System and method of interactive evaluation and manipulation of a geometric model

• US 6,801,187 B2
• Filed: 06/22/2001
• Issued: 10/05/2004
• Est. Priority Date: 06/22/2001
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Chen, Yifan, Buttolo, Pietro, Stewart, Paul Joseph
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Laneau, Ronald
• Application Number:
  US09/888,120
• Publication Number:
  US 20030011561A1
• Time in Patent Office: 1,201 Days
• Field of Search: 345/156, 345/157, 345/161, 345/167, 345/420, 345/701, 345/702, 700/29, 700/182
• US Class Current: 345/156
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2210/28 Force feedback

Abstract

A system and method of interactive evaluation and manipulation of a geometric model is provided. The system includes a computer system and a haptic interface operatively in communication with the computer system, whereby the haptic interface includes a haptic end effector device for transmitting information between a user and a geometric model as the user browses or edit the surface of the geometric model using the haptic end effector device.

Claims

1. A system of interactive evaluation and manipulation of a geometric model comprising:

a computer system, wherein said computer system includes a memory, a processor, a user input device and a display device;

a computer generated geometric model stored in said memory of said computer system; and

a haptic interface operatively in communication with said computer system, wherein said haptic interface includes a haptic end effector device for transmitting information between a user and said geometric model, wherein the user browses or edits the surface of said geometric model using said haptic end effector device, wherein in browsing said surface of said geometric model a stick-to-surface force and property-feedback force are applied to control a location and force output of said haptic end effector device, wherein in editing the surface of said geometric model a haptic device position and orientation on a surface of said geometric model is determined and mapped into a geometric model coordinate reference system, a closest point on the surface of said geometric model to the haptic device position is identified, a surface position of the closest point position is determined, and the surface in the neighborhood of the closest point is edited by converging the closest point on the edited point, a surface property in the neighborhood of the closest point position is edited, and a stick-to-surface/stick-to-pen force and a property-feedback force are determined and applied to said haptic end effector device to constrain a hand of a user to a surface of said geometric model.

2. A system as set forth in claim 1 including a virtual reality display mechanism operatively in communication with said computer system and said haptic interface so the user can see said geometric model in a virtual environment.

3. A system as set forth in claim 1 wherein said haptic interface tactilely conveys a surface property of said geometric model to the user through said haptic end effector device and said haptic end effector device is constrained to the surface of said geometric model and the surface is constrained to said haptic device.

4. A method of interactive evaluation and manipulation of a geometric model, said method comprising the steps of:

browsing a surface of the geometric model using a haptic end effector device operatively connected to a haptic interface, wherein a stick-to-surface force and property-feedback force are applied to control a location and force output of the haptic end effector device while a user is browsing the surface of the geometric model;

determining if the user is signaling to edit the surface of the geometric model;

continuing to browse the surface of the geometric model is the user is not signaling to edit the surface of the model;

editing the surface of the geometric model if the user is signaling to edit the surface of the geometric model;

determining a haptic end effector device position on the surface of the geometric model while editing;

mapping the haptic end effector device position into a coordinate reference frame for the geometric model while editing;

identifying a closest point to edit on the surface of the geometric model to the haptic end effector device position while editing;

determining if the user is editing a fixed point or a non-fixed point in a parametric space on the surface;

editing a fixed point by determining a surface position and property of the closest point, and modifying the geometry of the surface until the closest point converges on the haptic end effector device position;

editing a non-fixed point by decomposing the haptic end effector device position into editing and browsing components, finding a new surface position on the geometric model using a previous surface position and haptic end effector device position, and modifying the geometry of the surface until the closest point converges on the haptic end effector device position;

editing a surface property in the neighborhood of the closest point;

determining a stick-to-surface/stick-to-pen force and a property feedback force using the surface property in the neighborhood of the closest point; and

applying the stick-to-surface/stick-to-pen force and property feedback force at the closest point to control a location and force output of the haptic end effector device.

5. A method as set forth in claim 4 including the step of selecting a geometric model from a database in the memory of the computer system prior to said step of acquiring the haptic device position, wherein the geometric model is a computer-aided design model.

6. A method as set forth in claim 4 wherein said step of browsing a surface of the geometric model includes the steps of:

acquiring a haptic end effector device position with respect to a surface of the geometric model, wherein the haptic end effector device is operatively connected to a haptic interface and the geometric model is stored in a memory of a computer system;

mapping the haptic end effector device position into a geometric model coordinate reference system;

determining a closest point position on the surface of the geometric model to the haptic device position;

extracting a surface property at the closest point position;

determining a stick-to-surface force and a property feedback force using the surface property at the closet point position; and

applying the stick-to-surface force and property feedback force at the closest point to control a location and force output of the haptic end effector device.

7. A method as set forth in claim 4 wherein said step of signaling to edit includes the user signaling to edit by manipulating the haptic end effector device to exert a predetermined strength on the surface.

8. A method as set forth in claim 4 wherein said step of editing a fixed point includes the steps of:

acquiring a haptic device position with respect to a surface of the geometric model, wherein the haptic end effector device is operatively connected to a haptic interface and the geometric model is stored in a memory of a computer system;

mapping the haptic end effector device position into a geometric model coordinate reference frame;

determining a closest point position on the surface of the geometric model to the haptic end effector device position;

determining a surface property at the closest point position; and

mapping the surface properties into a vector representing position.

