Abstract: Data bases of a first and second input output processor (IOP), which are primary and secondary slave IOPs, respectively, are sychronized, and communications by a master controller is made only to the first IOP. Each IOP is executing the same tasks utilizing their own clocking systems. A method for maintaining synchronization between the first and second IOP comprises the steps of transmitting a message addressed to the first IOP by the master controller. The first IOP receives the message for subsequent execution. Receipt of the message is acknowledged by a transmission back to the master controller the acknowledge message including a message number. The second IOP eavesdrops on the transmissions between the master controller and any of the IOPs on the network. Upon recognizing that the message is addressed to the corresponding first IOP and that the message is of a predetermined type, the second IOP receives the message for subsequent execution.

Abstract: A primary slave IOP, upon detecting an error, verifies the availability of a secondary slave IOP, and then sets an output control signal to indicate backup is requested. The primary slave IOP then takes itself out of being the primary. A secondary slave IOP, sensing that the output control signal from the other IOP has been set, assumes the roll of the primary slave IOP. A master controller, detecting an error with the primary slave IOP, interrogates the primary and secondary slave IOPs for a status input, and then arbitrates between the first and second IOP to determine the IOP that is to take on the primary role. Finally the master controller awards the more operational IOP the role of the primary slave IOP, thereby completing the failover operation.

Abstract: The apparatus for sensing pressure comprises a header, having at least one input port for receiving a substance under pressure. A substrate, having a wafer-like shape with a relatively large surface area in comparision to its thickness, includes at least one internal passage to couple the substance under pressure. A pressure sensing element is mounted onto the surface of the substrate over an exit port of the internal passage coupling the substance under pressure. The substrate is bonded to a surface of the header at extreme locations from a location in which the pressure sensing element is mounted. Thus isolation is provided for the pressure sensing element from unwanted stresses induced in the substrate.

Abstract: In a system for controlling or monitoring an object, wherein a position of the object must be determined, the system includes a first and second multispeed sensor, the first sensor having a speed of N and the second sensor having a speed of N-1. A method for determining the position of the object comprises the steps of obtaining position data as measured by the first and second multispeed sensor, respectively. A parameter, N.sub.A, a weighted difference between the obtained position data, is determined to ascertain whether a first or second case exists. If the first case exists, a first set of constants based on a first set of equations is generated; otherwise the first set of constants is generated based on a second set of equations. A second set of constants is then generated. Finally, the position of the object is determined by calculating the weighted average of the second constants, thereby obtaining the position of the object, utilizing the data provided by both sensors.

Abstract: A pressure sensor package, having a dual-in-line package (DIP) structure as commonly used in the semiconductor industry, comprises a first layer of predetermined material, having at least one internal passage for transmitting a fluid under pressure from a first surface of the first layer to a second surface of the first layer. A pressure sensitive element is bonded to the first surface of the first layer, and covers an exit from the first surface of the internal passage. A lead package, has a plurality of pins, each pin being perpendicular to the first surface of the first layer and placed along a first and second length of the first layer exterior to the pressure sensor package, and having a spacing conforming to the DIP configuration. Predetermined points of the pressure sensitive element are electrically connected to predetermined pins. A second layer of predetermined material is bonded to the first surface of the first layer providing an enclosed spaced for the pressure sensitive element.

Abstract: In a Traffic Alert and Collision Avoidance System (TCAS), response to interrogations can result in normal, multipath (image), and mixed multipath (potential image) tracks. The method for reducing the number of false tracks includes the steps of selecting a track to be updated from an existing track list. The selected track has the shortest measured range within the highest priority category track. A reply which has not yet been utilized is selected which has parameters which are within predetermined windows of the selected track parameters. (The predetermined windows are equal to or smaller than the windows for lower priority targets.) The selected track is updated using .alpha..beta..gamma. range squared filter, and the selected reply is marked as used. After all tracks are updated, the unused replies are tested to generate new tracks. Then all the tracks are examined to insure that predetermined track category criteria are met, otherwise the track is recategorized.

