Abstract: An adapter for wireless data transmission, in particular according to the “Bluetooth Low Energy” standard, is proposed. The adapter has a cylindrical housing whose radius is at least twice its height. The adapter includes a wireless transceiver and a processor arranged in the cylindrical housing and connected to the wireless transceiver, and a data interface connected to the processor. The processor is arranged to drive the transceiver and the data interface and can therewith transmit data wirelessly. Because the adapter for wireless data transmission has a flat design, it can be retrofitted in valve positioners. This makes it possible to retrofit commonly used valve positioners that until now do not have an option for wireless transmission of their status data with this adapter. As a result, these commonly used valve positioners also achieve the capability of wireless transmission of their status data.

Abstract: An emergency preparedness alert notification system includes a central siren control system (CSCS) (102) remotely located from a multiplicity of rotating siren systems (104, 106, 108) distributed over diverse wide geographic regions, and which can be automatically tested by the CSCS. The testing method can be automatically repeated to accurately and timely capture test result data, and alarm conditions, from each of the multiplicity of remotely located at least one rotating siren system. Individual components of each rotating siren system are diagnosed and the test results, including any alarm conditions, can be automatically reported via wirelessly transmitted messages 702 to the CSCS. Technical and repair personnel can be dispatched to a particular siren site based on the automatic testing results reported at the CSCS. The retrofittable system can predict a future occurrence of a failure of a particular component of a rotating siren system.

Abstract: A powered room air purifier with a visual indicator of air quality, the visual indicator including: a reflector that defines a forwardly-open-ended reflecting cavity and that includes at least one through-opening in a floor or ceiling of the reflector; at least one diffuser layer that covers the forward opening of the forward-open-ended reflecting cavity; and, at least one LED light source that is positioned within the at least one through-opening, the LED light source and the reflector being configured so that the LED light source is shielded from line-of-sight view along a forward-rearward axis of the powered room air purifier.

Abstract: A rotational angle sensor device and a corresponding method are provided. Two signals which have a phase offset with respect to one another are generated based on a modulated magnetic field using a sensor arrangement. Three signals which have a phase offset with respect to one another are generated from the signals.

Abstract: An aspect of the disclosure provides a rotation angle detecting device capable of detecting a rotation angle of a rotation body rotatable about a central axis. The rotation angle detecting device includes: a sensor magnet, having multiple magnetic poles provided side-by side in a circumferential direction about the central axis and installed to the rotation body; a magnetic sensor, overlapped with the sensor magnet when viewed in a predetermined first direction and capable of detecting a magnetic field of the sensor magnet; and a pair of magnetic parts, provided to sandwich the magnetic sensor in a second direction intersecting the first direction.

Abstract: Technologies and techniques for operating a backup assistance system for a vehicle, wherein the backup assistance system enables travel in reverse along a previously travelled trajectory, wherein a maximum distance for the reverse travel along the previously travelled trajectory is determined and output using a control unit on the basis of an expected error for the reverse travel along the previously travelled trajectory, in which the expected error exceeds a predefined error threshold value.

Abstract: A magnetic detection device that comprises an amplification circuit amplifying a detection signal from a magnetic sensor that is positioned, for example, in a location where an alternating current magnetic field enters as noise, and detects an alternating current magnetic field targeted for monitoring, said magnetic detection device further comprising: timer circuits that are activated in response to a change in the output of the amplification circuit, and if these clock a prescribed time, the outputs thereof change; a logic circuit that treats the outputs of the timer circuits as inputs; and an oscillation circuit for generating an operation clock signal for the timer circuits. The timer circuits are structured such that if the output of the amplification circuit changes to a different direction before the clocking of the prescribed time is complete, the timer circuits are reset.

