System and method for determining post-collision vehicular velocity changes Number:7,197,444 from the United States Patent and Trademark Office (PTO) owispatent A system and method that utilizes information relating to vehicle damage information including damaged vehicle area information, crush depth of the damaged areas information, and vehicle component-by-component damage information to estimate the relative velocities of vehicles involved in a collision. The change in velocity is estimated using a plurality of methods, and a determination is made as to which method provided a result that is likely to be more accurate, based on the damage information, and the types of vehicles involved. The results from each method may also be weighted and combined to provide a multi-method estimate of the closing velocity. The methods include using crash test data from one or more sources, estimating closing velocity based on the principals of conservation of momentum, and estimating closing velocity based on deformation energy resulting from the collision.<H determining, vehicular, System, and, meth, 7197444.html, Patent, pto, 7197444

Title: System and method for determining post-collision vehicular velocity changes

Abstract: A system and method that utilizes information relating to vehicle damage information including damaged vehicle area information, crush depth of the damaged areas information, and vehicle component-by-component damage information to estimate the relative velocities of vehicles involved in a collision. The change in velocity is estimated using a plurality of methods, and a determination is made as to which method provided a result that is likely to be more accurate, based on the damage information, and the types of vehicles involved. The results from each method may also be weighted and combined to provide a multi-method estimate of the closing velocity. The methods include using crash test data from one or more sources, estimating closing velocity based on the principals of conservation of momentum, and estimating closing velocity based on deformation energy resulting from the collision.

Patent Number: 7,197,444 Issued on 03/27/2007 to Bomar, Jr., et al.

Inventors: Bomar, Jr.; John B. (San Antonio, TX), Pancratz; David J. (Helotes, TX), Smith; Darrin A. (San Antonio, TX), Kidd; Scott D. (San Antonio, TX)
Assignee: Injury Sciences LLC (San Antonio, TX)

Appl. No.: 10/996,130

Filed: November 22, 2004

Related U.S. Patent Documents


Application Number	Filing Date	Patent Number	Issue Date
10046846	Jan., 2002	6885981
09243202	Feb., 1999	6381561
09018632	Feb., 1998	6470303

Current U.S. Class: 703/8 ; 702/142; 702/150; 703/2

Current International Class: G05B 17/00 (20060101)

Field of Search: 703/1,2,6,7,8 700/303 705/4 702/33,142,150 345/339,340,349

References Cited [Referenced By]

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4435769	March 1984	Nagano et al.
5128859	July 1992	Carbone et al.
5317503	May 1994	Inoue
5377098	December 1994	Sakai
5432904	July 1995	Wong
5469628	November 1995	Chartrand
5504674	April 1996	Chen et al.
5657233	August 1997	Cherrington et al.
5657460	August 1997	Egan et al.
5839112	November 1998	Schreitmueller et al.
5950169	September 1999	Borghesi et al.
6052631	April 2000	Busch et al.
6246933	June 2001	Bague
6718239	April 2004	Rayner
6735506	May 2004	Breed et al.
2002/0103622	August 2002	Burge
2002/0111725	August 2002	Burge et al.
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Foreign Patent Documents


0 644 501	Sep., 1994	EP
PCT/US99/02307	Mar., 1999	WO
WO 99/40529	Aug., 1999	WO

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Primary Examiner: Frejd; Russell
Attorney, Agent or Firm: Trop, Pruner & Hu, P.C.

Parent Case Text

This application is a continuation of U.S. patent application Ser. No. 10/046,846, now U.S. Pat. No. 6,885,981, which was filed on Jan. 14, 2002, which is a continuation of U.S. patent application Ser. No. 09/243,202, now U.S. Pat. No. 6,381,561B1 filed on Feb. 2, 1999, which is a continuation-in-part of U.S. patent application Ser. No. 09/018,632 now U.S. Pat. No. 6,470,303, which was filed on Feb. 4, 1998, all of which are assigned to the same assignee as the present application, and are incorporated by reference in their entirety.

Claims

What is claimed is:

1. A computer-implemented method for estimating impact severity from a repair estimate for a vehicle involved in a collision, the method comprising: acquiring information regarding at least one damaged component of the vehicle, said information comprising repair/replace estimate information; obtaining benchmark data related to the vehicle based at least in part on the repair/replace estimate information; and estimating the impact severity using the benchmark data and outputting the estimate of impact severity to an end user of the computer.

2. The method of claim 1, further comprising determining whether to use the benchmark data for estimating the impact severity based on where the at least one damaged component is located.

3. The method of claim 1, further comprising comparing characteristics of the vehicle to characteristics of vehicles for which benchmark data is available, and determining whether benchmark data for a particular vehicle is applicable to the vehicle.

4. The method of claim 1, further comprising estimating the impact severity according to a plurality of methods to obtain a plurality of estimates.

5. The method of claim 4, further comprising determining a final estimate based on at least one of the plurality of estimates.

6. The method of claim 1, further comprising determining a distribution of impact severity estimates by varying parameters used to determine the impact severity and estimating statistical error in the distribution of impact severity estimates.

7. The method of claim 6, further comprising varying the parameters according to a stochastic simulation.

8. The method of claim 4, further comprising weighting the plurality of estimates and combining the weighted estimates to determine a final estimate for the impact severity.

9. The method of claim 8, further comprising using a statistical method for weighting the results of each estimation method.

