Abstract: A micromachined integrated opto-thermal sensor having a rapidly intensity varying or pulsing light source, an interference filter, shadow masking or reflective blocking of light from thermal sensors, or differential operation, a gas cavity into which the detected gas can flow into via a channel or filter, and a thermal detector elements to sense the heating of the gas caused by the absorption of light at a particular wavelength by the specific gas to be detected. Another version of the sensor is one with a dual cavity. One cavity contains the gas to be detected and the other cavity is sealed from the ambient environment and contains no gas. Signals from the detectors from the cavities are subtracted from each other resulting in the elimination of a fixed signal due to radiation impinging the detectors. A ratio of the signal from the detectors may be calculated for determining a presence of gas or fluid. The detector may have only a single cavity with two groups of thermal sensors.

Abstract: An automatic tuner for control systems that produces, as output values, parameters of an arbitrary controller. The controller is in a control loop so that its output effects changes in actuators and regulates a physical process. The controller has either linear or nonlinear controller components, or a combination of both. The tuner has a nonlinear approximator that has been optimized off-line. The off-line optimization is done without supervised learning so that desired outputs of the nonlinear approximator do not need to be available, and separate optimization to generate the desired outputs is not necessary. The off-line optimization can also rely on arbitrary criteria. Such optimization ensures robustness of generated controller parameters so that the input process characteristics do not need to be highly accurate. The inputs to the nonlinear approximator consist of two sets of input parameters, either of which may be empty. A first set of input parameters can relate to process characteristics.

Abstract: A fiber optic sensor coil is wound from a length of optical fiber with the mid-point of the optical fiber at the mid-point of the innermost layer of the coil and subsequent layers of the coil each have alternating turns of the two sections of the fiber emanating from the mid-point. The layers of alternating turns are formed by first winding a portion of one segment in such a fashion that adjacent turns are spaced apart by a distance equivalent to the diameter of the optical fiber. The layer is completed by winding a portion of the other segment such that the turns of the other segment are disposed between adjacent turns of the one segment. The number of turns in adjacent layers are unequal such that the turns of a next layer are arranged in grooves formed between two adjacent turns of optical fiber in the previous layer.

Abstract: A mesopump having a plurality of elementary cells and a method of pumping fluids using the mesopump. The cells each have a body forming a cavity having upper and lower electrodes with curved surfaces facing the other electrode. Electrical connections selectively energize the electrodes. A bistable diaphragm is mounted with its major portion located in the cavity between the electrodes so that the diaphragm deflects toward the upper or lower surfaces to conform thereto. A lateral conduit is located at at least one end of the body for fluid communication with the cavity. The lateral conduits are operably connected to a portion of the diaphragm mounted in the body and are opened and closed by movement of the diaphragm. A vertical conduit on at least one curved surface controls flow of fluid by movement of the diaphragm into and out of contact with the vertical conduit.

Abstract: An apparatus for identifying the structure and estimating the parameters in the structure of a controlled system is described. The apparatus uses a structure identifier, in a preferred embodiment, employing a neural network, to match the relationship of the system inputs and outputs to a mathematical relation. This identified structure is communicated to a parameter estimator. The parameter estimator may employ a neural network to give an initial parameter vector which can be used to generate, iteratively, better parameter estimates. This increases the efficacy of the parameter estimator. The apparatus can be inserted into controllers for various systems to improve performance. Using a neural network for parameter estimation as shown can be generalized to any nonlinear optimization problem.

Abstract: A direct adaptive fuzzy controller having an adaptation mechanism that modifies the locations of output membership functions to improve performance of the fuzzy controller. The controller has a fuzzy rule base that has a different or unique output membership function for each fuzzy rule. The adaptation mechanism modifies the location of the output membership functions in response to the performance of the controller system, to continuously improve its performance. The controller is a feedback mechanism that functions not only using measured outputs of the process controlled, but has feedforward compensation that causes the controller to anticipate feedback due to measured disturbances or other parameters of the process.

