Abstract: An apparatus and method derives a deformation amount of a contact-portion of the tire based on the tire information, the contact-portion being in contact with the ground, and calculates an evaluation value based on the derived deformation amount, and comparing the calculated evaluation value with a reference value to determine whether or not the internal mechanical failure has occurred in the tire.

Abstract: The apparatus acquires acceleration data in time series at a fixed position of a tire while a vehicle having the tire is traveling on a road surface, obtains a spectrum of the acceleration by subjecting the acquired time series acceleration data to frequency analysis, and detects a peak value of the spectrum of the acceleration in a frequency range of 500 Hz-1500 Hz. The apparatus evaluates a degree of a safety in traveling of the vehicle according to the detected peak value. The acceleration data is acquired by an acceleration sensor mounted on the fixed position of the tire.

Abstract: Provided is a non-pneumatic tire in which buckling can be prevented without a weigh increase of the tire, the non-pneumatic tire including a spoke structure. The non-pneumatic tire is characterized in that, in the non-pneumatic tire where a spoke structure obtained by circumferentially arranging spokes intermittently at intervals, which radially couple together annular cylindrical outer member and cylindrical inner member, is joined to an inner peripheral side of a tread ring, at least some of a plurality of spaces each formed between two spokes adjacent to each other in the tire circumferential direction each have an air-containing structure.

Abstract: A wheel attitude control method of the invention comprises the steps of: chronologically obtaining acceleration data in a radial direction of a tire at a center position of a tire tread and at an off-center position spaced apart from the center position toward a shoulder; obtaining respective contact lengths at the center position and the off-center position from the acceleration data; and controlling a wheel attitude, which varies in accordance with changes in a load applied to the wheel when the braking force is imparted to the wheel, based on the obtained contact length at the center position and the obtained contact length at the off-center position.

Abstract: A method of calculating deflection of a rotating tire, through high speed data processing, based on measurement time series data of acceleration on a tire tread portion has the following steps. A step of acquiring measurement time series data of acceleration on a tire circumference in a radial direction of a rotating tire; a step of extracting acceleration data in a vicinity of a contact region from the acquired measurement data and subjecting the extracted acceleration data to least-square regression using a second-order differential function expression of a deflection function expression that represents a peak shape having a peak value and a curve gradually approaching to zero on both sides thereof, whereby a deflection function parameter values are determined; and a step of calculating a contact deflection from the deflection function expression determined by the deflection function parameter values.

Abstract: An acceleration sensor-attached tire is provided which can detect acceleration in one arbitrary direction, in two or more directions where vectors are linearly independent of each other, or in two or more directions where vectors of the detected acceleration cross each other generated in a tire in a practical velocity range. A sensor unit 100 is embedded inside a tire, and the acceleration in three directions crossing each other and generated in the tire 300 is detected by an acceleration sensor provided in this sensor unit, and the detected acceleration is transmitted. The acceleration sensor is a micro electro mechanical systems (MEMS) type sensor and comprises a semiconductor acceleration sensor.

Abstract: A method of calculating a cornering force to be applied to each wheel provided to a vehicle which is cornering, comprising the steps of: obtaining a magnitude of a centrifugal force to the vehicle in a direction substantially orthogonal to a vehicle traveling direction, a contact length of each wheel during the cornering of the vehicle, and an amount of deformation in a wheel width direction at the contact portion of each wheel of the vehicle, calculating a difference between the obtained amount of the deformation and an amount of deformation in the wheel width direction under a straight forward travel condition of the vehicle for each wheel, and calculating a cornering force for each wheel based on the magnitude of the centrifugal force, the contact length, and the difference between amounts of deformation in the wheel width direction.

Abstract: An apparatus and method acquires acceleration data in a time series of a predetermined site of the tire during traveling of the vehicle, and removes an acceleration component due to a deformation of the tire from the acquired acceleration data to obtain a modified acceleration data, and performs frequency analysis of the modified acceleration data to obtain a frequency spectrum, and obtains an accumulated value of the frequency spectrum, and calculating a braking distance parameter for predicting a braking distance based on the obtained accumulated value, and obtains a predicted value of the braking distance of the vehicle based on the braking distance parameter calculated in the calculating part.

Abstract: A method and apparatus derives a change amount in the cumulative value of displacement for the unit of time as a change ratio in tire deformation by using the cumulative value of displacement derived present time and the cumulative value of displacement derived last time, and calculate a rate of change ratio using the change ratio in tire deformation previously calculated as a reference value and the change ratio calculated present time, and determine a cornering stability of the wheel that represents a degree of a margin in which the wheel keeps no sliding and beyond which the wheel start sliding based on the rate of change ratio.

Abstract: A brake control device includes a braking device provided to a wheel, the braking device having a function of applying a brake force to the wheel while adjusting the brake force. The brake control device includes: an acceleration sensor for outputting acceleration data of acceleration acting on the rotating tire in a radial direction of the tire; a contact length calculating unit for calculating contact lengths of the tire based on the acceleration data; a brake sensor for detecting that a brake force is applied and for outputting a detection signal; a judging unit for outputting, to the braking device, a brake information signal for adjusting the brake force according to comparative judgment information which is obtained by comparing the calculated contact lengths; and a brake control unit for outputting a control signal for causing the braking device to adjust a brake force thereof according to the brake information signal.

