Patent Description:
The boarding bridge used as an important ground equipment for docking with an aircraft is currently manually docked and withdrawn. However, the operator of the boarding bridge has been defined as an operator for a special work category, i.e., a new operator needs to experience a systematic training for about <NUM> months and then would be approved for operation through a trial examination for more than half a year, and accumulated experiences shall be gained through a continuous learning process with a skilled operator so that a higher technical level can be achieved, in such case, the shortage of boarding bridge operators become a more prominent problem; meanwhile, due to the influence of factors such as leaving and transferring of operators, the running of the aircraft boarding bridge equipment for the airport becomes even more difficult.

In addition, the of operation of the boarding bridge professionally difficult. Each time when docking with the aircrafts, the operator has to pay carefully and cautiously attention to the operation even though the operator has been strictly trained and fully practiced, which may cause self-evident working pressure. Often, in actual work. In the real working situation, operators can be frequently influenced by environment or emergencies, and missing or wrongly performing the relevant operation steps may occur, resulting in accidents like the collision between the boarding bridge and the aircraft or even damage of the aircraft. In addition, erroneous or improper operation may put other personnel and equipment on the airport apron in jeopardize.

With the development and progress of technology, the intelligent level of docking the boarding bridge with the aircraft needs to be improved, the influence of human factors needs to be reduced, and the docking efficiency needs to be improved.

<CIT> discloses a system for aligning an aircraft-engaging end of a passenger boarding bridge to a doorway along a lateral surface of an aircraft, which includes a receiver that is located aboard the aircraft for receiving a signal, including image data for being displayed to a user aboard the aircraft. The system further includes a display device located aboard the aircraft and in communication with the receiver, the display device for receiving the image data from the receiver and for displaying the image data in a human intelligible form to the user aboard the aircraft. A user interface is also located aboard the aircraft for receiving an input signal from the user, which is indicative of one of a go command and a no-go command for automatically aligning the passenger boarding bridge, and for providing data relating to the input signal. Additionally, a transmitter is located aboard the aircraft and in communication with the user interface, the transmitter for receiving the data relating to the input signal and for transmitting a second signal including the data relating to the input signal. During use, the image data relates to features along a lateral surface of the aircraft, the lateral surface including the doorway to which the passenger boarding bridge is to be aligned.

<CIT> describes a system and an assistance method for an operator in the coupling of a boarding bridge to an aircraft. Artificial vision techniques are used and control several parameters provided by sensors and cameras during the execution of the maneuver. Additionally, certain variables are defined to be personally supervised by the operator for safety.

<CIT> concerns telerobotic control apparatus for aligning the movable end of a motorized passenger loading bridge to the door in a vehicle enabling the loading and unloading of passengers and freight. The apparatus includes an improvement display and control system. The apparatus includes: sensors, a display, a set of operator command input devices, and a computer to implement the whole system. The display includes video from a camera, a graphic representation of the relative position of the passenger loading bridge, and text and graphic information on the system status. The control system accepts commands from the operator in the operator's frame of reference and converts them to the passenger loading bridge's frame of reference for moving the passenger loading bridge.

<CIT> relates to a system for aligning an aircraft-engaging end of a passenger boarding bridge to a doorway along a lateral surface of an aircraft, which includes an imager disposed at a location that is remote from the aircraft for capturing an image of a portion of the lateral surface of the aircraft and for providing image data relating to the captured image. A receiver is located aboard the aircraft for receiving a signal including the image data relating to the captured image. In addition, a display device is also located aboard the aircraft and in communication with the receiver, the display device for receiving the image data from the receiver and for displaying to a user aboard the aircraft the image data in a human intelligible form. A user interface located aboard the aircraft is provided for receiving, from the user, an input signal including an indication of a location of the doorway relative to the displayed image data, and for providing data relating to the input signal. A processor is also provided for determining a location of the doorway in dependence upon the data relating to the input signal and the image data, and for providing a control signal relating to the determined location of the doorway.

<CIT> discloses, in a method for aligning an aircraft-engaging end of a passenger boarding bridge with a doorway of an aircraft, a first sensor disposed aboard the aircraft which is used for sensing first information relating to a current bridge alignment operation and a second sensor disposed at a location that is remote from the aircraft which is used for sensing second information relating to the current bridge alignment operation. The sensed first information and the sensed second information are received at a processor. The processor subsequently determines instruction data for moving the aircraft-engaging end of the passenger boarding bridge along a direction toward the doorway of the aircraft, based upon the sensed first information and the sensed second information.

<CIT> provides a passenger boarding bridge that is capable of docking a cab with an aircraft while making it possible to eliminate or simplify operations performed by an operator. The passenger boarding bridge according to one example includes: a tunnel unit; a cab; a drive wheel provided on the tunnel unit or the cab; a rotational mechanism configured to rotate the cab; a controller configured to control the drive wheel and the rotational mechanism; an entrance image capturing camera mounted to the cab and configured to capture an image of an entrance of an aircraft; and an entrance position calculator configured to detect the entrance of the aircraft based on the image of the entrance, which is captured by the entrance image capturing camera, and calculate horizontal positional information of the entrance. The controller is, when the cab is at a predetermined standby position from which the cab starts moving at a time of performing docking of the cab with the entrance, configured to: calculate a target position based on the horizontal positional information of the entrance, which is calculated by the entrance position calculator, the target position being a destination position to which the cab is moved for docking the cab with the entrance; and move the cab from the standby position to the target position.

<CIT> provides an automatic abutting system for a boarding bridge. The system at least comprises a plane berth guiding unit, a boarding bridge operation control unit and a boarding bridge automatic butt joint unit. The plane berth guiding unit is used for guiding a plane to stop on an appointed position and collecting plane stopping basic information. The boarding bridge operation control unit is used for receiving the plane stopping basic information transmitted by the plane berth guiding unit and analyzing and calculating driving lines of the boarding bridge. The boarding bridge automatic butt joint unit is used for making the boarding bridge automatically drive to an appointed plane cabin door position according to the driving lines calculated by the boarding bridge operation control unit so that automatic butt joint can be achieved. According to the automatic abutting system for the boarding bridge, the automatic butt joint of the boarding bridge and the planes of different types can be completely achieved, and labor cost of an airport and potential safety hazards of manual operation are reduced.

<CIT> discloses a vision system for use with an automated control system of a passenger boarding bridge which includes an inclinometer for determining tilt data relating to deviation of the aircraft-engaging end of the passenger boarding bridge relative a horizontal reference plane. The system also includes an imager disposed near the aircraft-engaging end of the passenger boarding bridge, for capturing image data relating to a portion of the aircraft proximate an expected stopping location of the doorway. A memory element having template image data stored retrievably therein is also provided. The template image data relates to at least a template image including a feature that is indicative of the location of the doorway of the aircraft. The vision system further includes an image data processor for determining alignment data for use in aligning the aircraft-engaging end of the passenger boarding bridge with the doorway of the aircraft. The alignment data being determined based upon the tilt data, the image data, and the template image data.

A series of concepts in a simplified form are introduced in the present disclosure, which would be further described in detail in the embodiment. The content of the summary does not attempt to limit the key features and necessary technical features of the claimed technical solution, let alone determine the protection scope of the claimed technical solution.

According to one aspect of the present disclosure, a method for docking a boarding bridge with an aircraft according to claim <NUM> is provided, the method comprising:.

According to one exemplary embodiment of the present disclosure, the acquiring an aircraft image of the aircraft, obtaining a spatial position of the cabin door according to the acquired aircraft image, moving the boarding bridge according to the spatial position to enable the bridgehead to dock with the cabin door includes:.

