Abstract: Auto-location systems and methods of tire pressure monitoring sensor units arranged with a wheel of a vehicle detect a predetermined time (T1) when a wheel phase angle reaches angle of interest using a rim mounted or a tire mounted sensor. The systems and methods transmit a radio frequency message associated with a wheel phase angle indication. The wheel phase angle indication triggers wheel phase and/or speed data such as ABS data at the predetermined time (T1) to be stored. A correlation algorithm is executed to identify the specific location of a wheel based on the wheel phase and/or speed data at the predetermined time (T1). TPM sensor parameters from a tire pressure monitoring sensor unit are assigned to the specific location of the wheel based on a confidence interval width analysis of the ABS data at the predetermined (T1).

Abstract: Methods, systems, and devices are provided for tire pressure detectors that may operate according to one of two or more selectable frequencies. Tire pressure detectors may include an RF section to modulate pressure information from a pressure sensor onto an output signal. The frequency of the output signal may be selectable from two or more frequencies based on a frequency required by a vehicle that the tire pressure detector is to be used with. An RF matching circuit may be coupled between the RF section and an antenna, with an impedance of the RF matching circuit selected based of the frequency of the output signal. Such impedance matching may provide a constant power level output from the tire pressure detector independent of the frequency of the tire pressure detector transmissions.

Abstract: A pressure regulator valve has a housing that defines a fluid passage and a flat seat disposed around an opening of the fluid passage and exit ports. A pin with a raised conforming elastomeric embossment that contacts the seat when the valve is closed is axially disposed in the housing. The pin is biased to maintain the elastomeric embossment in contact with the seat to maintain the valve closed and control an opening pressure of the valve. Flow of fluid through and out of the pressure regulator valve housing is controlled through adjustment of a level of this biasing. The fluid flows across the flat seat and between the flat seat and the embossment when the valve is open in such a manner that the flow is generally laminar and such that the valve minimizes pressure gain at the onset of flow.

Abstract: A method for determining change of direction of a vehicle includes steps of maintaining a rolling window of ABS data indicative of ABS tooth count and capturing a relevant rolling window of ABS data at the predetermined one-measurement point; storing the rolling window of the ABS data indicative of ABS tooth in a buffer; monitoring the ABS data and detecting a valid stop event which causes the rate of change of ABS tooth count to substantially decrement to zero; and monitoring the ABS data and detecting a valid move event which causes the rate of change of ABS tooth count to substantially increment from zero.

Abstract: A method for determining change of direction of a vehicle includes steps of maintaining a rolling window of ABS data indicative of ABS tooth count and capturing a relevant rolling window of ABS data at the predetermined one-measurement point; storing the rolling window of the ABS data indicative of ABS tooth in a buffer; monitoring the ABS data and detecting a valid stop event which causes the rate of change of ABS tooth count to substantially decrement to zero; and monitoring the ABS data and detecting a valid move event which causes the rate of change of ABS tooth count to substantially increment from zero.

Abstract: A TPM system wheel unit measures rotational period over a number of wheel revolutions, calculates a value of a period of the revolutions and wirelessly transmits the calculated value of the period to a tire pressure monitoring system receiver in the vehicle mounting the wheel. Alternatively, each wheel unit transmits an RF burst of a predetermined length and a received RF burst envelope modulated with a periodic modulation pattern is used to calculate the period of one wheel rotation for each wheel. A central vehicle electronic control unit monitors wheel speed signals for each wheel of the vehicle and calculates a period for the wheel speed signal for each wheel of the vehicle, bounded by a rolling window which may be of variable length. The calculated values are compared and the wheel unit and the wheel location are correlated therefrom.

