Elevator system comprising sensor assembly for detecting loading and unloading of object

Abstract

An elevator system includes: a hoistway; an elevator car configured to travel in the hoistway; a landing having a landing door; a sensor assembly configured to monitor a field of view overlapping a door opening of the landing door; the sensor assembly is configured to perform at least one of: (i) determine a number of objects in the elevator car; (ii) determining a load of an object in the elevator car; and (iii) detecting a door obstacle.

Description

Technical Field

[0001] Embodiments described herein relate to elevator systems and, more particularly, to an elevator system that includes a sensor assembly to detect objects entering and exiting an elevator car. Background Art

[0002] Existing elevator systems employ code-required door obstruction detection systems. Existing elevator systems may also employ people counting systems and load detection systems and re-leveling control systems. The door obstruction detection system, people counting system, load detection system and re-leveling control system are typically implemented using separate devices. Summary of the invention

[0003] According to one embodiment, an elevator system includes: a hoistway; an elevator car configured to travel in the hoistway; a landing having a landing door; a sensor assembly configured to monitor a field of view overlapping with a door opening of the landing door; the sensor assembly is configured to perform at least one of the following operations: (i) determine the number of objects in the elevator car; (ii) determine the load of objects in the elevator car; and (iii) detect a door obstruction.

[0004] Additionally or alternatively to one or more of the features described herein, further embodiments may include wherein the sensor assembly includes a sensor that measures a distance to an object.

[0005] In addition to or in lieu of one or more of the features described herein, further embodiments may include wherein the sensor comprises at least one of a LIDAR sensor, a millimeter wave RADAR sensor, and a RGBD camera.

[0006] In addition to or in lieu of one or more of the features described herein, further embodiments may include wherein the sensor assembly is configured to perform at least two of the following operations: (i) determining the number of objects in the elevator car; (ii) determining the load of objects in the elevator car; and (iii) detecting door obstructions.

[0007] In addition to or in lieu of one or more of the features described herein, further embodiments may include wherein the sensor assembly is configured to perform all of the following operations: (i) determining the number of objects in the elevator car; and (ii) determining the load of objects in the elevator car; and (iii) detecting door obstructions.

[0008] In addition to or in lieu of one or more of the features described herein, further embodiments may include wherein the sensor assembly determines the number of objects in the elevator car by detecting objects entering and exiting the elevator car.

[0009] In addition to or in lieu of one or more of the features described herein, other embodiments may include where the sensor assembly is configured to communicate a number of objects in the elevator car to an elevator controller.

[0010] In addition to or in lieu of one or more of the features described herein, other embodiments may include where the elevator controller is configured to control operation of the elevator system in response to a number of objects in the elevator car.

[0011] In addition to or in lieu of one or more of the features described herein, further embodiments may include where the sensor assembly determines the load of objects in the elevator car by determining a type of each object in the elevator car, where each type of object is associated with a weight.

[0012] Additionally or alternatively to one or more of the features described herein, further embodiments may include wherein the sensor assembly determines the type of each object in the elevator car by comparing sensor data from the sensor to reference data in memory.

[0013] In addition to or in lieu of one or more of the features described herein, other embodiments may include where the sensor assembly is configured to communicate a load of an object in the elevator car to the elevator controller.

[0014] In addition to or in lieu of one or more of the features described herein, other embodiments may include where the elevator controller is configured to perform sag compensation in response to a load of an object in the elevator car.

[0015] Additionally or alternatively to one or more of the features described herein, further embodiments may include wherein the type of each object in the elevator car includes a human and a robot.

[0016] Additionally or alternatively to one or more of the features described herein, further embodiments may include where determining a load of objects in the elevator car includes determining a change in the load of objects in the elevator car.

[0017] According to another embodiment, a method of operating an elevator system, the elevator system comprising: a hoistway; an elevator car configured to travel in the hoistway; and a landing having a landing door; the method comprising: installing a sensor assembly to monitor a field of view overlapping a door opening of the landing door; and using the sensor assembly to perform at least one of the following operations: (i) determining a number of objects in the elevator car; (ii) determining a load of objects in the elevator car; and (iii) detecting a door obstruction.

