Unattended clinker screw conveyor port remote control system

Abstract

The invention discloses an unattended clinker screw conveyor port remote control system which comprises a conveyor, the conveyor comprises a base column, a vertical screw conveying pipe and a material taking head, and a detection device is arranged at the tail section position of the vertical screw conveying pipe. The detection device comprises a visual detection device and a laser distance measuring device matched with the visual detection device, and the base column, the horizontal spiral conveying pipe, the vertical spiral conveying pipe and the material taking head are each provided with a position sensor. The horizontal swing driving device, the horizontal rotation driving device, the vertical rotation driving device and the material taking swing driving device are each provided with a first rotary encoder, and the cloud platform is provided with three-dimensional models corresponding to the base column, the horizontal spiral conveying pipe, the vertical spiral conveying pipe and the material taking head. The deformation change of the material three-dimensional virtual model is generated through the material three-dimensional virtual model and the material conveying efficiency of the material taking head, and then the three-dimensional pose of the material taking head is adjusted.

Description

Technical Field

[0001] The present invention relates to the field of automated port equipment, and in particular to an unmanned clinker screw conveyor port remote control system. Background Art

[0002] Port clinker conveyors are generally used to transport large volumes of materials. However, with the development of automated equipment, they are also used on large-volume equipment. The key to achieving unmanned operation lies in the real-time operation of the machinery and the stable feeding of the clinker screw conveyor during the conveying process. The key points are:

[0003] 1. How to realize remote identification and control of materials when there is no one on duty;

[0004] 2. How to ensure safe transportation and control when the machinery is delayed?

[0005] 3. How to achieve remote control between the clinker conveyor and the cloud platform, and enable precise control by the operator;

[0006] 4. The material is mainly clinker, so it is in granular form (such as cement, mud, etc.). Therefore, the change of the material pile is an arc-shaped change (quicksand change), which is non-standard. Therefore, how to realize automatic material search is also one of the key points of the design. The existing practice generally uses a position sensor to realize the relative distance between the material reclaiming head and the material, and then extends the reclaiming head into the material pile. However, when the depth of the reclaiming head is greater than the preset value, it is easy to cause the material to be unable to be transported (too large resistance) or the transported material to clump (causing idling), thereby affecting the conveying efficiency.

[0007] Therefore, how to detect the material pile and adjust the position of the material head in time is the key point of automatic loading. Summary of the Invention

[0008] The main purpose of this invention is to propose an unmanned clinker screw conveyor port remote control system, which aims to realize unmanned clinker screw conveying through limited machine permissions, reduce manual operation during the conveying process, and thus improve work efficiency.

[0009] The unmanned operation is limited to unmanned operation during the transportation process, which reduces the redundant time of monitoring and ensures work efficiency.

[0010] In the actual initial stage of operation and authority control are mainly done by manual operation, and the unmanned operation mainly uses the screw conveyor to automatically plan the path according to the changes in the passing materials.

[0011] To achieve the above object, the present invention proposes an unmanned clinker screw conveyor port remote control system, comprising a conveyor,

[0012] The conveyor comprises:

[0013] The top of the base column is pivotally mounted with a horizontal spiral conveying pipe, and the top of the base column is provided with a horizontal swing driving device for driving the horizontal spiral conveying pipe to rotate horizontally.

[0014] A horizontal spiral blade shaft is provided in the horizontal spiral conveying pipe for rotation, and a horizontal rotation driving device is provided at the rear end of the horizontal spiral conveying pipe for driving the horizontal spiral blade shaft to rotate;

[0015] A vertical spiral conveying pipe, the top end of which is swingably mounted on the end of the horizontal spiral conveying pipe, and the base column and the horizontal spiral conveying pipe are provided with a vertical swing driving device for driving the vertical spiral conveying pipe to swing.

