Patent attributes
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.