Abstract: A medication delivery device with a sensing system to determine at least one of a dose set and a dose delivery. The sensing system is operable to detect relative rotational positions of first and second members of the device which are indicative of at least one of an amount of a dose set and an amount of a dose delivered by operation of the device, and generate outputs correlated to such relative rotational positions. The system includes a wiper coupled to the first member, and a sensing band coupled to the second member for physically contacting the wiper as the second member rotates relative to the first member. A controller electrically communicates with the sensing system to determine, based on the generated outputs of the sensing system, at least one of the amount of the dose set and the amount of the dose delivered by operation of the device.

Abstract: A displacement detection unit includes a magnet and a magnetic detector. The magnet includes a first magnetic-pole region polarized into a south pole and a second magnetic-pole region polarized into a north pole, and generates a magnetic field around the magnet. The magnetic detector is movable relative to the magnet in a first direction, and detects a change in the magnetic field and thereby detects a displacement of the magnet in the first direction. The magnet includes a transition section in which a ratio of a magnetic volume of the second magnetic-pole region in a second direction to a magnetic volume of the first magnetic-pole region in the second direction gradually varies in the first direction. The second direction is orthogonal to the first direction.

Abstract: The present disclosure relates to an apparatus for correcting an offset of a resolver of an environment-friendly vehicle. The apparatus includes a resolver offset correcting error determining unit configured to determine whether a resolver offset correction error occurs, by determining whether an engine clutch is released and a torque command of a motor. The apparatus further includes a motor speed change value calculating unit configured to calculate a change value of a speed of the motor when it is determined that the resolver offset correction error occurs and a controller configured to extract a resolver offset change value by using a resolve offset change value table for the change value of the speed of the motor.

Abstract: Aspects of the disclosure provide a radio transmitting device that includes a memory, a controller and a wireless communication processing circuit. The memory is configured to store correction data for correcting an azimuth angle detected by a device in a surrounding range around a location where the radio transmitting device is installed. The controller is configured to read the correction data from the memory. The wireless communication processing circuit is configured to transmit a radio signal to carry the correction data to assist the device in the surrounding range to correct the azimuth angle.

Abstract: A multiturn pulley liquid level sensor device for measuring a liquid level in a well and in a container, comprising a mechanical float which is fastened to a fastening rope and which can slide up and down. The fastening rope is installed on one or more pulleys, and as the float moves up and down, the pulley rotates back and forth. One pulley is mechanically coupled to one digital absolute magnetic rotation encoder device, and the encoder device is used for monitoring the total rotation angle of the pulley in real time. By way of using an algorithm, the total rotation angle of the pulley is converted into a distance from the bottom to calculate the height of a liquid level. A multiwheel encoder has two reading types, i.e., one is an electrical signal reading type, and the other is an optical signal reading type. The electronic output of said encoder may be used as input to an industrial control system, or be sent via communications link to a remote or the internet.

Abstract: An indicating circuit for indicating the rotation speed of a fan includes a rotation speed indicating module connected to the fan and receiving rotation speed signals from the fan. The indicating circuit includes a switch and a light emitting element. If the received signal is a high level signal, the switch is turned on, and the light emitting element emits light. If the reeived signal is a low level signal, the switch is turned off, and the light emitting element does not emit light.

Abstract: A gesture-based user interface comprises a wearable portable device storing a gesture profile for each of a plurality of different applications on the wearable portable device to define different gestures for the different applications, wherein each of the gesture profiles includes at least one gesture and a predetermined function associated with the at least one gesture; and a profile web service, wherein the portable device is in communication with the profile web service and is configured to download from the profile web service to the wearable portable device a customizable gesture profile for a particular one of the applications, wherein the customized gesture profile modifies at least one of the different gestures, the customized gesture profile comprising personal preferences of the user regarding the modified gesture, including physical attributes of the user.

