Contactless obstacle detection for power doors and the like

• US 8,589,033 B2
• Filed: 01/11/2008
• Issued: 11/19/2013
• Est. Priority Date: 01/11/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Rafii, Abbas, New, Richard, Acharya, Sunil, Droz, Timothy
• Primary Examiner(s): Rocca, Joseph
• Assistant Examiner(s): SPISICH, GEORGE D
• Application Number:
  US12/008,430
• Publication Number:
  US 20110295469A1
• Time in Patent Office: 2,139 Days
• Field of Search: 701/49, 356/141.1, 356 401- 515, 348/402.1, 348/313, 348/143, 49 26- 28, 342/450, 318/280, 318/286, 318/362, 318/466, 340/435, 340/436
• US Class Current: 701/49
• CPC Class Codes: E05F 15/43 responsive to disruption of energy beams, e.g. light or sound
• CPC Class Codes: E05F 2015/434 with cameras or optical sensors
• CPC Class Codes: E05F 2015/483 for detection during opening
• CPC Class Codes: E05Y 2900/531 Doors
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/30248 Vehicle exterior or interior
• CPC Class Codes: G06T 7/254 involving subtraction of images

Abstract

Time-of-flight (TOF) three-dimensional sensing systems are deployed on or in a motor vehicle to image contact zones associated with potential contact between an avoidable object and the vehicle or vehicle frame and/or remotely controllable motorized moving door or liftgate. An algorithm processes depth data acquired by each TOF system to determine whether an avoidable object is in the associated contact zone. If present, a control signal issues to halt or reverse the mechanism moving the door. A stored database preferably includes a depth image of the contact zone absent any object, an image of the door, and volume of the door. Database images are compared to newly acquired depth images to identify pixel sensors whose depth values are statistically unlikely to represent background or the door. Pixels within the contact zone so identified are an object, and the control signal is issued.

Claims

1. A method to contactlessly determine whether a movable door in a motor vehicle is at risk of contacting an avoidable object during door movement, the method comprising the following steps:

(a) for each said door, disposing at least one time-of-flight (TOF) system with a field of view (FOV) adequately wide to acquire in real-time at least one depth image of at least a portion of a three-dimensional contact zone within which an avoidable object, if present, would be contacted by at least part of said door when said door is moving, an avoidable object being an object excluding said door and a vehicle door frame associate with said door;

(b) providing said TOF system with a software executable algorithm that uses said depth image acquired at step (a) to determine whether at least a portion of an avoidable object is present within a portion of said contact zone when said door is moving such that door-avoidable object contact may occur unless prevented, said algorithm able to dynamically alter dimensions of said contact zone as a function of at least one door parameter; and

(c) generating a control signal if step (b) determines presence of at least a portion of said avoidable object within a portion of said contact zone, said control signal coupleable to a mechanism to facilitate at least one of (i) retarding present motion of said door, (ii) reversing direction of present motion of said door, and (iii) halting motion of said door;

whereby likelihood of damage resulting from contact between said avoidable object and said door is reduced, while ignoring other objects within said FOV.

2. The method of claim 1, wherein step (a) includes mounting said TOF system at a location selected from a group consisting of (i) on an interior portion of said motor vehicle, and (ii) on an exterior portion of said motor vehicle.

3. The method of claim 1, wherein step (a) includes mounting said TOF system at a location selected from a group consisting of (i) on an interior surface of said movable door, and (ii) on an exterior surface of said movable door.

4. The method of claim 1, wherein:

said TOF system includes a memory storing a previously acquired depth image of said contact zone absent any object therein; and

step (b) includes comparing said previously acquired depth image with said depth image acquired at step (a).

5. The method of claim 1, wherein:

said TOF system includes a memory storing previously acquired depth images of said contact zone absent any object therein, said depth images acquired at different permissible locations of said movable door as it moves through three-dimensional space.

6. The method of claim 1, wherein step (b) includes dynamically altering dimensions of said contact zone as a function of present door position.

7. The method of claim 1, wherein step (c) further includes coupling said control signal to a horn of said motor vehicle so as to sound an audible alarm.

8. The method of claim 1, wherein said movable door is selected from a group consisting of (i) a sliding side door, and (ii) a pivotable tailgate.