According to one exemplary embodiment of the present disclosure, the acquiring the aircraft image in real time when the bridgehead is moving from a position where a distance between the bridgehead and the pre-docking position is less than <NUM> meters to a position where the bridgehead is docked with the cabin door, and updating a spatial position of the cabin door in real time according to the aircraft image includes :.

According to one exemplary embodiment of the present disclosure, the obtaining a spatial position of a cabin door sill according to features of a bottom of the cabin door and the region of interest of the cabin door includes :.

According to one exemplary embodiment of the present disclosure, the identifying a frame of the cabin door in the region of interest of the cabin door according to the features of the bottom of the cabin door includes:.

According to one exemplary embodiment of the present disclosure, the method further includes:.

According to one exemplary embodiment of the present disclosure, the method further includes, after matching the bottom model of the cabin door, a step of:
calculating a matching degree between the bottom model of the cabin door and the newly acquired bottom region of interest, and in case that the matching degree is smaller than a preset threshold value, reestablishing the bottom model of the cabin door according to the newly acquired bottom region of interest.

According to one exemplary embodiment of the present disclosure, the step of identifying a region of interest of the cabin door in the aircraft image according to the features of the cabin door includes:.

According to one exemplary embodiment of the present disclosure, a first inflection point is added to the path when the path is adjusted, and
the first inflection point is located in front of the engine closest to the cabin door and at least <NUM> meters away from the closest engine and the wing on which the closest engine is installed.

According to one exemplary embodiment of the present disclosure, a second inflection point is added to the path when the path is adjusted, and
the second inflection point is located in front of the engine which is on the same side of the cabin door but furthest from the cabin door, and the second inflection point is at least <NUM> meters away from the engine.

According to one exemplary embodiment of the present disclosure, a third inflection point is added to the path when the path is adjusted, and
the third inflection point is located in front of a tail end of the wing and at least <NUM> meters away from the wing.

According to one exemplary embodiment of the present disclosure, the anti-collision line of the wing comprises a first line segment extending from the front of the tail end of the wing to the front of the engine closest to the cabin door, and a second line segment extending from an end of the first line segment adjacent to the cabin door to a side of the cabin door facing away from an aircraft nose.

According to one exemplary embodiment of the present disclosure, the method further includes: establishing a first coordinate system fixed relative to the ground and a second coordinate system fixed relative to the aircraft;.

According to one exemplary embodiment of the present disclosure, the identification feature points of the ground identification are intersection points where centerlines of two parking lines respectively intersect with a centerline of a guide line.

According to one exemplary embodiment of the present disclosure, the first coordinate system and the second coordinate system are both rectangular coordinate systems;
where the Z-axis of the first coordinate system is vertical to the ground, and an origin of the first coordinate system is on the ground; an origin of the second coordinate system is at one of the identification feature points, the x-axis of the second coordinate system is vertical to the guide line, the y-axis is parallel to the guide line, and the z-axis is vertical to the ground.

According to another aspect of the present disclosure, a computer-readable storage medium is provided, on which computer programs are stored, wherein the computer programs, when executed by the processor of electronic equipment according to the present disclosure, implement the method as described above.

According to another aspect of the present disclosure, an electronic equipment for docking a passenger boarding bridge to an aircraft is provided, which includes: a plurality of cameras for acquiring an aircraft image of an aircraft.

According to the technical solution, the method for docking the boarding bridge with the aircraft has the advantages and positive effects as follows:
The cabin port can be quickly moved to a position near the cabin door automatically by tracking the path, and the cabin door is positioned by the visual positioning system after being close to the cabin door, so that the accurate spatial position of the cabin door can be obtained, and the cabin port can be accurately docked with the cabin door.

The various objects, features and advantages of the present disclosure will become more apparent through considering the following detailed description of the preferred embodiments of the present disclosure in conjunction with the accompanying drawings. The accompanying drawings are only exemplary illustrate of the present disclosure and are not necessarily to scale. In the accompanying drawings, the same reference numerals generally refer to the same or similar components. In the accompanying drawings:.

Example embodiments will now be described more comprehensive with reference to the accompanying drawings. However, the example embodiments can be implemented via various manners, and should not be understood as being limited to the embodiments set forth herein. Conversely these embodiments are provided so that this disclosure will be comprehensive and complete, and the concepts of the example embodiments will be comprehensively communicated to those skilled in the art. The same reference numerals in the accompanying drawings denote the same or similar structures, and thereby their detailed descriptions will be omitted.

Referring to <FIG>, a boarding bridge <NUM> includes a rotunda column, a rotunda <NUM>, a telescoping tunnel <NUM>, a bridgehead <NUM>, an elevating mechanism, a walking mechanism, a plurality of cameras, and a control unit. The rotunda <NUM> may be installed on a terminal building, or may also be installed on a gallery communicating with the terminal building. The rotunda column is disposed at the bottom of the rotunda <NUM> for supporting the rotunda <NUM>. The telescoping tunnel <NUM> is a stretchable passage, and the telescoping tunnel <NUM> is generally in a shape of a straight bar. One end of the telescoping tunnel <NUM> is installed on the rotunda <NUM>, and the telescoping tunnel <NUM> is rotatably connected with the terminal building through the rotunda <NUM>. A bridgehead <NUM> is installed on the other end of the telescoping tunnel <NUM>. The bridgehead <NUM> may rotate relative to the telescoping tunnel <NUM>. The walking mechanism is disposed below the telescoping tunnel <NUM>, the elevating mechanism is arranged between the walking mechanism and the telescoping tunnel <NUM>, and two ends of the elevating mechanism are respectively connected with the walking mechanism and the telescoping tunnel <NUM>. The telescoping tunnel <NUM> is supported by the elevating mechanism, and the elevating mechanism can drive the telescoping tunnel <NUM> to swing up and down so as to raise or lower the bridgehead <NUM>. The elevating mechanism may be a hydraulic elevating table. The walking mechanism is provided with wheels and a power device for driving the wheels to roll. The walking mechanism can walk on the ground to drive the telescoping tunnel <NUM> to stretch out and draw back in the horizontal direction, so as to drive the bridgehead <NUM> to move in the horizontal direction. The plurality of cameras may be installed on the bridgehead <NUM>, and spaced apart from one another. The control unit is used to control the operation of the boarding bridge <NUM>. The control unit may be a programmable logic controller, and may also be a computer.

Referring to <FIG> shows a method for docking a boarding bridge with an aircraft. The boarding bridge may be automatically controlled by adopting this method to realize automatic docking with the aircraft. The method includes the following steps:.

After the bridgehead reaches the position where a distance between the bridgehead and the pre-docking position is less than <NUM> meters, the aircraft image(s) may be collected in a direction towards the cabin door of the aircraft via the plurality of cameras. After collecting the aircraft image(s), the accurate spatial position of the cabin door can be acquired by analyzing the aircraft image(s). The boarding bridge is controlled to move so that the bridgehead moves towards the cabin door until the bridgehead is docked with the cabin door of the aircraft.

Therefore, the bridgehead may be quickly moved to the position near the cabin door by tracking the path, and the cabin door is positioned by the visual positioning system after the bridgehead being close to the cabin door, so that the accurate spatial position of the cabin door can be acquired, and thus the bridgehead can be accurately docked with the cabin door.

Referring to <FIG>, step S1 includes steps S100 to S160.

Step S100: establishing a first coordinate system which is fixed relative to the ground and a second coordinate system which is fixed relative to the aircraft, and respectively obtaining ground identification parameters in the first coordinate system and the second coordinate system.