10. A computer program product encoded in computer readable media, the computer program product comprising: first instructions, executable by a processor, for receiving repair/replace estimate information regarding one or more damaged vehicle components for at least one vehicle involved in an accident; second instructions, executable by the processor, for estimating impact severity of the at least one vehicle based at least in part on the repair/replace estimate information; and third instructions, executable by the processor, for outputting the impact severity estimate from a computer executing the computer program product.

11. A computer-implemented method for evaluating impact severity of a vehicle involved in a collision, the method comprising: acquiring information regarding at least one damaged component of the vehicle; assigning a damage rating to the vehicle based at least in part on the acquired information; determining a first measure of impact severity based at least partially on the damage rating; determining another measure of impact severity independently of the damage rating; and determining a final impact severity for the vehicle based on an analysis of the first measure and the another measure, and outputting the final impact severity to a user of the computer.

12. The computer-implemented method of claim 11, wherein the final impact severity is determined as a weighted combination of the first measure and the another measure.

13. The computer-implemented method of claim 12, wherein the weighted combination is based upon a correlation between benchmark data and the vehicle.

14. The computer-implemented method of claim 11, further comprising acquiring the information from a repair estimate for the vehicle.

15. A computer-implemented method, comprising: receiving damage information for a subject vehicle involved in an accident; comparing the damage information to benchmark information to determine compliance with a predetermined rule; and estimating an impact severity of the subject vehicle using the benchmark information if the comparing indicates compliance with the predetermined rule, and outputting the impact severity estimate to a user of the computer.

16. The computer-implemented method of claim 15, further comprising performing the estimating iteratively to obtain a population of the impact severity.

17. The computer-implemented method of claim 15, wherein the damage information comprises a plurality of preselected levels corresponding to severity of component damage.

18. The computer-implemented method of claim 17, wherein the severity of component damage is determined with reference to repair/replace estimate information.

19. The computer-implemented method of claim 15, wherein the predetermined rule comprises whether the benchmark information is greater than the damage information.

20. The computer-implemented method of claim 15, wherein the benchmark information relates to a crash test vehicle comparable with the subject vehicle.

21. The computer-implemented method of claim 15, wherein the benchmark information is derived from at least one of IIHS or CR crash test data.

22. The computer-implemented method of claim 15, further comprising evaluating injury potential for an occupant of the subject vehicle based on the impact severity.

23. The computer-implemented method of claim 15, further comprising comparing the damage information to the benchmark information, wherein the benchmark information comprises a plurality of benchmark ratings.

24. The computer-implemented method of claim 15, further comprising receiving the damage information from a repair estimate for the subject vehicle.

25. A computer-implemented method, comprising: receiving a damage rating for a subject vehicle involved in an accident; comparing the damage rating to a plurality of reference sets to determine compliance with at least one predetermined rule, the reference sets being associated with one or more reference vehicles comparable with the subject vehicle; and estimating an impact severity of the subject vehicle using data from at least one of the reference vehicles if the comparing indicates compliance with the at least one predetermined rule, and outputting the impact severity estimate to a user of the computer.

26. The computer-implemented method of claim 25, wherein the at least one predetermined rule comprises a best fit between the plurality of reference sets and the damage rating.

27. The computer-implemented method of claim 25, further comprising evaluating injury potential for an occupant of the subject vehicle based on the impact severity.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to electronic systems and more particularly relates to a system and method for quantifying vehicular damage information.

2. Description of the Related Art

Vehicular accidents are a common occurrence in many parts of the world and, unfortunately, vehicular accidents, even at low impact and separation velocities, are often accompanied by injury to vehicle occupants. It is often desirable to reconcile actual occupant injury reports to a potential for energy based on vehicular accident information. Trained engineers and accident reconstruction experts evaluate subject vehicles involved in a collision, and based on their training and experience, may be able to arrive at an estimated change in velocity (".DELTA.V") for each the subject vehicles. The potential for injury can be derived from knowledge of the respective .DELTA.V's for the subject vehicles.

However, involving trained engineers and accident reconstruction experts in all collisions, especially in the numerous low velocity collisions, is often not cost effective.

SUMMARY OF THE INVENTION

In one embodiment of the present invention, a computer program product, encoded in computer readable media, includes program instructions, which, when executed by a processor, are operable to receive input information regarding damaged vehicle components for at least one vehicle, categorize damage zones with respect to the location of the bumper of a vehicle, categorize a vehicle component with respect to its location on the vehicle, and estimate the change in the vehicle's velocity as a result of a collision based on the damaged vehicle components information. The information regarding damaged vehicle components includes particular damaged vehicle components, locations of damaged vehicle components, depth information corresponding to the damaged vehicle components, and an overall vehicle damage rating.

In a further embodiment, a computer system executing the computer program product is operable to compare the overall vehicle damage rating to a crash test vehicle damage rating, and to determine whether to use crash test data to estimate the change in the vehicle's velocity, based on the comparison and the location of damaged components. The executing computer program product further compares characteristics of a damaged vehicle to characteristics of vehicles for which crash test data is available, and determines whether crash test data for a particular vehicle is applicable to the damaged vehicle. The executing computer program product then determines a coefficient of restitution to use in estimating the change in the vehicle's velocity.