Abstract: Power transmission monitoring systems includes rotation speed sensors mounted to hubs of a power transmission pulley. A sensor comprises a rotation sensing device, and a controller receiving rotation data therefrom and determining rotation speed of the pulley. A transmitter transmits rotational speed of the pulley to a receiver, which may include or be connected to a device that compares the rotational speed to rotational speed in transmissions from other sensors to determine slip in the power transmission system. The rotation speed sensing device may be an accelerometer, or a gravitational torque harvester. A harvester might include a rotor body rotating with the pulley and mounting induction coils, and a gravitational torque stator mounting an induction magnet and including an air vane damper maintaining the stator stationary with respect to the rotor, through air resistance. The transmissions may be employed to monitor, maintain and repair the power transmissions system.

Abstract: A method carried out in a wheel unit of a tire pressure monitoring system comprises detecting, using a controller in the wheel unit, increases and decreases in loading of a tire on a wheel associated with the wheel unit during acceleration and deceleration. Front/rear position of the wheel unit on a vehicle mounting the tire pressure monitoring system is determined, using the controller in the wheel unit, based on the loading and unloading of the tire and wheel during acceleration and deceleration. Rotation direction of the wheel in the wheel unit is determined and the controller in the wheel unit determines left/right position of the wheel unit on the vehicle based on the rotation direction of the wheel. An indication of the front/rear and left/right position of the wheel on the vehicle and an identification unique to the transmitting wheel unit are transmitted.

Abstract: A wheel position determination system and method to count wheel revolutions in a wheel unit of a tire monitoring system. An indication of the count is transmitted, optionally along with an indication of a left/right side position of the wheel on the vehicle, and an identification unique to the transmitting wheel unit, to a central controller of the tire monitoring system. In the central controller of the tire monitoring system, the count is compared with wheel speed information for the vehicle, such as from an ABS system, to determine if one wheel on each side of the vehicle is rotating at a different speed. Based at least in part upon a determination that each wheel speed is unique, a determination of wheel location may be made.

Abstract: An automotive urea solution monitoring device is deployed in conjunction with the urea tank of a selective catalytic reduction vehicle. An RF signal of a constant frequency may be generated across a resonant circuit, which may be comprised of an inductor and a PCB trace capacitor, or the like. Electromagnetic radiation is propagated into the automotive urea solution in the urea tank. The conductivity and dielectric properties of the liquid change the impedance of the discrete/trace capacitor and or the discrete/trace inductor. These changes are proportional to ammonia content, temperature, and/or level of the automotive urea solution in the urea tank and are preferably detected by a microcontroller, or the like, and then transmitted to a selective catalytic reduction vehicle engine management system, or the like.

Abstract: Auto-location systems and methods of tire pressure monitoring sensor units arranged with a wheel of a vehicle detect a predetermined time (T1) when a wheel phase angle reaches angle of interest using a rim mounted or a tire mounted sensor. The systems and methods transmit a radio frequency message associated with a wheel phase angle indication. The wheel phase angle indication triggers wheel phase and/or speed data such as ABS data at the predetermined time (T1) to be stored. A correlation algorithm is executed to identify the specific location of a wheel based on the wheel phase and/or speed data at the predetermined time (T1). TPM sensor parameters from a tire pressure monitoring sensor unit are assigned to the specific location of the wheel.

Abstract: Auto-location systems and methods of tire pressure monitoring sensor units arranged with a wheel of a vehicle detect a predetermined time (T1) when a wheel phase angle reaches angle of interest using a rim mounted or a tire mounted sensor. The systems and methods transmit a radio frequency message associated with a wheel phase angle indication. The wheel phase angle indication triggers wheel phase and/or speed data such as ABS data at the predetermined time (T1) to be stored. A correlation algorithm is executed to identify the specific location of a wheel based on the wheel phase and/or speed data at the predetermined time (T1). TPM sensor parameters from a tire pressure monitoring sensor unit are assigned to the specific location of the wheel.

Abstract: Systems and methods for auto-location of tire pressure monitoring sensor units on a vehicle measure the angle of a wheel at two different times using a rim mounted or a tire mounted sensor and determines a difference in measured angles. The systems and methods provide for transmitting the angles and/or the difference in the measured angles along with a sensor identification to an electronic control module. Alternatively, the systems and methods provide for transmitting time differences to the electronic control module. The electronic control module correlates information transmitted from the wheel unit with antilock brake system data. A location of the wheel mounting the sensor is determined and the sensor identification is assigned.

