Particle impact and soil deposition analysis system and method for vehicle design

• US 6,529,860 B1
• Filed: 10/19/1998
• Issued: 03/04/2003
• Est. Priority Date: 10/19/1998
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Babu, Viswanathan, Strumolo, Gary Steven
• Primary Examiner(s): JONES, HUGH M
• Application Number:
  US09/176,268
• Time in Patent Office: 1,597 Days
• Field of Search: 395/500.29, 395/500.3, 703/8, 703/9
• US Class Current: 703/8
• CPC Class Codes: G06F 2111/10 Numerical modelling
• CPC Class Codes: G06F 30/15 Vehicle, aircraft or watercraft design
• CPC Class Codes: G06F 30/23 using finite element methods [FEM] or finite difference methods [FDM]
• CPC Class Codes: Y02T 90/00 Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation

Abstract

A method and system for aiding in the design of an automotive vehicle enables dynamic placement of particle injection points relative to a computer aided design model representative of the vehicle to permit visual observation and alteration of resulting particle trajectories with respect to the model. Various particle trajectories, representing stones ejected from a tire toward the vehicle surface, soil deposition patterns, and the like can be simulated relative to the vehicle surface to evaluate a vehicle design, compare alternate designs and compare results from physical aerodynamic tests to predicted results.

Claims

1. A system for designing an automotive vehicle by enabling dynamic placement of particle injection points relative to a vehicle surface to permit visual observation and alteration of resulting particle trajectories over a computer aided design (CAD) model representative of a desired portion of the vehicle represented on a display means by a computer having memory means, processor means and user input means associated therewith, the system comprising:

particle injector placement code means operable with the user input means to dynamically effect a desired placement of at least one particle injector on the display means with respect to the desired portion of the CAD model;

trajectory determination code means for computing at least one trajectory for a particle stream emanating from the at least one particle injector relative to the desired portion of the CAD model for user inputable information describing the physical particle characteristics in a predetermined set of particle external conditions;

trajectory display code means for effecting display of the at least one trajectory with respect to the desired portion of the CAD model; and

a damage analysis means for estimating damage caused by the impact of the particle stream at a user-selected location of the vehicle and for displaying information representative of the estimated damage.

2. The system of claim 1 wherein the particle injector placement code means includes GUI means for displaying a particle injector GUI on the display means, the GUI means operative with the input means for locating the desired placement of the at least one particle injector.

3. The system of claim 1 wherein the predetermined set of particle characteristics includes at least one of a set of particle diameter data, particle density data, and particle initial velocity data.

4. The system of claim 1 wherein the trajectory display code means includes code means for displaying coordinate information on the display means relative to the CAD model for intersection of the at least one trajectory with the desired portion of the vehicle.

5. The system of claim 1 wherein the particle injector placement code means includes stone injector code means for simulating ejection of particles from a predetermined tire patch of a tire of the CAD vehicle.

6. The system of claim 5 wherein the trajectory determination code means includes ejected stone code means for determining a set of data representing particle impact data including at least one of a set of impact angle, a set of impact velocity data, a set of impact frequency data, and set of impact damage estimate data for each of a set of stone particles ejected by the particle injector from the tire patch, and wherein the particle impact data is utilized by the damage analysis means to estimate damage caused by the ejected particles at the user-selected location of the vehicle.

7. The system of claim 6 wherein the trajectory display code means includes ejected stone display means for displaying at least one item of the set of particle impact data on the display means, including particle impact points at the user-selected location of vehicle, and wherein the damage analysis means is effective to vary the color of displayed impact points based upon the estimated damage at the impact points.

8. The system of claim 1 wherein the particle injector placement code means includes soil deposition code means for simulating ejection of soil particles from a predetermined tire patch of a tire of the CAD vehicle.

9. The system of claim 8 wherein the trajectory determination code means includes soil deposition pattern code means for determining a set of data representing soil deposition data including at least one of a set of soil impact angle data, a set of soil spray diffusion data, and a set of soil impact frequency data for each of a set of soil deposition streams ejected by the particle injector from the tire patch.

10. The system of claim 9 wherein the trajectory display code means includes soil deposition display means for displaying at least one item of the set of soil deposition data on the display means relative to the desired portion of the CAD model.

11. A method for designing an automotive vehicle using particle trajectory analysis with a computer aided design (CAD) model representative of the vehicle, the method comprising the steps of:

preparing a CAD model of a desired portion of the vehicle;

placing a particle injector at a desired location with respect to the desired portion of the vehicle;

specifying particle information describing the physical characteristics of particles to be ejected from the particle injector;

computing a trajectory for a particle stream emanating from the particle injector;

displaying the trajectory relative to the desired portion of the vehicle on a display means to permit visual observation thereof;

determining points on a surface of the vehicle that are impacted by the particle stream;

calculating damage information relating to the impact of the particle stream on the surface of the vehicle;

displaying the calculated damage information; and

repositioning the particle injector if necessary to achieve a desired trajectory.

12. A method for designing an automotive vehicle by enabling dynamic placement of particle injection points into a flow domain to permit visual observation and alteration of resulting particle trajectories with respect to a computer aided design (CAD) model representative of the vehicle, the method of comprising the steps of:

storing a first set of data representing a CAD model of a desired portion to the vehicle into a computer memory;

displaying the first set of data on a video display screen;

placing at least one particle injector at a desired location with respect to the desired portion of the vehicle by storing a second set of data representing the at least one particle injector in the computer memory;

storing a third set of data in the computer memory representing particle information describing the physical characteristics of the particles to be ejected from the particle injector;

computing a fourth set of data representing a stationary trajectory for a particle stream emanating from the particle injector using the first, second and third sets of data;

displaying the fourth set of data representing a trajectory relative to the first set of data representing a desired portion of the vehicle on the video display screen to permit visual observation thereof;

computing a fifth set of data representing particle impact data describing particle impact points and attributes at a user-selected location on a surface of the vehicle;

utilizing the fifth said of data to estimate damage to the user-selected location on the surface of the vehicle;

displaying damage information describing the estimated damaged to the user-selected location on the surface of the vehicle; and

dynamically repositioning the particle injector if necessary to achieve a desired trajectory by manipulating the second set of data in the computer memory.

13. The method of claim 12 wherein the third set of data representing particle information includes at least one of a set of particle diameter data, particle density data, and particle initial velocity data.

14. The method of claim 12 and further including the step of displaying coordinate information on the video display screen relative to the CAD model for intersection of the trajectory with the desired portion of the vehicle.

15. The method of claim 12 wherein particle injector is placed in the desired location using a screen GUI displayed on the display means.

16. The method of claim 12 wherein the second set of data represents a stone injector for simulating ejection of particles from a predetermined tire patch of a tire of the CAD vehicle.

17. The method of claim 12 wherein the damage information is directly displayed on the surface of the vehicle.

18. The method of claim 17 wherein the damage information displayed includes particle impact points which vary in color according to the estimated damage at the impact points.

19. The method of claim 12 wherein the second set of data represents a soil deposition injector for simulating ejection of particles from a predetermined tire patch of a tire of the CAD vehicle.

20. The method of claim 19 including the step of computing a fifth set of data representing particle impact data including at least one of a set of soil impact angle data, a set of soil spray diffusion data, and a set of soil impact frequency data for each of a set of soil deposition streams ejected by the particle injector from the tire patch.