Abstract: In a process control system, having at least one process control unit which includes redundant equivalent controllers to reduce the impact of failure of the controllers in the process control unit, a technique is provided to guarantee that interruption of either the active (primary) controller or the backup (secondary) controller will not adversely effect the storage of data signals or the execution of commands by the process control unit. In the present invention, an information message or packet sent to the process control unit and, hence, to the active controller is forwarded to the backup controller before a response in the form of acknowledgement message is returned to the device issuing the information message or packet. The information message or packet is therefore stored in the same order in both the active controller and the backup controller and is executed in the same order by either controller.

Abstract: Aircraft/engine performance is determined by the method of the present invention, wherein the performance characteristics are defined by learned performance parameters. The method includes the steps of learning the performance parameters of the aircraft/engine combination, for a given flight, using previously learned performance parameters and current observations. Then, based on the performance parameters learned from the learning step, a prediction is made of the performance of the aircraft/engine combination for subsequent flights.

Abstract: A non-autonomous fiber optic network having the capability of monitoring optical data communications of said fiber optic network comprises an optical fiber cable which provides an optical medium (i.e., bus) for communicating optical signals. A bus controller controls the communications of optical information on the optical fiber cable. The bus controller also monitors the optical information outputted on the optical fiber cable, thereby verifying the integrity of the optical information transmitted to terminals connected to the optical fiber cable. An optical interface of the bus controller taps a percentage of power that is outputted onto the optical fiber bus and routes that signal to a receiver unit of the bus controller. The signal coupled back to the receiver unit is utilized by the bus controller to monitor the integrity of the transmitted data that is outputted on the optical fiber bus.

Abstract: In a flight management system (FMS) of an aircraft, there is included a speed generator that outputs a speed command for the aircraft in accordance with a preselected mode. The FMS further includes an apparatus performing a method for adjusting the speed to achieve a desired arrival time. The apparatus comprises a unit for generating a speed adjustment coefficient (KSA), a unit for calculating wind forecast error, and a unit for adjusting the command speed outputted from the speed generator. The adjusting unit utilizes the KSA, actual wind speed at the current aircraft position, and wind forecast error at the aircraft position. The speed adjustment compensates for the error in the wind forecast, in order to achieve the desired arrival-time.

Abstract: A dialogue system uses a three wire bus connecting a central station with a plurality of substations with two of the wires carrying an AC supply voltage and a third one of the wires carrying data by means of a closed loop of the AC carrying wires and the third wire. The central station uses a series connection of a data transmitter and a data receiver with the third data wire and each substation includes a data receiver in series with the data wire and a data transmitter between the data wire and both AC wires.

Abstract: In a digital data transmission system for transmitting a serial digital data stream between a first unit and a second unit connected to a first and second bus, respectively, a first apparatus interfaces the first bus to a transmission medium and a second apparatus interface the second bus to the transmission medium. The first and second unit and the first and second apparatus each have their own clock circuit. The first and second apparatus each comprise an encoder which outputs the serial digital data stream onto the transmission medium corresponding to serial data received from the first bus during a transmission period of the first bus. The encoder outputs the serial digital data stream onto the transmission medium in a predetermined format during a quiescent period of the first bus. A phase relationship of the serial data and the serial digital data stream outputted at the start of transmission between the quiescent period and the transmission period is established in a single bit time.

Abstract: A process control system has a network which includes a plurality of modules, each module performing a predetermined function. The modules include at least one history module, and at least one application module, the modules being linked via a medium such that each module can communicate with every other module of the network. The network interfaces with a control subsystem which interfaces with control elements of a plant process, the control elements having associated therewith process data. The process data includes data values and event data; the total data includes process data, data calculated from the process data, off-line data, and external data, the total data being stored in a storage device of the history module. A method for maintaining the total data comprises the steps of queuing messages requesting selected portions of the total data to be stored in said storage device.

