Abstract: A multi-station RF thermometer and alarm system measures temperatures and/or percent relative humidity at remote locations by RF weather stations, and displays received temperature and/or other weather data telemetry on a multi-station base station that provides out-of-bounds alarm signal indications whenever temperatures are outside of user-selectable minimum and maximum values. Randomized transmission times in one embodiment and two-phase unique transmission schedules in another lessen the possibility of on-going collisions between two or more transmitters contending for the base station at the same time. Redundant data transmission lessens the possibility of environmental noise interference.

Abstract: An active early warning system for storms that uses weather radar data as input to a computer which in turn projects the likely path of a tornado. The computer then accesses a database which contains telephone numbers and the telephone's geographic location. The phone numbers which are in the projected path of the tornado are dialed automatically and the called parties are notified via computer message. This provides individuals who are the most likely potential victims of a tornado with the earliest possible notification. By using geographic data which is related to the telephone number, the computer will not waste any time calling numbers which are not in the path of the tornado. This avoids unnecessarily alarming individuals who are not at risk and ensures that those who are at risk are notified.

Abstract: A visibility sensor system includes a housing having a sensor head opening. A removable sensor head assembly is removably coupled to the housing within the sensor head opening. The sensor head assembly has a sensor enclosure and a connector. An electronics module is coupled to the sensor head through the connector. A rain sensor determines the presence of rain and causes shutters to cover openings in the sensor exclosure. In other embodiments, the sensor enclosure is configured to develop a pressure differential internally to minimize contamination of light source and light detector.

Abstract: An apparatus and a method for operating a rain sensor (10) that outputs a sensor signal (18, 22) as a function of the wetting of a window (11) are proposed, having a controller (16) which as a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10) for regulating the sensor signal (18, 22); for signal evaluation, the sensor signal (18, 22) and in addition the control signal (28) are used for tripping switching events of a device.

Abstract: For transmitting early warning signals of slick road conditions (1, 2, 3, 4), in addition to automatic measuring stations (AMS1-AMS5) that have probes for the weather conditions and the freezing point of liquid present on the road, virtual stations (VS1-VS 11) are created and used for which weather data, freezing point data, and parameters are taken from the automatic measuring stations in order to transmit an early warning of slick conditions for the virtual stations also, by means of an evaluating device (5).

Abstract: A wireless gauge alert system including a near empty sensor, a near full sensor, a transmitter, a receiver, and an alert device used to monitor the fuel level status of a liquid fuel or pressure (vessel) tank having a measuring device with an output member and gauge. Upon detection of a predetermined near empty condition, the transmitter sends an encoded wireless alarm signal to the receiver. The alert device then generates a user notification signal. The receiver and alert device, which preferably comprise an LED, are held in a housing having a plug extending therefrom to mount the housing to an electrical socket in a high traffic area. An alternate alert system includes a receiver unit coupled with a computer that allows either the user or a vendor computer to monitor the status of the sensor and respond accordingly. Another alternate alert system includes multiple zone remote assemblies for installation on separate fuel tanks to be monitored.

Abstract: An apparatus and a method for operating a rain sensor (10) that outputs a sensor signal (18, 22) as a function of the wetting of a window (11) are proposed, having a controller (16) which as a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10) for regulating the sensor signal (18, 22); for signal evaluation, the sensor signal (18, 22) and in addition the control signal (28) are used for tripping switching events of a device.

Abstract: The present invention is a two-part wind advisory system comprising a ground station at an airfield and an airborne unit placed inside an aircraft. The ground station monitors wind conditions (wind speed, wind direction, and wind gust) at the airfield and transmits the wind conditions and an airfield ID to the airborne unit. The airborne unit identifies the airfield by comparing the received airfield ID with airfield IDs stored in a database. The airborne unit also calculates the headwind and crosswind for each runway in both directions at the airfield using the received wind conditions and runway information stored in the database. The airborne unit then determines a recommended runway for takeoff and landing operations of the aircraft based on the runway having the greatest headwind value and displays the airfield ID, wind conditions, and recommended runway to the pilot.

