Method for aligning one end of a passenger boarding bridge with a doorway of an aircraft

Abstract

A method for aligning one end of a passenger boarding bridge with a doorway of an aircraft includes sensing a location of a base plate of the doorway of the aircraft, using a sensor that is disposed proximate the one end of the passenger boarding bridge. A current location of the one end of the passenger boarding bridge is then determined relative to the sensed location of the base plate. Based upon a known relationship between the location of the doorway and the sensed location of the base plate, the one end of the passenger boarding bridge is moved from the current location toward the doorway of the aircraft. The method relies upon features of the aircraft itself and does not require additional passive or active targets on the aircraft.

Description

FIELD OF THE INVENTION

[0001] The instant invention relates to passenger boarding bridges, and more particularly to a method and system for aligning one end of a passenger boarding bridge with a doorway of an aircraft.

BACKGROUND

[0002] In order to make aircraft passengers comfortable, and in order to transport them between an airport terminal building and an aircraft in such a way that they are protected from the weather and from other environmental influences, passenger boarding bridges are used which are telescopically extensible and the height of which is adjustable. For instance, an apron drive bridge includes a plurality of adjustable modules, including: a rotunda, a telescopic tunnel, a bubble section, a cab, and elevating columns with wheel carriage. Other common types of passenger boarding bridges include radial drive bridges and over-the-wing (OTW) bridges. These types of passenger boarding bridges are adjustable, for instance to compensate for different sized aircraft and to compensate for imprecise parking of aircraft at an airport terminal.

[0003] Historically, the procedure for aligning the passenger boarding bridge with the doorway of an aircraft has been a time consuming and labor intensive operation. First, the pilot taxis the aircraft along a lead-in line to a final parking position within a gate area. Typically, the lead-in line is a physical marker that is painted onto the tarmac, and is used for guiding the aircraft along a predetermined path to a final parking position. Additional markings in the form of stop lines, one for each type of aircraft, are provided at predetermined positions along the lead-in line. Thus, when the nose gear of a particular type of aircraft stops precisely at the stop line for that type of aircraft, then the aircraft is known to be at its final parking position. Of course, the pilot's view of the tarmac surface from the cockpit of an aircraft is limited. This is particularly true for larger aircraft, such as for instance a Boeing 747-X00. Typically, in order to follow the lead-in line the pilot has relied upon instructions that are provided by a human ground marshal together with up to two "wing walkers". Optionally, stop bars are located on a pole that is fixedly mounted to the ground surface, including appropriate stop bars for each type of aircraft that uses the gate. Alternatively, a tractor or tug is used to tow the aircraft along the lead-in line to its final parking position.

[0004] More recently, sophisticated Visual Docking Guidance Systems have been developed to perform the function of the human ground marshal and wing walkers. In particular, a Visual Docking Guidance System (VDGS) senses the aircraft as it approaches the final parking position and provides instructions to the pilot via an electronic display device. The electronic display device is mounted at a location that makes it highly visible to the pilot when viewed from the cockpit of an aircraft. Typically, the instructions include a combination of alphanumeric characters and symbols, which the pilot uses to guide the aircraft precisely to the final parking position for the particular type of aircraft. The high capital cost of the VDGS system is offset by reduced labor costs and the efficiency that results from stopping the aircraft more precisely than is possible under the guidance of a human ground marshal.

[0005] Of course, even when the aircraft is stopped precisely at the final parking position for that type of aircraft, still there is the matter of moving the passenger boarding bridge into an aligned relationship with a doorway of the parked aircraft. In the case of an apron drive bridge this may involve extending the bridge by 10 to 20 meters or more from a stowed position. Unfortunately, driving the bridge over such a long distance is time consuming because often the rate at which the bridge is moved is limited so as to reduce the risk of colliding with ground service vehicles or personnel, and to avoid causing serious damage to the aircraft in the event of a collision therewith. Manual, semi-automated and automated bridge alignment systems are known for moving the passenger boarding bridge relative to the parked aircraft.

[0006] A manual bridge alignment system requires that a human operator is present to perform the alignment operation each time an aircraft arrives. Delays occur when the human operator is not standing-by to perform the alignment operation as soon as the aircraft comes to a stop. In addition, human operators are prone to making errors that result in the passenger boarding bridge being driven into the aircraft or into a piece of ground service equipment. Such collisions involving the passenger boarding bridge are costly and also result in delays. In order to avoid causing a collision, human operators tend to err on the side of caution and drive the passenger boarding bridge slowly and cautiously.