Where, coordinates of positions of a ground identification <NUM> and the bridgehead in the first coordinate system are known, and coordinates of the ground identification <NUM>, the cabin door and anti-collision feature points in the second coordinate system are known. Referring to <FIG>, a ground identification <NUM> is provided on the ground of the airport apron. The ground identification <NUM> is used to guide the aircraft <NUM> to dock at a predetermined parking position. The ground identification <NUM> may be a pattern formed by a plurality of parking lines <NUM> intersecting with a guide line <NUM>, and each of the parking lines <NUM> is perpendicular to the guide line <NUM>. The guide line <NUM> is used to guide the aircraft <NUM> to drive on the airport apron along a predetermined route. The parking lines <NUM> are used to indicate a docking position of the aircraft <NUM>. The nose wheel <NUM> of the aircraft <NUM> is located at the intersection of the designated parking line <NUM> and the guide line <NUM>, moreover, when the longitudinal axis of the aircraft <NUM> is approximately parallel to the guide line <NUM>, the aircraft <NUM> is docked at a predetermined parking position, when the accuracy deviation range of the parking position is within an allowable error range of the airport, the aircraft parking position is qualified. The allowable error range is: a deviation absolute value of the axis centerline of the nose wheel <NUM> and the centerline of the parking line <NUM> is less than <NUM> meters, the deviation absolute value of the axis midpoint of the nose wheel <NUM> and the centerline of the aircraft guide line <NUM> is less than <NUM> meters, and the angle between the longitudinal axis of the aircraft <NUM> and the centerline of the guide line <NUM> of the aircraft is less than <NUM> degrees.

The first coordinate system or the second coordinate system may be a rectangular coordinate system or a spherical coordinate system. In this embodiment, both the first coordinate system and the second coordinate system are rectangular coordinate systems.

The first coordinate system includes an X-axis, a Y-axis, and a Z-axis, wherein the X-axis and the Y-axis may be parallel to the ground and the Z-axis may be perpendicular to the ground with a positive direction facing upward. The Z-axis may be coaxial with the axis of the rotunda <NUM>. The origin may be provided on the ground.

After the first coordinate system is established, the ground identification parameters of the ground identification <NUM> in the first coordinate system can be obtained through a method of direct measurement. In this embodiment, the ground identification <NUM> is characterized by two identification feature points. The two identification feature points are a first identification feature point <NUM> and a second identification feature point <NUM> respectively, the first identification feature point <NUM> is an intersection of the centerline of the first parking line <NUM> and the centerline of the guide line <NUM>, and the second identification feature point <NUM> is an intersection of the centerline of the last parking line <NUM> and the centerline of the guide line <NUM>. The ground identification parameters include coordinates of the first identification feature point <NUM> and the second identification feature point <NUM> in a first coordinate system.

The ground identification parameters further include coordinates of a first identification feature point <NUM> and a second identification feature point <NUM> in the second coordinate system. The second coordinate system includes an x-axis, a y-axis, and a z-axis. Both the x-axis and the y-axis are parallel to the ground. The z-axis is perpendicular to the ground and the positive direction thereof is perpendicular to the ground. The x-axis of the second coordinate system may be perpendicular to the guide line <NUM> and the y-axis of the second coordinate system may be parallel to the guide line <NUM>. The origin of the second coordinate system is provided at the first identification feature point <NUM> which is located on the guide line <NUM> and the parking line <NUM>, and the second identification feature point <NUM> passes through the y-axis. The coordinate of the second identification feature point <NUM> can be obtained by measuring a distance between the first identification feature point <NUM> and the second identification feature point <NUM>.

Since the ground identification parameters in the first coordinate system and the second coordinate system are obtained, conditions are provided for coordinate conversion between the first coordinate system and the second coordinate system at any point.

Step S110: obtaining the aircraft model parameters established in the second coordinate system.

The aircraft model is pre-established in the second coordinate system and is represented by coordinates in the second coordinate system. Different types of aircraft models may be built for different types of aircraft <NUM>. When establishing the aircraft model, the ground identification <NUM> is used as a reference to obtain the model parameters for simulating the aircraft when the aircraft <NUM> is parked at a predetermined parking position. In this way, the relative positional relationship between the ground identification <NUM> and the aircraft model is determined.

Referring to <FIG> and <FIG>, the aircraft model parameters include the coordinates of a cabin door feature point <NUM> and a plurality of anti-collision feature points <NUM>, <NUM>, <NUM> in the second coordinate system. The cabin door feature point <NUM> is used to characterize the position of the cabin door <NUM>. The cabin door feature point <NUM> may be a point on the cabin door <NUM> or near the cabin door <NUM>. In this embodiment, the feature of the cabin door point <NUM> is <NUM> below the door seam at a side of a rotating shaft of the cabin door <NUM>.

Acquiring a preset anti-collision line <NUM> of the wing <NUM>. The process of acquiring the anti-collision line <NUM> of the wing <NUM> includes: calculating coordinates of the anti-collision feature points <NUM>, <NUM>, <NUM> in the first coordinate system according to the coordinates of the ground identification <NUM> in the first coordinate system and the second coordinate system and coordinates of the anti-collision feature points <NUM>, <NUM>, <NUM> in the second coordinate system, and connecting the anti-collision feature points <NUM>, <NUM>, <NUM> so that the anti-collision line of the wing <NUM> is acquired. The anti-collision line <NUM> of the wing <NUM> is a virtual line provided between the wing <NUM> of the aircraft <NUM> and the boarding bridge <NUM>. The anti-collision line <NUM> of the wing <NUM> is a line preset in the system, and the anti-collision line <NUM> of the wing <NUM> matching the outline of the wing <NUM> may be provided according to different aircraft types. The anti-collision line <NUM> of the wing <NUM> is used to limit the boarding bridge <NUM> in order to avoid collision of the boarding bridge <NUM> with the wing <NUM>. If the outer contour of boarding bridge <NUM> touches the anti-collision line <NUM> of the wing <NUM>, it indicates that the boarding bridge <NUM> has a risk of colliding with the wing <NUM>.

The plurality of anti-collision feature points <NUM>, <NUM> and <NUM> are connected in sequence through straight lines to obtain the anti-collision line <NUM> of the wing <NUM>. The coordinates of the plurality of anti-collision feature points <NUM>, <NUM>, <NUM> are used to characterize the position and shape of the anti-collision line <NUM> of the wing <NUM>. In this embodiment, the anti-collision line <NUM> of the wing <NUM> includes a first line segment <NUM> and a second line segment <NUM>. The first line segment <NUM> extends from a front position of a tail end of the wing <NUM> to the front of the engine <NUM> closest to the cabin door <NUM>, and the second line segment <NUM> extends from an end of the first line segment <NUM> near the cabin door <NUM> to a side of the cabin door <NUM> away from the aircraft nose. Among them, the first line segment <NUM> is located in front of all of engines <NUM> at the side of the cabin door <NUM>. In this embodiment, there are three anti-collision feature points, i.e., a first anti-collision feature point <NUM> is located in front of the tail end of the wing <NUM>, a second anti-collision feature point <NUM> is located in front of the engine <NUM> closest to the cabin door <NUM>, and a third anti-collision feature point <NUM> is located at a side of the cabin door <NUM> facing away from the aircraft nose, and these three anti-collision feature points are sequentially connected to obtain the anti-collision line <NUM> of the wing <NUM>. The first segment <NUM> and the second segment <NUM> of the anti-collision line <NUM> of the wing <NUM> are preferably both tangential to the outer contour of the engine <NUM>.