[0018] Additionally or alternatively to one or more of the features described herein, further embodiments may include wherein using the sensor assembly further includes using the sensor to measure a distance to an object.

[0019] In addition to or in lieu of one or more of the features described herein, further embodiments may include: wherein using the sensor assembly further includes: using at least one of a LIDAR sensor, a millimeter wave RADAR sensor, and a RGBD camera, and the method further includes: using at least one of the LIDAR sensor, the millimeter wave RADAR sensor, and the RGBD camera to measure the distance to an object.

[0020] Additionally or alternatively to one or more of the features described herein, further embodiments may include where determining a load of objects in the elevator car includes determining a change in the load of objects in the elevator car.

[0021] In addition to or in lieu of one or more of the features described herein, other embodiments may include using a sensor assembly to communicate a number of objects in an elevator car to an elevator controller.

[0022] According to another embodiment, a computer program is implemented on a non-transitory computer-readable storage medium, the computer program including instructions for causing a processor to implement a process for operating an elevator system, the elevator system comprising: a shaft; an elevator car configured to travel in the shaft; a landing having a landing door; and a sensor assembly for monitoring a field of view overlapping with a door opening of the landing door; the process comprising: using the sensor assembly to perform at least one of the following operations: (i) determining the number of objects in the elevator car; (ii) determining the load of objects in the elevator car; and (iii) door obstacle detection.

[0023] Unless otherwise expressly indicated, the aforementioned features and elements may be combined in various combinations without exclusivity. These features and elements and their operation will become more apparent from the following description and accompanying drawings. However, it should be understood that the following description and accompanying drawings are intended to be illustrative and explanatory in nature, rather than restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present disclosure is illustrated by way of example and not by way of limitation in the accompanying figures in which like references indicate similar elements.

[0025] Figure 1 An elevator system is shown in which various embodiments of the present disclosure may be employed;

[0026] Figure 2 An elevator door and sensor assembly according to an embodiment is shown;

[0027] Figure 3 illustrates a field of view of a sensor assembly according to an embodiment;

[0028] Figure 4 A sensor assembly according to an embodiment is shown;

[0029] Figure 5 A flow chart showing a process for controlling an elevator system according to an embodiment;

[0030] Figure 6 illustrates detection of a person according to an embodiment; and

[0031] Figure 7 Detection of humans and robots according to an embodiment is shown. DETAILED DESCRIPTION

[0032] Figure 1 1 is a perspective view of an elevator system 101 that includes an elevator car 103, a counterweight 105, a tension member 107, a guide rail 109, a machine 111, a position reference system 113, and a controller 115. The elevator car 103 and the counterweight 105 are connected to each other by the tension member 107. The tension member 107 may include or be configured as, for example, a rope, a steel cable, and / or a coated steel belt. The counterweight 105 is configured to balance the load of the elevator car 103 and is configured to facilitate movement of the elevator car 103 in an elevator shaft or hoistway 117 and along the guide rail 109 relative to the counterweight 105 simultaneously and in opposite directions.

[0033] The tension member 107 engages a machine 111, which is part of the overhead structure of the elevator system 101. The machine 111 is configured to control the movement between the elevator car 103 and the counterweight 105. A position reference system 113 may be mounted on a fixed portion at the top of the elevator shaft 117, such as on a support or rail, and the position reference system 113 may be configured to provide a position signal related to the position of the elevator car 103 within the elevator shaft 117. In other embodiments, the position reference system 113 may be mounted directly to the moving components of the machine 111, or may be located in other locations and / or configurations as known in the art. The position reference system 113 may be any device or mechanism for monitoring the position of the elevator car and / or counterweight as known in the art. For example, without limitation, the position reference system 113 may be an encoder, a sensor, or other system and may include speed sensing, absolute position sensing, etc., as will be appreciated by those skilled in the art.