Abstract: A severe weather detection apparatus for detecting severe weather and method of detecting and warning of approaching severe weather conditions is provided. The severe weather detector apparatus includes a barometric pressure sensor and computerized means for calculating the rate of change in the barometric pressure. By monitoring and deriving a value representative of the rate of change in the barometric pressure over time, a threshold is established and compared to the current rate of change in the barometric pressure. The derived rate of change is compared to a value stored in the device which reflects approaching severe weather conditions. Rates of change which may indicate the approach of severe weather activate a voice-enunciated alarm that announces the potentially dangerous barometric activity. The severe weather detection apparatus is portable and suitable for battery power and installation in the same manner as a home smoke alarm or carbon monoxide detector.

Abstract: ThunderCall is a computer based system for delivering NWS(National Weather Service) severe weather warnings as a message (personalized information, if desired) via an automated dialing system to live persons and to automated recorders comprising the steps of: forming a database of names with their respective geographic locations; capturing a NWS Bulletin reciting the location of a severe storm; validating a relevant Bulletin into a Valid Bulletin by determining from the storm's location that it represents an imminent severe storm danger to at least one person of said database (capable of 10,000,000 or more persons) recording, if desired, an individual personal urgent warning to the name of the intended recipient of the Valid Bulletin; combining, if desired, said personal warning with a generic severe storm warning for said recipient; and, sending said Valid Bulletin with said combined warnings to said person whereby he is alerted within seconds of the release time of said National Weather Service bulletin to

Abstract: A multi-station RF thermometer and alarm system measures temperatures and/or percent relative humidity at remote locations by RF weather stations, and displays received temperature and/or other weather data telemetry on a multi-station base station that provides out-of-bounds alarm signal indications whenever temperatures are outside of user-selectable minimum and maximum values. Randomized transmission times in one embodiment and two-phase unique transmission schedules in another lessen the possibility of on-going collisions between two or more transmitters contending for the base station at the same time. Redundant data transmission lessens the possibility of environmental noise interference.

Abstract: A pager receiver based system provides a method and an apparatus for receiving and detecting a tornado alert or other severe weather alert from the National Weather Service, determining the region or grid block to which the alert applies, and broadcasting an alert signal to a plurality of pager receivers, all programmed with the same sub-address, within that region or grid block.

Abstract: A device and method are provided for warning of the approach of severe weather in a geographical area. The device includes a receiver for receiving a broadcast signal having a first component corresponding to one of a plurality of geographical areas and the second component corresponding to one of a plurality of types of severe weather. Selection devices are provided for allowing the user to select the geographical area and the type of weather for which the warning device monitors. A warning signal is provided to the user if the geographical area of the broadcast signal is the selected geographical area and if the type of severe weather approaching is of a type of weather for which the warning device is monitoring.

Abstract: A novel earthquake sensing device is disclosed. The earthquake sensing device comprises a vertical vibrating wave sensing module, a horizontal wave sensing module and a determination module to determine the existence of an earthquake, based on, in combination, the vertical waves and the horizontal waves of an earthquake. In determining the existence of an earthquake, both the vertical waves and the horizontal waves of the earthquake are taken for consideration. Errors in the determination of earthquakes may thus be avoided.

Abstract: A new and useful apparatus for automatically correcting for the actual altitude of an aircraft, under non-ISA temperature conditions is provided. An apparatus according to the present invention can be particularly useful in automatically providing altitude correction output to a navigation and control system for an aircraft at selected points along an aircraft flight path where terrain clearance under non-ISA temperature conditions is an important operational parameter.

Abstract: A pager receiver based system provides a method and an apparatus for receiving and detecting a tornado alert from the National Weather Service, determining the region to which the alert applies, and broadcasting an alert signal to a plurality of pager receivers, all programmed with the same pager number, within that region.

Abstract: To differentiate between lightning strikes and tornado generated electromagnetic signals, a tornado detection system and method is made up of RF receiving circuits which receive signals at two frequencies, while implementing a time variable automated calibration and the use of special algorithms, to reliably detect tornado events and to signal an alarm. A network of such systems can be implemented, using a plurality of antennas which are capable of discerning a directional vector, and integrating the directional information from multiple units by effecting a triangulation calculation in a server terminal to determining a position and path of an approaching tornado.

Abstract: An apparent temperature monitor and/or alarm comprises separate sensors that monitor at least ambient temperature and humidity of a location in which an occupant resides. It has been noted that certain elderly and/or poor residents of urban areas may be unable to self-monitor their environmental and health situation, and that use of an apparent temperature monitor/alarm may assist in preventing mortality of elderly occupants or those who are unable to fend for themselves. A system for monitoring a large number of remote locations may also be established and appropriate health or safety personnel may be directed from a central monitoring location to investigate specific occupants or remote locations indicative of unhealthy environmental conditions.

