Abstract: The invention provides an apparatus, program, and method for controlling the automatic spraying of an antifreezing agent that can reduce the cost of the antifreezing agent and the impact of salt damages caused by the antifreezing agent. This is accomplished by reducing the amount of antifreezing agent to be sprayed automatically according to road surface condition and reducing the amount of the antifreezing agent left unused on completion of the spray operation by grasping in advance the total spray amount of the antifreezing agent.

Abstract: Provided is a wear amount detection device that is able to detect that a tire is in a worn state, during running, without a special sensor while suppressing an increase in cost. The device includes: a rotation sensor (2) detecting rotation of a wheel (1) to measure a speed of an automobile; a signal processing (3) extracting rotation speed fluctuations synchronized with rotation, from a rotation signal detected by the rotation sensor, and obtain a rotation speed fluctuation pattern synchronized with rotation, from rotation speed fluctuations over a plurality of rotations; and a wear state determination (4) configured to: obtain, from the obtained pattern, a value of a component induced by a characteristic embodied in a tire (1a) of the wheel (1), the value varying in accordance with a wear state of the tire (1a); estimate a wear state of the tire (1a); and output the state.

Abstract: A tire contact state estimation method includes: an information acquisition step of acquiring information of the tire; a correlation strength calculation step of calculating a first correlation strength between the rotational velocity and the braking and driving force, and also calculating a second correlation strength between the slip angle and the generated lateral force; a change detection step of detecting whether the first correlation strength has increased or decreased by a first threshold or more with respect to a predetermined first reference value, and also detecting whether the second correlation strength has increased or decreased by a second threshold or more with respect to a predetermined second reference value; and an estimation step of estimating at least two of the following: a condition of a road surface in contact with the tire, a tire internal pressure state, and a tire abrasion state.

Abstract: A method capable of estimating a snowy road surface condition during vehicular travel in finer classification. In this method, tire vibrations in the circumferential direction, road surface temperature (T), and tire-generated sound are detected by an acceleration sensor, a road surface thermometer, and a microphone, respectively. Then band values P11, P12 and P13 for a pre-leading-edge region (R1), band values P21, P22 and P23 for a leading-edge region (R2), band values P31, P32 and P33 for a pre-trailing-edge region (R3), band values P41 and P42 for a trailing-edge region (R4), and band values P51, P52 and P53 for a post-trailing-edge region (R5) are calculated from the tire vibration data. A sound pressure level ratio (Q)=(PA/PB), which is the ratio of a band power value (PA) of a low frequency band to a band power value (PB) of a high frequency band, is calculated from data on the tire-generated sound.

Abstract: The condition of a road surface on which a vehicle is traveling is estimated accurately, using a tire having a general variable-pitch tire pattern for detection of a road surface condition. The tire for detection of a road surface condition has rows of blocks, the total number N of the circumferentially disposed blocks being 10 or more and the number n of lug grooves, each provided with a joining section connecting circumferentially adjacent blocks, being in the range of (N/2)?n?(N?5). The vibrations of the tire are detected by an acceleration sensor and are subjected to a rotational order ratio analysis by a rotational order ratio analyzing unit. And the road surface condition is estimated by comparing the amplitude P of the rotational order component of the tire vibrations extracted by a rotational order component extracting unit with a predetermined threshold value K.

Abstract: The invention provides a method and apparatus capable of accurately estimating a road surface condition under a traveling vehicle using unsprung acceleration and wheel speed data. The unsprung fore-aft acceleration (Gx) is detected by an acceleration sensor (11) attached to a knuckle (31) which is an unsprung component of a vehicle. At the same time, the wheel speed (Vw) is detected and the variation (?Vw) in wheel speed is calculated. Then the fluctuation range (?(?Vw)) of the variation in wheel speed and the fluctuation range (?(Gx)) of the unsprung fore-aft acceleration are calculated. And whether the road surface is a rough road surface with some bumpiness or a flat (smooth) road surface is estimated from a relationship between the fluctuation range (?(?Vw)) of the variation in wheel speed and the fluctuation range (?(Gx)) of the unsprung fore-aft acceleration.

Abstract: A simple method and apparatus for accurately estimating the contact patch shape of a moving tire. The vibration waveforms of a tire (20) with sipe rows (25A, 25B) formed at the respective pitches (Pa, Pb) in the left and right shoulder lands (24a, 24b) are detected by an acceleration sensor attached to a knuckle of the vehicle. Rotational order spectrums are obtained by performing a rotational order analysis on the vibration waveforms. The peak height (Za) of the rotational order (na) corresponding to the pitch (Pa) and the peak height (Zb) of the rotational order (nb) corresponding to the pitch (Pb) are extracted from the rotational order spectrums.

