Denso Corporation

So-ken Corporation

Tohoku University

Denso Corpora Tion

Yoichiro Suzuki

Takatoshi Sekizawa

Masashi Mori

Nobuya Watabe

Naohito Takasuka

Kenichiro Sanji

Ryosuke Kanbayashi

Akira Takaoka

Hidenori Osai

Hideyuki Ikemoto

Hiroki Kuwano

A road surface state determination device includes a tire-side device and a vehicle-body-side system. The tire-side device is attached to each of a plurality of tires included in a vehicle. The vehicle-body-side system is included in a body of the vehicle. The tire-side device may output a detection signal corresponding to a magnitude of vibration of the tire. The tire-side device may sense the detection signal and generate road surface data indicative of a road surface state appearing in a waveform of the detection signal. The tire-side device may transmit the road surface data. The vehicle-body-side system may perform bidirectional communication with the tire-side device and receive the road surface data. The vehicle-body-side system may determine the road surface state of a road surface on which the vehicle is traveling based on the road surface data.

Road surface state determination device and tire system including same

A tire wear detection apparatus includes a tire side device and a vehicle body side system. The tire side device includes a vibration detection unit, a vehicle speed estimation unit, a signal processing unit, and a first data communication unit. The vibration detection unit is configured to output a detection signal. The vehicle speed estimation unit is configured to estimate the vehicle speed. The signal processing unit is configured to generate wear data. The vehicle body side system includes a second data communication unit and a controller. The controller has a wear determination unit configured to determine a tire wear state based on the wear data. The signal processing unit is configured to acquire the detection signal within a detection signal acquiring range, and calculate a level value of a vibration level of the acquired detection signal within a predetermined frequency range based on a natural frequency of the tire.

Tire wear detection apparatus

A tire side device includes a vibration detection unit that outputs a detection signal according to a magnitude of vibration of a tire, an air pressure detection unit that detects the tire pressure, a data acquisition unit that calculates a contact length of the tire with a road surface based on the detection signal and acquires a wheel load data that is a data related to the wheel load based on the contact length, and a data transmission unit that transmits a data related to the tire pressure and the wheel load data. A vehicle side device includes a receiving unit that receives data on tire pressure and wheel load data, a threshold setting unit that sets an alarm threshold for tire pressure based on the wheel load data, and an alarm determination unit that determines that the tire pressure has decreased when the tire pressure indicated by the data on the tire pressure decreases below the alarm threshold.

Tire pressure monitoring system including tire side and vehicle side devices

A tire wear detection apparatus for a vehicle includes a tire side apparatus and a vehicle body side system. In response to a wet road surface being detected, from a vibration waveform of a tire indicated by a detection signal according to a magnitude of a vibration of the tire, the tire side apparatus is configured to (i) acquire a peak level value of a vibration level at a stepping time at which an apparatus corresponding position in the tire corresponding to an arranged position of the tire side apparatus starts to contact the road surface, and/or (ii) calculate a level value of the vibration level in a post-kicking range after the apparatus corresponding position kicks to separate from the road surface, so as to generate a wear data indicating a wear state of the tire.

Tire wear detection apparatus having a signal processor in the tire side apparatus including a state detection unit and level acquisition unit and/or level calculaton unit

A tire system is configured to enable a general-purpose communication device to establish data communication with a tire-side device, thereby enabling transmission of data indicating a tire-related condition from the tire-side device to the general-purpose communication device. The general-purpose communication device acquires the tire-related condition, and reports the tire-related condition to the user via a notification unit. Based on the above, it is possible to report the tire-related condition via the general-purpose communication device based on the communication between the general-purpose communication device and the tire-side device.

Tire system

A road surface state determination apparatus includes a plurality of tire-side devices each of which detects vibration applied to corresponding tire and produces road surface data indicative of a road surface state based on data of the vibration, and a vehicle-body-side system that determines the road surface state based on the road surface data.

Road surface state determination apparatus

A road surface condition identification apparatus for identifying a road surface condition is provided. The road surface condition identification apparatus includes a vibration detector unit configured to output a detection signal being an analog signal according to magnitude of vibration of the tire. For identifying the road surface condition, the road surface condition identification apparatus performs A-D conversion of converting the detection signal of the vibration detector unit into a digital signal. Based on data on vehicle speed, the road surface to condition identification apparatus sets a conversion range of the magnitude of the vibration of the tire used in the AD conversion from the detection signal into the digital signal.