Abstract: A weather alert system to warn a user when an emergency signal has been broadcast and to simultaneously activate a television or other visual information source and to select a predetermined informational channel. The weather alert system includes a signal detector for detecting a broadcast alarm signal and for generating an activation signal upon detection of the alarm signal. A remote controller is operatively connected to the signal detector for producing a remote control signal in response to said activation signal. The remote control signal is utilized to trigger the activation of a visual information source such as a television or a computer to provide visual information relating to the hazardous condition.

Abstract: A weather warning apparatus and associated method notifies a user when weather alerts are issued according to geographical areas of interest and weather notification parameters that are set by the user. The weather warning apparatus includes a communication link for receiving transmitted alerts, such as weather warnings, watches and statements, civil emergencies, and the like. The weather warning apparatus also includes a user interface for selecting geographic areas of interest and weather notification parameters, such as weather events that may be of interest to a user at a desired time of day or time interval. The user's selection of geographic area and weather notification parameters allows the weather warning apparatus to filter out unwanted weather alerts that are outside of the desired geographic area, type of weather event notification, time or time interval.

Abstract: A severe storm warning system includes an atmospheric pressure sensor utilizing an air-filled chamber with a first pressure sensor mounted between the interior of the chamber and the atmosphere and being located within the chamber interior and a second pressure sensor mounted between the interior of the chamber and the atmosphere and being located outside the chamber. Both sensors are formed of multiple-plate, floating plate capacitors which are movable in response to pressure changes. Electronic circuitry periodically determines what pressure changes have occurred and compares the changes to the changes associated with a predetermined signature of the type of severe storm being determined. Indicators including alarms are provided if a known sequence of pressure changes is detected.

Abstract: A crop frost prediction system (20) is provided. The system (20) exposes a thermally radiant surface (22) to atmosphere (26) and senses the temperature of the thermally radiant surface (22). The sensed temperation, alone or in combination with other variables, is used by a processor (38) to calculate whether frost is likely to occur. The system (20) capitalizes on the understanding of the inventor that the thermally radiant surface (22) will dissipate heat (24), and thus have a lower temperature than the ambient air, under conditions of low humidity and clear night sky.

Abstract: A meteorological information system useable by aircraft pilots and others. A receiver-calculator unit receives raw meteorological data and site-specific physical data from a ground-based weather station having a signal transmitter for broadcasting signals conveying data about weather conditions at the station. The transmitted raw data signals are received by the receiver-calculator unit in the aircraft. The receiver-calculator unit may feature an input with which the operator inputs information about the physical character, such as the heading, of the runway of interest. The receiver-calculator unit processes both received raw weather data and received site-specific physical data, and/or operator-input data, to derive additional meteorological information. The raw and derived weather conditions information is displayed by the unit to be available to the aircraft pilot during landing or take-off maneuvers.

Abstract: A method and system for sensing surface contamination on an aircraft having a control surface. A control element including the control surface is connected to the aircraft by a hinge. The method and system sense a control surface hinge moment about a line on the hinge of the aircraft. A control surface steady hinge moment coefficient is calculated from control surface hinge moment data representing the hinge moment over a period of time. An unsteady hinge moment is calculated which is dependent on the control surface steady hinge moment coefficient. By using a value which is relatively constant during uncontaminated surface conditions, this value can be compared against calculated values to check for variations. If the calculated unsteady value varies from the known uncontaminated values, a warning may be given, alerting an operator of unsafe conditions. This warning is given before a critical value is reached, allowing the operator a period of time to react to the warning.

Abstract: An improved safety related compact hand-portable apparatus for home or office use, EQ-Alert.TM. is ceiling or shelf mountable, activating upon sensing a minimum-threshold earthquake preferably of about 3.25/Rictor-scale intensity, instantly emitting a series of approximate 110-decibel level siren-alarms; preferably along with activation of a safety-lamp to illuminate an immediate floor-area in event of community power-outage. A preferably dry-cell powered dc/electronic IC-chip timer-circuit, limits duration of the audible-alarm, triggered by sufficient movement of an internal omni-directional mercury n.o./jiggle-switch. Upon completion of the timed audible-alarm and optional voice-chip announcement, the timer-circuit sequences a conventional integral superheterodyne-AM/radio user has preset to a local Conelrad/news-station, for ongoing notification of any earthquake rescue procedures.