Abstract: A pressure sensing device, such as a tire pressure monitoring unit comprises a pressure sensor for measuring pressure of a fluid, such as air or an inert gas, in an environment external to the device, such as within the cavity of a tire. A hollow resonator, or standing wave tube, is coupled to the pressure sensor. The resonator has a free end exposed to the external environment to the extent that pressure variations in the fluid are propagated through the hollow resonator to the pressure sensor via the free end. The hollow resonator has a resonant frequency substantially matching a target frequency such that resonance is established in the tube at the resonant frequency in response to the presence of an audio signal in the fluid having a frequency that substantially matches the target frequency.

Abstract: Methods for detecting and correcting data errors in an RF data link include identifying valid data frames and corrupted data frames by measuring a data corruption level for each transmitted data frame, comparing the measured data corruption level for each corrupted data frame to a data corruption threshold, reconstructing the corrupted data frames having a data corruption level below the data corruption threshold, reconstructing the data block using data from valid and reconstructed data frames, and/or verifying the data in the reconstructed data block.

Abstract: A wheel position determination system and method to count wheel revolutions in a wheel unit of a tire monitoring system. An indication of the count is transmitted, optionally along with an indication of a left/right side position of the wheel on the vehicle, and an identification unique to the transmitting wheel unit, to a central controller of the tire monitoring system. In the central controller of the tire monitoring system, the count is compared with wheel speed information for the vehicle, such as from an ABS system, to determine if one wheel on each side of the vehicle is rotating at a different speed. Based at least in part upon a determination that each wheel speed is unique, a determination of wheel location may be made.

Abstract: In a liquid sensing system, an RF signal is applied to a series-resonant circuit. The coil of the resonant circuit is placed proximate to a fuel tank, causing electromagnetic radiation to propagate into the fuel space. The fuel acts as an electrical load to the resonant circuit in a manner proportionate to the volume of fuel in the tank and/or to variations in electrical properties of the fuel itself. The loading effect of the fuel can change the resonant frequency and/or the Q of the resonant circuit. The loading effect of the fuel is determined by monitoring a change in one or more electrical parameters associated with the excited resonant circuit, such as a voltage across the resistor in the resonant circuit. Changes in this voltage are analyzed by a controller, the result of which is used to output a value indicative of level and/or composition of the fuel.

Abstract: A tire monitor system includes a tire monitor sensor unit that has a tire pressure detector, a coupler and a tire valve. The tire valve operates as an antenna to transmit tire data from the tire pressure detector. The coupler provides a capacitive coupling that removably couples the tire pressure detector and the tire valve. The coupler includes two metal layers separated by a dielectric layer. The two metal layers may be formed by the tire valve and a connection tube.

Abstract: A flex fuel sensor is deployed in conjunction with the fuel transfer line (e.g. around a plastic fuel line) or at the bottom/side of a fuel tank. An RF signal of a constant frequency may be generated across a resonant circuit, which comprises of an inductor and a PCB trace capacitor, capacitor plates, semi cylindrical capacitor plates, or the like. Electromagnetic radiation is propagated into the passing fuel in the transfer pipe. The conductivity and dielectric properties of the fuel change the capacitance of the trace capacitor/capacitor plates. These changes are proportional to ethanol/alcohol content of the fuel and are preferably detected by a microcontroller, or the like, and then transmitted to a flex fuel vehicle Engine Management System.

Abstract: A tire pressure detector employs a reduced power consumption mechanism comprising a PLL circuit including a VCO, that is operated in response to the logic states of an input data stream and a power amplifier configured to be externally located to an integrated circuit. The input data stream includes tire pressure information and is configured to be encoded to have multiple logic states. A micro-controller is employed to control the VCO, turning the VCO, and/or the amplifier, on and off for a certain period, according to the pattern of each data bit of the input data stream thus providing reduced current consumption. This tire pressure detector thus embodies an optimized circuit arrangement in terms of power efficiency.