Method and system for reducing errors in vehicle weighing systems

• US 20090125273A1
• Filed: 02/26/2008
• Published: 05/14/2009
• Est. Priority Date: 11/14/2007
• Status: Active Grant

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Abercrombie, Robert K., Hively, Lee M.
• Granted Patent: US 7,783,450 B2
• Time in Patent Office: Days
• US Class Current: 702/175
• CPC Class Codes: G01G 19/035 using electrical weight-sensitive devices
• CPC Class Codes: G01G 23/06 Means for damping oscillations, e.g. of weigh beams
• CPC Class Codes: G01G 23/3735 using a digital network

Abstract

A method and system (10, 23) for determining vehicle weight to a precision of <0.1%, uses a plurality of weight sensing elements (23), a computer (10) for reading in weighing data for a vehicle (25) and produces a dataset representing the total weight of a vehicle via programming (40-53) that is executable by the computer (10) for (a) providing a plurality of mode parameters that characterize each oscillatory mode in the data due to movement of the vehicle during weighing, (b) by determining the oscillatory mode at which there is a minimum error in the weighing data; (c) processing the weighing data to remove that dynamical oscillation from the weighing data; and (d) repeating steps (a)-(c) until the error in the set of weighing data is <0.1% in the vehicle weight.

Claims

1. A method of weighing a vehicle on a plurality of weight-sensing elements and determining vehicle weight with no greater than 0.1% error, the method comprising:

receiving at least one set of weighing data for a vehicle that has passed over respective weight-sensing elements;

processing the weighing data to provide a plurality of mode parameters representing dynamic modes in the weighing data;

analyzing a plurality of mode parameters for the weighing data to minimize the error in the weighing data; and

processing the weighing data to remove data representing the dynamic modes to reduce the error in the sets of weighing data until the error is 0.1% or less in the vehicle weight; and

providing an output of a resultant error for observation by a human observer.

2. The method of claim 1, wherein the analyzing of the mode parameter includes determining a a minimum-error mode at which there is a minimum of error in the weighing data;

and

wherein the processing of weighing data to remove dynamic modes includes removing higher frequency modes and lower frequency modes related to the minimum-error mode.

3. The method of claim 1, after determining the minimum error frequency, further comprising processing the weighing data to remove outlier items of data that are more than two standard deviations from an average weight value from the dataset being processed.

4. The method of claim 1, further comprising synchronizing the weighing data from the front wheels to the weighing data for the rear wheels so as produce a set of weighing data for a weight of an entire vehicle.

5. The method of claim 1, wherein the dataset of weighing data is for a total weight of the vehicle and has been derived from weighing data for the front two wheels, the next two wheels of all successive axles and the rear two wheels of the vehicle.

6. The method of claim 1, wherein the vehicle is traveling at a speed of not more than 5 miles per hour over the weight sensing elements.

7. The method of claim 1, wherein the processing of the weighing data to obtain a plurality of mode parameters further comprises applying a finite Fourier transform calculation to the weighing data.

8. The method of claim 1, wherein each weight sensing element utilizes a plurality of load cells to sense the weight of one wheel portion of a vehicle passing over the weight sensing element.

9. The method of claim 1, wherein the output of a resultant error is in the form of a display on a computer screen.

10. The method of claim 1, wherein the weight sensing elements are part of a vehicle inspection station for also determining a volume of the vehicle.

11. A system determining vehicle weight to a precision of no greater than 0.1% error, the system comprising:

a computer input device for reading in weighing data for a vehicle, as the vehicle passes over a plurality of weight-sensing elements;

means for processing the weighing data from individual weight sensing elements into a dataset representing the total weight of a vehicle;

a first computer program portion executable by a computer for processing the dataset of weighing data to provide a plurality of mode parameters representing oscillatory modes in the data due to dynamic movement of the vehicle during weighing;

a second computer program portion executable by the computer for analyzing a plurality of mode parameters for weighing data to minimize the error in the weighing data; and

a third computer program portion executable by the computer for processing the weighing data to remove the dynamic modes related to movement of the vehicle during weighing and calculating the error in the sets of weighing data until the error is 0.1% or less of the vehicle weight; and

a fourth computer program portion executable by the computer for providing an output of a resultant error for observation by a human observer.

12. The system of claim 11, wherein the error is minimized by determining a minimum error at which there is a minimum of error in the weighing data;

and

wherein the processing of weighing data to remove dynamic modes includes removing higher frequency and lower frequency modes related to the minimum-error mode.

13. The system of claim 12, further comprising a computer program portion for processing the weighing data to remove outlier items of data that are more than two standard deviations from an average weight value from the dataset being processed.

14. The system of claim 11, wherein the means for processing data from individual weight sensing elements into data representing the total weight of a vehicle program includes means for synchronizing the weighing data from the front wheels to the weighing data for the rear wheels so as represent a sample weight of an entire vehicle.

15. The system of claim 11, wherein the dataset of weighing data is for a total weight of the vehicle and has been derived from weighing data for a front two wheels and a rear two wheels of the vehicle.

16. The system of claim 11, wherein the vehicle is traveling at a speed of not more than 5 miles per hour over the weight sensing elements.

17. The system of claim 11, wherein the processing of the weight data to obtain a plurality of mode parameters further comprises applying a finite Fourier transform calculation to the weighing data.

18. The system of claim 11, wherein the output of a resultant error is in the form of a display on a computer screen.

19. The system of claim 11, further comprising a plurality of weight sensing elements for generating weighing data.

20. The system of claim 19, wherein the weight sensing elements each include a plurality of load-sensing devices within each weight sensing element.

21. The system of claim 19, wherein each weight sensing element utilizes a plurality of load cells to sense the weight of one wheel portion of a vehicle passing over the weight sensing element.

22. The system of claim 19, wherein the weight sensing elements are part of a weighing platform for weighing a vehicle.

23. The system of claim 11, wherein the system is part of a vehicle inspection station for determining a volume of the vehicle.