Abstract: A subscriber (125) to a radio communication system (110) is automatically notified of an event affecting or potential affecting a particular geographical locality. The radio communication system obtains such event and locality information (310, 320), and uses the locality information to transmit the event information to subscribers of that system potentially affected by the event. In one embodiment, the system automatically uses only transmitters that service at least a portion of the affected locality to transmit the event information (330, 340). In another embodiment, the system automatically transmits event information selectively to those subscribers having a location designation corresponding to the particular locality (410, 420).

Abstract: A roof moisture detection assembly includes an imaging system for obtaining thermal and visible images of a roof surface, an imaging system support ructure for mounting the imaging system in a position elevated relative to the roof surface, a reference target mounted on the roof surface, and an image-processing system adapted to compare current thermal and visible images of the roof surface with previous thermal and visible images of the roof surface and detect shapes and areas of anomalous features, and to compare the current thermal and visible images with each other and detect shapes and areas of anomalous features.

Abstract: A tornado detector comprising a sensor (30) for sensing the presence of sound having a frequency of about one hertz and for providing a sound sense signal in response thereto, a filter (50) to attenuate said sound sense signal wave components having frequencies greater than those which correspond to sound having a frequency of about one hertz, and an alarm (101) for generating an alarm signal in response to said filtered sound sense signal.

Abstract: A device for triggering a control and/or warning process in a motor vehicle has sensors for determining the existing value of the crosswind actually acting on the vehicle. A crosswind warning device for motor vehicles which permits of a reliable warning for the driver even under varying conditions of the wind, has a first device for the determination and evaluation of the limiting value of crosswind in the motor vehicle for determining a crosswind speed limiting value which is dependent on the actual travel conditions of the vehicle. The values detected by a second device for the determination of the existing crosswind value are fed to the first device and compared with the detected crosswind speed limiting values. A driver-information device is actuated as a function of the comparison.

Abstract: The intelligent alarm system of the present invention provides a reliable, low cost system for alerting a user to the presence of snow outside of a building. The system includes a sensor and an intelligent alarm clock for use inside a building or dwelling. The system can be set by a user to signal an alarm a programmable amount of time earlier or later than the user's normal waking time if an accumulation of snow is detected. The system is capable of processing preprogrammed data, user entered data and data accumulated from the sensor to determine whether a true snow condition exists and to generate an appropriate alarm signal.

Abstract: A multi-station RF thermometer and alarm system measures temperatures at remote locations by RF thermometers, and displays received temperature telemetry on a multi-station base station that provides out-of-bounds alarm signal indications whenever temperatures are outside of user-selectable minimum and maximum values. Randomized transmission times lessen the possibility of on-going collisions between two or more transmitters contending for the base station at the same time. Redundant data transmission lessens the possibility of environmental noise interference. The redundant data transmitted at random times includes a unique channel ID code, house-keeping data, the current temperature and/or time-to-next-transmission data. The temperature sensing transmitters operate at a low duty cycle with low peak current consumption resulting in long battery life. The multi-station base station may be AC- or battery-powered.

Abstract: The indicator light is constituted by a panel supporting juxtaposed and alternating neon tubes of blue, yellow, green and red color, these colors being assigned to the cardinal points north, east, south and west respectively. These tubes have voltage applied by means of a selector controlled by a weather vane, activating permanently the neon tubes of the color corresponding to the position of the weather vane. A series of colored lamps, displaying the Beaufort scale, indicates the wind velocity by means of a selector controlled by the anemometer. Colored light sources indicate the air pollution level.

Abstract: A tornado alarm that monitors humidity, static charge in the air and the barometric pressure. Nothing happens until the level of static electricity increases to a set amount over a stored base level and the humidity reaches 100 percent. At this point the first stage alarm is activated. The device sends out an initial blast followed by a report every 60 seconds during this mode of operation. At this point, the user is awakened by the alert. The user then can turn on news reports to verify danger. Once awake, if danger exists, the user can prepare for a tornado and be ready. When the barometric pressure reaches 28 millibars, the third condition is reached. Under most circumstances, a tornado is then immanent. This sets the device into the second stage alert mode. In this mode, a continuous alarm sounds.

