A tire revolution direction determination system includes a detection device arranged in each of two tires coupled back-to-back and a monitoring unit. The detection device includes a first detector that detects a first acceleration in a tire diameter direction and a second detector that detects a second acceleration in the tire diameter direction. The first detector is arranged in front of the second detector in a reference direction. When the monitoring unit receives the first acceleration and the second acceleration from the detection device while a vehicle travels forward, it specifies change over time of the first acceleration and change over time of the second acceleration and determines whether a direction of revolution of the tire where the detection device is arranged is the reference direction based on whether change over time of the first acceleration is more advanced than change over time of the second acceleration.

A vehicle-mounted system provided in a vehicle including a tire includes a detector attached to the tire, the detector transmitting a detection signal, and a monitoring unit that determines a position of the tire based on a plurality of detection signals received from the detector. The detector determines a direction of revolution of the tire, and when the detector determines that the direction of revolution of the tire has changed, it switches a frequency of transmission of the detection signal from a first frequency to a second frequency higher than the first frequency.

A method of sensing wheel rotation can include: sensing magnetic force information in an environment of a wheel by a magnetometer to obtain measured magnetic force information; generating relative magnetic force information by performing mathematical operation processing in accordance with the measured magnetic force information, where the relative magnetic force information does not change with geomagnetic field and does change with a rotation angle of a wheel; and obtaining angle information related to the rotation angle of the wheel in accordance with the relative magnetic force information.

A wear amount estimation method calculates a shearing force of each rib based on an average grounding pressure of each rib of an aircraft tire; calculates a wear energy of the aircraft tire based on the shearing force; and estimates the wear amount of the aircraft tire based on the wear energy and a wear resistance showing a relationship between a predetermined wear amount. The information related to the aircraft includes an internal pressure of the aircraft tire. The average grounding pressure of each rib is calculated based on the internal pressure and a wheel load applied to the aircraft tire.

A method of determining a left or right side installation position of a trailer wheel of a trailer connected to a tow vehicle. A number of rotations of the trailer wheel is determined using an acceleration sensor, and a number of rotations of a left side tow vehicle wheel and a right side tow vehicle wheel is determined using an ABS sensor or ESP sensor of the left side tow vehicle wheel and the right side two vehicle wheel, respectively. A first correspondence value between the number of rotations of the trailer wheel and the number of rotations of the left side tow vehicle wheel is determined. A second correspondence value between the number of rotations of the trailer wheel and the number of rotations of the right side tow vehicle wheel is determined. A left side or right side installation position of the trailer wheel is determined based on the first correspondence value and the second correspondence value.

A reception control section obtains the rotation angles of wheel assemblies when receiving transmission data by a reception circuit. The reception control section divides 360°, which is the range of the possible rotation angles of the wheel assembly, into equal parts to obtain angle ranges and assigns each of the obtained rotation angles to one of angle ranges. The reception control section derives the angle range in which the number of times (frequency) the obtained rotation angles are included is a maximum value. The reception control section calculates a reception-side angle difference, which is the difference between the median values of the angle ranges in which the number of times the obtained rotation angle is included is a maximum value. The reception control section associates the ID codes with the wheel assemblies based on the correspondence between the reception-side angle difference and the angle difference between specific angles.

A method of sensing wheel rotation can include: sensing magnetic force information in an environment of a wheel by a magnetometer to obtain measured magnetic force information; generating relative magnetic force information by performing mathematical operation processing in accordance with the measured magnetic force information, where the relative magnetic force information does not change with geomagnetic field and does change with a rotation angle of a wheel; and obtaining angle information related to the rotation angle of the wheel in accordance with the relative magnetic force information.

A wheel registration apparatus applied to a vehicle comprises: a transmitter that is provided on each of the four traveling wheels provided with tires and has a first controller configured to create and transmit a frame including unique identification information; and a receiver that is provided on a vehicle body, receives the frames transmitted by the transmitters provided on the four traveling wheels via a reception antenna in a registration mode, and has a second controller configured to register four pieces of the identification information included in the respective frames as pieces of identification information of the transmitters provided on current four traveling wheels.

An apparatus and method for measuring pressure and/or humidity, having at least one sensor for measuring pressure and/or humidity. The sensor has at least one capacitor having at least two electrodes that are arranged in a horizontal direction relative to one another along and on a flexible support material. At least one dielectric layer is arranged between the electrodes. At least one at least partially moisture-permeable and/or moisture-absorbing layer is arranged in some places on a side, facing away from a support material, of the electrode and/or the dielectric layer. The at least one electrode and/or the dielectric layer are arranged transversely between the support material and the moisture layer. In this way, a capacitance is at least partially changed by moisture hitting the dielectric layer, and a processing unit is designed and provided to measure and/or store this change, so as to create a capacitive moisture sensor.

The present disclosure provides a method for monitoring a motion status of a vehicle, a related chip, and a system. The method includes: obtaining N acceleration values in a first axial direction collected from N times sampling and a maximum acceleration change value within a preset time period; and obtaining N acceleration values in a second axial direction collected from N times sampling and a maximum acceleration change value within the preset time period; determining whether the vehicle is in motion or in a first stationary state based on the acceleration values in the first and second axial direction; and in response to the vehicle being in the first stationary state, further determining whether the vehicle is in motion or in a second stationary state based on the maximum acceleration change values in the first and second axial direction.