[0016] The vertical spiral conveying pipe is provided with a rotatable spiral conveying shaft, and the rear end of the vertical spiral conveying pipe is provided with a vertical rotation driving device for driving the spiral conveying shaft to rotate;

[0017] The material taking head is swingably arranged at the end of the vertical spiral conveying pipe, the vertical spiral conveying pipe is provided with a material taking swing driving device for driving the material taking head to swing, and the material taking head is provided with a material taking rotation driving device for driving the material taking shaft to rotate;

[0018] The detection device is located at the end of the vertical spiral conveying pipe and includes a visual detection device and a laser distance measuring device coordinated with the visual detection device.

[0019] The base column, horizontal spiral conveying pipe, vertical spiral conveying pipe and material taking head are respectively provided with position sensors.

[0020] The horizontal swing drive device, the horizontal rotation drive device, the vertical rotation drive device and the material-taking swing drive device are respectively provided with a first rotary encoder;

[0021] The cloud platform is provided with a three-dimensional model corresponding to the base column, the horizontal spiral conveyor pipe, the vertical spiral conveyor pipe and the material taking head.

[0022] The three-dimensional model obtains the three-dimensional position and posture of the conveyor through the position sensor and the first rotary encoder;

[0023] Fitting a three-dimensional surface: first, the visual detection device is used to obtain image data within a predetermined range of the material picking head, and then the convex and concave images are marked by the image data.

[0024] Then the laser distance measuring device measures the distance of the convex surface and the concave surface respectively and obtains the first position and the second position, and generates a three-dimensional virtual model of the material through fitting the image data and the relative distance between the first position and the second position.

[0025] And through the three-dimensional virtual model of the material and the conveying efficiency of the reclaiming head on the material, the deformation change of the three-dimensional virtual model of the material is generated, and then the three-dimensional posture of the reclaiming head is adjusted.

[0026] This application has the following advantages:

[0027] 1. The first rotary encoder and position sensor are set on each mechanism of the conveyor to accurately obtain the relative positions of the horizontal spiral conveyor pipe, vertical spiral conveyor pipe and material reclaiming head.

[0028] The three-dimensional position (Xn, Yn, Zn) of the reclaiming head is adjusted by adjusting the relative position of each mechanism. In addition, each mechanism adopts at least two sets of relative position monitoring devices to reduce the problem of reclaiming head collision, thereby improving the safety of the conveyor and improving the safety of use.

[0029] At the same time, when a fault occurs, the position can be accurately adjusted or the work can be stopped, thereby improving the stability of automatic work;

[0030] 2. Set up a proportional 3D model on the cloud platform, so that the virtual position of the conveyor can be clearly known in the computer operation room.

[0031] In order to save computing power, the conveyor can be operated manually. For the transportation of main materials, the predetermined material picking position can be selected through the three-dimensional virtual model of the material on the cloud platform, thereby reducing manual real-time operation and the problem of manual monitoring, and realizing unmanned material picking.

[0032] 3. Unlike existing designs, the existing single laser ranging generation model requires a large amount of data collection, so the corresponding cloud platform has a large amount of computing power, which will cause a large lag in industrial production, affecting production stability, and its data cannot be changed according to actual needs;

[0033] 4. The cloud platform can obtain the optimal material picking position based on the changes in the three-dimensional virtual model of the material, thereby improving efficiency, reducing manual intervention, and realizing unattended material picking;

[0034] 5. Compared with 3D scanning devices, its equipment cost is lower and its fault tolerance is lower. The existing 3D scanning devices are expensive and have a high damage rate in industrial applications. They mainly use high-precision lenses.

[0035] The laser distance measuring device and the visual inspection device can be selected for applicability according to the volume of the material pile. At the same time, they are more energy-efficient than three-dimensional scanning devices. At the same time, the material changes can be monitored through the rotation network (rotationnet), which can improve the stability of material changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the conveyor;

[0037] Figure 2 It is a schematic diagram of the material plane image;

[0038] Figure 3 It is the cross-sectional view of the three-dimensional virtual model of the material after fitting;

[0039] Figure 4 Schematic diagram of a virtual fence;

[0040] Figure 5 This is a block diagram of the present invention.

