US 2022/0026262 A1 · Calibration of a WIM Sensor

Abstract

A method to calibrate a Weigh in Motion (WIM) sensor that is arranged in a road flush with a road surface for determining a force exerted on the road surface by a vehicle's wheel transgressing the WIM sensor uses an evaluation unit that calculates the wheel force upon receiving the vehicle's velocity and a distance signal from a first device fixed on the vehicle and coordinates the wheel force with a synchronized signal from the WIM sensor to generate a calibrate function for the WIM sensor. The evaluation unit continuously adjusts the wheel force to take into account one or more of wheel pressure, wheel temperature, wheel tilt and vehicle acceleration. A system employing the method includes the vehicle, the evaluation unit, the first device, a synchronization device such as a GPS unit, and sensors for one or more of pressure, temperature, tilt and acceleration.

Claims20

Dependent claims

Method to calibrate a WIM (Weigh in Motion) sensor;

which WIM sensor is arranged in a road flush with a road surface;
which WIM sensor determines a force exerted on the road surface of the road;
wherein the following steps are performed:
a) a device is arranged at a position of a vehicle wherein the position having a distance to the road surface;
the device being configured to measure the distance to the road surface continuously;
the device providing a distance signal to an evaluation unit;
b) a wheel of the vehicle passes over the WIM sensor, the wheel exerting a force on the road surface and the WIM sensor;
the vehicle being equipped with at least one sensor arranged at the vehicle;
said at least one sensor is configured to measure the velocity of the vehicle as a velocity signal and providing a velocity signal to the evaluation unit;
c) the evaluation unit uses the velocity signal and the distance signal to calculate a wheel force exerted on the road surface continuously and provides the calculated wheel force as a calculated wheel force signal;
d) the WIM sensor provides a WIM signal to the evaluation unit as the vehicle passes over the WIM sensor;
e) the evaluation unit uses the calculated wheel force signal and the WIM signal to determine a calibration function;
and
f) the calibration function is used for the calibration of the WIM sensor.

11 more elements

System for calibrating a Weigh-In-Motion (WIM) sensor that is arranged in a road flush with a road surface and configured for determining a force exerted on the road surface by a vehicle's wheel transgressing the WIM sensor, the system comprising:

a vehicle;
an evaluation unit configured for determining a calibration function for the WIM sensor;
and
a first device arranged at a fixed position of the vehicle and being configured to measure continuously the distance between the first device and the road surface and accordingly generate a continuous stream of distance signals, wherein the first device is configured to measure the distance between the first device and the road surface using a contactless technique, and wherein the first device is configured to transmit the continuous stream of distance signals to the evaluation unit.

1 more element

a) arranging at a first fixed position of the vehicle, a first device configured to measure continuously the distance between the first device and the road surface and accordingly provide a distance signal to an evaluation unit;
b) providing to the evaluation unit a velocity signal generated by a velocity sensor that has been disposed at a second fixed position of the vehicle, wherein the velocity sensor is configured to measure the velocity of the vehicle as the vehicle's wheel is transgressing over the WIM sensor and the vehicle's wheel is exerting a force on the road surface and the WIM sensor;
c) using the evaluation unit to calculate continuously from the velocity signal and the distance signal a wheel force exerted on the road surface and accordingly generate a calculated wheel force signal;
d) as the vehicle's wheel passes over the WIM sensor, generating from the WIM sensor a WIM signal that is provided to the evaluation unit;
e) using the evaluation unit to determine a calibration function from the correspondence between the calculated wheel force signal and the WIM signal;
and
f) using the calibration function for the calibration of the WIM sensor.

4 more elements

Dependencies are inferred from the claim text.

Calibration of a WIM Sensor

Life of this patent

Calibration of a WIM Sensor

Life of this patent

Abstract

Claims20