Step S120: performing a coordinate transformation on the aircraft model parameters according to the ground identification parameters in the first coordinate system and the second coordinate system to obtain the aircraft model parameters in the first coordinate system.

Since the parameters of the ground identification <NUM> in the first coordinate system and the second coordinate system are obtained in advance, i.e., the coordinate of the first identification feature point <NUM> in the first and second coordinate systems and the coordinate of the second identification feature point <NUM> in the first and second coordinate systems are obtained in advance, and the Z-axis of the first coordinate system and the z-axis of the second coordinate system are parallel to each other, the coordinates of the cabin door feature point <NUM> and the multiple anti-collision feature points <NUM>, <NUM>, and <NUM> in the second coordinate system can be transformed to obtain the coordinates of the cabin door feature point <NUM> and the multiple anti-collision feature points <NUM>, <NUM>, and <NUM> in the first coordinate system. So that the aircraft model parameters are transformed to the first coordinate system.

Step S130: obtaining the bridgehead parameters in the first coordinate system.

The boarding bridge <NUM> is parked in a safety region before docking with the aircraft. The bridgehead parameters may be obtained by measuring the bridgehead <NUM>. The bridgehead parameters include the coordinate of the bridgehead feature point <NUM> in the first coordinate system. The bridgehead feature point <NUM> may be a midpoint of the bumper of the bridgehead <NUM>. The bridgehead feature point <NUM> and the cabin door feature point <NUM> correspond to each other, and the bridgehead <NUM> is aligned with the cabin door <NUM> when the bridgehead feature point <NUM> and the feature of the cabin door <NUM> are closer to each other.

In this way, the bridgehead <NUM> and the aircraft model are unified into the first coordinate system.

Step S140: referring to <FIG>, planning a path <NUM> for the bridgehead <NUM> of the boarding bridge moves from the parking position to the pre-docking position in the first coordinate system according to the bridgehead parameters and the aircraft model parameters in the first coordinate system.

Acquiring a pre-docking position and a position at which the bridgehead is located when the boarding bridge is at the parking position, and generating a path <NUM> for connecting the two positions. The pre-docking position is represented by a pre-docking point <NUM>. When the bridgehead feature point <NUM> reaches the pre-docking point <NUM>, it indicates that the bridgehead <NUM> reaches the pre-docking position. The path <NUM> may be planned according to the shortest path principle. One end of the path <NUM> is connected to the position of the bridgehead feature point <NUM> when the boarding bridge is in the parking position, and the other end of the path <NUM> is connected to the pre-docking point <NUM>. The bridgehead feature point <NUM> travels along this path <NUM> to reach the pre-docking point <NUM>. The process of acquiring the pre-docking position includes: calculating the coordinate of the cabin door <NUM> in the first coordinate system according to coordinates of the ground identification <NUM> in the first coordinate system and the second coordinate system and the coordinate of the cabin door <NUM> in the second coordinate system, and calculating a coordinate of a pre-docking point according to the coordinate of the cabin door <NUM> in the first coordinate system.

The distance between the pre-docking point <NUM> and the cabin door feature point <NUM> is within a range of <NUM>-<NUM> meters, and the distance between the pre-docking point <NUM> and the cabin door feature point <NUM> is preferably <NUM> meters. The connecting line between the pre-docking point <NUM> and the feature of the cabin door point <NUM> is perpendicular to the cabin door.

When the bridgehead <NUM> of the boarding bridge <NUM> is operated to a position where a distance between the bridgehead and the pre-docking point <NUM> is less than <NUM> meters, the boarding bridge <NUM> may switch the visual positioning system to identify the cabin door <NUM> and guide the bridgehead <NUM> of the boarding bridge <NUM> to continuously approach the cabin door <NUM>, so that the alignment of the bridgehead <NUM> and the cabin door <NUM> is more accurate.

Step S150: simulating the process of the boarding bridge <NUM> moving to the pre-docking position along the path <NUM>, and adjusting at least a part of the path <NUM> in front of an engine <NUM> in a direction radially away from the engine <NUM> if interference is formed between the anti-collision line <NUM> of the wing <NUM> and an outer contour of the boarding bridge <NUM> during simulation, and then simulating again until there is no more interference formed between the anti-collision line <NUM> of the wing <NUM> and the outer contour of the boarding bridge <NUM>.

In this way, the finally formed path <NUM> can be used as the path <NUM> along which the boarding bridge <NUM> travels, and the bridgehead <NUM> of the boarding bridge <NUM> can travel along the path <NUM> without collision between the boarding bridge <NUM> and the wing <NUM>.

The step S150 includes steps S151 to S154.

Step S151: establishing an outer contour model of the boarding bridge <NUM> in the first coordinate system.

Step S152: simulating the process of the bridgehead <NUM> moving to the cabin door <NUM> along the path <NUM>, and judging whether the outer contour model of the boarding bridge <NUM> and the anti-collision line <NUM> of the wing <NUM> interfere with each other in this process, specifically, if so, performing the step S153 for adjusting the path <NUM>, or otherwise, performing the step S154;
Step S153: moving a part of the path <NUM> in front of the engine <NUM> in a direction away from the engine <NUM>, and proceeding to step S152.

Since the engine <NUM> protrudes from the front of the wing <NUM>, moving a part of the path <NUM> in front of the engine <NUM> away from the engine <NUM> can further prevent the engine <NUM> and a part of the wing <NUM> near the engine <NUM> from colliding with the boarding bridge <NUM>.

Preferably, a first inflection point <NUM> is added on the path <NUM> while the path <NUM> is being adjusted. The first inflection point <NUM> is located in front of the engine <NUM> closest to the cabin door <NUM> and at least <NUM> meters away from the engine <NUM>. The path <NUM> at this moment is a line connected in sequence by the bridgehead feature point <NUM> when the boarding bridge is at the parking position, the first inflection point <NUM> and the pre-docking point <NUM>.

After the first inflection point <NUM> is added, the distance between the outer contour of the boarding bridge <NUM> and the engine <NUM> closest to the cabin door <NUM> increases when the boarding bridge <NUM> moves, and the outer contour of the boarding bridge <NUM> can be effectively prevented from colliding with the engine <NUM>. The first inflection point <NUM> is more preferably located in front of the side of the engine <NUM> near the cabin door <NUM> side.

More preferably, the second inflection point <NUM> is added on the path <NUM> when the path <NUM> is adjusted. The second inflection point <NUM> is located in front of the engine <NUM> which is on the same side of the cabin door <NUM> but furthest from the cabin door <NUM>, and the second inflection point <NUM> is at least <NUM> meters away from this engine <NUM>. The path <NUM> at this time is a line connected in sequence by the bridgehead feature point <NUM> when the boarding bridge is at the parking position, the second inflection point <NUM>, the first inflection point <NUM>, and the pre-docking point <NUM>.

After the second inflection point <NUM> is added, since the first inflection point <NUM> and the second inflection point <NUM> are respectively located in front of two engines <NUM>, and one of the two engines <NUM> is close to the cabin door <NUM> and the other is away from the cabin door <NUM>. The distance between the outer contour of the boarding bridge <NUM> and all the engines <NUM> is increased when the boarding bridge <NUM> moves, and thus the outer contour of the boarding bridge <NUM> can be effectively prevented from colliding with all the engines <NUM>. The second inflection point <NUM> is preferably located in front of the side of the engine <NUM> away from the cabin door <NUM>.

Preferably, a third inflection point <NUM> is added on the path <NUM> when the path <NUM> is adjusted. The third inflection point <NUM> is located in front of the tail end of the wing <NUM> and at least <NUM> meters away from the wing <NUM>. The path <NUM> at this time is a line connected in sequence by the bridgehead feature point <NUM> when the boarding bridge is at the parking position, the third inflection point <NUM>, the second inflection point <NUM>, the first inflection point <NUM>, and the pre-docking point <NUM>.