Abstract: The invention provides a method and apparatus capable of accurately estimating a road surface condition under a traveling vehicle using unsprung acceleration and wheel speed data. The unsprung fore-aft acceleration (Gx) is detected by an acceleration sensor (11) attached to a knuckle (31) which is an unsprung component of a vehicle. At the same time, the wheel speed (Vw) is detected and the variation (?Vw) in wheel speed is calculated. Then the fluctuation range (?(?Vw)) of the variation in wheel speed and the fluctuation range (?(Gx)) of the unsprung fore-aft acceleration are calculated. And whether the road surface is a rough road surface with some bumpiness or a flat (smooth) road surface is estimated from a relationship between the fluctuation range (?(?Vw)) of the variation in wheel speed and the fluctuation range (?(Gx)) of the unsprung fore-aft acceleration.

Abstract: There is provided a method for determining a road surface state which can accurately estimate the road surface state on which a vehicle is running at one of finely classified road surface states based on a sound detection signal from a ground contact surface sound detection unit for detecting a sound in the vicinity of the ground contact surface of the tire of the running vehicle. The method calculates a wave profile of frequency dispersion by executing a 1/N octave analysis of a detected sound signal from a sound detection unit 20 for estimating a road surface state. The state of the road surface on which the vehicle is running is determined whether the calculated wave profile of frequency dispersion satisfies predetermined determination conditions of the respective road surface states. A microphone housed in a container is used to detect said sound, and the determining step is adapted to apply the determination conditions to the measured wave profile including a resonance caused by the container.

Abstract: A vehicle velocity detector 15 is provided, velocity V is detected from position data of the vehicle calculated by using signal from satellites, which is received by a GPS receiver 11 installed to a vehicle body, wheel rotation velocity Vw0 detected by a wheel velocity sensor 12 is corrected in accordance with tire inner pressure detected by a pressure sensor 13 so as to obtain wheel rotation velocity (correction value) Vw, velocity ratio R=(Vw/V), which is ratio of the corrected wheel rotation velocity Vw and the detected wheel velocity V, is calculated and tire wear amount is estimated in accordance with velocity ratio R so that tire wear amount can be measured precisely without processing the tire tread portion.

Abstract: A method capable of estimating a snowy road surface condition during vehicular travel in finer classification. In this method, tire vibrations in the circumferential direction, road surface temperature (T), and tire-generated sound are detected by an acceleration sensor, a road surface thermometer, and a microphone, respectively. Then band values P11, P12 and P13 for a pre-leading-edge region (R1), band values P21, P22 and P23 for a leading-edge region (R2), band values P31, P32 and P33 for a pre-trailing-edge region (R3), band values P41 and P42 for a trailing-edge region (R4), and band values P51, P52 and P53 for a post-trailing-edge region (R5) are calculated from the tire vibration data. A sound pressure level ratio (Q)=(PA/PB), which is the ratio of a band power value (PA) of a low frequency band to a band power value (PB) of a high frequency band, is calculated from data on the tire-generated sound.

Abstract: The condition of a road surface on which a vehicle is traveling is estimated accurately, using a tire having a general variable-pitch tire pattern for detection of a road surface condition. The tire for detection of a road surface condition has rows of blocks, the total number N of the circumferentially disposed blocks being 10 or more and the number n of lug grooves, each provided with a joining section connecting circumferentially adjacent blocks, being in the range of (N/2)?n?(N?5). The vibrations of the tire are detected by an acceleration sensor and are subjected to a rotational order ratio analysis by a rotational order ratio analyzing unit. And the road surface condition is estimated by comparing the amplitude P of the rotational order component of the tire vibrations extracted by a rotational order component extracting unit with a predetermined threshold value K.

Abstract: A simple method and apparatus for accurately estimating the contact patch shape of a moving tire. The vibration waveforms of a tire (20) with sipe rows (25A, 25B) formed at the respective pitches (Pa, Pb) in the left and right shoulder lands (24a, 24b) are detected by an acceleration sensor attached to a knuckle of the vehicle. Rotational order spectrums are obtained by performing a rotational order analysis on the vibration waveforms. The peak height (Za) of the rotational order (na) corresponding to the pitch (Pa) and the peak height (Zb) of the rotational order (nb) corresponding to the pitch (Pb) are extracted from the rotational order spectrums.