[0007] Semi-automated bridge alignment systems also require a human operator, but the human operator may be present at a remote location and interact with the bridge control system in a tele-robotic manner. One human operator may interact with a plurality of different passenger boarding bridges, thereby reducing the costs associated with training and paying the salaries of human operators. Alternatively, certain movements of the bridge are automated, whilst other movements are performed under the control of the human operator.

[0008] Automated bridge alignment systems provide a number of advantages compared to manual and semi-automated systems. For instance, automated bridge alignment systems do not require a human operator, and therefore the costs that are associated with training and paying the salaries of human operators are reduced or eliminated. Furthermore, an automated bridge alignment system is always standing by to control the passenger boarding bridge as soon as an aircraft comes to a stop. Accordingly, delays associated with dispatching a human operator to perform a bridge alignment operation are eliminated, particularly during periods of heavy aircraft traffic.

[0009] In U.S. Pat. No. 5,226,204, Schoenberger et al. disclose one type of automated system for aligning a passenger boarding bridge with a doorway of an aircraft. The system uses video cameras to capture images of the aircraft. The captured images are then provided to a computer for image processing. An object of the image processing is to use edge detection to locate the outline of the doorway along the lateral surface of the aircraft, and to determine the distance and direction from the bridge to the doorway. Unfortunately, the outline of the doorway does not provide a high contrast feature, and accordingly it may be difficult to locate the doorway within the image. In addition, the presence of scuffs, dirt, painted decals etc. near the doorway may make it difficult or impossible to correctly identify the outline of the doorway.

[0010] Another type of automated system is disclosed in published United States Patent Application 2005/0198750 A1, filed Feb. 26, 2003 in the name of Spencer et al. In particular, reflective targets are affixed to the exterior lateral surface of an aircraft around the doorway to which the passenger boarding bridge is to be aligned. A plurality of cameras disposed aboard the passenger boarding bridge is used to image the targets during the alignment procedure, with data relating to the images being provided subsequently to computer means for processing thereby. While the use of reflective targets for identifying the doorway of the aircraft is advantageous in that it simplifies image processing, never-the-less airlines are reluctant to apply targets to their aircraft and furthermore regulatory approval may be necessary to do so. In addition, the system is likely to fail if the targets become obscured due to dirt, scuffs, tearing or the build up of snow, etc. Furthermore, this approach relies upon every aircraft having the expected targets applied thereto. Absent the targets, it is not possible to align the passenger boarding bridge in an automated fashion.

[0011] In another approach to automating the passenger boarding bridge alignment operation, a beacon signal is used to guide the aircraft-engaging end of a passenger boarding bridge into alignment with an aircraft doorway. In U.S. Pat. Nos. 7,093,314, 6,757,927, 6,742,210 and 6,907,635, Hutton describes a transmitter or transceiver disposed aboard an aircraft for transmitting a signal including a beacon signal. A receiver aboard the passenger boarding bridge "homes in" on the beacon signal until the aircraft-engaging end of the passenger boarding bridge is aligned with the doorway of the aircraft. This approach relies upon every aircraft being equipped with an appropriate transmitter or transceiver. Absent the beacon signal, it is not possible to align the passenger boarding bridge in an automated fashion.

[0012] There has been an apparent trend in recent years toward developing automated passenger boarding bridge systems that rely upon additional passive or active targets, rather than features of the aircraft itself, for identifying the doorways of the aircraft. Accordingly, there is a long-standing and unfulfilled need for a bridge alignment system that is capable of aligning a passenger boarding bridge with an aircraft, absent intervention by a human operator, and absent additional passive or active targets being mounted aboard the aircraft. It would be advantageous to provide a system that overcomes at least some of the above-mentioned disadvantages of the prior art.

SUMMARY OF EMBODIMENTS OF THE INVENTION

[0013] In accordance with an aspect of the instant invention there is provided a method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: identifying the type and sub-type of the aircraft; positioning the one end of the passenger boarding bridge at a predefined position for the identified type and sub-type of the aircraft; using an imager disposed proximate the one end of the passenger boarding bridge, capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface; comparing the image data to template data for a doorway base plate of the identified type and sub-type of the aircraft; determining an instruction for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on the comparison of the image data with template data; and, automatically performing the instruction so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