[0041] In the figure,

[0042] 1 is the base column, 11 is the horizontal spiral conveying pipe, 12 is the vertical spiral conveying pipe, 13 is the material taking head,

[0043] 21 is the first position and 22 is the second position. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0045] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom, inside, outside, vertical, horizontal, longitudinal, counterclockwise, clockwise, circumferential, radial, axial...), then the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0046] In addition, if there are descriptions involving "first" or "second" in the embodiments of the present invention, the descriptions of "first" or "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0047] like Figures 1 to 5 As shown, an unmanned clinker screw conveyor port remote control system, including a conveyor,

[0048] The conveyor comprises:

[0049] The top of the base column 1 is pivotally mounted with a horizontal spiral conveying pipe 11, and the top of the base column 1 is provided with a horizontal swing driving device for driving the horizontal spiral conveying pipe 11 to rotate horizontally.

[0050] A horizontal screw blade shaft is provided in the horizontal spiral conveying pipe 11 for rotation, and a horizontal rotation driving device is provided at the rear end of the horizontal spiral conveying pipe 11 for driving the horizontal screw blade shaft to rotate;

[0051] The vertical spiral conveying pipe is swingably mounted on the end of the horizontal spiral conveying pipe 11. The base column 1 and the horizontal spiral conveying pipe 11 are provided with a vertical swing driving device for driving the vertical spiral conveying pipe to swing.

[0052] The vertical spiral conveying pipe is provided with a rotatable spiral conveying shaft, and the rear end of the vertical spiral conveying pipe is provided with a vertical rotation driving device for driving the spiral conveying shaft to rotate;

[0053] The material taking head is swingably arranged at the end of the vertical spiral conveying pipe, the vertical spiral conveying pipe is provided with a material taking swing driving device for driving the material taking head to swing, and the material taking head is provided with a material taking rotation driving device for driving the material taking shaft to rotate;

[0054] The detection device is located at the end of the vertical spiral conveying pipe and includes a visual detection device and a laser distance measuring device coordinated with the visual detection device.

[0055] The base column 1, the horizontal spiral conveying pipe 11, the vertical spiral conveying pipe and the material taking head are respectively provided with position sensors.

[0056] The horizontal swing drive device, the horizontal rotation drive device, the vertical rotation drive device and the material-taking swing drive device are respectively provided with a first rotary encoder;

[0057] The cloud platform is provided with a three-dimensional model corresponding to the base column 1, the horizontal spiral conveying pipe 11, the vertical spiral conveying pipe and the material taking head.

[0058] The three-dimensional model obtains the three-dimensional position and posture of the conveyor through the position sensor and the first rotary encoder;

[0059] Fitting a three-dimensional surface: first, the visual detection device is used to obtain image data within a predetermined range of the material picking head, and then the convex and concave images are marked by the image data.

[0060] Then the laser distance measuring device measures the distance of the convex surface and the concave surface respectively and obtains the first position and the second position, and generates a three-dimensional virtual model of the material through fitting the image data and the relative distance between the first position and the second position.

[0061] And through the three-dimensional virtual model of the material and the conveying efficiency of the reclaiming head on the material, the deformation change of the three-dimensional virtual model of the material is generated, and then the three-dimensional posture of the reclaiming head is adjusted.

[0062] This application has the following advantages:

[0063] 1. Each mechanism of the conveyor is equipped with a first rotary encoder and a position sensor so as to accurately obtain the relative positions of the horizontal spiral conveyor pipe 11, the vertical spiral conveyor pipe and the material taking head.

[0064] The three-dimensional position (Xn, Yn, Zn) of the reclaiming head is adjusted by adjusting the relative position of each mechanism. In addition, each mechanism adopts at least two sets of relative position monitoring devices to reduce the problem of reclaiming head collision, thereby improving the safety of the conveyor and improving the safety of use.

