Sensor for automatic doors

• US 6,756,910 B2
• Filed: 02/27/2002
• Issued: 06/29/2004
• Est. Priority Date: 02/27/2001
• Status: Expired due to Term

• Current Assignee: Optex Company Limited (OPTEX GROUP Co., Ltd.)
• Original Assignee: Optex Company Limited (OPTEX GROUP Co., Ltd.)
• Inventors: Imanishi, Osamu, Ohba, Hiroyuki, Imuro, Yoshihiro, Kurata, Mataichi
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Nguyen, Tai T.
• Application Number:
  US10/083,571
• Publication Number:
  US 20020118114A1
• Time in Patent Office: 853 Days
• Field of Search: 340/686.6, 340/686.1, 340/573.1, 340/540, 340/500, 382/106, 382/103, 382/100, 348/155, 348/152, 348/143, 318/286, 318/626
• US Class Current: 340/686.6
• CPC Class Codes: E05F 15/43 responsive to disruption of energy beams, e.g. light or sound
• CPC Class Codes: E05F 15/73 responsive to movement or presence of persons or objects
• CPC Class Codes: E05F 2015/434 with cameras or optical sensors
• CPC Class Codes: E05F 2015/767 using cameras
• CPC Class Codes: E05Y 2900/132 Doors
• CPC Class Codes: G01V 8/10 Detecting, e.g. by using light barriers by reflection from the object G01S17/00

Abstract

Cameras take images of a predetermined area around a door. A distance measurement unit measures a distance from the cameras to each object in the taken images. Based on the measured distance, a floor detection unit detects a floor, and an object height/position detection unit detects a height and position of any object other than the floor. A door position detection unit and a door position identification unit 57 specify position of the door (i.e. open or closed) in the images taken by the cameras. A judgement unit judges presence or absence of an object which is neither the floor nor the door. If an object other than the floor and the door is observed in the images taken by the cameras, an output unit produces an object detection signal, so that the door is kept in an open state.

Claims

1. A sensor for an automatic door, comprising:

image pickup means for taking an image of a predetermined area around a door;

distance measurement means for, upon receiving an output from said image pickup means, measuring a distance between said image pickup means and each object which is in the predetermined area and observed in the image taken of the predetermined area;

object identification means for, upon receiving an output from said distance measurement means, identifying each object in the predetermined area, for which the distance between it and said image pickup means has been measured, as a background object or an object other than the background object based on the measured distance, and identifying the object other than the background object as the door or an object other than the door; and

output means for, upon receiving an output from said object identification means, outputting an object detection signal for an object that is observed in the image taken of the predetermined area and is neither the background object nor the door.

2. The sensor for an automatic door according to claim 1,

wherein the sensor is associated with door drive control means for controlling an open/close drive of the door, and

wherein said output means is for outputting the object detection signal to said door drive control means so as to cause the door to open fully.

3. The sensor for an automatic door according to claim 2,

wherein said image pickup means includes plural image pickup elements;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements.

4. The sensor for an automatic door according to claim 2,

wherein said image pickup means has a variable focus lens;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object.

5. The sensor for an automatic door according to claim 1,

wherein said image pickup means includes plural image pickup elements;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements.

6. The sensor for an automatic door according to claim 1,

wherein said image pickup means has a variable focus lens;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object.

7. A sensor for an automatic door, comprising:

image pickup means for taking an image of a predetermined area which covers a track of a door;

distance measurement means for, upon receiving an output from said image pickup means, measuring a distance between said image pickup means and each object which is in the predetermined area and observed in the image taken of the predetermined area;

floor detection means for, upon receiving an output from said distance measurement means, detecting a floor and a height and position of the floor such that the floor is distinguished from objects for which the distance between these objects and said image pickup means has been measured;

object height/position detection means for, upon receiving outputs from said distance measurement means and said floor detection means, detecting a height and position of an object, other than the floor, which is in the predetermined area and observed in the image taken of the predetermined area, and is located at a different height and position relative to the height and position of the floor;

door position detection means for detecting whether the door is in an open position or a closed position along the track;

door position identification means for, upon receiving an output from said door position detection means, identifying a position of the door in the image taken of the predetermined area, based upon whether the door is in an open position or a closed position as detected by said door position detection means;

judgement means for, upon receiving outputs from said object/height position detection means and said door position identification means, judging whether the object, which is other than the floor, is the door or an object other than the door; and

output means for, upon receiving an output from said judgement means, outputting an object detection signal for an object that is observed in the image taken of the predetermined area and is neither the floor nor the door.

8. The sensor for an automatic door according to claim 7,

wherein the sensor is associated with door drive control means for controlling an open/close drive of the door along the track and for producing an output signal which corresponds to the position of the door, and

wherein said door position detection means is for receiving the output signal from said door drive control means so as to determine whether the door is in an open position or a closed position.

9. The sensor for an automatic door according to claim 7,

wherein said door position detection means is for determining whether the door is in an open position or a closed position based on the image of the predetermined area taken by said image pickup means.

10. The sensor for an automatic door according to claim 7,

wherein the sensor is associated with door drive control means for controlling an open/close drive of the door along the track, and

wherein said output means is for outputting the object detection signal to said door drive control means so as to cause the door to open fully.

11. The sensor for an automatic door according to claim 10,

wherein said image pickup means includes plural image pickup elements;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements.

12. The sensor for an automatic door according to claim 10,

wherein said image pickup means has a variable focus lens;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object.

13. The sensor for an automatic door according to claim 7,

wherein said image pickup means includes plural image pickup elements;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements.

14. The sensor for an automatic door according to claim 7,

wherein said image pickup means has a variable focus lens;

and

wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object.