[0014] In accordance with another aspect of the instant invention there is provided a method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: identifying the type and sub-type of the aircraft; positioning the one end of the passenger boarding bridge at a predefined position for the identified type and sub-type of the aircraft; sensing a current orientation of the one end of the passenger boarding bridge; using an imager disposed proximate the one end of the passenger boarding bridge, capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface; retrieving template data relating to the base plate of the doorway of the identified type and sub-type of the aircraft; scaling the retrieved template data based on the sensed current orientation of the one end of the passenger boarding bridge; determining an instruction for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on a comparison of the captured image data to the scaled template data; and, automatically performing the instruction so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

[0015] In accordance with another aspect of the instant invention there is provided a method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: sensing a location of a base plate of the doorway of the aircraft using a sensor that is disposed proximate the one end of the passenger boarding bridge; determining a current location of the one end of the passenger boarding bridge relative to the sensed location of the base plate; and, moving the one end of the passenger boarding bridge from the current location toward the doorway of the aircraft, based upon a known relationship between the location of the doorway and the sensed location of the base plate.

[0016] A system for aligning one end of a passenger boarding bridge with a doorway of an aircraft, the aircraft being parked adjacent to the one end of the passenger boarding bridge during a current alignment operation, the system comprising: an imager disposed proximate the one end of the passenger boarding bridge for capturing image data relating to a doorway base plate of the aircraft; a memory element having template image data stored therein, the template image data relating to the doorway base plate of the aircraft; and a processor in communication with the imager and with the memory element, for comparing the captured image data with the template image data and for determining an instruction for moving the one end of the passenger boarding bridge along a direction toward the doorway of the aircraft, based on a result of the comparison.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Exemplary embodiments of the invention will now be described in conjunction with the following drawings, in which similar reference numbers designate similar items:

[0018] FIG. 1 is a simplified block diagram showing image capture elements and image processing elements, according to an embodiment of the instant invention;

[0019] FIG. 2 is a simplified flow diagram of a method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention;

[0020] FIG. 3 is a simplified flow diagram of another method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention; and,

[0021] FIG. 4 is a simplified flow diagram of still another method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0022] The following description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments disclosed, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

[0023] According to at least one embodiment of the instant invention the base plate of an aircraft doorway is recognized as a feature for locating the doorway of the aircraft. To this end, an automated passenger boarding bridge control system is provided, which includes image capture elements and image processing elements such as for instance at least a digital camera. FIG. 1 shows a non-limiting example of suitable image capture elements and image processing elements. Optionally, a more complex vision system is provided such as for instance the one that is described by Hutton in a co-pending United States Patent Application entitled "Vision System For Automatically Aligning a Passenger Boarding Bridge with a Doorway of an Aircraft and Method Therefor", filed in October, 2006, the entire contents of which are herein incorporated by reference.

[0024] It is to be understood that the doorway base plate is a feature of the aircraft itself, and is made of a hard metal so as to endure passenger foot traffic during periods of boarding and deplaning. Typically, the base plate either is not painted, or if it is painted then at least some of the paint is worn off due to passengers stepping on or rolling luggage across the base plate. Accordingly, the base plate tends to be shiny and contrasts with adjacent portions of the aircraft fuselage, particularly when illuminated using a light source. It has now been recognized that the base plate is a suitable feature for identifying locations of doorways of the aircraft, which overcomes the need to provide passive or active targets for this purpose.

[0025] According to at least one embodiment of the instant invention, the type and sub-type of the aircraft is determined and data relating to the type and sub-type is provided to the automated passenger boarding bridge control system. For instance, a human operator provides the type and sub-type information in a manual fashion. Optionally, the type and sub-type is determined based on a comparison of sensed features of the aircraft with template data. The automated passenger boarding bridge control system then moves the passenger boarding bridge to a "photo position" such that the aircraft-engaging end of the passenger boarding bridge is adjacent to an expected stopping location of the doorway of the determined type and sub-type of the aircraft. An image is captured using an imager that is disposed proximate the aircraft engaging end of the passenger boarding bridge, and image data relating to the image is provided to an image data processor. Template data is retrieved from a memory element, the template data including at least one image of the doorway of the determined type and sub-type of aircraft. Preferably the template data includes a plurality of images of the doorway of the determined type and sub-type of aircraft. Optionally, at least some of the plurality of images includes paint pattern features of the doorway and surrounding portions of the aircraft fuselage. The template data is scaled based on a sensed orientation of the passenger boarding bridge relative to the aircraft. The captured image is compared to the scaled template data so as to match features relating to the base plate in the captured image data and the scaled template data. Based upon the comparison, horizontal and vertical movements of the passenger boarding bridge are determined for aligning the aircraft engaging end of the passenger boarding bridge with the doorway of the aircraft. Once the horizontal and vertical movements are performed, merely extending the length of the passenger boarding bridge completes the alignment operation.