Abstract: In the normal rotation direction, a change in the main sensing signal caused by a front edge is defined as a signal change caused by an effective edge, and a change in the main sensing signal caused by a back edge is defined as a signal change caused by an ineffective edge. In the reverse direction, a change in the main sensing signal caused by the back edge is defined as a signal change caused by an effective edge, and a change caused by a front edge is defined as a signal change caused by an ineffective edge. Regardless of the rotation direction, a detection signal generating circuit generates a detection signal including falling-edge changes and rising edge changes caused by the effective edge and ineffective edge respectively. When the direction is changed, the signal change on the detection signal is prohibited. As a result, gear tooth detection discrepancies are prevented.

Abstract: A method and arrangement for detecting rotational movement. The method comprises the steps of arranging a sensor at the end of a rotation axle of a rotating object and at a distance from the rotation axle, arranging a detector external to the end of the rotation axle of the rotating object in such a manner that the distance between the sensor and detector changes as the object turns around its rotation axle, transmitting an poll to from the detector to the sensor, receiving the poll at the sensor, and in response to receiving the poll, transmitting a reply from the sensor to the detector, determining the power used in signaling, and detecting rotational movement on the basis of the change in signaling power.

Abstract: Electrical connection system between a wheel and a bearing-hub assembly, the wheel being mounted on an outer flange of the bearing-hub assembly, and the bearing-hub assembly comprising a rotationally fixed outer ring attached to the vehicle's suspension and an inner ring provided with a centering collar, an open frontal cavity defined in the said centering collar and an axial cavity opening into the said cavity; the connection system having a first connection cable attached to the inner ring and extending inside the axial cavity and the frontal cavity, a second connection cable integrated with the wheel, and a connection element associated with the said centering collar to provide electrical contact that can be selectively disconnected between the first cable and the second cable.

Abstract: The invention relates to a system for detecting the rotational motion of a shaft in a machine housing, comprising a measuring transmitter, which is connected to the shaft, at least one measuring sensor, which is provided on the machine housing, and a measuring transducer connected to a measuring sensor. The invention is characterized in that the measuring sensor(s) (8 and 15 to 20) is/are supplied with current by a separate energy accumulator (11).

Abstract: A resolver signal processing device includes a control portion, a resolver, and an input/output portion. The control portion includes a memory for storing sine wave data for two cycles, and a DMA controller for transmitting to the resolver the excitation signal including a sine wave. A calculation portion provided in the control portion commands, in initial setting, DMA transfer of the sine wave data for one cycle from a reference phase as the excitation signal, and commands, in detecting the rotational angle, DMA transfer of the sine wave data for one cycle from a modified phase as the excitation signal. The modified phase is determined, in the initial setting, based on the phase difference between the excitation signal and a sine wave output signal or a cosine wave output signal, and the rotational angle of the resolver.

Abstract: A rotation state detecting device capable of detecting the direction of rotation of a rotating body includes first and second bridge circuits made up of magneto-resistance effect elements, a first comparator for detecting the increasing/decreasing direction of the center point voltage of the first bridge circuit, a second comparator for detecting the increasing/decreasing direction of the center point voltage of the second bridge circuit, a third comparator for detecting the difference between the center point voltage of the first bridge circuit and the center point voltage of the second bridge circuit, and logic value information deriving means for outputting “1” when the logic values of the outputs of the first comparator and the second comparator are both “1”, outputting “0” when they are both “0”, and continuing to output the previous value at other times, the direction of rotation of the rotating body being determined on the basis of a combination of the outputs of the first, second and third comparators

Abstract: System and method for monitoring a working status of a swimming pool cover assembly. The system comprises a pool cover assembly operably connected to an alarm apparatus; both may be operably connected to a plurality of sensors capable of detecting a working status of the pool cover assembly and sending a signal to the alarm apparatus. The alarm apparatus continually produces at least one humanly perceptible indication corresponding to a working status of the pool cover assembly. The alarm apparatus includes at least one alarm-producing device, such as an audio or visual device, or combination of the two, a receiver operably connected to the plurality of sensors for receiving the signals, a processor operably coupled with the receiver for processing and recognizing the received signals, and software operably coupled with the processor enabling the alarm-producing device to produce the humanly perceptible indication corresponding to the recognized signal.

