Abstract: A pressure sensor includes a pressure sensitive element for sensing a distributed fluid pressure and producing a signal in response. The pressure sensitive element is configured to be mountable on an airfoil or a hydrofoil, for example as a thin film piezoelectric element. The sensor finds applications, for example, in measuring lift or drag on the airfoil or hydrofoil.

Abstract: A patient activity monitoring system that allows caregivers of multiple patients to work more efficiently and with reduced cost, while increasing the quality and level of patient care. The system includes a plurality of remote monitoring subsystems, a plurality of user notification units, and a central monitoring unit with a Graphical User Interface (GUI) communicably coupled between the remote monitoring and user notification units. Each remote monitoring subsystem includes a remote monitoring unit, and a sensor device associated with a respective patient that detects one or more activity and/or physiological parameters of the patient. A simplified user interface including the GUI and the user notification units provides indications of the type and level of assistance required by one or more patients to caregivers at centralized and remote locations.

Abstract: A patient monitoring system includes a replaceable laminar sensor to be placed on a bed, the sensor including distributed force sensing elements providing output signals to processing apparatus including a near-bed processor and a central processor coupled to the near-bed processor by a wireless communication link. The processing apparatus applies spatial weighting to the sensor output signals to derive the force distribution across the sensor, and processes the force distribution over time to generate patient status information such as patient presence, position, agitation, seizure activity, respiration, and security. This information can be displayed at a central monitoring station, provided to a paging system to alert attending medical personnel, and used to update medical databases. The sensor may be manufactured from layers of olefin film and conductive ink to form capacitive sensing elements.

Abstract: A patient monitoring system includes a replaceable laminar sensor to be placed on a bed, the sensor including distributed force sensing elements providing output signals to processing apparatus including a near-bed processor and a central processor coupled to the near-bed processor by a wireless communication link. The processing apparatus applies spatial weighting to the sensor output signals to derive the force distribution across the sensor, and processes the force distribution over time to generate patient status information such as patient presence, position, agitation, seizure activity, respiration, and security. This information can be displayed at a central monitoring station, provided to a paging system to alert attending medical personnel, and used to update medical databases. The sensor may be manufactured from layers of olefin film and conductive ink to form capacitive sensing elements.

Abstract: A gait analysis system includes a shoe insert for use in a shoe worn by a subject while walking as part of a process of collecting gait data. The insert has force-sensing sensors distributed to define a sensing aperture, and each sensor provides an electrical output signal. Processing apparatus is communicatively coupled with the sensors. The processing apparatus calculates a gait line represented by a series of points, wherein each point is calculated as a spatially-weighted average of samples of the sensor output signals over the sensing aperture. The processing apparatus includes a portable telemetry transmitter worn by the subject. The transmitter is connected to the sensors to receive the sensor output signals, and transmits a radio signal carrying the sensor information. A stationary receiver receives the sensor information in a transmission from the transmitter, and provides the sensor information to a personal computer or similar workstation.

Abstract: A sensor system preferably for use in a vehicle airbag deployment system employs spatial shading techniques and centroiding analysis to calculate an equivalent point load in two dimensional space. The location of the equivalent point load, as well as the weight of the passenger as determined from the sensors, are used to construct a set of fuzzy set logic boundaries defining different modes of deploying the airbag. The filmy set logic boundaries may include a full deployment, soft deployment, no deployment and other intermediate deployment zones. In the event of a vehicle airbag incident, the airbag is deployed in accordance with the fuzzy set logic boundary in which the weight and equivalent point load of the vehicle occupant are located.

Abstract: A sensor system preferably for use in a vehicle airbag deployment system employs spatial shading techniques and centroiding analysis to calculate an equivalent point load in two dimensional space. The location of the equivalent point load, as well as the weight of the passenger as determined from the sensors, are used to construct a set of fuzzy set logic boundaries defining different modes of deploying the airbag. The fuzz set logic boundaries may include a full deployment, soft deployment, no deployment and other intermediate deployment zones. In the event of a vehicle airbag incident, the airbag is deployed in accordance with the fuzzy set logic boundary in which the weight and equivalent point load of the vehicle occupant are located.

