Abstract:
An oscillating structure is coupled to a crown portion of a tyre. The oscillating structure includes a housing and a piezoelectric element coupled to the housing. The piezoelectric element is able to oscillate in an oscillation direction, which could match either a longitudinal or a radial direction of the tyre. An electrical signal generated by the piezoelectric element is processed so as to determine at least one operating parameter of the tyre. The processing includes determining whether a rotation speed of the tyre is greater than a threshold speed; and, in the negative, extracting information for determining the at least one operating parameter of the tyre from a low-pass filtered signal. Such low-pass filtered signal is obtained by removing at least frequency components of the electrical signal having a frequency higher than or equal to a resonance peak frequency of the oscillating structure.
Abstract:
A method and a system for determining a cornering angle of a tyre fitted on a vehicle during running of the vehicle on a rolling surface. The tyre has an equatorial plane. In the method, the length of the contact region between the tyre and the rolling surface is estimated, the length being measured at a distance from the equatorial plane; the load exerted on the tyre is estimated; a camber angle to which the tyre is subjected, is estimated; and the cornering angle is derived from the camber angle, tyre load and contact region length.
Abstract:
A tire has a piezoelectric flexing element associated with an energy storage device (e.g., a capacitor). The piezoelectric flexure element is mounted in cantilever fashion in a housing so as to be positioned substantially along a plane orthogonal to a radial direction of the tire and, so that a first end of the piezoelement is restrained by the housing. A loading mass is coupled to the second end of the piezoelectric flexure element. A small gap is formed between the inner walls of the housing and the outer surface of the loading mass in order to allow limited flexure of the piezo-electric element. The housing including the piezoelectric is mounted in a tire portion in correspondence of a tread area of the tire, preferably on the inner surface of the tire. The piezoelectric element flexes under the action of the radial acceleration when the tire rotates. The loading mass and the gap are chosen to obtain a) small entity oscillations of the flexure element substantially during a complete revolution of the tire when the tire rotates at low speed; b) large entity oscillations of the flexure element substantially only during the passage of the tire portion including the piezoelectric element in the contact patch. Sufficient electrical power for powering an electronic device included within the tire is obtained, together with a long durability of the piezoelectric element.
Abstract:
A system for sensing at least one characteristic parameter of a tire fitted to a vehicle includes a movable unit and a fixed unit. The movable unit is combined with the tire and includes a device for sensing the at least one characteristic parameter, a device for transmitting signals out of the tire, a processing unit, and a storage device. The fixed unit is combinable with the vehicle and includes a device for receiving signals from the movable unit. The processing unit and storage device carry out pre-processing of a signal generated by the sensing device and send the pre-processed signal to the transmitting device. The movable unit may also include a device for generating electrical energy that is capable of supplying the processing unit and the transmitting device. The transmitted signal relates to the at least one characteristic parameter. The movable unit and a vehicle wheel are also disclosed.
Abstract:
A tyre includes an inner surface, at least one monitoring device adhered to the inner surface, and a damping element interposed between the inner surface and the at least one monitoring device. The damping element includes at least one layer of resilient material. The resilient material has a Shore A hardness (measured at 23° C. according to ASTM Standard D2240) greater than or equal to 1 and less than or equal to 40, and an elastic rebound (measured at 23° C. according to ASTM Standard D1054) less than 60. A method for installing the at least one monitoring device includes selecting a portion of the inner surface where the at least one device is to be installed and adhering the at least one device to the selected portion. A kit for installing the at least one monitoring device includes the at least one monitoring device and the damping element.
Abstract:
A system for sensing at least one characteristic parameter of a tyre fitted to a vehicle includes a movable unit and a fixed unit. The movable unit is combined with the tyre and includes a device for sensing the at least one characteristic parameter, a device for transmitting a signal out of the tyre that relates to the at least one characteristic parameter, and a device for generating electrical energy. The fixed unit is combined with the vehicle and includes a device for receiving signals from the movable unit. The electrical energy generating device is capable of supplying electrical energy to the sensing device and to the transmitting device. The electrical energy generating device includes a capacitor that charges itself with electrical energy in response to mechanical stresses applied to the tyre. The movable unit and a vehicle wheel are also disclosed.
Abstract:
A device for generating energy in a rolling wheel includes one part that can move with respect to a wheel rim. The one part is engaged with elastic portion that keeps it in contact with a predetermined bead portion of a tire. The one part undergoes reciprocating outward and return motion against action of the elastic portion, as a result of forces induced in the one part by contact pressure that varies cyclically during each tire revolution and is exerted on the one part by the predetermined bead portion. Also disclosed is a method for generating energy in a rolling wheel that includes subjecting one part of the wheel to elastic force that keeps the one part in contact with the predetermined bead portion, and subjecting the one part to the cyclically-varying contact pressure.
Abstract:
A method for installing a device in a tyre for measuring at least one characteristic parameter of the tyre includes applying the device to a specified area of an inner surface of the tyre, fitting the tyre on a rim, and rotating the tyre. Applying the device includes interpositioning a fixing element between the device and the inner surface of the tyre. The fixing element includes a crosslinkable elastomeric material capable of adhering in a repositionable way to the inner surface of the tyre. Rotating the tyre adapts a shape of the fixing element to the inner surface of the tyre and causes a crosslinking of the crosslinkable elastomeric material. A kit for installing a device for measuring at least one characteristic parameter of a tyre onto an inner surface of the tyre includes the device and at least one fixing element comprising a crosslinkable elastomeric material.
Abstract:
A system for determining interaction between a tyre and a contact surface during movement of a motor vehicle includes at least one first sensor and processing means. The at least one first sensor includes one or more first elongated piezoelectric elements which extend along at least a first portion of the tyre. The at least one first sensor supplies a first signal to the processing means. The first signal is generated by rotation of the tyre and is generated cyclically with each revolution of the tyre. The processing means detects variations in time intervals between distinctive elements of the first signal. A tyre including the system, a kit for detecting behaviour of a tyre moving with respect to a contact surface, a method for monitoring events correlated with interactions between tyres of a moving vehicle and a contact surface, and related systems, tyres, methods, and vehicles are also disclosed.
Abstract:
A method for monitoring instantaneous behavior of a tire in a rolling condition includes acquiring and storing at least one reference curve representing an acceleration profile of at least one specified point of the tire as a function of its position during at least one portion of a revolution of the tire; continuously acquiring signals of acceleration of the at least one point; deriving from the signals of acceleration at least one cyclic curve of acceleration of the at least one point; comparing the at least one cyclic curve with the at least one reference curve; and emitting a signal depending on the comparison that indicates the instantaneous behavior of the tire. The at least one reference curve represents the acceleration profile in at least two directions, including two or more of a centripetal direction, a tangential direction, and a lateral direction. A related system and tire are also disclosed.