After the third inflection point <NUM> is added, the third inflection points <NUM> are respectively located at least <NUM> meters in front of the tail end of the wing <NUM>. the distance between the outer contour of the boarding bridge and the tail end of the wing <NUM> is increased when the boarding bridge <NUM> moves, and the outer contour of the boarding bridge <NUM> can be effectively prevented from colliding with the tail end of the wing <NUM>.

Preferably, a pre-parking point <NUM> is also provided on the path <NUM>. It is usually necessary to delimit a safety zone for the boarding bridge. The boarding bridge can move in the safety zone without causing interference to the operation of the aircraft <NUM> or other equipment. The pre-parking point <NUM> is disposed at the edge of the safety zone and near the parking position of the aircraft <NUM>. The path <NUM> at this time is a line connected in sequence by the bridgehead feature point <NUM> when the boarding bridge is at the parking position, the pre-parking point <NUM>, the third inflection point <NUM>, the second inflection point <NUM>, the first inflection point <NUM> and the pre-docking point <NUM>.

The bridgehead <NUM> of the boarding bridge <NUM> may reach the pre-parking point <NUM> from a starting point of the path <NUM> in advance before the aircraft <NUM> arrives at its parking position, and the boarding bridge <NUM> starts from the pre-parking point <NUM> after the aircraft <NUM> arrives at its parking position can achieve docking with the aircraft faster, thus improve the docking efficiency.

Step S160: driving the boarding bridge <NUM> so that the bridgehead <NUM> is moved to a position where a distance between the bridgehead and the pre-docking position is less than <NUM> meters along the path <NUM>.

In this step, the walking mechanism and the elevating mechanism of the boarding bridge <NUM> cooperate with each other to move the bridgehead <NUM> so that the bridgehead feature point <NUM> on the bridgehead <NUM> can move along the path <NUM>.

The minimum distance between the outer contour of the boarding bridge <NUM> and the anti-collision line <NUM> of the wing <NUM> is calculated in real time in the moving process of the boarding bridge <NUM>, and if the minimum distance is smaller than a first preset value and larger than a second preset value, the moving speed of the boarding bridge is reduced, for example, the moving speed of the boarding bridge is reduced to <NUM>% of the maximum speed of the boarding bridge. The second preset value is smaller than the first preset value, a value range of the second preset value may be from <NUM> to <NUM>, and a value range of the first preset value may be from <NUM> to <NUM>. If the minimum distance between the outer contour of the boarding bridge <NUM> and the anti-collision line <NUM> of the wing <NUM> is below the second preset value, the boarding bridge stops moving and sends an alarm.

Further, referring to <FIG>, the step S2 includes steps S21 and S22.

Step S21: acquiring the aircraft image in real time in a process of the bridgehead moving from a position where a distance between the bridgehead and the pre-docking position is less than <NUM> meters to a position where the bridgehead can be docked with the cabin door, and updating a spatial position of the cabin door in real time according to the acquired aircraft image.

Step S22: moving the boarding bridge with the newly acquired spatial position of the cabin door as a docking destination of the bridgehead until the bridgehead is docked with the cabin door.

When the bridgehead reaches the position where the distance between the bridgehead and the pre-docking position is less than <NUM> meters, aircraft images are collected in real time through the plurality of cameras, at this time, the distance between the bridgehead and the cabin door is less than <NUM> meters, and the aircraft images contain clear cabin door patterns when the plurality of cameras take pictures of the aircraft. The aircraft image is analyzed to obtain the spatial position of the cabin door, and the spatial position of the cabin door can be obtained in real time by collecting and analyzing the aircraft image in real time in the process that the bridgehead moves to dock with the cabin door from the pre-docking position. When the spatial position obtained in real time acts as the docking destination of the bridgehead, the more accurate spatial position of the cabin door can be continuously obtained in the process that the bridgehead moves to dock with the cabin door from the pre-docking position, and posture and movement direction of the boarding bridge are adjusted according to the spatial position, so that the docking can be more accurate.

Further, referring to <FIG>, the step S21 includes:.

The region of interest of the cabin door in the aircraft image is identified according to the features of the cabin door, and a cabin door frame in the aircraft image is identified according to the features of the bottom of the cabin door in the region of interest of the cabin door. The spatial position of the cabin door sill can be calculated according to the position of the cabin door sill in the aircraft image and the spatial position of the camera for collecting the aircraft image. Identification of the cabin door is achieved via the machine vision, thereby avoiding the problem of poor universality caused by the fact that special mark needs to be provided on an aircraft when the cabin door is identified. The accurate positioning of the cabin door facilitates fully automatic docking of the boarding bridge with the aircraft.

In step S211, an aircraft image is acquired.

Where, the target aircraft image may be acquired via an imaging system, which may include imaging instruments, such as a plurality of cameras and light sources, and image acquisition devices, such as image acquisition cards, and the like. The imaging system may rapidly and stably collect images within a designated region in a designated application scene, for example, an image at a side of an aircraft in which the cabin door is installed can be obtained. When the aircraft image is obtained, the image at the side of the aircraft in which the cabin door is installed can be continuously and dynamically captured, for example, by making a video for the image at the side of the aircraft in which the cabin door is installed, and optionally, the image at a side of the aircraft in which the cabin door is installed may be discretely and dynamically obtained, for example, the aircraft image is taken once at designated intervals, the embodiments of the present disclosure do not specifically limit this.

In step S212, a region of interest of the cabin door in the aircraft image may be identified according to the features of the cabin door.

The features of the cabin door may be dimensions of the cabin door, such as a shape, a length, a height, and the like of the cabin door. The data of the features of the cabin door is preset data. The region of interest of the cabin door may be a region in the image that matches with the region of the cabin door, which may be a region of the cabin door in the image, or a region in the image that is within the tolerance of the error.

Further, referring to <FIG>, the step S212 includes steps S2121 to S2124:
Step S2121: performing edge detection on the aircraft image to obtain a plurality of edge lines.

The imaging system is usually installed on the boarding bridge, and moves together with the boarding bridge, when the identification is started, the boarding bridge is far away from a target aircraft, and the target aircraft image acquired by the imaging system includes the whole region of the cabin door. The cabin doors are typically provided with different coatings to form the cabin door profile and a stainless steel sill is provided at the bottom of the cabin door, there is a door seam between the cabin door and the aircraft fuselage, and edges of the above features form lines with specific dimensions in the image.

Based on the above features, edge detection may be performed on the target aircraft image, for example, the edge detection is performed on the aircraft image by using methods such as a canny operator or a Sobel operator, and a plurality of lines including edge lines of the cabin door shown in <FIG> are obtained by edge detection and binarization.

In step S2122, extracting vertical lines extending in the vertical direction are from the plurality of edge lines, and calculating spatial positions of two endpoints of each vertical line.

In practical applications, the plurality of lines obtained in step S2121 includes cabin door lines and other interference lines, and thus excessive lines are not favorable for analysis. Thus, the vertical lines extending in the vertical direction may be extracted for convenience of analysis. Referring to <FIG>, generally included in the aircraft image are mainly horizontal lines and vertical lines, and thus extracting the vertical lines may be implemented by filtering out the horizontal lines. The filtering of the horizontal lines can be realized by using a Sobel operator, and certainly, the method for extracting the vertical lines in practical application may also be other methods, which is not limited in the embodiments of the present disclosure.

