Position-determination system for an elevator

Patent metadata

Field	Value
Publication number	US-10577220-B2
Application number	US-201515534596-A
Country	US
Kind code	B2
Filing date	Dec 14, 2015
Priority date	Dec 16, 2014
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

A position-determination system for an elevator uses a camera arranged on an elevator car, which camera has a sensor with a defined number of light-sensitive pixels for generating image data of a surface structure of hoistway material arranged along a travel path of the elevator car. An analysis unit, based on the image data, determines a position and/or velocity of the elevator car. The position-determination system recognizes a reference pattern with a specified dimension which lies in a capturing range of the camera, wherein, based on the reference pattern, the analysis unit performs a scaling of the image data.

First claim

The invention claimed is:

1. A position-determination system for an elevator with an elevator car movable along a travel path in a hoistway, comprising:
a camera arranged on the elevator car and having a sensor with a defined number of light-sensitive pixels, the camera generating by the sensor image data of a surface structure of hoistway material arranged along the travel path of the elevator car;
an analysis unit that determines at least one of a position of the elevator car and a velocity of the elevator car in the hoistway based on the image data; and
wherein the position-determination system recognizes a reference pattern with a specified dimension, wherein the reference pattern lies in a capturing range of the camera, and wherein the analysis unit performs a calibration of the sensor based on a determination of a dimension of the reference pattern in the image data.

2. The position-determination system according to claim 1 wherein for the calibration of the sensor, the analysis unit sets the specified dimension of the reference pattern in relation to a number of the pixels that represent the specified dimension as an image.

3. The position-determination system according to claim 2 wherein when determining the position or the velocity by the relation that is derived from the calibration, the generated image data are scalable.

4. The position-determination system according to claim 1 wherein the camera has an adjustable analysis range in which the image data are captured, wherein the analysis range lies within the capturing range, wherein the analysis range can be adjusted to be smaller than the capturing range, and wherein the reference pattern lies within the analysis range.

5. The position-determination system according to claim 4 wherein the camera has an adjustable position-determination range in which the image data are capturable, and wherein the analysis unit determines the position or the velocity of the elevator car by a comparison of the generated image data with image data of a reference image that is identified to a position that lies in the analysis range and wherein the position-determination range is adjustable to be smaller than the analysis range.

6. The position-determination system according to claim 1 including a light-source that generates the reference pattern on the surface structure, wherein the reference pattern lies in the capturing range of the camera.

7. The position-determination system according to claim 6 wherein the reference pattern contains at least two light-points that are generated in a specified dimension separation from each other on the surface structure, wherein, based on the separation between the two light-points, the analysis unit performs the calibration of the sensor.

8. The position-determination system according to claim 6 wherein the camera has an adjustable analysis range in which the image data are captured, wherein the analysis range lies within the capturing range, wherein the camera has an adjustable position-determination range in which the image data are capturable, wherein the adjustable position-determination range lies within the analysis range, wherein the reference pattern lies within the analysis range, wherein the light-source generates the reference pattern on the surface structure as an upper light-point that lies above the position-determination range and a lower light-point that lies below the position-determination range.

9. The position-determination system according to claim 6 wherein the reference pattern contains at least two light-points that are generated in a specified dimension separation from each other on the surface structure, wherein, based on the separation between the two light-points, the analysis unit performs the calibration of the sensor, and wherein the two light-points are vertically offset on the surface structure.

10. The position-determination system according to claim 6 wherein the light-source contains a first laser diode that emits a first laser beam and a second laser diode that emits a second laser beam, wherein the first laser beam generates a first light-point on the surface structure and the second laser beam generates a second light-point on the surface structure.

11. The position-determination system according to claim 10 wherein the first laser beam and the second laser beam are aligned mutually parallel.

12. The position-determination system according to claim 10 wherein at least two of the first laser diode and the second laser diode, the sensor, and a lens of the camera are integrated on a circuit board.

13. The position-determination system according to claim 1 wherein the reference pattern is a reference object that is arranged on the surface structure, and wherein the reference object lies in the capturing range of the camera when the elevator car is positioned at an associated portion of the travel path.

14. The position-determination system according to claim 13 wherein the reference object is one of a screw-head, a rail-fastening element, and a code-mark.

15. An elevator with the elevator car and the position-determination system according to claim 1 where in the analysis unit transmits the position of the elevator car or the velocity of the elevator car to an elevator control, wherein the elevator control, using of the position or the velocity, controls a drive unit to cause the elevator car to travel along the travel path.

Assignees

• Inventio Ag

Inventors

• Bitzi Raphael
• Scherrer Daniel
• Brossi Steven

Classifications

• G06T2207/10028

  Range image; Depth image; 3D point clouds · CPC title

• B66B1/3492 Primary

  Position or motion detectors or driving means for the detector (B66B1/40, B66B1/50 take precedence; length measuring G01B; speed measuring G01P) · CPC title

• B66B5/0018

  Devices monitoring the operating condition of the elevator system · CPC title

• G01B11/022

  by means of tv-camera scanning · CPC title

• G06T7/80

  Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration · CPC title