In a further embodiment, the executing computer program product is operable to estimate the change in the vehicle's velocity based either on the crash data, or the on conservation of momentum. The change in vehicle velocity is later input to a multi-method change in velocity combination generator.

In a further embodiment, the computer program product includes a change in velocity determination module which computationally estimates the change in vehicle velocity based on estimates of deformation energy and principal forces. Deformation energy may be estimated using a one-way spring model. Principal forces may be estimated based on at least one stiffness parameter and the damage depth information. In a further embodiment, the executing computer program product is operable to compare principal forces for at least two vehicles and determine whether the stiffness parameters, the depth information, and/or the principal forces may be adjusted within predetermined thresholds to substantially balance the principal forces.

In a further embodiment, the executing computer program product is operable to estimate closing velocity based on an estimate of a coefficient of restitution. A distribution of changes in velocity may be determined by varying parameters used to estimate the change in velocity. Statistical error functions in the distribution of changes in velocity may also be estimated and used to vary the parameters. In a further embodiment, distribution of changes in velocity are estimated using stochastic simulation.

In a further embodiment, the computer program product includes override/underride logic that is operable to determine stiffness parameters based on the position of the vehicle's bumper relative to the position of another vehicle's bumper.

In a further embodiment, the computer program product includes a multi-method change in velocity generator that is operable to estimate the change in the vehicle's velocity as a result of a collision based on a plurality of estimation methods including estimation based on one set of crash test data, estimation based on another set of crash test data, and estimation based on conservation of momentum. In a further embodiment, the results of each estimation method are weighted and combined to determine a final estimate for the change in the vehicle's velocity. In a further embodiment, the results for each estimation method may be weighted using a statistical method, such at the t-test.

In another embodiment, a computer-implemented method for estimating the change in velocity of a vehicle as a result of a collision, is provided which includes

acquiring information regarding damaged components of at least one vehicle,

assigning a damage rating to the at least one vehicle,

determining whether to utilize crash test data for a first estimate of the change in velocity for the at least one vehicle based at least partially on the damage rating,

determining a second estimate of the change in velocity for the at least one vehicle based on conservation of momentum,

determining a third estimate of the change in velocity for the at least one vehicle based on deformation energy, and

determining a final estimate of the change in velocity for the at least one vehicle based on at least one of the first, second, and third estimates of the change in velocity.

In a further embodiment, the method includes determining whether to utilize crash test data for a first estimate of the change in velocity for the at least one vehicle based on the location of damaged components.

In a further embodiment, the method includes comparing the location of damaged components on vehicles involved in the same collision to determine whether to use crash test data to estimate the change in at least one of the vehicles' velocity.

In a further embodiment, the method includes comparing characteristics of a damaged vehicle to characteristics of vehicles for which crash test data is available, and determining whether crash test data for a particular vehicle is applicable to the damaged vehicle.

In a further embodiment, the method includes estimating principal forces based on at least one stiffness parameter and the depth information.

In a further embodiment, the method includes comparing principal forces for at least two vehicles and determining whether vehicle parameters may be adjusted within predetermined thresholds to substantially balance the principal forces.

In a further embodiment, the method includes determining a distribution of changes in velocity by varying parameters used to estimate the change in velocity and estimating statistical error in the distribution of changes in velocity.

In a further embodiment, the method includes varying parameters according to a stochastic simulation.

In a further embodiment, the method includes determining stiffness parameters based on the position of the vehicle's bumper relative to the position of another vehicle's bumper.

In a further embodiment, the method includes weighting the first, second, and third estimates of the change in velocity and combining the weighted estimates to determine the final estimate for the change in the vehicle's velocity.

In a further embodiment, the method includes using a statistical method for weighting the results of each estimation method.

BRIEF DESCRIPTION OF THE DRAWINGS

Features appearing in multiple figures with the same reference numeral are the same unless otherwise indicated.

FIG. 1 is a computer system.

FIG. 2 is a .DELTA.V determination module for execution on the computer system of FIG. 1.

FIG. 3 is an exemplary vehicle for indicating damage zones.

FIGS. 4A and 4B illustrate a graphical user interface which allows the .DELTA.V crush determination module of FIG. 2 to acquire data on a subject vehicle.

FIGS. 5, 5A, 6, 7A, 7B, and 10 are graphical user interfaces which allow the .DELTA.V crush determination module of FIG. 2 to acquire and display information.

FIG. 8 is a coefficient of restitution versus vehicle weight plot.

FIG. 9 is a coefficient of restitution versus closing velocity plot.

FIG. 10 is an example of a graphical user interface for balancing forces on vehicles involved in a collision.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the invention is intended to be illustrative only and not limiting.

Determining vehicular velocity changes (".DELTA.V") which occur during and after a collision is useful in evaluating the injury potential of occupants situated in the vehicle. Knowledge of the .DELTA.V allows evaluators to, for example, reconcile vehicle occupant injury reports to injury potential and to detect potential reporting inaccuracies.

