METHOD FOR CALIBRATING WIM-SENSORS

• US 20130024152A1
• Filed: 03/24/2011
• Published: 01/24/2013
• Est. Priority Date: 04/01/2010
• Status: Active Grant

• Current Assignee: Kistler Holding AG
• Original Assignee: Kistler Holding AG
• Inventors: Calderara, Reto, Hofmann, Adrian, Cornu, David
• Granted Patent: US 9,851,241 B2
• Time in Patent Office: Days
• US Class Current: 702/101
• CPC Class Codes: G01G 19/022 for weighing wheeled or rolling bodies in motion G01G19/045 takes precedence
• CPC Class Codes: G01G 23/01 Testing or calibrating of weighing apparatus

Abstract

A method for calibrating a WIM (Weigh in Motion) sensor built into a road during travel of a calibrating vehicle measures the dynamic wheel force on the road and on the WIM sensor directly at the measuring wheel, depending on time or location. These wheel force data are transmitted to an evaluating unit. As the calibrating vehicle passes over, WIM signal data are simultaneously measured at the WIM sensor and transmitted to the evaluating unit. The wheel force data are synchronised with the WIM signal data in the evaluating unit. A calibration function is determined by comparing the dynamic wheel force data with the WIM signal data.

Claims

1. A method for calibrating a WIM (Weigh in Motion) sensor built into a road, the sensor being suitable for determining the dynamic and/or static weight of a vehicle as it is passing over the WIM-sensor, wherein the WIM sensor is passed over by a calibrating vehicle which is equipped with at least one measuring wheel, a rotating wheel force dynamometer which rotates with the hub, wherein the dynamic wheel force on the road and on the WIM sensor is measured during travel directly at the measuring wheel, depending on time or location, and these measured wheel force data are transmitted to an evaluating unit, that, in addition, as the calibrating vehicle passes over, WIM signal data are measured at the WIM sensor and transmitted to the evaluating unit, and that the wheel force data are synchronised with the WIM signal data and, on the basis of the comparison of the wheel force data with the WIM signal data, a calibration function is determined and used for the calibration of the WIM sensor.

2. The method according to claim 1, wherein static wheel force R is also ascertained from measuring wheel on a road and is included in the determination of the calibration function.

3. The method according to claim 1, wherein the synchronisation is carried out by means of a received GPS-time and/or GPS-position.

4. The method according to claim 1, wherein the wheel force data and/or the WIM signal data are transmitted contactless to the evaluating unit.

5. The method according to any one of the preceding claim claim 1, wherein additional data concerning the road condition are ascertained on the calibrating vehicle in the area before the passage over the WIM sensor.

6. The method according to claim 1, wherein additional data are ascertained with the measuring wheel or with at least one additional sensor fitted to the calibrating vehicle, in particular the at least one additional sensor being chosen from the following sensors:

distance measuring devices, acceleration sensors and/or spring travel measurement sensors.