Abstract: An automated transmission system includes a transmission brake which is used to apply a braking torque to the transmission, while the engine torque is negative and a transmission clutch is disengaged to effect a gear downshift, in order to avoid acceleration of the vehicle when the clutch is released and abrupt deceleration of the vehicle upon completion of the gear downshift.

Abstract: A gyroscope (10) for determining rate of rotation includes a giant magnetoresistor (GMR) (14) attached to a mass (12) oscillating along a first axis. When the gyroscope (10) is rotated, the mass (12) also oscillates along a second axis perpendicular to the first axis. A magnetic element (16), which includes of a strip of magnetic bits (18), is disposed along the first axis, the second axis, or both. The magnetic bits (18) supply discrete magnetic fields. The GMR (14) changes in electrical resistance when exposed to these magnetic fields. A voltage sensor (20) and processor (34) are then utilized to calculate the rate of rotation.

Abstract: The invention relates to a method for monitoring the area of technical rolling bodies, especially their supports, wherein the forces exerted in that area are detected with sensors in order to generate electrical energy and to detect changes in the state of the area. At least one of the sensors (2, 3, 4) arranged in the area of the technical rolling bodies is actively impinged upon with electrical energy and introduces impulses that can be evaluated in the support (1) of the sensor (2, 3, 4) working as actuator. Thus, impulses that can be evaluated can be detected at any given time by the sensors (2, 3, 4) in the area (1) of the technical rolling bodies during monitoring with an electrical evaluation unit.

Abstract: A tire air pressure detection device includes an ideal driving status calculating portion (3e) and a rotational status value compensating portion (3f). The ideal driving status calculating portion calculates an ideal status value (?id) corresponding to a slip value under an ideal driving status without tire slippage. The rational status value compensating portion calculates and ideal rotational status value under the ideal driving status without tire slip based on the regression line calculated by a regression line calculating portion (3d) and the ideal slip status value calculated by the ideal driving status calculating portion.

Abstract: A control apparatus controls a drive of a motor having a movable part via an electric power converter. The control apparatus includes a detecting device for detecting a position of the movable part of the motor; a locking device for locking the movable part of the motor; and a storage device for storing an initial position at which the movable part of the motor is locked for the first time. It is determined that the movable part is locked at an abnormal position when a deviation between the position detected by the detecting device where the movable part of the motor is locked and the initial position stored in the storage means is larger than a predetermined reference distance.

Abstract: A tire air pressure detection device of the present invention includes a warning anticipation timing calculating portion for anticipating a warning timing at which tire air pressure decrease detecting portion will detect the tire air pressure decrease based on rotational status value compensated for by a rotational status value compensating portion. A tire air pressure decrease detecting portion detects a decrease in tire air pressure when a clocked determination time reaches the warning anticipation timing anticipated by the warning anticipation timing calculating portion.

Abstract: Provided is rotational-state-of-wheel detecting apparatus that can avoid output of an incorrect rotational direction during a halt of a wheel. In ECU 10, a signal input section 10a accurately detects wheel speeds and rotational directions of respective wheels 12, 14, 16, 18, and, based on the results, respective computers 10b, 10c, 10d execute ABS control, TC control, and VSC control. On this occasion, switching of the rotational direction is restricted with a computation result of wheel speed of zero, and it is thus feasible to prevent occurrence of a malfunction or state hunting being repetitive switching of signs, due to an external magnetic field during halts of the wheels 12, 14, 16, 18. This further optimizes the state control of a vehicle.

Abstract: A sensor (36) for monitoring rotation of an object (16) about an axis (20) comprises a switch member (40) that is urged into a neutral position and is movable relative to the object (16). A direction of movement of the switch member (40) relative to the object (16) is indicative of a direction of rotation of the object (16). Inertia of the switch member (40) during initial rotation of the object (16) results in relative movement of the switch member (4) away from the neutral position. Centrifugal force during object (16) rotation further enhances the relative movement of the switch member (40). The sensor (36) also comprises a device (56) for monitoring a direction of movement of the switch member (40) and for providing a signal indicative thereof.