Abstract: A cable operated switching mechanism is provided with a positive locking method that latches a cam structure in place after the cable is pulled by an operator and does not permit the cam structure to return to its normal operating position until manual intervention is used to push a reset plunger. The cable operated switching mechanism provides this positive stop by incorporating a tab on a latching device which is associated with the reset plunger and moves with it when a reset button is pushed by an operator. The tab of the latching device slides along a first surface of the cam structure until the cable is pulled to activate the mechanism. Then, under the influence of a spring, the latching device moves upward to cause the tab to move into a blocking position relative to a second surface of the cam structure. The prevents the cam structure from moving from its actuated position to its normal operating position until a reset button is pushed.

Abstract: A method of packaging a fiber optic coupler formed of a plurality of optical fibers having a coupled region at which electromagnetic waves are coupled therebetween and at least one lead portion extending from the coupled region. A protective body is provided having a receiving space therein. The coupled region and a portion of the at least one lead portion are positioned within the receiving space. A slack in the at least one lead portion is created by affixing two points of the portion of the at least one lead portion to said protective body. The slack is created between the two points.

Abstract: A touch mode electrostatic actuator and method of making the same, having first and second electrode driven surfaces positioned to move between a spaced apart relationship and a contact relationship when dielectric layer on each of the first and second electrode surfaces is subjected to a source of electrical potential to selectively actuate and discharge the dielectric layers to cause the movement between the relationships. The electrostatic actuators of this invention includes a hydrophobic layer for preventing absorption of water thereon, the hydrophobic layers being adapted to cause condensed water to form drops and prevent formation of a continuous water layer. The hydrophobic layer may be a coating on a hydrophilic actuator or, alternatively, may be made entirely from a hydrophobic material.

Abstract: A delay locked loop, temperature independent, wide range frequency clock multiplier that outputs a clock signal that has a frequency that is a multiple of the frequency of the input clock signal. The multiplier does not use any phase-locked circuitry. It has adjustable delay lines or cells that are cascaded and have outputs to a multiple input exclusive OR gate. The exclusive OR gate outputs the multiplied frequency signal. A delay controller outputs a signal to each of the delay lines or cells for setting the amount of delay in each line or cell. A delay monitor has inputs from the exclusive OR gate output and the delay controller output. The delay monitor outputs signals to the delay controller which has a phase differentiator. The delay controller output is such to maintain a particular duty cycle on the waveform of the multiplied frequency signal output from the exclusive OR gate.

Abstract: A telemetry transmitter having a dielectric resonator for frequency stabilization, a frequency or phase shift keying modulator and a high efficiency power amplifier. The transmitter can be implemented on gallium arsenide or other kinds of substrates The transmitter is of monolithic microwave integrated circuit (MMIC) technology. The transmitter may obtain its power from a power supply of a local or an associated system, thus not needing an integral power supply of its own.

Abstract: A micromechnical sensor having a polysilicon beam that is an integral part of the diaphragm resulting in a frequency of the beam that is a direct result of the pressure applied to the external surface of the diaphragm. Fabrication of this resonant microbeam sensor has no backside wafer processing, and involves a process and layout independent of wafer thickness for high yield and robustness. Both the diaphragm and resonant beam are formed from polysilicon. The sensor may have more than one resonant beam. The sensor beam or beams may be driven and sensed by electrical or optical mechanisms. For stress isolation, the sensor may be situated on a cantilevered single crystal silicon paddle. The sensor may be recessed on the isolating die for non-interfering interfacing with optical or electrical devices. The sensor die may be circular for ease in mounting with fiber optic components.

Abstract: A method and apparatus for exciting and controlling a switched reluctance motor having pulse duration modulated current provided to the windings of the motor. A start signal determined by a rotor position sensor, charges a capacitor. The capacitor is discharged according to an error signal that indicates the difference between a desired magnitude of a parameter, such as torque or speed, and the actual magnitude. A comparator puts out a pulse having a duration which is the same as the time that the capacitor has a charge. The pulse from the comparator turns on a switch connected to respective windings of the motor and provides a current pulse that has a duration equivalent to that of the pulse from the comparator. This sequence is repeated for all of the windings of the motor so as to maintain its speed or torque at the desired magnitude.