The spatial positions of the two endpoints of each vertical line may be calculated by a multi-view visual triangulation calculation method. A third coordinate system which is relatively fixed with the bridgehead is established, and coordinates of the two endpoints of the vertical line in the third coordinate system are calculated.

Step S2123: calculating a length of each vertical line and a spacing between every two vertical lines according to the spatial positions of the two endpoints of each vertical line;
When the spatial positions of two endpoints of each vertical line are known, the length of each vertical line may be calculated by calculating the spacing between these two endpoints, and certainly, in order to improve the calculation efficiency, the length of each vertical line may be estimated roughly by a priori knowledge without accurately calculating the spatial positions of the two endpoints. Meanwhile, since the vertical lines are parallel to each other, the spacing between every two vertical lines may be calculated according to the spatial positions of the endpoints.

Step S2124: delimiting a region between two vertical lines in the aircraft image as a region of interest of the cabin door when lengths of two of the plurality of vertical lines are matched with a length of the cabin door, and the spacing between the two vertical lines is matched with a width of the cabin door.

The length of the cabin door in the vertical direction is compared with the lengths of the plurality of vertical lines, and the width of the cabin door in the horizontal direction is compared with the spacing between any two of the plurality of vertical lines;
The region between two vertical lines in the aircraft image is delimited as a region of interest of the cabin door when lengths of two of the plurality of vertical lines are matched with a length of the cabin door in the vertical direction, the spacing between the two vertical lines is matched with a width of the cabin door in the horizontal direction, and a ratio of the lengths of the two vertical lines to the spacing between the two vertical lines is matched with a ratio of the length to the width of the cabin door. The length matching means that the lengths are the same or the length difference is within a threshold range, for example, the spacing deviation is less than <NUM>, and the height deviation is less than <NUM>.

Step S213: obtaining the spatial position of the cabin door sill according to the features of the bottom of the cabin door and the region of interest of the cabin door. The step S213 includes steps S2131 to S2132.

Step S2131: identifying a frame of the cabin door in the region of interest of the cabin door according to the features of the bottom of the cabin door;
The bottom of the cabin door has more features including cabin door coating marks, door seams with corners, stainless steel sills and the like, and the features may be identified within the region of interest of the cabin door in the aircraft image, so that the position of the frame of the cabin door in the aircraft image can be determined.

The step S2131 includes steps S2131a to S2131c,.

In step S213 1a, the cabin door sill may be identified in the region of interest of the cabin door by edge detection. Before the edge detection, part of the noise and some small unnecessary details can be eliminated in the region of interest of the cabin door by the mean-shift filter algorithm of open-cv, and then edge detection is performed by canny operator. The edge detection may obtain a plurality of regions, for example, a plurality of enclosed regions as shown in <FIG>, and the plurality of enclosed regions may be filled with colors during the detection process, so as to distinguish the regions. Of course, the edge may also be detected by other edge detection operators, and the embodiments of the present disclosure are not limited thereto.

The lowest region is selected from the detected enclosed regions, where, the region is in the region of interest of the cabin door and meets certain size requirements, for example, the width of the enclosed region is not less than <NUM> pixels. At this time, the enclosed region is a sill region, the upper edge of the enclosed region is the lower door seam line, the center point of the upper edge is marked as an identification point, and the upper, the lower, the horizontal, the vertical, the upper edge, the lower edge and the like in the embodiment of the present disclosure refer to orientations of the aircraft in a state of parking at the airport.

In step S2131b, the door seam lines are searched in the image at both sides of the identification point.

During the door seam search, searching along a line with the highest contrast at two sides of the identification point on the upper edge of the sill region of the cabin door, calculating the maximum contrast difference of each point on the edge obtained by edge detection, and selecting the point with the contrast and the direction conforming to the features of the door seam.

In the process of searching the door seam, a sequence of traversing points of the region to be searched may be determined according to an extending direction of the simulated quadratic Bezier curve. The quadratic Bezier curve may be described by using two parameters, i.e., a direction "forward" and an offset "side", wherein thresholds of "forward" and "side" may be selected according to actual conditions in actual application.

For example, forward ∈ [<NUM>, <NUM>], side ∈ [<NUM>, <NUM>], the expression of the quadratic Bezier curve is as follows: <MAT>
wherein t is a parameter of the quadratic Bezier curve, t ∈ (<NUM>, <NUM>), po is a detection point D0, another detection point D2 is po + forward + side, the control point D1 is po + <NUM>side.

As shown in <FIG>, the detected edge line is divided into a plurality of line segments D0 to D2, a quadratic Bezier curve as described above is constructed, and points that match the features of the door seam are searched in the edge lines, the points are selected as points that meet requirements of the door seam.

In step S2131c, an intersection of a horizontal line and a vertical line in the door seam line can be obtained as an endpoint of the cabin door sill.

The door seam shown in <FIG> may be obtained by the step S2131b, the door seam includes horizontal and vertical lines, and an intersection point between the horizontal and the vertical lines can be obtained through a linear fitting manner, and each of two vertical lines has an intersection point with the horizontal line, and two intersection points S1 and S2 act as endpoints of the cabin door sill, and two endpoints may act as identification points for automatic docking of the boarding bridge.

Step S2132: acquiring the spatial position of the frame of the cabin door according to a position of the frame of the cabin door in the aircraft image.

The spatial positions of two endpoints of the cabin door sill of the aircraft may be calculated by a multi-view visual triangulation method, i.e., three-dimensional coordinates of the endpoints in the third coordinate system. The multi-view visual triangulation method is based on parallax, and three-dimensional information may be acquired by a triangulation principle, i.e., a triangle is formed between an image plane of two or more cameras and a measured object. When positions of two or more cameras in the third coordinate system are known, three-dimensional dimensions of the object in the common field of view of the cameras and the three-dimensional coordinate of feature points of the spatial object in the third coordinate system can be obtained. In step S22, when the bridgehead docks with (abuts against) the cabin door, the midpoint of the bumper of the bridgehead is aligned to a position that is <NUM> below the above two endpoints, and the bridgehead can completely cover the region of the aircraft cabin door, i.e., the docking between the bridgehead and the cabin door is completed.

Further, since the docking of the boarding bridge with the aircraft cabin door is a dynamic process, in the process of identifying the aircraft cabin door, dynamical identification can be performed, and the accuracy of identifying the aircraft cabin door can be ensured by continuous correction. The method for identifying the aircraft cabin door may also include the following steps:.

When the bottom model of the cabin door is established, the region near the sill in the images acquired by two cameras in binocular vision can be used for stereo matching, and may be realized by adopting a Stereo SGBM algorithm of open-cv. The bottom model of the cabin door is formed by calculating spatial coordinates of a plurality of points on the sill and the door seam lines, the modeled bottom model of the cabin door is a plane, and the plane includes information of a plurality of known points, such as the coordinates of these known points in the plane, the contrast and the edge direction on the image, and the like. When stereo matching is performed, in the spatial coordinate of the obtained plurality of points, points in the plane of the cabin door are reserved as effective points in the model, and points that are not in the plane of the cabin door are discarded. The bottom model of the cabin door of the aircraft is established by the plurality of effective points. Where, points having a distance less than or equal to the distance threshold from the plane of the cabin door are considered to locate in the plane of the cabin door and points having a distance greater than the distance threshold from the plane of the cabin door are considered to locate outside the plane of the cabin door. For example, the points having a distance less than or equal to <NUM> from the cabin door are retained, and the points having a distance greater than <NUM> from the cabin door are discarded.