Abstract: The invention comprises a micromechanical shock sensor that is formed on the surface of a micro-substrate. A moveable proof mass is formed on the surface with at least one spring connected to the proof mass and the surface. The spring allows the proof mass to move a predetermined distance. Latching means are formed on the surface the predetermined distance from the proof mass. When the sensor is subjected to a sufficient shock, the proof mass moves and contacts the latching means. An indicator means is provided to allow this contact to be readily known by the user.

Abstract: A forklift has a driving wheel capable of being steered by 360°, a steering angle detecting section for detecting a steering angle of the driving wheel, a rotary direction detecting section for detecting a rotary direction of the driving wheel, a running direction judging section for judging a running direction of the forklift based on the steering angle of the driving wheel and the rotary direction of the driving wheel. The forklift further includes a display, advancing chime and reversing buzzer for informing of the result of judgment obtained by the running direction judging section.

Abstract: A system for monitoring the structural condition of a helicopter rotor assembly component includes a piezoelectric sensor. Acoustic emission signal techniques allow for recognizing the relatively high frequency stress waves associated with the propagation of cracks or defects in a rotor assembly component. A signal conditioner processes the sensor signal and provides an output signal that includes at least one characteristic that is indicative of the content of the sensor signal and, therefore, the structural condition of the item of interest. A signal analyzer utilizes the output signal from the signal processor to determine the structural condition of the component.

Abstract: A forage harvester represents agricultural implements that include at least one rotating component which is driven through a drive train including a main clutch operable between engaged and disengaged conditions so as to selectively couple and disconnect an output of the implement power source with the rotatable component. A rotation alarm circuit is provided for causing a warning device or devices to be energized in the event that the operator leaves a seat, in which he sits for normal operation, for a predetermined minimum time period while the rotatable component is still rotating, as determined by a rotation sensor. The warning device will remain energized until the rotatable component spins down to a zero speed.

Abstract: A rotary signal coupler for providing signal coupling to a Surface Acoustic Wave (SAW) device (4) mounted on a shaft (5) comprises a first electrically conducting loop (21) mounted on a disc (23) and connected to the SAW device (4), and a second electrically conductive loop (22) mounted on a disc (24) and connected to external electronic circuitry. The disc (23) is fixed relative to the shaft (5) and the disc (24) is fixed relative to the structure in which the shaft (5) rotates so that the loops (21, 22) are inductively coupled. A grounded screen (27), which preferably takes the form of a plurality of radially extending fingers, is located on the disc (23) and positioned between the loops (21, 22) to eliminate capacitive coupling therebetween.

Abstract: A sensor (36) for monitoring rotation of an object (16) about an axis (20) comprises a switch member (40) that is urged into a neutral position and is movable relative to the object (16). A direction of movement of the switch member (40) relative to the object (16) is indicative of a direction of rotation of the object (16). Inertia of the switch member (40) during initial rotation of the object (16) results in relative movement of the switch member (4) away from the neutral position. Centrifugal force during object (16) rotation further enhances the relative movement of the switch member (40). The sensor (36) also comprises a device (56) for monitoring a direction of movement of the switch member (40) and for providing a signal indicative thereof.

Abstract: The golf club has a head and a shaft. A three axis linear accelerometer is mounted on the shaft adjacent to the head. The axis of one accelerometer is in parallel alignment with an axis of the shaft. A circuit board is attached to the shaft and the accelerometer. The circuit board includes a calibrator for calibrating at least the accelerometer with an axis parallel to the axis of the shaft. The circuit board also has a wireless transmitter. Data from the accelerometer is transferred to a processor by the transmitter. The measured velocity of the club head is displayed by a display device carried by the golfer.