9. A system to contactlessly determine whether a movable door in a motor vehicle is at risk of contacting an avoidable object during door movement, the system comprising:

at least one time-of-flight (TOF) system with a field of view (FOV) adequately wide to acquire in real-time at least one depth image of at least a portion of a three-dimensional contact zone within which an avoidable object, if present, would be contacted by at least part of said door when said door is moving, an avoidable object being excluding said door and a vehicle door frame associated with said door, said TOF system disposed on said motor vehicle so as to obtain said at least one depth image;

a processor;

memory, executable by said processor, storing at least a software executable algorithm that uses said acquired depth image to determine whether at least a portion of an avoidable object is present within a portion of said contact zone when said door is moving such that door-avoidable object contact may occur unless prevented, said algorithm able to dynamically alter dimensions of said contact zone as a function of at least one door parameter; and

said algorithm generating a control signal if said algorithm determines presence of at least a portion of said avoidable object within a portion of said contact zone, said control signal coupleable to a mechanism to facilitate at least one of (i) retarding present motion of said door, (ii) reversing direction of present motion of said door, and (iii) halting motion of said door;

whereby likelihood of damage resulting from contact between said avoidable object and said door is reduced.

10. The system of claim 9, wherein said TOF system is mounted at a location selected from a group consisting of (i) on an interior portion of said motor vehicle, and (ii) on an exterior portion of said motor vehicle.

11. The system of claim 9, wherein said TOF system is mounted at a location selected from a group consisting of (i) on an interior surface of said movable door, and (ii) on an exterior surface of said movable door.

12. The system of claim 9, wherein:

said memory stores a previously acquired depth image of said three-dimensional space absent any object therein; and

said algorithm compares said previously acquired depth image with said depth image acquired by said TOF system.

13. The system of claim 9, wherein:

said memory stores previously acquired depth images of said contact zone absent any object therein, said depth images acquired at different permissible locations of said movable door as it moves through three-dimensional space.

14. The system of claim 9, wherein said algorithm dynamically alters volume of said contact zone as a function of at least one dynamic parameter of f said moving door.

15. The system of claim 9, wherein said algorithm dynamically alters dimensions of said contact zone as a function of present door position.

16. The system of claim 9, wherein said control signal is coupled to a horn of said motor vehicle so as to sound an audible alarm.

17. The system of claim 9, wherein said movable door is selected from a group consisting of (i) a sliding side door, and (ii) a pivotable tailgate.

18. A system to contactlessly determine whether a movable door in a motor vehicle is at risk of contacting an avoidable object during door movement, the system comprising:

at least one time-of-flight (TOF) system with a field of view (FOV) adequately wide to acquire in real-time at least one depth image of at least a portion of a three-dimensional contact zone within which an avoidable object, if present, would be contacted by at least part of said door when said door is moving, an avoidable object being an object excluding said door and a vehicle door frame associated with said door, said TOF system disposed on said motor vehicle so as to obtain said at least one depth image on a location selected from a group consisting of (i) an interior portion of said motor vehicle, (ii) an exterior portion of said motor vehicle, (iii) an interior portion of a sliding door of said motor vehicle, (iv) an exterior portion of a sliding door of said motor vehicle, (v) an interior portion of a pivotable tailgate of said motor vehicle, and (vi) an exterior portion of a pivotable tailgate of said motor vehicle;

a processor;

memory, executable by said processor, storing at least a software executable algorithm that uses said acquired depth image to determine whether at least a portion of an avoidable object is present within a portion of said contact zone when said door is moving such that door-avoidable object contact may occur unless prevented, said algorithm able to dynamically alter dimensions of said contact zone as a function of at least one door parameter; and

to generate a control signal if said algorithm determines presence of at least a portion of said avoidable object within a portion of said contact zone, said control signal coupleable to a mechanism to facilitate at least one of (i) retarding present motion of said door, (ii) reversing direction of present motion of said door, and (iii) halting motion of said door;

whereby likelihood of damage resulting from contact between said avoidable object and said door is reduced.

19. The system of claim 18, wherein:

said memory stores at least one of (i) a previously acquired depth image of said contact zone absent any object therein, and (ii) ; and

previously acquire depth images of said contact zone absent any object therein, said depth images acquired at different permissible locations of said movable door as it moves through three-dimensional space; and

said algorithm compares said previously acquired depth image with said depth image acquired by said TOF system.