A road surface information collection device includes a first sampling unit that samples acceleration sensor's detection results with a first sampling cycle to obtain first sampling data, a position calculator that calculates an acceleration sensor's rotational position based on changes in first sampling data, a second sampling unit that is activated based on a condition that the acceleration sensor is positioned within a first predetermined range including a back side of a point on the tire in contact with the ground, and that samples detection results of the acceleration sensor with a second sampling cycle shorter than first sampling cycle to obtain second sampling data as the road surface information, a speed calculator that detects a rotation speed of the tire based on changes in the first sampling data, and a first predetermined range determination unit that changes the first predetermined range in accordance with the rotation speed of tire.

A tire with a treads depth measuring device that includes a first electrode and a second electrode that are fixed to internal surface of the tire, and an oscillator that is electrically connected to the electrodes so that capacitance between the electrodes affects frequencies of the oscillator. Changes in frequencies of the oscillator can be used to detect and calculate changes in thickness of the tire and changes in depth of treads in the tire.

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.

A vehicle system includes a head vehicle and a tail vehicle that is towed by the head vehicle. Together the head vehicle and tail vehicle have a control subsystem for controlling among other things braking of the tail vehicle. The control subsystem includes a head unit in the head vehicle and a tail unit in the tail vehicle. The head unit further includes a head Inertial Measurement Unit (“IMU”) for measuring orientation and acceleration of the head vehicle, and the tail unit includes a tail IMU for measuring orientation and acceleration of the tail vehicle. With the IMUs, the control subsystem is able to determine relative pitch and orientation of the head vehicle and tail vehicle to control braking and reduce the risk of jackknifing. The tail unit further has wheel speed sensors and a Tire-Pressure Monitoring System (“TPMS”) for sensing wheel speed.

A control unit of a tire side device has a feature amount extraction part, a feature amount storage part, a change determination part, a vehicle speed estimation part, and an algorithm switching part. The change determination part determines whether or not there is a change in the road surface condition based on a present feature amount and a previous feature amount stored in the feature amount storage part, and transmits a road surface data including the present feature amount when there is a change in the road surface condition. The algorithm switching part switches based on the vehicle speed estimation by the vehicle speed estimation part whether to transmit the road surface data from the transmission unit when the road surface condition is changed, or to transmit the road surface data without determining whether or not the road surface condition is changed by the change determination part.

A detection system for extracting information from a sensor module in a rolling wheel comprises: a sensor module which comprises a sensor adapted for sensing a physical property of the tire when mounted in a tire of the wheel or on an inner surface of a tire of the wheel; an acquisition module adapted for sampling a signal from the sensor module, thus obtaining a sequence of data samples; a correlation module adapted for cross-correlating a signed reference sequence with the sequence of data samples thus obtaining a correlation sequence; an extraction module adapted for identifying at least one perturbation in the correlation sequence, wherein the perturbation is induced when a part of the tire where the sensor is mounted hits the ground thereby forming the tire patch.

A rear wheel regenerative braking control system for vehicle, may include a brake controller; a vehicle controller; a hydraulic controller; and a motor controller, wherein the system and the method may maximize an amount of rear wheel regenerative braking while easily securing braking stability of a vehicle.

An autonomous vehicle has a temperature sensor for sensing an air temperature or a road temperature, a processor communicatively connected to the temperature sensor to receive a signal from the temperature sensor, to process the signal and to generate an estimated instantaneous coefficient of friction between a tire of the vehicle and a snow-covered roadway, and a camera to detect salt and/or sand on the roadway and to apply a salt correction factor and/or a sand correction factor to the coefficient of friction to thereby provide a salt-corrected coefficient of friction or a sand-corrected coefficient of friction.

Methods and systems for adaptively configuring a tire mounted sensor (TMS) with vehicle-provided parameters are disclosed. A vehicle control unit obtains data from vehicle sensors and other sources and transmits configuration parameters to the TMS. The TMS signal processing components are configured according to the configuration parameter to minimize the number of tire rotations needed to generate an accelerometric profile and extract a tire feature. The extracted feature is transmitted back to the vehicle control unit with the aim of minimizing the computational resources and battery consumption of the TMS.

A method for evaluating the firmness of the ground on which is running a vehicle equipped with at least one mounted assembly having a radial stiffness k.sub.radial comprising a tyre casing having a crown, two sidewalls and two beads, equipped with a sensor sensitive to the circumferential curvature and positioned in line with the crown, comprises the following steps: Estimating a value of the curvature ρ.sub.A of the tire casing corresponding to first steady-state conditions of the tire casing in contact with the ground; and Evaluating the relative firmness of the ground with respect to the radial stiffness k.sub.radial of the mounted assembly as being a function of the value of the curvature ρ.sub.A of the tire casing.