Road surface condition identification apparatus

A tire-side device is attached to a tire included in a vehicle and applied to a tire apparatus for estimating a condition of a road surface on which the vehicle travels. The tire-side device includes: a vibration detector outputting a detection signal according to a level of vibration of the tire; a controller having a feature quantity extraction device extracting a feature quantity of the detection signal in one rotation of the tire; and a transmitter transmitting road surface data including the feature quantity extracted by the feature quantity extraction device.

Tire-side device and tire apparatus including the same

A road surface state determination device includes a tire-side device and a vehicle-body-side system. The tire-side device is attached to a back surface of a tread of each of a plurality of tires included in a vehicle. The vehicle-body-side system is included in a body of the vehicle. The tire-side device outputs a detection signal corresponding to a magnitude of vibration applied to the tire. The tire-side device generates road surface data indicative of a road surface state appearing in a waveform of the detection signal. The tire-side device transmits the road surface data. The vehicle-body-side system performs bidirectional communication with the tire-side device and receives the road surface data. The vehicle-body-side system determines the road surface state of a road surface on which the vehicle is traveling based on the road surface data.

Road surface state determination device

A collision detection unit corrects a threshold value to a larger value, which a collision check unit uses to compare an output value of a collision detection unit, in case of a rough road surface than in case of a flat road surface. Thus, it becomes possible to suppress erroneous detection on the rough road surface while detecting a collision sensitively on a flat road surface. The rough road is detected by a vibration detection unit provided in a tire side device.

Collision detecting device

In a road surface condition determining device, when determining a road surface condition, a vibration detection unit, a waveform processing unit and a data transmission unit for implementing a sensing function and a data transmission function are not set continuously to an active state for all tire side device, but at least only one tire side device is set to an active state. Remaining one or more is set to a sleep state. A reduction in power consumption of the tire side devices set to the sleep state can thus be achieved. Further, with regard to the at least one tire side device, since the sensing function and the data transmission function remain in the active state, the road surface condition can be reliably determined based on the road surface data of the tire side device.

Road surface condition determining device, and tire system provided with same

A road surface state determination device includes a tire-side device and a vehicle-body-side system. The tire-side device is attached to each of a plurality of tires included in a vehicle. The vehicle-body-side system is included in a body of the vehicle. The tire-side device may output a detection signal corresponding to a magnitude of vibration applied to the tire. The tire-side device may extract data items of a road surface state indicative of the vibration of the tire during one rotation of the tire from the detection signal. The tire-side device may generate road surface data. The tire-side device may transmit the road surface data. The vehicle-body-side system may receive the road surface data. The vehicle-body-side system may determine the road surface state based on the road surface data.

A power generation device is provided. A weight may vibrate in one direction as an axial direction in response to an external vibration. A beam may be arranged in at least one side with respect to the weight in the axial direction of the weight, and vibrate together with the weight. A piezoelectric element may be mounted on the beam. A guide may include a hollow guiding a movement of the weight in the axial direction. A stopper may be included in the weight. The stopper may restrict an amount of the movement of the weight in the axial direction within a predetermined amount. A stopper wall may stop the movement of the weight in the axial direction by contacting with the stopper.

Power generation device

A tire side device is provided with a vibration detection unit that outputs a detection signal corresponding to the magnitude of tire vibration, a control unit that performs to generate road surface data indicating a road surface condition that appears in the waveform of the detection signal, and a first data communication unit that transmits the road surface data. Furthermore, a vehicle body side system is provided with a second data communication unit that receives the road surface data transmitted from the first data communication unit, and a road surface determination unit that determines the condition of the road surface that the vehicle is traveling on the basis of the road surface data. In addition, sensing is performed by the control unit under different sensing conditions at the tire side device of at least one tire among a plurality of tires and the tire side device of at least one other tire among the plurality of tires, and road surface data generated on the basis of the different sensing conditions is transmitted from the first data communication unit.

Road surface condition determination device performing sensing based on different sensing conditions

A vehicle body side system is provided with a second data communication unit that performs bidirectional communication with a tire side device and receives road surface data and measurement data transmitted from a first data communication unit, a road surface determination unit that determines the road surface condition of a road surface on which a vehicle travels based on the road surface data, a reception strength measurement unit that measures the reception strength of the measurement data, and a transmission angle setting unit that stores the reception strength of the measurement data during one rotation of a tire, sets as a transmission angle, a presence angle when the reception strength of the measurement data during one rotation of the tire is high, and transmits data indicating the transmission angle to the tire side device via the second data communication unit. In addition, a control unit causes the first data communication unit to transmit the road surface data when the presence angle becomes the transmission angle.

Growing community of inventors

Nisshin, Japan

Yoichiro Suzuki