Step S215: re-acquiring the aircraft image;
In the dynamic process of the boarding bridge approaching to the cabin door, the target aircraft image is obtained dynamically, for example, each frame of the obtained aircraft image may be identified, i.e., the aircraft image is updated once in each frame. Of course, in practical application, the target aircraft image may also be obtained according to other rules, for example, the target aircraft image is obtained every second or more, which is not specifically limited in the embodiments of the present disclosure.

Step S216: searching a bottom region of interest in the newly acquired aircraft image by matching the bottom model of the cabin door;
Where, the newly acquired aircraft image is the aircraft image which is reacquired in Step S215. Since the aircraft picture is rapidly acquired by frames, and the contents of pictures obtained in two adjacent times in the docking process do not change much, the bottom region of interest in the aircraft picture obtained this time may be searched according to the position of the bottom region of interest in the aircraft picture obtained last time, so that the calculation amount can be greatly reduced, and the speed of obtaining the bottom region of interest at this time is improved. Meanwhile, searching in a way of matching the bottom model of the cabin door can further reduce the calculated amount compared with searching in a way of matching bottom features of the cabin door for the first time. In the updating process, as the relative position of the boarding bridge and the aircraft changes, the size of the aircraft image changes in the obtained image, and the aircraft image can be scaled when the bottom region of interest of the newly obtained aircraft image is acquired. For example, when the aircraft and the boarding bridge are close to each other, the aircraft image can be zoomed out, and when the aircraft and the boarding bridge are away from each other, the aircraft image can be zoomed in. The multiples of zoom out or zoom in may be calculated by the amount of change in the distance between the aircraft and the boarding bridge, for example, calculating based on the relative speed therebetween, and the time interval of image updating, or may be calculated by using an image pyramid to traverse a plurality of magnification or reduction scales, for example, <NUM> to <NUM> times. In addition, a newly obtained aircraft image may be analyzed into a plurality of images with arrangement based on a resolution ranging from small to large, and one image with the highest matching degree with the bottom model of the cabin door can be selected as the current aircraft image by sequentially matching the images with the bottom model of the cabin door.

After the bottom region of interest and the bottom model of the cabin door are obtained for the first time, traverse around the current door region in the image in the next frame to search for the bottom region of interest, if the bottom region of interest is not found, expend the searching range, and reduce the matching degree requirement, and if the bottom region of interest is not found in three continuous frames, report the tracking failure and then end the tracking and positioning task, and after that, the cabin door information may be searched again.

Step S217: updating the spatial position of the cabin door sill of the aircraft according to the bottom region of interest in the newly acquired aircraft image.

In this step, the endpoint of the cabin door sill is searched in the bottom region of interest in the newly acquired aircraft image by using the bottom model of the cabin door generated last time;
The spatial position of the endpoint of the cabin door sill is calculated.

For the same aircraft, the position of the endpoint of the cabin door sill of the aircraft on the aircraft is not changed, i.e., the position thereof on the aircraft image is also not changed, and the endpoint of the cabin door sill may be searched in the bottom region of interest according to the bottom model of the cabin door. After the endpoint of the cabin door sill is searched in the bottom region of interest, the spatial positions of two endpoints of the doorsill are calculated.

The spatial position of the endpoints of the cabin door sill is updated by the bottom model of the cabin door, thereby reducing the calculation amount of updating the spatial position of the endpoints of the cabin door sill in the process that the boarding bridge continuously approaches the aircraft, and improving the response speed.

It should be noted that, during the process of the boarding bridge approaching the cabin door, updating of the target aircraft image and updating of the spatial position of the endpoints of the cabin door sill are continuous, and for example, updating may be performed at intervals of a specified time, such as <NUM> seconds, <NUM> seconds, <NUM> second, <NUM> seconds, <NUM> seconds, <NUM> seconds, and the like.

Step S218: if an identification stopping instruction is received, stopping acquiring of the spatial position of the cabin door, or otherwise, performing the step S215.

Judging whether an identification stopping instruction is received; when the identification stopping instruction is received, stopping identification of the cabin door; and when the identification stopping instruction is not received, updating the aircraft image until the identification stopping instruction is received. Where, the identification stopping instruction is used for controlling to stop identifying the cabin door, for example, after the boarding bridge docking with the cabin door is completed, the identification of the cabin door is stopped through the identification stopping instruction.

In the process of the boarding bridge dynamically approaching the cabin door, the cabin door needs to be tracked and positioned after the bottom model of the cabin door is established, and the bottom position of the cabin door in each frame of image is updated. Since the position of the cabin door in the image changes slowly and continuously in practice, bottom features of the cabin door are searched near the position of the image in the previous frame is not only efficient but also accurate.

Further, the method further includes: a step S219 after the step S216 and before the step S218.

Step S219: calculating a matching degree between the bottom model of the cabin door and the newly acquired bottom region of interest, and if the matching degree is smaller than a preset threshold value, reestablishing the bottom model of the cabin door according to the newly acquired bottom region of interest.

The matching degree of the newly acquired bottom region of interest and the bottom model of the cabin door is compared. When the matching degree of the newly acquired bottom region of interest and the bottom model of the cabin door is smaller than a preset threshold value, the bottom model of the cabin door is updated according to the newly acquired bottom region of interest. For example, if the matching degree is less than <NUM>, a template is relearned and the model is updated.

Further, in order to ensure the sharpness of the aircraft image during the image identification, the method includes a step of performing noise reduction process on the aircraft image before the step S212.

The step of performing noise reduction process on the aircraft image includes: adjusting brightness of the aircraft image; judging whether the aircraft image has noise according to the signal-to-noise ratio of the aircraft image; and filtering out the noise when the aircraft image has noise.

Firstly, as shown in <FIG>, evaluate the brightness of the acquired original aircraft image, and adjust the brightness of the aircraft image to achieve the best brightness. Then, evaluate the imaging environment of the aircraft image, and screen and process the aircraft image with high contrast (such as direct light, reflected light, partial backlight or the like), the aircraft image in rain and snow weather and the aircraft image in haze weather, and finally the high-quality aircraft image is output from the preprocessing module, so that the speed, reliability and precision of the identification and positioning of the cabin door in the subsequent steps are improved.

As shown in <FIG>, the steps of brightness adjustment are as follows: firstly, evaluating whether the brightness of the aircraft image is qualified, if the brightness is too bright, preferably adjusting the brightness of the light source, if the light source is turned off then adjusting (decreasing) the exposure time of the imaging equipment, adjusting according to a certain amount of subdivision each time until the brightness of the aircraft image meets the requirements, and then outputting the aircraft image with the brightness meeting the requirement after adjustment is finished, if the light source is has been turned off and the exposure time has been adjusted to be the shortest, but the brightness of the aircraft image is still too bright, then outputting an over-bright prompt, and finishing the adjustment. If the brightness is too dark, also preferably adjusting the brightness of the light source, and if the light source is adjusted to be brightest, then adjusting (increasing) the exposure time of the imaging equipment, and adjusting each time according to a certain amount of subdivision until the brightness of the aircraft image meets the requirement, outputting the aircraft image with the brightness meeting the requirement after the adjustment is finished, and if the light source is adjusted to be brightest and the exposure time is adjusted to be longest but the brightness of the aircraft image is still too dark, outputting an over-dark prompt, and finishing the adjustment.

