speed at a selected rate with respect to generator output power except in the vicinity of the critical speed. The selected rate is changed in the vicinity of the critical speed to a different rate which is selected slower in the selected embodiment, to avoid commanding the critical speed. After the output power increases or decreases beyond the critical point, a deliberate discontinuity in the speed command signal is induced. A rapid speed change through the critical speed is accompanied by a corresponding power output change.

Abstract: A synchronizer for use in synchronizing individual signal processors in a multi-channel system is disclosed. Each synchronizer has a counter for counting its associated processor's clock pulses and, upon reaching a selected count, providing a counter frame output signal at an output thereof for use by each of the other synchronizers in the system. Each synchronizer has a voter responsive to counter output signals from each of the other synchronizers, and from itself as well, at input ports thereof. Each synchronizer's voter provides a frame sync (macro sync) pulse in each counter frame after receiving a selected number of counter frame output signals from any of the synchronizers in the system.

Abstract: A variable speed wind turbine includes a frequency converter which converts variable frequency AC from a turbine driven AC generator to fixed frequency AC for delivery to a power grid. The frequency converter is typically an electronic cycloconverter or rectifier-inverter and is also used to control the power flow from the AC generator to the grid which thereby controls the air gap torque between the generator stator and rotor. The turbine speed is maneuvered to increase efficiency by precisely controlling the air gap torque according to a schedule defining sensed generator speed versus sensed generated power.