In most situations, the actual .DELTA.V experienced by a vehicle in a collision ("subject vehicle") is unknown. A .DELTA.V determination module utilizes one or more methodologies to acquire relevant data and estimate the actual .DELTA.V experienced by the subject, accident subject vehicle ("subject vehicle"). The methodologies include estimating a subject vehicle .DELTA.V based upon available and relevant crash test information and subject vehicle damage and include a .DELTA.V crush determination module 216 (FIG. 2) which allows estimation of .DELTA.V from crush energy and computation of barrier equivalent velocities ("BEV") using estimates of residual subject vehicle crush deformation and subject vehicle characteristics. Additionally, conservation of momentum calculations may be used to estimate and confirm a .DELTA.V for one or more subject vehicles in a collision. Furthermore, the various methodologies may be selectively combined to increase the level of confidence in a final estimated .DELTA.V.

Referring to FIG. 1, a computer system 100 includes a processor 102 coupled to system memory 104 via a bus 106. Bus 106 may, for example, include a processor bus, local bus, and an extended bus. A nonvolatile memory 108, which may, for example, be a hard disk, read only memory ("ROM"), floppy magnetic disk, magnetic tape, compact disk ROM, other read/write memory, and/or optical memory, stores machine readable information for execution by processor 102. Generally, the machine readable information is transferred to system memory 104 via bus 106 in preparation for transfer to processor 102 in a well-known manner. Computer system 100 also includes an I/O ("input/output") controller 110 which provides an interface between bus 106 and I/O device(s) 112. In a well-known manner, information received by I/O controller 110 from I/O device(s) 112 is generally placed on bus 106 and in some cases stored in nonvolatile memory 108 and in some cases is utilized directly by processor 102 or an application executing on processor 102 from system memory 104. I/O device(s) 112 may include, for example, a keyboard, a mouse, and a modem. A modem transfers information via electronic data signals between I/O controller 110 and an information source such as another computer (not shown) which is coupled to the modem via, for example, a conductive media or electromagnetic energy.

Computer system 100 also includes a graphics controller 114 which allows computer system 100 to display information, such as a windows based graphical user interface, on display 116 in a well-known manner. It will be understood by persons of ordinary skill in the art that computer system 100 may include other well-known components.

Referring to FIG. 2, a .DELTA.V determination module 200 is generally machine readable information disposed in a machine readable medium which may be executed by processor 102 (FIG. 1). Machine readable media includes nonvolatile memory 108, volatile memory 104, and the electronic data signals used to transfer information to and from I/O device(s) 112, such as a modem. .DELTA.V determination module 200 includes data acquisition module 202 which facilitates receipt of subject vehicle information for determining a subject vehicle .DELTA.V based upon available and relevant crash test information. As described in more detail below, the information may also be utilized to combine determined subject vehicle .DELTA.V's and adjust stiffness factors used to estimate subject vehicle .DELTA.V's in .DELTA.V crush determination module 216.

Component-by-Component Damage Rating Assignment.

To use subject vehicle data acquired in data acquisition module 202, crash test data is assigned a component-by-component rating. Crash test data is available from various resources, such as the Insurance Institute for Highway Safety (IIHS) or Consumer Reports (CR). The crash test data is derived from automobile crash tests performed under controlled circumstances. IIHS crash data is provided in the form of repair estimates and is more quantitative in nature than CR crash test data. The CR crash test results are more qualitative in nature and are frequently given as a verbal description of damage. Thus, the confidence level in the CR crash test result component-by-component rating is slightly lower than that of the IIHS tests.

A uniform component-by-component damage rating assignment has been developed for, for example, IIHS and CR low velocity crash data and for acquired subject vehicle crash data which allows comparison between the crash test information and the subject accident. The component-by-component damage rating assignment is an exemplary process of uniform damage quantification which facilitates .DELTA.V estimations without requiring highly trained accident reconstructionists.

In one embodiment, the component-by-component damage rating assignment rates the level of damage incurred in the IIHS barrier test based on the repair estimate information provided by IIHS. The rating system looks at component damage and the severity of the damage (repair or replace) to develop a damage rating. This damage rating is then compared with a damage rating for the subject accident using the same criteria and the repair estimate from the subject accident. The same rating system was used to rate the CR bumper basher test results based on the verbal description of the damaged components.

In component-by-component damage evaluator 204, subject vehicle damage patterns are identified and rated on a component-by-component basis to relate to crash test rated vehicles as described in more detail below.

Referring to FIG. 3, a side view of a typical subject vehicle 302 includes a front portion 304 and rear portion 306 which can be divided into two zones to describe the damage to the subject vehicle 302. One zone is at the level of the bumper (level "L"), and one zone is between the bumper and the hood/trunk (level "M"). The "M" and "L" zones describe the specific vertical location of subject vehicle damage. Zone L contains bumper level components, and Zone M contains internal and external components directly above the bumper level and on the subject vehicle sides.

In one embodiment, damage to the front and rear bumpers 308 and 310, respectively, are categorized into: damage to the external components of the bumper; damage to the internal components of the bumper; and damage beyond the structures of the bumper. Thus, the damage to the subject vehicle 302 can be divided into two groups,

Groups I and II, for zone "L". A third group, Group III, covers component damage beyond the bumper structure in zone "M".