Abstract: Local telephone exchanges in a threatened geographical area connect to their subscribers and transmit a recorded warning message. This is done in response to transmission of threat data communicated from one of several remote computer terminals to a central computer. The central computer has a data storage device upon which is stored a local exchange database and preferably recorded warning messages. Upon receipt of the threat data from the remote computer terminal, the central computer is connected in communication with the local exchanges in the threatened geographical area and instructs the local exchanges to connect to its subscribers and provides instructions or a warning message to be played to the subscribers who go off-hook.

Abstract: A visibility sensor system includes a housing having a sensor head opening. A removable sensor head assembly is removably coupled to the housing within the sensor head opening. The sensor head assembly has a sensor enclosure and a connector. An electronics module is coupled to the sensor head through the connector.

Abstract: Apparatus and methodology for detection of lightning. The invention includes an antenna and amplifier for receiving the electrostatic and/or electromagnetic discharges of lightning and electrical noise and outputs an analog electrical signal representative of the discharge. The analog signal is applied to a threshold detection circuitry whose output is activated when the input signal rises above a predetermined level. The output of the threshold circuitry is a series of pulses of varying length. A computer or other programmable device is connected to the output of the threshold circuitry and opens an event window when the first pulse is received and determines the number of pulses received and the total duration of the pulses during the event window. The number and total duration of the pulses is compared to stored pulse signatures of lightning discharges and man made electrical noise.

Abstract: A self-locating remote monitoring system (750) includes a supervising base station (754) and one or more remote monitoring units (752). A remote unit (752) includes a navigational receiver (756) operating with an existing navigational system for providing a remote unit location (759) and includes a transmitter (758) for communicating the location (759) to the base station (754) for display (772). The remote unit (752) includes one or more physiological/environmental sensors (760) for monitoring at the remote location. In a specific embodiment a change in sensor status (761) results in the status and the location being transmitted to the base station (754). The base station (754) includes alarms (776) and displays (772) responsive to the change in status. One embodiment defines a man-over-board system (300) which combines water immersion (308) and distance (334) from the base station (318) to trigger an alarm (332) and begin location tracking (324).

Abstract: A severe weather warning system is provided including an indicator mechanism adapted for providing an indication of a weather disturbance upon the receipt thereof. A modem has an outlet port connected to a conventional phone and an inlet port connected to a telecommunication network. During use, the modem has a first mode of operation for allowing the transfer of audio signals between the inlet port and the outlet port and a second mode of operation for when a weather disturbance is detected. Next provided is control circuitry adapted for transmitting to the indicator means the indication of a weather disturbance.

Abstract: The present invention is an earthquake detector and alarm system designed to detect even very low seismic vibration activity and warn the user. The present invention's detector sensor is selective to certain frequencies that are most probable in seismic activity and resistant to frequencies not typical in seismic activity, thus providing a high level of seismic activity detection and a low level of false triggers from non-seismic sources. It's purpose is to notify dwelling occupants that an earthquake is underway thus removing doubt that emergency action should be immediately taken. The clear, unmistakable warning provided by the present invention is valuable for sleeping occupants who might otherwise sleep through the initial activity in a seismic event, loosing valuable time to take emergency actions.

Abstract: This invention relates to an electrostatic field measuring device which incorporates the phenomena of floating electrodes. The invention has no moving parts and is based on the use of the discharge frequency of floating electrodes as a measure of electric field intensity.

Abstract: A device for transmitting sensor signals in a bicycle includes a sensor for sensing an operational condition of a bicycle component and for outputting a sensor signal having a selected type. A digital transmission circuit operationally associated with the sensor outputs a digital message in response to the sensor signal. The digital message includes 1) a digital sensor value comprising a series of bits representing a value of the sensor signal; and 2) a digital identification value for indicating the selected type of the sensor signal. Such a message allows a sensor having any physical design to be connected to the computer.

Abstract: A data acquisition apparatus that includes a recorder device of an event's ime and date signified by the opening of an external trigger switching circuit in combination with a complimentary interrogator device for collecting data from the recorder device. The recorder device's components comprise a battery powered source with a power regulator, a processor, a dip-switch identifier, a programmable read only memory, a clock/ calender with random access memory, a timing/control subcircuit interface that connects to the external trigger switching circuit(s) and an output interface port for data transmissions with the interrogator device. The recorder's timing/control subcircuit interface extends battery life by sensing and transmitting electrical pulses through each external trigger switching circuit. The interrogator device is portable and has multiple functional capabilities.