Abstract: Provided is a tire contact state estimating method using a tire for estimating a contact state having a block row, in which a plurality of blocks having different lengths in a tire circumference direction are arrayed, and having a tread pattern, in which the kicking ends of two adjacent blocks of the block row are formed at a constant period. The method detects the periodic vibrations, which are generated when the kicking ends to be propagated from the tire to the knuckle leave the road surface sequentially, by an acceleration sensor attached to a knuckle. The method detects such a vibration level of the frequency waveform in a detection frequency band as is calculated from both a wheel speed and that period, to estimate the grounding state of the tire. Thus, without attaching any sensor to the tire, the grounding state of the running tire can be precisely estimated.

Abstract: A pneumatic tires (20FL, 20FR, 20RL, 20RR) each having a plurality of air chambers disposed therein along a tread width direction. An internal pressure control device (100) includes a sensor unit (120) configured to inform a controller (110) that the four-wheel automobile (10) is going as being displaced in the leftward or rightward direction; and the controller (110) configure to change the internal pressures of the plurality of air chambers on the basis of the instruction outputted from the sensor unit (120).

Abstract: here is provided a method for determining a road surface state which can accurately estimate the road surface state on which a vehicle is running at one of finely classified road surface states based on a sound detection signal from a ground contact surface sound detection unit for detecting a sound in the vicinity of the ground contact surface of the tire of the running vehicle. The method calculates a wave profile of frequency dispersion by executing a 1/N octave analysis of a detected sound signal from a sound detection unit 20 for estimating a road surface state. The state of the road surface on which the vehicle is running is determined whether the calculated wave profile of frequency dispersion satisfies predetermined determination conditions of the respective road surface states. A microphone housed in a container is used to detect said sound, and the determining step is adapted to apply the determination conditions to the measured wave profile including a resonance caused by the container.

Abstract: A pneumatic tires (20FL, 20FR, 20RL, 20RR) each having a plurality of air chambers disposed therein along a tread width direction. An internal pressure control device (100) includes a sensor unit (120) configured to inform a controller (110) that the four-wheel automobile (10) is going as being displaced in the leftward or rightward direction; and the controller (110) configure to change the internal pressures of the plurality of air chambers on the basis of the instruction outputted from the sensor unit (120).

Abstract: Provided is a tire contact state estimating method using a tire for estimating a contact state (20) having a block row, in which a plurality of blocks having different lengths in a tire circumference direction are arrayed in the tire circumference direction, and having a tread pattern, in which the kicking ends of two adjacent blocks of the block row are formed at a constant period. The method detects the periodic vibrations, which are generated when the kicking ends to be propagated from the tire (20) to the knuckle (23) leave the road surface sequentially, by an acceleration sensor (11) attached to a knuckle (23), thereby to determine the frequency waveform of the vibrations. The method detects such a vibration level of the frequency waveform in a detection frequency band as is calculated from both a wheel speed (V) measured by a wheel speed sensor (12) and that period, thereby to estimate the grounding state of the tire from the magnitude of that vibration level.

Abstract: A vehicle velocity detector 15 is provided, velocity V is detected from position data of the vehicle calculated by using signal from satellites, which is received by a GPS receiver 11 installed to a vehicle body, wheel rotation velocity Vw0 detected by a wheel velocity sensor 12 is corrected in accordance with tire inner pressure detected by a pressure sensor 13 so as to obtain wheel rotation velocity (correction value) Vw, velocity ratio R=(Vw/V), which is ratio of the corrected wheel rotation velocity Vw and the detected wheel velocity V, is calculated and tire wear amount is estimated in accordance with velocity ratio R so that tire wear amount can be measured precisely without processing the tire tread portion.

Abstract: The dynamic state amount of a tire when a load is applied to the tire while running can be estimated accurately and stably by installing tire deformation amount measuring means 11A and 11B at axisymmetrical positions which are equally distant in the axial direction from the center in the axial direction of the tire on the cross-section in the radial direction of the tire on the inner side of the belt portion of a tire tread in the radial direction, such as at the inner surface of the tread, between an inner liner and a ply, between plies or between a ply and a belt to measure the waveforms of deformation of the tire, detecting the contact time which is the time difference between contact edges from the waveforms of deformation, calculating contact length indices kA and kB from the contact time and the wheel speed detected by a wheel speed sensor 15, calculating the average value k of the above indices kA and kB, and obtaining a load applied to the tire by using the calculated average value k of the indices of