Group I. External Bumper Components Bumper cover Impact strip Bumper guards Moulding Group II. Internal Bumper Components Energy absorber(s) 1. Isolators 2. Foam 3. Eggcrate 4. Deformable struts Impact bar or face bar Mounting brackets Front/Rear body panel Bumper unit Group III. Outermost External Subject Vehicle Components Safety-related equipment 1. Headlamps/Taillamps 2. Turn lamps 3. Side marker lamps 4. Back up lamps Grille/Headlamp mounting panel Quarter panels/Fenders Hood panel/Rear deck lid Radiator support panel

The component-by-component damage evaluator 204 rates damage components in accordance with the severity of component damage. In one embodiment, numerical ratings of 0 to 3, with 3 depicting the most severe damage, are utilized to uniformly quantify damage. The ratings indicate increasing damage to the subject vehicles in the crash tests. For example, a "0" rating in zone "L" indicates no or very minor damage to the subject vehicle. A rating of "3" in zone L indicates that the subject vehicle's bumper to prevent damage has been exceeded and there is damage beyond the bumper itself. Thus, the results of crash tests can be compared with damage to a subject vehicle entered into computer system 100 via an input/output device(s) 112. For example, if a bumper is struck and only has a scuff on the bumper cover requiring repair, a damage rating of "0" is assigned to level "L" based on this low severity of damage. Similarly, if the radiator of the other subject vehicle is damaged along with other parts, it would be assigned a rating of "3" for zone "L". Although a barrier impact test is not an exact simulation for a bumper-to-bumper impact, the barrier impact test is a reasonable approximation for the bumper-to-bumper impact. Additionally, conservative repair estimates result in overestimating of .DELTA.V, and overestimating .DELTA.V will result in a more conservative estimate for injury potential. Table 1 defines damage ratings for Groups I, II, and III components based on damage listed in repair estimates.

TABLE-US-00001 TABLE 1 Group I Group II Group III Components Components Components No Damage 0 Repair 0 1 3 Replace 1 2 3

The "3" rating indicates structures beyond the bumper have been damaged, and it is generally difficult to factor the level of damage above the bumper into the rating for the bumper. Thus, in one embodiment, to simplify the rating system, a rating of "3" for zone "L" makes the use of the crash tests invalid in the .DELTA.V determination module 200.

A similar damage rating system can be developed for zone "M", the areas beyond the bumper, for the purpose of determining override/underride.

The damage in zone "L" and zone "M" is separately evaluated to evaluate the possibility of bumper override/underride. For example, if the front bumper 308 of subject vehicle 302 is overridden, there would be little or no damage in zone "L" and moderate to extensive damage in zone "M". As with the zone "L" group, the damage in zone "M" can be categorized by the extent of damage. The subject vehicle components in zone "M" for the front of the subject vehicle 302 can also be divided into three groups: Group I. Grille/Safety Equipment Grille Headlamp housing, headlamp lens Turnlamp housing, turnlamp lens Parklamp housing, parklamp lens Group II. External Body Panels Hood panel Fenders Group III. Radiator/Radiator Support/Unibody Radiator support panel Radiator Valence panel Unibody/frame structure

Table 2 below defines a damage rating in zone "M" for the front 304 of the subject vehicle 302.

TABLE-US-00002 TABLE 2 Group I Group II Group III Components Components Components No Damage 0 Repair 0 2 3 Replace 1 3 3

The subject vehicle components in zone "M" for the rear 306 of subject vehicle 302 can also be divided into three groups: Group I. Outermost Subject Vehicle Components Taillamp housing, taillamp lens Turnlamp housing, turnlamp lens Rear body panel Group II. Rear Body Structures Rear deck lid (Tailgate shell--vans, mpv's, wagons) Quarter panels Rear floor pan Group III. Forward Components (Components Ahead of the Rear Bumper 310) Rear wheels Rear roof pillars Rear doors Unibody/frame structures Table 3 defines a damage rating to zone "M" for the rear 306 of the subject vehicle 302.

TABLE-US-00003 TABLE 3 Group I Group II Group III Components Components Components No Damage 0 Repair 1 2 3 Replace 1 3 3

Component-by-component damage ratings are also assigned to a subject vehicle by component-by-component damage evaluator 204. The components of the subject vehicle are divided into zones "L" and "M" as shown in FIG. 3 and a damage rating is assigned in accordance with Tables 1, 2, and 3. In the event that a repair estimate or component replacement data is unavailable, the damage rating for zones "L" and "M" is inferred from visual estimates of the subject vehicle damage. Table 4 shows subject vehicle components which might be damaged in front/rear collisions. A description of the visual damage that is likely to be sustained by these components and the repair estimate inference from the damage is also provided. This information is used to assign single digit damage codes for each of zones "L" and "M". The table columns for the codes assume only the part damaged in the manner described. It does not take into account multi-component damage or the damage hierarchy discussed in Tables 1 3. Visual ratings are preferably not used if a repair estimate is available for the subject vehicle. As with Tables 1 3, the component damage ratings are assigned to indicate increasing levels of component damage. Bumper components have no zone "M" rating. As shown in Table 1, any parts which are damaged in any manner above or beyond the bumper results in a "3" rating for zone "L". This will preclude the use of the crash tests for the subject vehicle 302. A comparison of the level of damage to the bumper and the level of damage above the bumper is still used to evaluate the possibility of override/underride relative to the other subject vehicle in the collision.