Abstract: A device for signaling a predetermined soil moisture condition includes a switching tensiometer that closes a switch when the root water tension reaches a predetermined level; a power source connected to the switching tensiometer; and a signal connected to the switching tensiometer so that when the switching tensiometer closes the switch, power source is connected to the signal operate the signal to indicate that the predetermined soil moisture condition has been reached. The signal preferably includes a spring-loaded flag that operates between a retracted position and an extended signal position; a latch for releasably securing the flag in its retracted position, and an electrically operated release that releases the latch to allow the flag to operate to its extended signal position.

Abstract: In a rain sensor, a sensor field is arranged between two windshield wiper blades which lie one above the other on a windshield. The sensor field is thus located outside of the field of view of the driver and is wiped by the lower windshield wiper blade. The sensor field is connected to an evaluation circuit arranged on a wiper motor by connecting lines which pass around the lower wiper blade.

Abstract: A roof moisture sensing system includes (1) a radio frequency pulse transter, (2) a moisture sensor disposed on a roof, and (3) a radio receiver adapted to monitor resonance of the moisture sensor activated by a pulse transmitted by the pulse transmitter. The receiver is adapted to analyze the resonance of the sensor to determine the presence of moisture in the sensor. The transmitter and the receiver can be remote from the sensor and the roof.

Abstract: A tornado warning system having means for monitoring seismic waves of a predetermined frequency range including long-period seismic waves and short-period seismic waves. The seismic waves are associated with and produced in the ground as a result of an approaching tornado. The warning system comprises means for detecting the seismic waves including the long-period seismic waves and the short-period seismic waves and for providing an electrical output indicative thereof. Circuit means are provided for processing the electrical output to provide an output signal indicative of the long-period seismic waves and the short-period seismic waves. Alarm means are provided for receiving the output signal from the circuit means to generate an alarm to warn of the presence of a tornado.

Abstract: The present invention provides a weather forecast apparatus and a method for the same, to systematically classify a measured radar image based on results of pattern classification of past radar images so as to use the classified radar image. In the present invention, rapid forecasting is possible by making the FNN model previously learn based on data of each class (and indexes for forecast times) obtained by classification of past weather data for every resembling pattern. In addition, a calculation procedure for improving the classifying ability of patterns can be established by varying the procedure for calculating feature quantities with regard to the radar image by using the learning of the TNN model. Furthermore, systematic classification of a pre-learned image can be realized by performing self organization with regard to compound feature quantities extracted from a radar image in the PNN model, a typical example of which is a competitive learning model.

Abstract: Systems and methods for traffic control use scanning transmissometers to determine visibility along an extended stretch of roadway. When areas of decreased visibility are detected, such as dense localized pockets of fog, appropriate warning information is provided to drivers over warning devices positioned along the roadway. Information from the transmissometers is used to develop a speed profile, that is an indication of safe speed as a function of position along the roadway. Traffic sensors detect variations in behavior from that specified by the warning devices, such as a very slow vehicle, and modifies the warning information according. A computer readable medium contains a computer program for implementing the systems and methods.

Abstract: An infrasonic frequency resonant circuit and method for use thereof. An electric power distribution system is employed both as antenna for ISF signals and as a source of inductive reactance for a resonant circuit tuned to a band within the ISF spectrum. A capacitor is placed from the neutral conductor to the ground conductor at an ac power outlet in a structure to form a resonant circuit ordinarily tuned to a band within the ISF spectrum. An ISF spectrum analyzer is connected to the neutral and ground terminals of the resonant circuit to visualize ISF electromagnetic signals induced on the electric power distribution system in both the frequency domain and the time domain and so as to be more readily evaluated.

Abstract: A switch including a mass suspended above a base by a flat horizontal spring has electric contacts that close in response to the initial shocks of major earthquakes and activates safety devices before the onset of destructive ground motions. The vertical unidirectional seismic switch can be manufactured by micromechanical photolithography and is integrated with electromechanical safety devices to latch cabinets closed, secure movable objects, shut off gas, water, and electric utilities, activate alarms, early warning networks, and related automated response systems. The device is fully self contained, consumes no power until activated, is inexpensive to produce, and impervious to nonearthquake noise in that it is designed to respond specifically to the vertical acceleration and displacement characteristic of the initial shock waves of a major earthquake.