A sensor module is provided that includes a magnetic sensor and a microcontroller. The magnetic sensor is configured to measure a magnitude of a magnetic field component of an Earth magnetic field projected on a sensing axis of the magnetic sensor and is configured to generate a measurement signal. The magnetic sensor is configured to rotate about an axis through the Earth magnetic field such that the measurement signal oscillates between a first and second extremas as the magnitude of the magnetic field component projected onto the sensing axis changes due to rotation of the magnetic sensor about the axis. The microcontroller is configured to receive the measurement signal, acquire a predetermined number of measurement samples over a sampling period, calculate a variance value of the acquired measurement samples, and determine whether the magnetic sensor is rotating about the axis based on a threshold test of the variance value.

A method for monitoring a tire condition includes the following steps: sense a rotational speed of a tire of a moving vehicle via at least one monitoring device of a wireless monitoring system disposed in the vehicle; when the sensed rotational speed reaches a predetermined rotational speed range, obtain a condition of the rotating tire through at least one monitoring device to generate first condition data; compare the first condition data with a plurality of pavement feature data to obtain the corresponding pavement feature data; process with the obtained pavement feature data and the first condition data to filter a pavement feature out of the first condition data, generating second condition data; determine whether the condition of the tire is abnormal based on the second condition data; and send out a warning message when the condition of the tire is determined as being abnormal.

A method for sampling wheel acceleration, a method for determining rotation angular position of a wheel, and a tire pressure monitoring system are disclosed. The method for sampling wheel acceleration may include: acquiring a real-time wheel acceleration value of a target wheel and calculating a time length required to rotate for a preset number of revolutions of the target wheel according to a first association relationship between the wheel acceleration and the time length required to rotate for the preset number of revolutions of the target wheel; obtaining a time interval between any two adjacent sampling points according to the time length required to rotate for the preset number of revolutions; and sampling the wheel acceleration of the target wheel once every the time interval starting from any time.

A tire pressure monitoring unit is mounted on a vehicle wheel having a pressure and acceleration sensor. A method for assigning wheel positions includes pressure and acceleration data determined from the sensors. The pressure data and at least one piece of information derived from the acceleration data are transmitted wirelessly in a data telegram together with a characteristic identifier. Information concerning the reliability of the information derived from the acceleration data is acquired in the tire pressure monitoring unit on the basis of the measurements and is transmitted with the data telegram. A central evaluation unit considers a plurality of data telegrams and, taking account of data from the ABS sensors, assigns the individual tire pressure monitoring units to wheel positions. Data telegrams in which the reliability is higher receive a greater weighting, and data telegrams in which the reliability is smaller receive a smaller weighting.

A method for operating an electronic wheel unit disposed on a vehicle wheel of a vehicle includes providing the electronic wheel unit with a detecting device for detecting rotation angle positions of the vehicle wheel that are present at certain detection times, and a radio transmitter device for transmitting a sequence of individual electromagnetic signals which include data representative of the detected rotation angle positions and their associated detection times. The detecting device is further used to detect an amount of a wheel acceleration of the vehicle wheel and to set an interval of time between the detection times of the rotation angle positions to be shorter the greater the amount of wheel acceleration. A corresponding electronic wheel unit and a method and an apparatus for localizing respective installation positions of a plurality of such electronic wheel units on a vehicle are also provided.

A wheel position identifying system includes a receiver and transmitters, which are respectively provided in two wheel assemblies of a wheel assembly set. When each transmitter detects that it is located at a specific position, the transmitters transmit a wireless signal including an ID code. Receiver processing circuitry of the receiver obtains information indicating a rotation angle of the wheel assembly set from a rotation angle detecting unit of a vehicle, while associating the information with the ID code each time receiving the wireless signal from the transmitters. Based on a phase difference between rotation angles associated with different ID codes, the receiver processing circuitry identifies whether each of the transmitters is provided in a right wheel assembly or a left wheel assembly.

Aspects of tire sensor auto-location are described. Timestamped tire acceleration values are received for a set of tire sensor devices. Each tire sensor device provides a tire-specific subset of the timestamped tire acceleration values. Vehicle configuration parameters are identified to define a number of rear axles and a number of tires or wheels on each side of each axle. The vehicle configuration parameters and the timestamped tire acceleration values are processed to identify and assign an axle position and a vehicle side position for each tire sensor device of the set of tire sensor devices.

A wheel position identifying system includes a receiver and transmitters, which are respectively provided in two wheel assemblies of a wheel assembly set. When each transmitter detects that it is located at a specific position in a rotation direction of the wheel assembly, the transmitter transmits a wireless signal including an identification information. A wireless signal transmitted by the transmitter provided in the outer wheel assembly when the transmitter detects the specific position is defined as a first wireless signal. A wireless signal transmitted by the transmitter provided in the inner wheel assembly when the transmitter detects the specific position is defined as a second wireless signal. Receiver processing circuitry of the receiver identifies in which of the outer wheel assembly and the inner wheel assembly each transmitter is provided based on the reception intervals of the first wireless signal and the second wireless signal.

The present invention provides an Active Tire Auto-Location systems for tire pressure monitor sensors and an operating method. The system includes a host, wheel axle rotation detection devices and tire pressure monitor sensors. By allowing the wireless tire pressure detector to receive and compare the rotation information of a toothed ring from the wheel axle rotation detection device and the tire rotation information from the wireless tire pressure detector, each wireless tire pressure detector can identify which wheel axle rotation detection device that corresponds to it. At the same time, the tire position where each wireless tire pressure detector is situated can also be determined. Compared to prior art, it is still possible for the present invention to determine the tire position where each wireless tire pressure detector is situated, without the need for additional modification to the host, thus significantly reducing the inconvenience in replacing tire pressure monitor sensors.

This disclosure relates to a tire self-positioning system and a positioning method. The tire self-positioning method includes the steps of: S1, performing data acquisition; S2, performing data transmission; S3, performing data conversion; S4, repeatedly executing steps S1 to S3; S5, performing data statistics; S6, determining, according to a statistical result, position information of a tire corresponding to a first signal. According to the tire self-positioning system and the tire self-positioning method, the accuracy of self-positioning can be improved.