9. A method as set forth in claim 4 wherein said step of editing a non-fixed point includes the steps of:

acquiring a haptic end effector device position with respect to a surface of the geometric model;

mapping the haptic device position into a geometric model coordinate reference frame;

finding a new surface position using a previous closest point position and haptic end effector device position;

determining surface properties at the closest point position; and

mapping the surface properties into a vector representing position.

10. A method as set forth in claim 4 wherein said step of applying a stick-to-surface/stick-to-pen force and a property feedback force includes the step of tactilely conveying a surface property of the geometric model to a user through the haptic end effector device and constraining the haptic end effector device to the surface of the geometric model, and the surface of the geometric model to the haptic end effector device.

11. A method as set forth in claim 4 wherein the user views the surface of the geometric model using a virtual reality display mechanism in communication with the computer system and the haptic interface.

12. A method of interactive evaluation and manipulation of a geometric model, said method comprising the steps of:

browsing a surface of the geometric model using a haptic end effector device operatively connected to a haptic interface, wherein a stick-to-surface force and property-feedback force are applied to control a location and force output of the haptic end effector device while a user is browsing the surface of the geometric model;

determining if the user is signaling to edit the surface of the geometric model;

continuing to browse the surface of the geometric model is the user is not signaling to edit the surface of the model;

editing the surface of the geometric model if the user is signaling to edit the surface of the geometric model;

determining a haptic end effector device position and orientation on the surface of the geometric model while editing;

mapping the haptic end effector device position and orientation into a coordinate reference frame for the geometric model while editing;

identifying a closest point to edit position and orientation on the surface of the geometric model to the haptic end effector device position and orientation while editing;

determining if the user is editing a fixed point or a non-fixed point in parametric space on the surface;

editing a fixed point by determining a surface position and property of the closest point position and orientation and modifying the geometry of the surface until the closest point position and orientation converges on the haptic end effector device position;

editing a non-fixed point by decomposing the haptic end effector device position and orientation into editing and browsing components, finding a new surface position and orientation on the geometric model using a previous surface position and haptic end effector device position and orientation, and modifying the geometry of the surface until the closest point position converges on the haptic end effector device position;

editing a surface property in the neighborhood of the closest point;

determining a stick-to-surface/stick-to-pen force and a property feedback force using the surface property in the neighborhood of the closest point; and

applying the stick-to-surface/stick-to-pen force and property feedback force at the closest point to control a location and force output of the haptic end effector device.

13. A method as set forth in claim 12 including the step of selecting a geometric model from a database in the memory of the computer system prior to said step of acquiring the haptic device position and orientation, wherein the geometric model is a computer-aided design model.

14. A method as set forth in claim 12 wherein said step of browsing a surface of the geometric model includes the steps of:

acquiring a haptic end effector device position and orientation with respect to a surface of the geometric model, wherein the haptic end effector device is operatively connected to a haptic interface and the geometric model is stored in a memory of a computer system;

mapping the haptic end effector device position and orientation into a geometric model coordinate reference system;

determining a closest point position and orientation on the surface of the geometric model to the haptic device position;

extracting a surface property at the closest point position and orientation;

determining a stick-to-surface force and a property feedback force using the surface property at the closet point position and orientation; and

applying the stick-to-surface force and property feedback force at the closest point to control a location and force output of the haptic end effector device.

15. A method as set forth in claim 12 wherein said step of signaling to edit includes the user signaling to edit by manipulating the haptic end effector device to exert a predetermined strength on the surface.

16. A method as set forth in claim 12 wherein said step of editing a fixed point includes the steps of:

acquiring a haptic device position and orientation with respect to a surface of the geometric model, wherein the haptic end effector device is operatively connected to a haptic interface and the geometric model is stored in a memory of a computer system;

mapping the haptic end effector device position and orientation into a geometric model coordinate reference frame;

determining a closest point position and orientation on the surface of the geometric model to the haptic end effector device position;

determining a surface property at the closest point position and orientation; and

mapping the surface properties into a vector representing position and orientation.

17. A method as set forth in claim 12 wherein said step of editing a non-fixed point includes the steps of:

acquiring a haptic end effector device position and orientation with respect to a surface of the geometric model;

mapping the haptic end effector device position and orientation into a geometric model coordinate reference frame;

finding a new surface position using a previous closest point position and haptic end effector device position and orientation;

determining surface properties at the closest point position and orientation; and

mapping the surface properties into a vector representing position and orientation.

18. A method as set forth in claim 12 wherein said step of applying a stick-to-surface/stick-to-pen force and a property feedback force includes the step of tactilely conveying a surface property of the geometric model to a user through the haptic end effector device and constraining the haptic end effector device to the surface of the geometric model, and the surface of the geometric model to the haptic end effector device.

19. A method as set forth in claim 12 wherein the user views the surface of the geometric model using a virtual reality display mechanism in communication with the computer system and the haptic interface.

20. A method as set forth in claim 19 wherein the computer system, haptic interface and virtual reality display mechanism are in communication with each other.