Abstract: A wideband, derivative-matched, continuous aperture acoustic transducer includes a first sensor area having a predetermined spatial shading and a second sensor area having a spatial shading which is the spatial derivative of the spatial shading of the first area; the first and second spatial shaded areas are superimposed and co-extensive along the sensing axis.

Abstract: A wideband, derivative-matched, continuous aperture acoustic transducer includes a first sensor area having a predetermined spatial shading and a second sensor area having a spatial shading which is the spatial derivative of the spatial shading of the first area; the first and second spatial shaded areas are superimposed and co-extensive along the sensing axis.

Abstract: A mirror and system for wavefront control includes a piezoelectrically active pellicle with a conductive front mirror surface, and an electron gun for depositing charge on the rear surface of the pellicle. The pellicle is formed of facing plies of polyvinylidene fluoride having opposite poling, so that efficient bimorph actuation is achieved while maintaining substantially constant pellicle thickness and stable x-y planar position coordinates. A phase corrector plate provides a fixed flatness correction for irregularities of the mirror surface, and an initial charge distribution is applied to achieve a reference mirror contour. Potentials above and below a front surface reference potential, and different frame rates, are achieved by controlling the electron energy to selectively charge by primary or secondary charging processes. A feedback system may establish the initial reference contour, and thereafter effect real time wavefront adjustment of a beam reflected from the front mirror surface.

Abstract: The present invention is a device for characterizing pressure distributions on a rigid surface with respect to at least one reference (x) axis. The device includes a substrate electrode disposed on the rigid surface for which the pressure distribution is to be characterized. An electrically conductive material may form the substrate electrode, or where the rigid surface itself is electrically conductive, that rigid surface may form the substrate electrode. A piezo film is disposed on and overlying the rigid surface. A sensor electrode is disposed on and overlying at least part of the piezo film. In one form of the invention the sensor electrode of a measurement cell is a composite electrode including at least two electrically isolated portions.

Abstract: A closed loop system sends one portion of a coherent laser beam along a first path and another portion of the beam along a second path which is directed at a mirror formed on piezoelectric membrane. After reflection, both return beams are mixed on a photodetector array and the array output is analyzed to determine the values of a charge distribution on the piezoelectric membrane which will null or maintain constant the phase of the mixed beam.

Abstract: The present invention is a two beam, double pass, phase shifting interferometric system for characterizing the phase profile of a radiation path. In the preferred form of the invention, a monochromatic beam is split into a reference beam and a test path beam. The test path beam is directed toward a fixed reflector which in turn directs that beam to the image sensor with a fixed length in the direction of propagation. The reference beam is directed to a movable reflector which directs that beam also to the image sensor, while introducing phase modulation. The system provides a measure of phase offset introduced into the reference beam at times of minimum or maximum intensity as measured by each photo detector in the image sensor, as the phase modulation of the reference beam is stepped over one complete wavelength.

Abstract: A method and apparatus is disclosed in which a piezoelectric film is used to control or dampen vibrations in a mechanical system. Voltage of proper amplitude and phase is fed across the piezoelectric film to induce strain in the film of appropriate phase, amplitude and frequency to dampen beam vibrations of the mechanical system. The film may be applied directly to the mechanical system or an intermediate viscoelastic layer may be provided. Various control functions are described for determining the correct voltage to be applied to the film.

Abstract: A method and apparatus is disclosed in which a piezoelectric film is used to control or dampen vibrations in a mechanical system. Voltage of proper amplitude and phase is fed across the piezoelectric film to induce strain in the film of appropriate phase, amplitude and frequency to dampen beam vibrations of the mechanical system. The film may be applied directly to the mechanical system or an intermediate viscoelastic layer may be provided. Various control functions are described for determining the correct voltage to be applied to the film.