TABLE-US-00004 TABLE 4 Repair Vehicle Estimate Component Visual Description Inference "L" Code* "M" Code Bumper rotated, separated from body, replace 2 NA dented, deformed Bumper scratched, smudged, scuffed, repair 0 NA cover/face bar paint transfer Bumper cracked, dented, chipped, cut, replace 1 NA cover/face bar deformed Bumper guard scratched, smudged, scuffed, repair 0 NA paint transfer Bumper guard cracked, dented, chipped, cut, replace 1 NA deformed License plate scratched, smudged, scuffed, repair 0 NA bracket paint transfer License plate cracked, dented, chipped, cut, replace 0 NA bracket deformed Moulding scratched, smudged, scuffed, repair 0 NA paint transfer Moulding cracked, dented, chipped, cut, replace 0 NA deformed Impact strip scratched, smudged, scuffed, repair 0 NA paint transfer Impact strip cracked, dented, chipped, cut, replace 0 NA deformed Bumper step pad scratched, smudged, scuffed, repair 0 NA paint transfer Bumper step pad cracked, dented, chipped, cut, replace 1 NA deformed Energy absorbers stroked, compressed repair 0 NA Energy absorbers deformed, leaking, bottomed replace 1 NA out Grille broken, cracked, chipped replace 3 1 Lamp broken, cracked, chipped replace 3 1 lenses/assemblies Front/rear body scratched, paint transfer repair 3 2 panels Front/rear body dented, deformed replace 3 3 panels Front fender scratched, paint transfer repair 3 2 Front fender dented, deformed replace 3 3 Rear quarter panel scratched, paint transfer repair 3 2 Rear quarter panel dented, deformed replace 3 3 Hood scratched, paint transfer repair 3 2 Hood dented, deformed replace 3 3 Deck lid/tailgate scratched, paint transfer repair 3 2 shell Deck lid/tailgate dented, deformed replace 3 3 shell

Referring to FIG. 4A, the data acquisition module 202 provides a graphical user interfaces 402 and 404 with user interface generator 206 to allow a user to enter subject vehicle damage for use in generating a subject vehicle damage rating based upon component-by-component damage ratings and crash test subject vehicle comparisons. The user interface generator 206 provides graphical user interface 402 with an exemplary list 406 of subject vehicle components for the appropriate end of the subject vehicle 402 which in the embodiment of FIG. 4A is the rear end. Damaged subject vehicle components can be selected from the list 406 to create a list of damaged components. For each damaged component, the graphical user interface 402 allows a user to select whether components were repaired or replaced for subject vehicles with a repair estimate. The data acquisition module 202 then determines the appropriate damage rating for the subject vehicle in the subject accident according to Tables 1 and 2.

Referring to FIG. 4, the graphical user interface 404 allows a user to select and indicate which, if any, components that do not have a repair estimate are visually damaged. Both front and rear (not shown) views of exemplary vehicle images are displayed by graphical user interface 404. The visual damage to the components is characterized via a selection of cosmetic or structural damage in accordance with Table 4. A rating to components with a visual damage estimate only is assigned in accordance with Table 4.

After damage ratings have been assigned on the component-by-component basis, an overall subject vehicle damage rating is assigned in subject vehicle damage rating operation 208 to the two crash test subject vehicles and to the subject vehicle based upon the component-by-component ratings assigned in accordance with Table 1. The subject vehicle damage rating corresponds to the highest rating present in Table 1 for that subject vehicle. For example and referring to Table 1, if any Group III components are replaced or repaired, the subject vehicle is assigned a damage rating of 3. If any Group II components are replaced, the subject vehicle is assigned a damage rating of 2. If any Group II components are repaired or any Group I components are replaced, the subject vehicle is assigned a damage rating of 1. If any Group I components are repaired or no damage is evident, the subject vehicle is assigned a damage rating of 0.

Determination of .DELTA.V Based on Subject Vehicle Damage Ratings

In crash test based .DELTA.V determination operation ("crash test .DELTA.V operation") 210, the subject vehicle damage rating is compared to an identical crash test vehicle damage rating, if available, or otherwise to a sister vehicle crash test vehicle damage rating to determine whether or not crash test based .DELTA.V's should be used. As depicted in Table 1, if a subject vehicle overall damage rating is greater than a respective crash test based sister vehicle overall damage rating, the respective crash test information is not used in estimating a .DELTA.V for the subject vehicle.

TABLE-US-00005 TABLE 5 Subject vehicle Crash TestVehicle Damage Rating Damage Rating 0 1 2 3 0 A X X X 1 A A X X 2 A A A X 3 A A A X

An "A" in Table 5 indicates that the respective crash test based information may be used by crash test .DELTA.V operation 210 to determine a .DELTA.V for the subject vehicle, and an "X" in Table 5 indicates that the subject vehicle received more damage than the IIHS crash test subject vehicles and, thus, the IIHS crash test is not used by crash test .DELTA.V operation 210 to obtain a subject vehicle .DELTA.V. When Group III components in the subject vehicle were damaged, a crash based subject vehicle .DELTA.V is not estimated by .DELTA.V determination module 200.

In one embodiment, crash test .DELTA.V operation 210 uses the IIHS and CR crash test information to develop .DELTA.V estimates. The crash tests preferably considered in crash test .DELTA.V operation 210, the IIHS and CR crash tests, are conducted under controlled and consistent conditions. While the closing velocities i.e. barrier equivalent velocities ("BEV") are known in these tests, the coefficient of restitution is not known. The coefficient of restitution ranges from 0 to 1 and has been shown to vary with the closing velocity. The coefficient of restitution can be estimated using data from vehicle-to-barrier collisions of known restitution. For IIHS tests, the coefficient of restitution versus vehicle weight is plotted in FIG. 8. The coefficient of restitution for test vehicles in the CR crash tests is estimated to have a mean of 0.5 with a standard deviation of 0.1.