[0034] As shown, the controller 115 may be located in a controller room 121 of the elevator shaft 117 and configured to control the operation of the elevator system 101, and in particular the elevator car 103. It is to be appreciated that the controller 115 need not be located in the controller room 121, but may be located in the hoistway or other locations in the elevator system. For example, the controller 115 may provide drive signals to the machine 111 to control the acceleration, deceleration, leveling, stopping, etc. of the elevator car 103. The controller 115 may also be configured to receive position signals from the position reference system 113 or any other desired position reference device. When moving up or down along the guide rails 109 in the elevator shaft 117, the elevator car 103 may stop at one or more landings 125 as controlled by the controller 115. Although shown in the controller room 121, those skilled in the art will appreciate that the controller 115 may be located and / or configured in other locations or positions within the elevator system 101. In one embodiment, the controller 115 may be remotely located or located in a distributed computing network (eg, a cloud computing architecture). The controller 115 may be implemented using a processor-based machine such as a personal computer, a server, a distributed computing network, or the like.

[0035] The machine 111 may include a motor or similar drive mechanism. According to an embodiment of the present disclosure, the machine 111 is configured to include an electrically driven motor. The power source for the motor may be any power source (including the electrical grid), which (in combination with other components) is supplied to the motor. The machine 111 may include a traction wheel that transmits force to the tension member 107 to move the elevator car 103 within the elevator shaft 117.

[0036] The elevator system 101 also includes one or more elevator doors 104. The elevator doors 104 may be attached to the elevator car 103, or the elevator doors 104 may be located on a landing 125 of the elevator system 101, or both. The embodiments disclosed herein may be applicable to elevator doors 104 attached to the elevator car 103, or elevator doors 104 located on a landing 125 of the elevator system 101, or both. The elevator doors 104 open to allow passengers to enter and exit the elevator car 103.

[0037] Although shown and described using a roping system including tension members 107, elevator systems that use other methods and mechanisms for moving an elevator car within an elevator shaft may employ embodiments of the present disclosure. For example, embodiments may be used in ropeless elevator systems that use linear motors to impart motion to an elevator car. Embodiments may also be employed in ropeless elevator systems that use hydraulic lift to impart motion to an elevator car. Embodiments may also be employed in ropeless elevator systems that use self-propelled elevator cars, such as elevator cars equipped with friction wheels, motorized wheels for climbing beams, hold-down wheels, or traction wheels. Figure 1 These are non-limiting examples presented for purposes of illustration and explanation only.

[0038] Figure 2 Elevator door 104 and sensor assembly 220 are shown in an example embodiment. Figure 2 The elevator door 104 in FIG. 1 is a landing door. This sensor assembly 220 can be positioned at a corner of the door 104 where the field of view 150 overlaps the door opening. The field of view 150 can be two-dimensional or three-dimensional. Figure 2 In the example of FIG. 1 , the field of view 150 includes 90 degrees in the plane of the opening of the door 104 and + or −15 to 25 degrees in the out-of-plane area, such as Figure 3 as shown in . Figure 3 is a top view at the door 104. This field of view 150 allows the sensor assembly 220 to obtain sensor data of objects entering the elevator car 103. The sensor data can be post-processed at the sensor assembly 220 to determine the number, load, and direction of movement of the objects. As used herein, objects may include people (adults and children), cargo, robots (e.g., automated guided vehicles), etc.

[0039] Figure 4The sensor assembly 220 in the example embodiment is shown. The sensor assembly 220 includes a sensor 222. The sensor 222 can be a distance sensor that generates distance measurements in a two-dimensional or three-dimensional field of view 150. The sensor 222 can be implemented using a LIDAR sensor, a millimeter wave RADAR sensor, an RGBD camera, or other distance measurement sensors. The sensor assembly 220 includes a processor 224 that controls the operation of the sensor assembly 220. The processor 224 can be implemented using a general-purpose microprocessor that executes a computer program stored on a storage medium to perform the operations described herein. Alternatively, the processor 224 can be implemented in hardware (e.g., ASIC, FPGA) or in a combination of hardware / software. The processor 224 allows the sensor assembly 220 to perform calculations locally, also known as edge computing. The processor 224 is capable of sending commands to other components of the elevator system 101 based on the results of the local calculations.