Abstract: A pedal stroke sensor a rotor that rotates with a brake pedal with a pair of brushes fixed on the rotor. The brushes are inclined oppositely to each other along rotating direction of the rotor and contact a circuit printed on a circuit board to generate output voltages V1A and V1B which increase and decrease oppositely to each other in response to the brushes sliding over the circuit board. A difference signal |V1A−V1B| is output as a signal corresponding to pedal stroke S of the brake pedal. When any kind of vibration changes the contacting positions of the brushes on the board, the output voltages V1A, V1B change in the same direction, so that, even if the contacting positions of the brushes change because of a vibration, the difference signal |V1A−V1B| does not change greatly, allowing accurate detection of the position of the brake pedal even if such vibrations occur.

Abstract: A detector for detecting a rotational angle of a gearshift lever. The detector includes a magnet that forms a magnetic flux in a predetermined direction along its surface. A magnetic resistance sensor generates a detection signal corresponding to the direction of the magnetic flux. The detected object is connected to the magnet or the magnetic resistance sensor. The magnet and the magnetic resistance sensor are rotated relatively to each other to generate the detection signal and obtain the rotational angle of the detected object. The magnetic resistance sensor is separated from an axis of rotation of the sensor or the magnet.

Abstract: A method of determining the angular position of the steering wheel of a motor vehicle using an optoelectronic steering angel sensor includes disposing a code transmitter between the light source and the line sensor. The line sensor has image points positioned along a line at equal intervals with respect to one another. The line sensor is operable for generating light signals as a function of the position and intensity of light traces imaged onto the image points of the line sensor. The code transmitter concentrically surrounds a steering spindle of a steering wheel of a motor vehicle and is fixed to the steering spindle to rotate therewith. The code transmitter has a scanning line and a reference line for respectively imaging a scanning light trace and a reference light trace from the light source onto the image points of the line sensor.

Abstract: A method of identifying a direction of rotation of a wheel using Hall probes which are disposed about the circumference of the wheel. In this case, a first, a second and a third Hall probe are disposed successively, so that the second Hall probe lies between the first and third Hall probes. From the output signals of the three Hall probes, two evaluation signals are obtained, through comparison of which the direction of rotation of the wheel is determined.

Abstract: A sensor is positioned to sense the magnetic field strength of a magnet associated with a rotating body. The sensor produces a signal having a sinusoidal output as the magnet rotates with the rotating body. A controller takes a derivative of the output and calculates the rotational velocity of the rotational body as a function of the derivative.

Abstract: A position and speed sensor comprising a circular element (1) rotatably driven about its axis. The circular element (1) has two position indicators (3, 4) of different angular width. A sensor means (5) is fixed in position with respect to and adjacent to the circular element (1). The sensor means (5) has a sensing element for sensing the passage of each of the position indicators (3, 4) past the sensing clement. An electrical signal is produced by the sensor means (5) corresponding to the passage of each of the sensed position indicators (3, 4). The signal has a duration corresponding to the angular widths of the sensed position indicators (3, 4). Also included is a means to process the electrical signal to produce information as to the angular position and angular velocity of the circular element. A method for reverse rotation detection using the position and speed sensor means (5) is also disclosed.

Abstract: A rotary apparatus in which at least one electrically controlled device is attached to a rotor. The rotor carries coils such that rotation of the rotor generates power for the device. A switch is provided for controlling the supply of power to the device and receives control signals via a contactless communication link.

Abstract: A first value (V), which corresponds to the angular units covered during two actual position values successively transmitted via the data transmission link at the maximum rotational speed of the encoder shaft (W), and a second value (D) which corresponds to the difference between the maximum travel of the angular position encoder (MAX) and the first value (V), are stored in a store. A processing unit determines the direction of rotation of the shaft (W) depending on whether two actual position values (X11, X12; X21, X22; X31, X32) lie in the range between the zero point (NP) of the angular position encoder and an actual position value (L2) corresponding to the magnitude of the first stored value (V), or in the range between an actual position value (L1) corresponding to the magnitude of the second stored value (D) and the maximum travel (MAX), or outside these ranges.