Abstract: A brake control device is provided to a wheel equipped with a tire, which has a function of applying a brake force to the wheel to put a brake thereon while adjusting the brake force. In the device, an acceleration sensor outputs acceleration data in a radial direction of the rotating tire, a predetermined detection range is set with respect to the acceleration data, a threshold value is set with respect to a corresponding part of the acceleration data falling within the detection range, the corresponding part of the acceleration data falling within the detection range is specified. Values of the specified acceleration data are compared with the threshold value, and a control signal for causing a braking device to adjust the brake force thereof is output in a case where some values of the acceleration data are larger than the threshold value.

Abstract: A deformation of a rotating tire on a road surface is calculated the following. At first, time series data of acceleration extracted from measurement data of acceleration corresponding to one round of tire rotation is subjected to a time integration of second order to obtain displacement data so as to calculate the deformation at the tread portion. The time series data of acceleration and the displacement data in the non-contact region excluding a road surface contact region on the tire circumference at the tread portion are respectively approximated to calculate a first and a second approximation curves. The two approximation curves are subtracted respectively from the time series data of acceleration and the calculated displacement data, thereby extracting time series data of acceleration due to tire deformation and obtaining the deformation at the tread portion.

Abstract: To provide a non-pneumatic tire, including a spoke structure, which can be easily mounted on a rim of a wheel. In addition, to provide a non-pneumatic tire whose durability is improved by suppressing the buckling of a spoke structure. [Solving Means] Provided is a non-pneumatic tire including a spoke structure (5) and a tread ring (11). The spoke structure (5) includes a cylindrical outer member (2) and a cylindrical inner member (3) which are concentrically arranged, and which are connected to each other with a plurality of fins (4, 4?) arranged in between at intervals in the circumferential direction. The tread ring (11) is fitted onto the outer periphery of the spoke structure (5). In the pneumatic tire, the spoke structure (5) is divided in the tire circumferential direction into at least two circumferential-direction separate structures (511, 521, 531).

Abstract: The apparatus acquires acceleration data in time series at a fixed position of a tire while a vehicle having the tire is traveling on a road surface, obtains a spectrum of the acceleration by subjecting the acquired time series acceleration data to frequency analysis, and detects a peak value of the spectrum of the acceleration in a frequency range of 500 Hz-1500 Hz. The apparatus evaluates a degree of a safety in traveling of the vehicle according to the detected peak value. The acceleration data is acquired by an acceleration sensor mounted on the fixed position of the tire.

Abstract: Provision is made for an acceleration detection method and a device therefor, an acceleration sensor module, and a tire with which high-accuracy detection of acceleration can be implemented over the whole detection range.

Abstract: A deformation of a rotating tire on a road surface is calculated the following. At first, time series data of acceleration extracted from measurement data of acceleration corresponding to one round of tire rotation is subjected to a time integration of second order to obtain displacement data so as to calculate the deformation at the tread portion. The time series data of acceleration and the displacement data in the non-contact region excluding a road surface contact region on the tire circumference at the tread portion are respectively approximated to calculate a first and a second approximation curves. The two approximation curves are subtracted respectively from the time series data of acceleration and the calculated displacement data, thereby extracting time series data of acceleration due to tire deformation and obtaining the deformation at the tread portion.

Abstract: To detect a slip state in a contact region of a rotating tire on a road surface, first, the first radical direction data and the second width direction data of measurement data of acceleration at a tread portion of the rotating tire for a duration corresponding to one round of tire rotation are acquired. Second, time series data of acceleration due to tire deformation is extracted from the first radical direction data and displacement data is obtained by subjecting the time series data of acceleration due to tire deformation to a time integration of second order, thereby a deformation at the tread portion is calculated and a contact region of the rotating tire is determined from the calculated deformation. Next, from the second width direction data, a slip region within the determined contact region is specified based on vibration level of the second data.

Abstract: An apparatus and method acquires acceleration data in a time series of a predetermined site of the tire during traveling of the vehicle, and removes an acceleration component due to a deformation of the tire from the acquired acceleration data to obtain a modified acceleration data, and performs frequency analysis of the modified acceleration data to obtain a frequency spectrum, and obtains an accumulated value of the frequency spectrum, and calculating a braking distance parameter for predicting a braking distance based on the obtained accumulated value, and obtains a predicted value of the braking distance of the vehicle based on the braking distance parameter calculated in the calculating part.

Abstract: An apparatus and method derives a deformation amount of a contact-portion of the tire based on the tire information, the contact-portion being in contact with the ground, and calculates an evaluation value based on the derived deformation amount, and comparing the calculated evaluation value with a reference value to determine whether or not the internal mechanical failure has occurred in the tire.

Abstract: A method and apparatus derives a change amount in the cumulative value of displacement for the unit of time as a change ratio in tire deformation by using the cumulative value of displacement derived present time and the cumulative value of displacement derived last time, and calculate a rate of change ratio using the change ratio in tire deformation previously calculated as a reference value and the change ratio calculated present time, and determine a cornering stability of the wheel that represents a degree of a margin in which the wheel keeps no sliding and beyond which the wheel start sliding based on the rate of change ratio.