Tire position determination system

A tire position determination system comprising:

• transmitters respectively coupled to tires, wherein each of the transmitters is capable of transmitting a first radio wave signal that includes pressure data and a tire ID;
• rotation detectors respectively arranged on axles, wherein each of the rotation detectors detects rotation of a corresponding one of the axles and generates axle rotation information;
• and
• a receiver arranged on a vehicle body, wherein the receiver is capable of receiving the first radio wave signal transmitted from each of the transmitters, wherein
• each of the transmitters includes:
• a controller that detects that the transmitter has reached a specific position on a rotation path of the tire, and
• the controller generates a second radio wave signal, which includes an ID and data indicating that the transmitter has reached the specific position on the rotation path of the tire, based on a detection result detected by the controller and transmits the second radio wave signal from the transmitter, and
• the receiver includes:
• a processor that acquires the axle rotation information from each of the rotation detectors whenever the receiver receives the second radio wave signal, and
• the processor calculates a distribution of the axle rotation information for each of the IDs by collecting statistics of the axle rotation information for each of the IDs and determines tire positions of the tires by specifying an ID of a tire that rotates in synchronism with the axle rotation information of each of the axles based on the distribution,
• wherein the processor performs absolute evaluation, which determines validity of the distribution using the axle rotation information of each of the axles, and relative evaluation, which determines validity of the distribution using the axle rotation information of the axles, to determine a tire position based on a result of the absolute evaluation and a result of the relative evaluation.

A tire position determination system comprising:

• transmitters respectively coupled to tires, wherein each of the transmitters is capable of transmitting a first radio wave signal that includes pressure data and a tire ID;
• rotation detectors respectively arranged on axles, wherein each of the rotation detectors detects rotation of a corresponding one of the axles and generates axle rotation information;
• and
• a receiver arranged on a vehicle body, wherein the receiver is capable of receiving the first radio wave signal transmitted from each of the transmitters, wherein
• each of the transmitters includes:
• a controller that detects that the transmitter has reached a specific position on a rotation path of the tire, and
• the controller generates a second radio wave signal, which includes an ID and data indicating that the transmitter has reached the specific position on the rotation path of the tire, based on a detection result detected by the controller and transmits the second radio wave signal from the transmitter, and
• the receiver includes:
• a processor that acquires the axle rotation information from each of the axle rotation detectors whenever the receiver receives the second radio wave signal, and
• the processor calculates a distribution of the axle rotation information for each of the IDs by collecting statistics of the axle rotation information for each of the IDs and determines tire positions of the tires by specifying an ID of a tire that rotates in synchronism with the axle rotation information of each of the axles based on the distribution,
• wherein, when a tire position of a tire of a specific ID is not specified, and a plurality of candidate tires remain, and when a tire position of a tire of another ID is specified, the processor deletes the specified tire from the plurality of candidate tires and narrows down or specifies a correct tire.