The assignment of .DELTA.V based on crash test comparisons is generally based on the assumption that a bumper-to-bumper impact is simulated by a barrier-to-bumper impact. The barrier-to-bumper impact is a flat impact at the bumper surface along the majority of the bumper width. The bumper-to-barrier impact is a reasonable simulation for the accident if the contact between two subject vehicles is between the bumpers of the subject vehicles along a significant portion of the respective bumper widths, for example, more than one-half width overlap or more than two-thirds width overlap. If any subject vehicle receives only bumper component damage, then a crash based test determined .DELTA.V may be performed based on the outcome of vehicle rating comparisons in Table 1. If the impact configuration entered during execution of data acquisition module 202 includes any damage to any components in zone M, a bumper height misalignment may exist, i.e. override/underride situation. In one embodiment, if components in zone M are damaged, a crash test based .DELTA.V estimation will not be directly used for the subject vehicle with damage to any zone M component because the impact force may have exceeded the bumper's ability to protect structures above or beyond the bumper. In another embodiment, if components in zone M receive only minor or insubstantial damage, such as headlight or taillight glass breakage, a crash test based .DELTA.V estimation will be used in multi-method .DELTA.V combination generator 232.

In one embodiment, the assumption of bumper-to-bumper contact is evaluated by crash test .DELTA.V operation 210 by considering the damage patterns exhibited by both subject vehicles. If there is no damage to either subject vehicle or there is evidence of damage to the bumpers of both subject vehicles, then a bumper-to-bumper collision will be inferred by crash test .DELTA.V operation 210. This inference will be confirmed with the user through a graphical user interface displayed inquiry produced by user interface generator 206 since the user may have additional information not necessarily evident from the damage patterns. In the event of a bumper height misalignment, crash test .DELTA.V operation 210 will infer from the damage patterns the override/underride situation. Again, the inference will be confirmed with the user through a graphical user interface displayed inquiry. In the override/underride situation, crash test .DELTA.V operation 210 would determine a .DELTA.V based on crash test information only for the subject vehicle with bumper impact. The subject vehicle having an impact above/below the bumper would fail the bumper-to-bumper collision requirement. If the damage patterns are such that the program cannot infer override/underride, crash test .DELTA.V operation 210 will request the user, through a graphical user interface displayed inquiry, to specify whether override/underride was present and which subject vehicle overrode or underrode the other.

Crash test vehicle information is utilized by crash test .DELTA.V operation 210 to estiimate a subject vehicle .DELTA.V if the crash test vehicle is identical or similar ("sister vehicle") to the subject vehicle. To determine if a crash test vehicle is a identical or a sister vehicle to the subject vehicle, damage on a component by component basis can be determined, and, if components remain the same over a range of years, the crash test information may be extended to crash test results over the range of years for which the bumper and its components have remained the same. Mitchell's Collision Estimating Guide (1997) ("Mitchell") by Mitchell International, 9889 Willow Creek Road, P.O. Box 26260, San Diego, Calif. 92196 and Hollander Interchange ("Hollander") by Automatic Data Processing (ADP) provide repair estimate information on a subject vehicle component level. The parts are listed individually and parts remaining the same over a range of years are noted in Mitchell and Hollander.

In addition, subject vehicles with the same bumper system, same body and approximately the same weight are considered sister subject vehicles as well. For example, a make and model of a subject vehicle have different trim levels but the same type of bumper system. It is reasonable to expect the bumper system on such a subject vehicle to perform in a similar manner as the crash tested subject vehicle if the subject vehicle weights are similar (e.g. within 250 lb.). Likewise, subject vehicles of different models but the same manufacturer (e.g. Pontiac Transport.TM., Chevrolet APV.TM., Chevrolet Lumina.TM., and Oldsmobile Silhouette.TM. vans) or subject vehicles of different makes and models (e.g. Geo Prizm.TM. and Toyota Corolla.TM.) with the same bumper system and body structure as the crash tested subject vehicle should be expected to perform in the same manner. The weight of the identical or sister crash tested vehicle versus the subject vehicle should be taken into consideration when determining whether a damage rating can be assigned because the assumption is that the subject vehicle would experience a similar force on a similar structure since force depends on mass.

Referring to FIG. 8, a plot of the coefficient of restitution, e, versus vehicle weight for IIHS for use in determining subject vehicle .DELTA.V from IIHS crash test information is shown. .DELTA.V is related to the test vehicle coefficient of restitution in accordance with equation [0]: .DELTA.V=(1+e)V [0]

where v is the actual velocity of a test vehicle in the IIHS crash test. The IIHS crash test is conducted by running the test vehicle into a fixed barrier with a v of 5 miles per hour ("mph"), and the IIHS crash test vehicle weight is known or can be approximately determined by identification of the make and model.