[0026] Referring to FIG. 1, shown is a simplified block diagram of image data capture and image processing elements, according to an embodiment of the instant invention. An imager 10, such as for instance a typical CCD or CMOS digital camera, is provided at a location proximate the one end of the passenger boarding bridge. The imager 10 is in communication with an image processor 12, and provides captured image data thereto for subsequent processing, the captured image data relating to a doorway base plate of the aircraft. The image processor 12 is also in communication with a memory element 14 having template image data stored therein, the template image data relating to the doorway base plate of the aircraft. During use, the image processor 12 compares the captured image data with the template image data and, based on a result of the comparison, determines an instruction for moving the one end of the passenger boarding bridge along a direction toward the doorway of the aircraft. The image processor 12 provides an output signal including the instruction for controlling a not illustrated drive mechanism of the passenger boarding bridge. Based on the output signal, the not illustrated drive mechanism causes the one end of the passenger boarding bridge to move along the direction toward the doorway of the aircraft.

[0027] Optionally, a not illustrated light source is provided for illuminating the doorway base plate during image capture. Optionally, an orientation-sensing element such as for instance an inclinometer and/or a laser range finder is provided in communication with the image processor 12. Optionally, the imager 10 is provided in the form of a digital camera that is capable of imaging near infrared (near IR) and/or ultraviolet (UV), such as for instance a Fuji S3 UVIR. In this case, illumination using a light source may not be necessary or even desirable. Optionally, the imager 10 comprises a plurality of digital cameras. Of course, the imager 10 is not intended to be limited to only CCD or CMOS type digital cameras. Accordingly, it is envisaged that the imager 10 may utilize other types of image sensors that are capable of converting light into electrical signals.

[0028] Referring now to FIG. 2, shown is a simplified flow diagram of a method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention. At step 100 the type and sub-type of the aircraft is identified. At step 102 the one end of the passenger boarding bridge is positioned at a predefined position for the identified type and sub-type of the aircraft. At step 104 an imager disposed proximate the one end of the passenger boarding bridge is used for capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface. At step 106 the image data is compared to template data for a doorway base plate of the identified type and sub-type of the aircraft. At step 108 an instruction is determined for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on the comparison of the image data with template data. At step 110 the instruction is performed in an automated fashion so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

[0029] Referring now to FIG. 3, shown is a simplified flow diagram of another method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention. At step 200 the type and sub-type of the aircraft is identified. At step 202 the one end of the passenger boarding bridge is positioned at a predefined position for the identified type and sub-type of the aircraft. At step 204 a current orientation of the one end of the passenger boarding bridge is sensed relative to the aircraft. At step 206 an imager disposed proximate the one end of the passenger boarding bridge is used for capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface. At step 208 template data relating to the base plate of the doorway of the identified type and sub-type of the aircraft is retrieved. At step 210 the retrieved template data is scaled based on the sensed current orientation of the one end of the passenger boarding bridge relative to the aircraft. At step 212 an instruction is determined for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on a comparison of the captured image data to the scaled template data. At step 214 the instruction is performed in an automated fashion so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

[0030] Referring now to FIG. 4, shown is a simplified flow diagram of still another method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, according to an embodiment of the instant invention. At step 300 a location of a base plate of the doorway of the aircraft is sensed using a sensor that is disposed proximate the one end of the passenger boarding bridge. At step 302 a current location of the one end of the passenger boarding bridge is determined relative to the sensed location of the base plate. At step 304 the one end of the passenger boarding bridge is moved from the current location toward the doorway of the aircraft, based upon a known relationship between the location of the doorway and the sensed location of the base plate.

[0031] Numerous other embodiments may be envisaged without departing from the spirit and scope of the invention.

Claims

1. A method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: identifying the type and sub-type of the aircraft; positioning the one end of the passenger boarding bridge at a predefined position for the identified type and sub-type of the aircraft; using an imager disposed proximate the one end of the passenger boarding bridge, capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface; using an image processor in communication with the imager, comparing the image data to template data for a doorway base plate of the identified type and sub-type of the aircraft; determining an instruction for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on the comparison of the image data with template data; and, automatically performing the instruction so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

2. A method according to claim 1, wherein the imager is a digital camera and wherein capturing image data comprises providing a signal relating to the captured image data from the digital camera to the image processor.

