Tire sensor for a tire monitoring system
An assembly determines operating parameters of a tire. The assembly includes a tripod sensor mounted within an inner cavity of the tire underneath a crown portion and an innerliner on which the tripod sensor is mounted. The tripod sensor includes a tri-axial accelerometer for creating a circumferential signal for determining slip ratio, a lateral signal for determining a slip angle, and a radial signal for determining load on the tire.
1. A tire wear state estimation system comprising:
at least one tire supporting a vehicle;
a tri-axial sensor mounted to the tire, the tri-axial sensor measuring tire inflation pressure and generating tire inflation pressure data, measuring tire vertical mode frequency and generating tire vertical mode frequency data, generating tire-specific frequency mode coefficients using tire-specific identification data, and calculating an estimation of a tire wear state based upon the tire inflation pressure data, the vertical mode frequency data, and the tire-specific frequency mode coefficients.
2. The tire wear state estimation system of claim 1 wherein the tri-axial sensor comprises a tire-mounted pressure measuring device operative to measure a tire cavity pressure and transmit the tire inflation pressure data derived from the tire cavity pressure measurement.
3. The tire wear state estimation system of claim 2 wherein the tri-axial sensor comprises tire-specific identification data stored therein.
4. The tire wear state estimation system of claim 3 wherein tire-specific frequency mode coefficients are generated by the tri-axial sensor using on-vehicle or in-tire measurement of a tire vertical mode frequency.
5. The tire wear state estimation system of claim 4 wherein measurement of tire vertical mode frequency performed by a wheel-mounted accelerometer or a tire crown-mounted accelerometer.
6. A tire wear state estimation system comprising:
at least one tire supporting a vehicle;
a tri-axial sensor affixed to the tire operative to measure a tire cavity pressure and transmit tire inflation pressure data; and
tire-specific identification data stored within, and accessible from, the tri-axial sensor, the tri-axial sensor measuring tire vertical mode frequency and generating tire vertical mode frequency data, generating tire-specific frequency mode coefficients using the tire-specific identification data and on-vehicle or in-tire measurement of a tire vertical mode frequency, and calculating an estimation of a tire wear state based upon tire inflation pressure data, tire vertical mode frequency data, and tire-specific frequency mode coefficients.
7. The tire wear state estimation system of claim 6 wherein measurement of the tire vertical mode frequency is from a wheel-mounted accelerometer or a tire crown-mounted accelerometer.
8. A method of tire wear state estimation comprising:
affixing a tri-axial sensor to a vehicle-supporting tire, the tri-axial sensor measuring a tire cavity inflation pressure and generating tire inflation pressure data;
measuring tire vertical mode frequency and generating tire vertical mode frequency data;
generating tire-specific frequency mode coefficients using tire-specific identification data; and
calculating an estimation of a tire wear state based upon the tire inflation pressure data, vertical mode frequency data, and tire-specific frequency mode coefficients.
9. The method of claim 8 further comprising generating tire-specific frequency mode coefficients using on-vehicle or in-tire measurement of a tire vertical mode frequency.
10. The method of claim 9 further comprising measuring the tire vertical mode frequency from a wheel-mounted accelerometer or a tire crown-mounted accelerometer.
11. The method of claim 8 further comprising calculating an estimation of the tire wear state includes employing a correlation model between tire wear state and tire vertical mode frequency.
12. The method of claim 11 further comprising configuring the correlation model to comprise a recursive least squares algorithm based on a polynomial model capturing a dependency between tire wear state, tire inflation pressure data, and tire vertical mode frequency.