[0040] The sensor assembly 220 includes a memory 226 that can store computer programs executable by the processor 224, reference data, sensor data, etc. The memory 226 can be implemented using known devices such as random access memory. The sensor assembly 220 includes a communication unit 228 that allows the sensor assembly 220 to communicate with other components of the elevator system 101 (such as the elevator controller 115). The communication unit 228 can be implemented using a wired connection (e.g., LAN, Ethernet, twisted pair, etc.) or a wireless connection (e.g., WiFi, NFC, Bluetooth, etc.).

[0041] In operation, the sensor assembly 220 can perform local determination of objects entering and exiting the elevator car 103. The sensor assembly 220 can perform counting of objects entering and exiting the elevator car 103 and provide this count to the elevator controller 115. The sensor assembly 220 can also determine the car load when objects enter and exit the elevator car 103. The car load can be used for sag compensation, as described herein.

[0042] Figure 5 A flow chart of a process for controlling an elevator system in an example embodiment is shown. At 500, the sensor assembly 220 at the elevator car door 104 is activated. In an example embodiment, the sensor assembly 220 is always active and acquires sensor data. In an alternative embodiment, the sensor assembly 220 may be activated when the elevator car 103 stops at a landing or only when the door 104 is opened. This can save power usage and reduce unnecessary sensor data.

[0043] At 501, the sensor assembly 220 provides door obstruction detection. The sensor assembly 220 initiates door obstruction detection upon opening of the door 104, which is required by certain codes. Upon detecting an object in the field of view 150, the sensor assembly 220 can prevent movement of the door 104 or command the door 104 to move to an open position. The sensor assembly 220 can communicate with a door controller in the elevator car 103 to control the movement of the door 104.

[0044] At 502, the sensor assembly 220 detects object(s) entering or exiting the elevator car 103. The detection of the object entering or exiting the elevator car 103 is performed by the processor 224. The sensor 222 generates distance data representing the distance of the object from the sensor 222. Figure 6 103. The distance data obtained by the sensor 222 when a person enters the elevator car 103 is shown. When no object is at the door, background distance measurements are collected to establish a baseline. Then, when an object (human, robot, cargo, etc.) appears in the foreground (front) of the learned environmental background, the object can be classified by the processor 224. The distance data obtained by the sensor 222 can be compared with a threshold to confirm that the object has a sufficient size to be marked as an object. For example, if the sensor 222 generates several points per scan of the field of view 150, the number of points must be greater than the threshold to confirm that the object exists. The direction of travel of the object is also determined (e.g., by comparing the distribution of points across multiple frames of the field of view 150) to verify whether the object is entering or leaving the elevator car 103.

[0045] At 504, the sensor assembly 220 determines the number of objects in the elevator car 103. An object may be any item of sufficient size to factor into the operation of the elevator system 101. Example objects include people (adults and children), cargo, robots, and the like.

[0046] At 506, the sensor assembly 220 sends the count of objects in the elevator car 103 to the elevator controller 115. This may be done using the communication unit 228.

[0047] At 508, the elevator controller 115 can then control the operation of the elevator system 101 based on the number of objects in the elevator car 103. The number of objects in the elevator car 103 can affect several parameters of the operation of the elevator system 101. For example, if the elevator car 103 is full (e.g., the number of objects is greater than a limit), the elevator controller 115 will not assign additional calls to the full elevator car 103. Determining the number of objects in the elevator car 103 also helps detect "piggybacking," where a group of people who make a single destination call but are all heading to the same destination floor board the elevator car 103. The number of objects in the elevator car 103 can also be used to pre-twist the machine 111 so that the elevator car 103 does not rise or fall when the machine brakes are released (lifted). The number of objects in the elevator car 103 can also be used to adjust the opening and closing times of the doors 104. Less crowded elevator cars 103 can take advantage of shorter opening and closing times of the doors 104, resulting in faster travel times.

[0048] At 510, the sensor assembly 220 determines the load of objects in the elevator car 103. Determining the load of objects may be performed by classifying each object into an object type. The memory 226 of the sensor assembly 220 may store a weight associated with each type of object. Figure 7 An example of two types of objects (people and robots) is shown. Sensor component 220 is able to classify these objects based on sensor data from sensor 222. The data from sensor 222 can be considered as a camera or photo image, including range data (also known as depth) for each pixel in the image. This increased sensing input from the range of the depth sensor enables robust classification of objects. Processor 224 can compare the sensor data from sensor 222 with reference data in memory 226. The reference data in memory 226 may include reference data for multiple types of objects such as people (adults and children), cargo, robots, etc. When the sensor data from sensor 222 matches the reference data in memory 226, the type of object is determined.