A best fit curve for the data points plotted in FIG. 8 is shown as a solid line. Upper and lower bounds for the coefficient of restitution corresponding to a particular vehicle weight are also shown spanning either side of the best fit curve. Crash test .DELTA.V operation 210 determines a population of coefficients of restitution using the best fit curve data point corresponding to a particular subject vehicle weight as a mean and assuming a normal distribution of the coefficients of restitution within the indicated upper and lower bounds. The population of, for example, one thousand coefficients of restitution are applied in equation 0 by crash test .DELTA.V operation 210 to obtain a population of .DELTA.V's for the subject vehicle based on IIHS crash test vehicle information. This IIHS based .DELTA.V population is subsequently utilized by multi-method .DELTA.V combination generator 232.

For CR crash tests, .DELTA.V is related to the test vehicle coefficient of restitution, e, in accordance with equation [00]: .DELTA.V=(1+e)V/2 [00]

The CR crash test is conducted by running a sled of equal mass into a crash test subject vehicle. The crash test subject vehicle is not in motion at the moment of impact, and the CR crash test V is 5 mph for front and rear collision tests and 3 mph for side collision tests. Assuming a mean coefficient of restitution of 0.5 and a standard deviation of 0.1, crash test .DELTA.V operation 210 utilizes a normal distribution of coefficients of restitution for the CR crash test, bounded by the standard deviation, to obtain a population of CR crash test based .DELTA.V's using equation 0. The CR based .DELTA.V population is, for example, also a population of one thousand .DELTA.V's, and is subsequently utilized by multi-method .DELTA.V combination generator 232.

Conservation of Momentum

If both of the subject vehicles in the accident have a crash test, a conservation of momentum calculation is performed in the conservation of momentum operation 212 for each of the subject vehicles based on each of the crash test based .DELTA.V determinations of the other subject vehicle. The conservation of momentum equation is generally defined in equation 1 as: m.sub.1.DELTA.V.sub.1=m.sub.2.DELTA.V.sub.2+F.DELTA.t [1] where m.sub.1 and m.sub.2 are the masses of subject vehicles one and two, respectively, and .DELTA.V.sub.1 and .DELTA.V.sub.2 are the change in velocities for subject vehicles one and two, respectively. F.DELTA.t is a vector and accounts for external forces, such as tire forces, acting on the system during the collision and is assumed to be zero unless otherwise known.

The crash based .DELTA.V's for each vehicle are used to estimate a .DELTA.V for the other vehicle. For example, the crash based .DELTA.V's for a first subject vehicle are inserted as .DELTA.V.sub.1 in equation 1 and used by conservation of momentum operation 212 to estimate .DELTA.V's for the second subject vehicle, and visa versa. The .DELTA.V's estimated by conservation of momentum operation 212 for the two subject vehicles are compared to the .DELTA.V's estimated by crash test .DELTA.V operation 210, respectively, in conservation of momentum based/crash test based .DELTA.V comparison operation 213. If the .DELTA.V's from crash test .DELTA.V operation 210 and conservation of momentum operation 212 are in closer agreement for the first subject vehicle than the similarly compared .DELTA.V's for the second subject vehicle, then .DELTA.V's estimated in crash test .DELTA.V operation 210 for the second subject vehicle are used in multi-method .DELTA.V combination generator 232, and the conservation of momentum operation 212 based .DELTA.V's are utilized in multi-method .DELTA.V combination generator 232 for the first subject vehicle. Likewise, if the .DELTA.V's from crash test .DELTA.V operation 210 and conservation of momentum operation 212 are in closer agreement for the second subject vehicle than the similarly compared .DELTA.V's for the first subject vehicle, then .DELTA.V's estimated in crash test .DELTA.V operation 210 for the first subject vehicle are used in multi-method .DELTA.V combination generator 232, and the conservation of momentum operation 212 based .DELTA.V's are utilized in multi-method .DELTA.V combination generator 232 for the second subject vehicle.

If only one of the subject vehicles has an applicable crash test(s), the .DELTA.V's estimated in crash test .DELTA.V operation 210 are used by conservation of momentum operation 212 to estimate the .DELTA.V's for the other subject vehicle using equation 1 as described above.

Data Acquisition for Computationally Estimated .DELTA.V

As discussed in more detail below, the .DELTA.V determination module 200 utilizes a .DELTA.V data acquisition module 214 to estimate .DELTA.V for a subject vehicle in addition to the above described crash test based .DELTA.V estimated. The .DELTA.V computation module utilizes data input from users in the .DELTA.V data acquisition module 214. Conventionally, the Campbell method provides an exemplary method to calculate subject vehicle .DELTA.V; see Campbell, K., Energy Basis for Collision Severity, Society of Automotive Engineers Paper #740565, 1974, which is incorporated herein by reference in its entirety. Data entry used for conventional programs to determine .DELTA.V generally required knowledge of parameters used in .DELTA.V calculations and generally required the ability to make reasonable estimates and/or assumptions in reconstructing the subject vehicle accident.

Referring to FIG. 5, the .DELTA.V data acquisition module 214 enables users who are not trained engineers or accident reconstructionists to enter data necessary for estimating AV. The .DELTA.V data acquisition module 214 allows a user to enter three-dimensional information from a two-dimensional generated interface. The .DELTA.V data acquisition module 214 generates a graphical user interface 500 having a grid pattern 504 superimposed above the bumper of a representative subject vehicle 502, which in this embodiment is a Chevrolet Suburban C20.TM.. The grid pattern includes eight (8) zones divided into columns, labeled A H, respectively, and two rows. The user selects, using an I/O device 112 such as a mouse, grid areas which directly correspond to observed c