Abstract: A method by which redundant network interface modules (NIMs) interconnecting the communication buses of two local area networks communicate with one another at predetermined time intervals over the communication buses of both networks. A first NIM of a redundant pair of NIMs is designated as the primary and a second NIM of the redundant pair is designated as the secondary. Contents of the information communicated between the NIMs over the communication bus of the first network includes the status of the transmitting NIMs ability to communicate with the second network and the information communicated between the NIMs over the communication bus of the second network includes the status of the transmitting NIM's ability to communicate with the first network. Based on the information exchanged, the failure of the NIMs to communicate as scheduled, and the internal status of each NIM as understood by that NIM, the NIMs decide when failover from the primary NIM to the secondary NIM occurs.

Abstract: The apparatus controls the positioning of a device in response to a commanded input signal, and comprises an element for moving the device in response to an error signal. A sensor component determines the actual position of the device, the sensor component outputting a primary signal and a derivative signal corresponding to the actual position and velocity of the device, respectively. A complementary filter system filters the primary signal and the derivative signal to generate a derived position signal, the derived position signal being combined with the commanded input signal thereby generating the error signal. The filtering results in effectively increasing the resolution of the sensor component thereby reducing the limit cycle caused by quantization of the sensor component.

Abstract: The fiber optic network of the present invention is within a structure having a plurality of bulkheads. The network comprises a plurality of terminal groups, each terminal group having at least one terminal. The network includes a reflective star coupler having m ports, m corresponding to the number of terminal groups. The terminal groups (having more than one terminal) include a 1.times.n transmissive coupler having 1 input port and n output ports, the input port being connected to the reflective star coupler via one of the m fiber optic cables, such that each bulkhead has a single fiber optic cable passing through the bulkhead.

Abstract: A communication system which includes a modem and a plurality of controllers has each controller connected to the modem by an interface apparatus, each controller and the modem complying with a predetermined protocol. The interface apparatus comprises a bus which provides a medium to transfer signals between the controllers and the modem. A first interface unit, which interfaces the modem to the bus, implements, a modem-associated multi-state state machine and responds to signals on the bus maintaining the predetermined protocol between the modem and the first interface unit. A plurality of second interface units interface a corresponding controller to the bus. Each second interface unit implements a controller-associated multi-state state machine which responds to signals on the bus and further responds to signals from the corresponding controller, each second interface unit maintaining the predetermined protocol between the second interface unit and the corresponding controller.

Abstract: A communication system which includes a modem and a plurality of controllers has each controller connected to the modem by an interface apparatus, each controller and the modem complying with a predetermined protocol. The interface apparatus comprises a first component, a bus, which provides a medium to transfer signals between the controllers and the modem. A second component provides an arbitration path between said controllers. A first interface unit, which interfaces the modem to the bus, implements a modem-associated multi-state state machine and responds to signals on the bus maintaining the predetermined protocol between the modem and the first interface unit. A plurality of second interface units interface a corresponding controller to the bus.

Abstract: The data processing system, has at least one memory unit operatively connected to a memory bus, and further has an input/output (I/O) bus controller for interfacing at least one peripheral device to the data processing system. The data processing system comprises a first bus which provides a first transmission medium between the peripheral device and the memory bus. A second bus, provides a second transmission medium between a CPU and the memory bus. A logic element, interposed between the first and second bus, and the memory bus, interfaces the first and second bus to the memory bus in response to request signals from the first and second bus.

Abstract: A process control system includes a processor which outputs command signals to a plurality of field devices via an interface unit. The interface unit comprises a primary output unit for outputting a first set of the command signals to the field devices in response to a first control signal. The first set of command signals are command signals for normal operation of the process control system. A secondary output unit outputs a second set of the command signals to the field devices in response to a second control signal. The second set of command signals are command signals for a failure mode of operation of the process control system. The second set of command signals are temporarily stored by the secondary output unit in order to respond quickly upon detection of an error.