After the brightness adjustment is finished, the aircraft image is further processed to improve the adaptability of the system to all-weather operation. Firstly, the contrast of the aircraft image is detected, and the aircraft image is optimized and enhanced to increase the processing capacity of the system for situations of strong shadow, local illumination and the like. The method of contrast detection adopts histogram analysis, histogram equalization processing is performed on the aircraft image with abnormal brightness distribution, the optimized target aircraft is obtained, and the details of portions with highlight and backlight can be well represented. The rain and snow may be regarded as check noise in the aircraft image, whether the aircraft image belongs to the rain and snow may be identified through the signal-to-noise ratio, and then most of noise interference caused by the rain and snow may be filtered out through the media filtering. The influence of fog and haze to the aircraft image can reduce sharpness and the acuteness of the aircraft image, and can be recovered very well by guiding filter.

After preprocessing, the aircraft image is already able to represent the information of the cabin door, and then searching the cabin door. At the beginning, the system does not know the position of the cabin door in the aircraft image, so the door must be identified from the target aircraft image before spatial position detection can be performed. Once the cabin door is detected and confirmed, positioning can only focus on two corners of the bottom of the cabin door with the most abundant feature information and the most critical position information, and continuously track the position of this part of the aircraft image, so that the region for processing the aircraft image is reduced, and the speed and the precision thereof are improved.

It should be noted that although steps of the method of the present disclosure are depicted in the drawings in a particular order, this does not require or imply that the steps must be performed in this particular order or that all of the depicted steps must be performed to achieve desirable results. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step to be performed, and/or one step may be divided into multiple steps to be performed, etc..

In one exemplary embodiment of the present disclosure, an electronic equipment capable of implementing the above method is also provided.

As will be appreciated by those skilled in the art, aspects of the present disclosure may be embodied as a system, a method or a program product. Accordingly, various aspects of the present disclosure may be embodied in the form as follows: an entire hardware implementation, an entire software implementation (including firmware, microcode, etc.), or an implementation combining hardware and software that may generally be referred to as a "circuit", "module" or "system" herein.

An electronic equipment <NUM> according to this embodiment of the present disclosure is described below with reference to <FIG>. The electronic equipment <NUM> shown in <FIG> is only an example and should not limit the function and usage scope of the embodiments of the present disclosure.

As shown in <FIG>, the electronic equipment <NUM> is expressed in the form of a general purpose computing equipment. The components of the electronic equipment <NUM> include a plurality of cameras for acquiring an aircraft image of an aircraft, and may include, but may not be limited to: the at least one processing unit <NUM>, the at least one storage unit <NUM>, and a bus <NUM> connecting different system components (including the storage unit <NUM> and the processing unit <NUM>).

The storage unit stores program codes that may be executed by the processing unit <NUM>, such that the processing unit <NUM> performs the steps according to various exemplary embodiments of the present disclosure described in the above section "exemplary method" of this specification.

The storage unit <NUM> may include readable medium in the form of volatile storage units, such as a random access storage unit (RAM) <NUM> and/or a cache storage unit <NUM>, and may further include a read only storage unit (ROM) <NUM>.

The storage unit <NUM> may also include a program/utility tool <NUM> having a set (at least one) of program modules <NUM>, the program module <NUM> includes, but is not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination thereof may include an implementation of a network environment.

The bus <NUM> may be one or more of several types of bus structures including a storage unit bus or storage unit controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of a variety of bus structures.

The electronic equipment <NUM> may also communicate with one or more external devices <NUM> (e.g., keyboard, pointing device, Bluetooth device, etc.), with one or more devices that enable a user to interact with the electronic equipment <NUM>, and/or with any device (e.g., router, modem, etc.) that enables the electronic equipment <NUM> to communicate with one or more other computing devices. Such a communication may be performed via Input / Output (I/O) interface <NUM>. Also, the electronic equipment <NUM> may communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and/or a public network such as the internet) via the network adapter <NUM>. As shown, the network adapter <NUM> communicates with the other modules of the electronic equipment <NUM> via the bus <NUM>. It should be understood that although not shown in the figures, other hardware and/or software modules may be used in combination with the electronic equipment <NUM>, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, data backup storage systems, and the like.

With the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein may be implemented by software, and may also be implemented by software in combination with necessary hardware. Therefore, the technical solution according to the embodiments of the present disclosure may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (which may be a CD-ROM, a USB disk, a removable hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which may be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the embodiments of the present disclosure.

In one exemplary embodiment of the present disclosure, there is also provided a computer-readable storage medium on which a program product configured to implement the above-described method of the present specification when executed on the processor of electronic equipment according to the present disclosure, is stored. In some possible embodiments, various aspects of the present disclosure may also be implemented in the form of a program product including program code for causing a terminal device of electronic equipment according to the present disclosure to perform the steps according to various exemplary embodiments of the present disclosure as described in the "exemplary method" section above of this specification, when the program product is performed on the terminal device.

Referring to the drawings, a program product <NUM> for implementing the above method according to an embodiment of the present disclosure is described, which may employ a portable compact disc read only memory (CD-ROM) and include program code, and may be performed on the terminal device of electronic equipment according to the present disclosure, such as a personal computer. However, the program product of the present disclosure is not limited thereto, and in this text, a readable storage medium may be any tangible medium that may contain, or store programs for use by or in connection with an instruction execution system, apparatus, or device of electronic equipment according to the present disclosure.

The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

The computer-readable signal medium may include a data signal that is transmitted in base band or as part of a carrier wave, in which readable program code is carried. The propagated data signal may in a variety of forms, including, but not limited to, electromagnetic signals, optical signals, or any suitable combination thereof. The readable signal medium may be any readable medium that is not a readable storage medium and that may communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical cable, RF, etc., or any suitable combination thereof.

The program code for performing operations of the present disclosure may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server. In situations involving remote computing devices, the remote computing devices may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to external computing devices (e.g., through the internet using an internet service provider).

It should be noted that although in the above detailed description, several modules or units of the device for action execution are mentioned, such a division is not mandatory. Indeed, the features and functions of two or more modules or units described above may be embodied in one module or unit, according to embodiments of the present disclosure. In contrast, the features and functions of one module or unit described above may be further divided into embodiments by a plurality of modules or units.

Claim 1:
A method for docking a boarding bridge (<NUM>) with an aircraft (<NUM>), wherein the method comprises:
planning a path (<NUM>) from a position at which a bridgehead (<NUM>) is located when the boarding bridge (<NUM>) is at a parking position to a pre-docking position which is <NUM> to <NUM> meters away from a cabin door (<NUM>) of the aircraft (<NUM>), which comprises: acquiring a preset anti-collision line (<NUM>) of a wing (<NUM>);acquiring a pre-docking position and a position at which the bridgehead (<NUM>) is located when the boarding bridge (<NUM>) is at the parking position, and generating a path (<NUM>) for connecting the two positions; simulating the process of the boarding bridge (<NUM>) moving to the pre-docking position along the path (<NUM>), and adjusting at least a part of the path (<NUM>) in front of an engine (<NUM>) in a direction radially away from the engine (<NUM>) in case that an interference is formed between the anti-collision line (<NUM>) of the wing (<NUM>) and an outer contour of the boarding bridge (<NUM>) during the simulating, and then simulating again unless no more interference between the anti-collision line (<NUM>) of the wing (<NUM>) and the outer contour of the boarding bridge (<NUM>) be formed;
driving the boarding bridge (<NUM>) to move the bridgehead (<NUM>) towards the pre-docking position along the path (<NUM>) until the bridgehead (<NUM>) moves to a position where a distance between the bridgehead (<NUM>) and the pre-docking position is less than <NUM> meters;
acquiring an aircraft image of the aircraft (<NUM>), obtaining a spatial position of the cabin door (<NUM>) according to the aircraft image;
moving the boarding bridge (<NUM>) according to the spatial position to enable the bridgehead (<NUM>) to dock with the cabin door (<NUM>).