[0065] At the same time, when a fault occurs, the position can be accurately adjusted or the work can be stopped, thereby improving the stability of automatic work;

[0066] 2. Set up a proportional 3D model on the cloud platform, so that the virtual position of the conveyor can be clearly known in the computer operation room.

[0067] In order to save computing power, the conveyor can be operated manually. For the transportation of main materials, the predetermined material picking position can be selected through the three-dimensional virtual model of the material on the cloud platform, thereby reducing manual real-time operation and the problem of manual monitoring, and realizing unmanned material picking.

[0068] 3. Unlike existing designs, the existing single laser ranging generation model requires a large amount of data collection, so the corresponding cloud platform has a large amount of computing power, which will cause a large lag in industrial production, affecting production stability, and its data cannot be changed according to actual needs;

[0069] 4. The cloud platform can obtain the optimal material picking position based on the changes in the three-dimensional virtual model of the material, thereby improving efficiency, reducing manual intervention, and realizing unattended material picking;

[0070] 5. Compared with 3D scanning devices, its equipment cost is lower and its fault tolerance is lower. The existing 3D scanning devices are expensive and have a high damage rate in industrial applications. They mainly use high-precision lenses.

[0071] The laser distance measuring device and the visual inspection device can be selected for applicability according to the volume of the material pile. At the same time, they are more energy-efficient than three-dimensional scanning devices. At the same time, the material changes can be monitored through the rotation network (rotationnet), which can improve the stability of material changes.

[0072] The additional visual detection device and laser detection device are arranged on the horizontal spiral conveyor pipe 11 to reduce the interference of foreign objects and improve the stability of detection. It is a good reference model for this type of large machinery, which can realize position detection and material detection with less interference from foreign objects.

[0073] In an embodiment of the invention,

[0074] The material is granular or powdery.

[0075] The arc-shaped transition between the convex surface and the concave surface is defined as a slope.

[0076] During the image data forming process, the inclined surface is directly fitted into the three-dimensional model with the shortest distance between the convex surface and the concave surface, thereby reducing the complexity of the calculation, and the relative position of the material taking head can be adjusted in real time by real-time monitoring of the material changes.

[0077] In an embodiment of the invention, the cloud platform obtains the material range through a visual detection device and a laser range-finding device or obtains the material range through a position sensor before taking the material;

[0078] The cloud platform generates a virtual position fence based on the material range, and the virtual position fence is used to limit the maximum range of movement of the horizontal spiral conveying pipe 11, the vertical spiral conveying pipe and the material taking head.

[0079] In an embodiment of the invention, the process of generating the three-dimensional virtual model of the material includes:

[0080] Step 1: The visual inspection device acquires image data within a predetermined range, pixelates the image data and generates a coordinate system (Xi, Yi);

[0081] Step 2: Filter the color of the image data through the filter, and then mark the convex and concave surfaces separately.

[0082] By comparing the image data of the filter, the first position and the second position are marked one by one.

[0083] The second positions of the concave surface are arranged in a ring shape, while the second positions of the convex surface are distributed in a point shape or a block shape;

[0084] Step 3: The laser distance measuring device measures the distance of the first position one by one to obtain the first distance Z1i, and measures the distance of the second position to obtain the second distance Z2i.

[0085] Step 4: Generate a fitting three-dimensional model by using a rotation network to combine the coordinate system (Xi, Yi), the first distance Z1i and the second distance Z2i.

[0086] Among them, the rotation network (RotationNet) is an existing technology. In addition to extracting view features, it also uses viewpoint labels as latent variables and jointly estimates their posture and object category, thereby improving the recognition ability of 3D models to a certain extent. Material changes can be obtained through simple calculations.

[0087] In an embodiment of the invention, when the color of the material or the particles of the material are different, the visual inspection device applies a filter to the image data.

[0088] The filter is a color filter, which reveals the convex and concave surfaces after passing through the filter. Different materials have different reflectivity and density, so the products are presented differently in the image data.

[0089] In an embodiment of the invention, the horizontal rotation drive device, the vertical rotation drive device and the material taking rotation device are respectively provided with a second rotary encoder.