[0049] Determining the load at 514 can include determining a load change rather than a total load in the elevator car 103. As described in more detail herein, sag compensation can be performed based on load changes, thereby eliminating the need to determine the total load in the elevator car 103.

[0050] Each type of object is associated with a weight in memory 226. For example, a person may be associated with a weight of 70 kilograms, and a robot may be associated with a weight of 150 kilograms. Unclassified objects (e.g., objects assigned an "unknown" type that do not match any reference data) may be assigned a default weight. Sensor assembly 220 accumulates the weight associated with each type of object in elevator car 103 and sends the load of elevator car 103 to the elevator controller at 512.

[0051] At 514, the elevator controller 115 performs a sag compensation process. Sag refers to the elongation of the tension member(s) 107 due to factors including the load in the elevator car 103, the location of the elevator car 103 in the hoistway 117, the number, size, and type of tension members 107, etc. When the elevator car 103 is parked at a landing, the elongation of the tension members 107 can cause the elevator car 103 to be misaligned with the landing sill, creating a tripping hazard for passengers or an uneven surface that causes problems moving cargo or robots across the sill.

[0052] Based on the load in the elevator car 103 and other factors, the elevator controller 115 determines a sag compensation value that corresponds to the distance the elevator car 103 needs to be moved in order to compensate for the sag. The elevator controller 115 causes the machine 111 to move the elevator car 103 to compensate for the sag. As described above, the sensor assembly 220 determines the load in the elevator car 103, which may be a total load or a load change. The controller 115 knows the landing being served and stores an estimate of the stiffness of the tension member 107 (rope or belt) at that landing location in its local memory. The sag compensation can be determined by dividing the load change by the controller 115's stored value of the rope stiffness at the indicated landing location. The sag compensation performed by the controller 115 may smooth out load changes (loading and unloading) over time and also limit the rate of change of the compensation to avoid sudden car movement.

[0053] The controller 115 may integrate the sag compensation at 514 into an existing baseline re-leveling mode that adjusts the motor position based on the sensed amount of car sag from the position vane or position reference system 113. The baseline re-leveling function is reactive, using feedback. The sag compensation at 514 is proactive, using feed-forward logic that can be summed (or integrated) with the motor commands of the feedback logic.

[0054] Figure 5 The steps can be repeated as needed.

[0055] The embodiments described herein allow for a single sensor assembly that provides the code-enforced functionality of door obstruction monitoring and, when combined with data processing, is also able to isolate and count passengers and their movements into or out of an elevator car. This information can be used to optimize elevator operations, such as dispatch and group control, without violating the privacy issues associated with camera-based monitoring systems. Currently, this type of usage data is not available using existing elevator sensors, such as load weighing, which only monitor changes in load, but do not detect or measure individual load transfers out and into the elevator at each stop. The embodiments also provide a solution to the elevator sag problem by using a sensor assembly to monitor time-varying load transfer data and including it as an open-loop feed-forward compensation to limit dynamic sag.

[0056] As described above, embodiments may take the form of processor-implemented processes and apparatus for practicing those processes, such as processor 224 in sensor assembly 220. Embodiments may also take the form of computer program code containing instructions implemented in a tangible medium, such as a network cloud storage device, an SD card, a flash drive, a floppy disk, a CD ROM, a hard drive, or any other computer-readable storage medium, wherein when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the embodiments. Embodiments may also take the form of, for example, computer program code stored in a storage medium, loaded into and / or executed by a computer, or transmitted through some transmission medium, loaded into and / or executed by a computer, or transmitted through some transmission medium, such as through wires or cables, through fiber optics, or via electromagnetic radiation; wherein when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.

[0057] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when used in this specification, the terms "include" and / or "comprises" (comprises, comprising) specify the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups of the above items.