Abstract: A position indicator for a rotary valve actuator has a stator of one color mountable on a housing for the actuator and a rotor of a contrasting color which is connected to the actuator output shaft for rotation with it. The rotor has inner and outer coaxial cylindrical walls with windows in the outer wall. The stator has a hollow cylindrical wall in the space between the rotor walls. When the windows of the rotor and stator are in registration the inner wall of the rotor is visible and the stator is hidden to indicate one position of the actuator output shaft. When the windows of the rotor and stator are out of registration the inner wall of the rotor is hidden by the stator wall which is visible through the rotor window to indicate another position of the actuator output shaft. A circuit actuator and sensor may be mounted on the rotor and stator for generating electrical signals indicative of the actuator output shaft position in addition to the visual indication.

Abstract: A method and system for detecting faults with a self-exciting sensor includes a monitor circuit coupled to the self-exciting sensor for monitoring a signal associated with the sensor and generating a failure signal. A voltage limiting circuit is coupled to a receiver circuit associated with the self-exciting sensor for generating a first output signal within a valid range of operation in the absence of the failure signal. The voltage limiting circuit also generates a second output signal outside the valid range of operation in response to the failure signal so as to eliminate the necessity of an additional input to control logic associated with the self-exciting sensor.

Abstract: An infinitely adjustable position sensor is provided. The position sensor can be used as a head position switch which generates an output indicative of a position of a harvesting head of a harvesting vehicle, or in similar applications with other types of equipment. The sensor includes a body attachment mechanism for coupling the sensor to the body of the vehicle or other equipment, and a head attachment mechanism for coupling the sensor to the feeder house which supports the harvesting head. For adjustment of the sensor, particularly prior to operation, visual feedback is provided by an LED ring in order to inform the operator of the state or position of the sensor.

Abstract: To accurately detect a resonance frequency of tire even in high speed range by which tire air pressure state of each wheel is known, a calculation processing unit to which detection signals of wheel speed and resonance frequencies of tire are inputted calculates a timewise change amount of a wheel speed deviation that is a difference between wheel speed ratios of front and rear wheels. Then, it makes corrections to remove the influence of timewise change amounts of resonance frequencies of front wheels from timewise change amounts of wheel speed deviations based on a relationship between the resonance frequency and the wheel speed deviation when air pressure of the tire is changed.

Abstract: An apparatus is provided to determine the speed and direction of a rotating shaft, including a rotor with three circumferentially spaced teeth connected to the shaft. The spacing of the center of the second rotor tooth is wider than the spacing of the center of the first tooth and the spacing of the center of the third tooth is wider than the spacing of the center of the second tooth. A sensor detects the center of each tooth and produces a signal in response thereto. The signal is received by a computer. The computer determines the speed and direction of rotation of the shaft by determining a first time period to reach the center of the first tooth, a second time period to reach the center of the second tooth and a third time period to reach the center of the third tooth.

Abstract: A resolver rate sensor is disclosed in which dual brushless resolvers are mechanically coupled to the same output shaft. Diverse inputs are provided to each resolver by providing the first resolver with a DC input and the second resolver with an AC sinusoidal input. A trigonometric identity in which the sum of the squares of the sin and cosine components equal one is used to advantage in providing a sensor of increased accuracy. The first resolver may have a fixed or variable DC input to permit dynamic adjustment of resolver sensitivity thus permitting a wide range of coverage. In one embodiment of the invention the outputs of the first resolver are directly inputted into two separate multipliers and the outputs of the second resolver are inputted into the two separate multipliers, after being demodulated in a pair of demodulator circuits. The multiplied signals are then added in an adder circuit to provide a directional sensitive output.