[0090] When the second rotary encoder detects that the number of revolutions of the predetermined rotation driving device is less than the predetermined number of revolutions,

[0091] The scheduled material is blocked or loaded;

[0092] When the second rotary encoder detects that the number of revolutions of the predetermined rotary drive device is greater than the predetermined number of revolutions, the predetermined shaft is idling or the conveying amount of the material is less than the predetermined value,

[0093] Then the cloud platform controls the monitoring device to monitor the location of the material pile.

[0094] Then adjust the relative feeding position of the feeding port.

[0095] In an embodiment of the invention, the cloud platform is provided with a material viscosity compensation module, which is used to adapt to materials of different densities and provide feedback to the second rotary encoder. In the actual material viscosity compensation module, after the conveyor runs for a predetermined time, the predetermined number of revolutions of the second rotary encoder is obtained and used as a predetermined reference value, and the range of the predetermined reference value is set.

[0096] The material viscosity compensation module can then be stored.

[0097] In an embodiment of the invention, the horizontal rotation drive device, the vertical rotation drive device and the material picking rotation device are respectively provided with vibration sensors. The vibration sensors judge the conveying condition of the material according to the rotation vibration frequency of the conveying shaft, and combine the data of the vibration sensor and the data of the second rotary encoder to judge the material condition of the conveying pipeline, thereby improving the working monitoring stability of the conveyor.

[0098] In an embodiment of the invention, the path of the reclaiming head is based on the historical data training of the clinker fluidity prediction model to optimize the reclaiming path.

[0099] The prediction model includes a rotation network and a training model, and the prediction model is used to obtain a predetermined material taking position of the inclined surface and a penetration depth of the material taking head.

[0100] In an embodiment of the invention, the training model is a decision tree model. Of course, the existing AI model can also be used to select the optimal route and combine with the rotating network to obtain the clinker fluidity.

[0101] Specifically, in actual laser ranging detection, the detection speed can be set according to the density and support of the material, and the flow changes of the clinker pile can also be obtained through the model.

[0102] The adjustment of posture is an existing technology.

[0103] Specifically, the base column 1 may also be provided with a lifting shaft.

[0104] Although this system is unmanned, it is subject to industry regulations and safety standards, so staff are still available to provide guidance.

[0105] The design also includes anti-collision systems, emergency avoidance systems, emergency handling systems, etc., so as to realize the automated production of this system while ensuring basic safety.

[0106] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. An unmanned clinker screw conveyor port remote control system, characterized in that: Including conveyor, The conveyor comprises: The top of the base column is pivotally mounted with a horizontal spiral conveying pipe, and the top of the base column is provided with a horizontal swing driving device for driving the horizontal spiral conveying pipe to rotate horizontally. A horizontal spiral blade shaft is provided in the horizontal spiral conveying pipe for rotation, and a horizontal rotation driving device is provided at the rear end of the horizontal spiral conveying pipe for driving the horizontal spiral blade shaft to rotate; A vertical spiral conveying pipe, the top end of which is swingably mounted on the end of the horizontal spiral conveying pipe, and the base column and the horizontal spiral conveying pipe are provided with a vertical swing driving device for driving the vertical spiral conveying pipe to swing. The vertical spiral conveying pipe is provided with a rotatable spiral conveying shaft, and the rear end of the vertical spiral conveying pipe is provided with a vertical rotation driving device for driving the spiral conveying shaft to rotate; The material taking head is swingably arranged at the end of the vertical spiral conveying pipe, the vertical spiral conveying pipe is provided with a material taking swing driving device for driving the material taking head to swing, and the material taking head is provided with a material taking rotation driving device for driving the material taking shaft to rotate; The detection device is located at the end of the vertical spiral conveying pipe and includes a visual detection device and a laser distance measuring device coordinated with the visual detection device. The base column, horizontal spiral conveying pipe, vertical spiral conveying pipe and material taking head are respectively provided with position sensors. The horizontal swing drive device, the horizontal rotation drive device, the vertical rotation drive device and the material-taking swing drive device are respectively provided with a first rotary encoder; The cloud platform is provided with a three-dimensional model corresponding to the base column, the horizontal spiral conveyor pipe, the vertical spiral conveyor pipe and the material taking head. The three-dimensional model obtains the three-dimensional position and posture of the conveyor through the position sensor and the first rotary encoder; Fitting a three-dimensional surface: first, the visual detection device is used to obtain image data within a predetermined range of the material picking head, and then the convex and concave images are marked by the image data. The laser ranging device then measures the distance of the convex surface and the concave surface respectively and obtains the first position and the second position, and generates a three-dimensional virtual model of the material by fitting the image data and the relative distance between the first position and the second position. The deformation change of the three-dimensional virtual model of the material and the conveying efficiency of the material taking head are generated, and the three-dimensional posture of the material taking head is adjusted.

2. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The material is granular or powdery. The arc-shaped transition between the convex surface and the concave surface is defined as a slope. During the image data forming process, the inclined surface is directly fitted to form a three-dimensional model with the shortest distance between the convex surface and the concave surface.

3. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The cloud platform obtains the material range through a visual detection device and a laser distance measuring device or obtains the material range through a position sensor before taking the material; The cloud platform generates a virtual position fence based on the material range, and the virtual position fence is used to limit the maximum range of movement of the horizontal spiral conveyor pipe, the vertical spiral conveyor pipe and the material taking head.

4. The unmanned clinker screw conveyor port remote control system according to claim 2, characterized in that: The material three-dimensional virtual model generation process includes: Step 1: The visual inspection device acquires image data within a predetermined range, pixelates the image data and generates a coordinate system (Xi, Yi); Step 2: Filter the color of the image data through the filter, and then mark the convex and concave surfaces separately. By comparing the image data of the filter, the first position and the second position are marked one by one. The second positions of the concave surface are arranged in a ring shape, while the second positions of the convex surface are distributed in a point shape or a block shape; Step 3: The laser distance measuring device measures the distance of the first position one by one to obtain the first distance Z1i, and measures the distance of the second position to obtain the second distance Z2i. Step 4: Generate a fitting three-dimensional model by using a rotation network to combine the coordinate system (Xi, Yi), the first distance Z1i and the second distance Z2i.

5. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: When the color of the material or the particles of the material are different, the visual inspection device applies a filter to the image data. The filter is a color filter, and the convex surface and the concave surface are revealed after passing through the filter.

6. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The horizontal rotation drive device, the vertical rotation drive device and the material taking rotation device are respectively provided with a second rotary encoder. When the second rotary encoder detects that the number of revolutions of the predetermined rotation driving device is less than the predetermined number of revolutions, The scheduled material is blocked or loaded; When the second rotary encoder detects that the number of revolutions of the predetermined rotary drive device is greater than the predetermined number of revolutions, the predetermined shaft is idling or the conveying amount of the material is less than the predetermined value, Then the cloud platform controls the detection device to monitor the location of the material pile. Then adjust the relative feeding position of the feeding port.

7. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The cloud platform is provided with a material viscosity compensation module, which is used to adapt to materials of different densities and feed back to the second rotary encoder.

8. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The horizontal rotation drive device, the vertical rotation drive device and the material taking rotation device are respectively provided with vibration sensors, and the vibration sensors judge the conveying condition of the material according to the rotation vibration frequency of the conveying shaft.

9. The unmanned clinker screw conveyor port remote control system according to claim 4, characterized in that: The path of the reclaiming head is based on the historical data to train the clinker fluidity prediction model and optimize the reclaiming path. The prediction model includes a rotation network and a training model, and the prediction model is used to obtain a predetermined material taking position of the inclined surface and a penetration depth of the material taking head.

10. The unmanned clinker screw conveyor port remote control system according to claim 1, characterized in that: The training model is a decision tree model.

Images