[0058] Although the present disclosure has been described with reference to one or more exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from the scope of the present disclosure. In addition, various modifications may be made to adapt a particular condition or material to the teachings of the present disclosure without departing from its substantial scope. Therefore, it is contemplated that the present disclosure is not limited to the specific embodiments disclosed as the best mode contemplated for carrying out the present disclosure, but rather the present disclosure will include all embodiments falling within the scope of the claims.

Claims

1. An elevator system, comprising: Well; an elevator car configured to travel in the hoistway; Landing station, with landing door; a sensor assembly configured to monitor a field of view overlapping a door opening of the landing door; wherein the sensor assembly is configured to perform at least one of the following operations: (i) determine a number of objects in the elevator car; (ii) determine a load of objects in the elevator car; and (iii) detecting door obstructions.

2. The elevator system according to claim 1, wherein: The sensor assembly includes a sensor that measures a distance to an object.

3. The elevator system according to claim 2, wherein: The sensor includes at least one of a LIDAR sensor, a millimeter wave RADAR sensor, and an RGBD camera.

4. The elevator system according to claim 1, wherein: The sensor assembly is configured to perform at least two of the following operations: (i) determine the number of objects in the elevator car; (ii) determine the load of objects in the elevator car; and (iii) detecting the door obstruction.

5. The elevator system according to claim 1, wherein: The sensor assembly is configured to perform all of the following operations: (i) determine the number of objects in the elevator car; and (ii) determine the load of objects in the elevator car; and (iii) detecting the door obstruction.

6. The elevator system according to claim 1, wherein: The sensor assembly determines the number of objects in the elevator car by detecting objects entering and exiting the elevator car.

7. The elevator system according to claim 1, wherein: The sensor assembly is configured to communicate the number of objects in the elevator car to an elevator controller.

8. The elevator system according to claim 7, wherein: The elevator controller is configured to control operation of the elevator system in response to the number of objects in the elevator car.

9. The elevator system according to claim 1, wherein: The sensor assembly determines the load of the objects in the elevator car by determining a type of each object in the elevator car, wherein each type of object is associated with a weight.

10. The elevator system according to claim 9, wherein: The sensor assembly determines the type of each object in the elevator car by comparing sensor data from sensors to reference data in memory.

11. The elevator system according to claim 9, wherein: The sensor assembly is configured to communicate the load of the object in the elevator car to an elevator controller.

12. The elevator system of claim 11, wherein: The elevator controller is configured to perform sag compensation in response to the load of the object in the elevator car.

13. The elevator system of claim 9, wherein: The types of each object in the elevator car include a human and a robot.

14. The elevator system of claim 1, wherein: Determining the load of objects in the elevator car includes determining a change in the load of objects in the elevator car.

15. A method of operating an elevator system, the elevator system comprising a hoistway, an elevator car configured to travel in the hoistway, and a landing having a landing door, the method comprising: installing a sensor assembly to monitor a field of view overlapping a door opening of the landing door; as well as Using the sensor assembly to perform at least one of the following operations: (i) determining a number of objects in the elevator car; (ii) determining a load of objects in the elevator car; and (iii) detecting door obstructions.

16. The method of claim 15, wherein: Using the sensor assembly further includes using the sensor to measure a distance to an object.

17. The method of claim 15, wherein: Using the sensor assembly further includes using at least one of a LIDAR sensor, a millimeter wave RADAR sensor, and an RGBD camera, and the method further includes: A distance to an object is measured using at least one of the LIDAR sensor, the millimeter wave RADAR sensor, and the RGBD camera.

18. The method of claim 15, wherein: Determining the load of objects in the elevator car includes determining a change in load of objects in the elevator car.

19. The method of claim 15, further comprising communicating the number of objects in the elevator car to an elevator controller using the sensor assembly.

20. A computer program implemented on a non-transitory computer readable storage medium, the computer program comprising instructions for causing a processor to implement a process for operating an elevator system, the elevator system comprising a hoistway, an elevator car configured to travel in the hoistway, a landing having a landing door, and a sensor assembly for monitoring a field of view overlapping a door opening of the landing door, the process comprising: Using the sensor assembly to perform at least one of the following operations: (i) determining a number of objects in the elevator car; (ii) determining a load of objects in the elevator car; and (iii) door obstacle detection.

Images