3. A method according to claim 1, wherein the template data comprises a plurality of template images of the doorway base plate of the identified type and sub-type of the aircraft.

4. A method according to claim 3, wherein some of the plurality of template images include features of a paint pattern proximate the doorway of the aircraft.

5. A method according to claim 1, comprising sensing a current orientation of the one end of the passenger boarding bridge relative to the aircraft.

6. A method according to claim 5, wherein comparing the image data to template data comprises scaling the template data based on the sensed current orientation.

7. A method according to claim 5, wherein sensing the current orientation comprises sensing a distance from the imager to the aircraft.

8. A method according to claim 5, wherein sensing the current orientation comprises sensing tilt of the one end relative to a horizontal reference plane.

9. A method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: identifying the type and sub-type of the aircraft; positioning the one end of the passenger boarding bridge at a predefined position for the identified type and sub-type of the aircraft; sensing a current orientation of the one end of the passenger boarding bridge; using an imager disposed proximate the one end of the passenger boarding bridge, capturing image data relating to a portion of a lateral surface of the aircraft, the doorway being defined within said lateral surface; using an image processor in communication with the imager, retrieving template data relating to the base plate of the doorway of the identified type and sub-type of the aircraft; scaling the retrieved template data based on the sensed current orientation of the one end of the passenger boarding bridge; determining an instruction for moving the one end of the passenger boarding bridge toward the doorway of the aircraft, based on a comparison of the captured image data to the scaled template data; and, automatically performing the instruction so as to move the one end of the passenger boarding bridge toward the doorway of the aircraft.

10. A method according to claim 9, wherein the imager is a digital camera and wherein capturing image data comprises providing a signal relating to the captured image data from the digital camera to the image processor.

11. A method according to claim 9, wherein the template data comprises a plurality of template images of the doorway base plate of the identified type and sub-type of the aircraft.

12. A method according to claim 11, wherein some of the plurality of template images include features of a paint pattern proximate the doorway of the aircraft.

13. A method according to claim 9, wherein sensing the current orientation comprises sensing a distance from the imager to the aircraft.

14. A method according to claim 9, wherein sensing the current orientation comprises sensing tilt of the one end relative to a horizontal reference plane.

15. A method for aligning one end of a passenger boarding bridge with a doorway of an aircraft, comprising: sensing a location of a base plate of the doorway of the aircraft using a sensor that is disposed proximate the one end of the passenger boarding bridge; determining a current location of the one end of the passenger boarding bridge relative to the sensed location of the base plate; and, moving the one end of the passenger boarding bridge from the current location toward the doorway of the aircraft, based upon a known relationship between the location of the doorway and the sensed location of the base plate.

16. A method according to claim 15, wherein the sensor comprises a digital camera and wherein sensing a location of the base plate comprises capturing a digital image of the base plate of the doorway.

17. A method according to claim 16, wherein determining a current location of the one end of the passenger boarding bridge relative to the sensed location of the base plate comprises comparing the captured digital image with stored template data.

18. A method according to claim 17, wherein the stored template data comprises a plurality of template images of the doorway base plate.

19. A method according to claim 18, wherein some of the plurality of template images include features of a paint pattern proximate the doorway of the aircraft.

20. A method according to claim 17, comprising scaling the stored template data based on a sensed orientation of the one end relative to the aircraft.

21. A system for aligning one end of a passenger boarding bridge with a doorway of an aircraft, the aircraft being parked adjacent to the one end of the passenger boarding bridge during a current alignment operation, the system comprising: an imager disposed proximate the one end of the passenger boarding bridge for capturing image data relating to a doorway base plate of the aircraft; a memory element having template image data stored therein, the template image data relating to the doorway base plate of the aircraft; and a processor in communication with the imager and with the memory element, for comparing the captured image data with the template image data and for determining an instruction for moving the one end of the passenger boarding bridge along a direction toward the doorway of the aircraft, based on a result of the comparison.

22. A system according to claim 21, wherein the imager is a digital camera.

23. A system according to claim 22, comprising a light source for illuminating the doorway base plate of the aircraft during image capture by the digital camera.

24. A system according to claim 21, comprising an orientation sensing element for sensing an orientation of the one end of the passenger boarding bridge.

25. A system according to claim 24, wherein the orientation sensing element is an inclinometer in communication with the processor for sensing an orientation of the one end of the passenger boarding bridge relative to a horizontal reference plane.

26. A system according to claim 24, wherein the orientation sensing element is a laser range finder for sensing a distance from the imager to the aircraft.