Abstract: A silicon accelerometer includes a plurality of silicon layers. The silicon layers form first and second silicon beams supported by flexure members. An acceleration responsive silicon mass is arranged to bend the flexure members in response to accelerations. The silicon beams are vibrated in vacuum chambers and gas damping is provided for the acceleration responsive mass and the flexure members. A sensor is provided for sensing vibration of the first and second silicon beams.

Abstract: A backscatter or secondary wave error reducer for an interferometric fiber optic gyroscope having at least one phase modulator for receiving a square wave bias phase modulation signal and a sine wave carrier suppression modulation signal. The amplitude of the carrier suppression modulation signal is sufficient to greatly reduce the interference between two sets of backscattered or secondary waves of light originating in the Sagnac loop of the gyroscope. Reduction or elimination of the interference of the two sets of secondary waves reduces or eliminates the secondary wave induced rotation rate sensing error. The frequency of the carrier suppression signal is near or equal to an even harmonic of the proper frequency of the Sagnac loop to reduce the sinusoidal or periodic rotation rate sensing error caused by the carrier suppression modulation signal.

Abstract: A device for eliminating coherent pickup error in a fiber optic gyroscope. The polarity of the drive signal to the phase modulator of the gyroscope is switched periodically. The scale factor consequently changes. The phase and amplitude of coherent pickup error generated in the gyroscope circuits do not change during the switching. Therefore, nearly all of the coherent pickup error is subtracted out of the gyroscope signal during the digital signal processing of the signal.

Abstract: A vertical cavity surface emitting laser having a planar structure, having an implantation or diffusion at the top of the mirror closest to the substrate or at the bottom of the mirror farthest from the substrate, to provide current confinement with the gain region, and having an active region and another mirror formed subsequent to the implantation or diffusion. This structure has an implantation or diffusion that does not damage or detrimentally affect the gain region, and does provide dimensions of current confinement that are accurately ascertained. Alternatively, the implantation or diffusion for current confinement may be placed within the top mirror, and several layers above the active region, still with minimal damage to the gain region and having a well-ascertained current confinement dimension.

Abstract: A micromechnical sensor having a polysilicon beam that is an integral part of the diaphragm resulting in a frequency of the beam that is a direct result of the pressure applied to the external surface of the diaphragm. Fabrication of this resonant microbeam sensor has no backside wafer processing, and involves a process and layout independent of wafer thickness for high yield and robustness. Both the diaphragm and resonant beam are formed from polysilicon. The sensor may have more than one resonant beam. The sensor beam or beams may be driven and sensed by electrical or optical mechanisms. For stress isolation, the sensor may be situated on a cantilevered single crystal silicon paddle. The sensor may be recessed on the isolating die for non-interfering interfacing with optical or electrical devices.

Abstract: A switch actuator is provided in which any one of a plurality of rotatable cams is capable of actuating a single switch simultaneously with controlling another mechanism, such as a gas valve that is associated with that particular rotatable cam. When used in conjunction with a kitchen range, each of the rotatable cams controls an associated gas valve which, in turn, controls the flow of natural gas to an associated burner. Each of the rotatable cams is disposed within an associated one of a plurality of openings formed through the thickness of a movable member. The movable member is attached in sliding relation with a stationary member which, in turn, can be attached to a stationary device such as a kitchen range. Each of the openings formed through the thickness of the movable member is provided with an edge that is shaped to perform the function of a cam follower. This cam following edge is disposed in contact with a cam surface attached to the rotatable cam.

Abstract: A device for providing a bias modulation at a proper frequency to the counterpropagating light waves in the sensing coil of an interferometric fiber optic gyroscope. The photodetector detects the light which has exited the sensing loop, and converts it to an electrical signal that is demodulated by two phase sensitive detector. One phase sensitive detector demodulates the signal that is in phase with the bias modulation signal and the other phase sensitive detector demodulates the quadrature signal with respect to the modulation signal, and controls the frequency of the bias phase modulator driver so as to reduce the quadrature to a minimum and to keep the modulator frequency at the proper frequency of the sensing coil. Increased intensity modulation can be attained with a DC voltage applied to an electrode of the modulator to produce the quadrature signal.