A method of sorting material

Abstract

The present disclosure relates to the technical field of ore sorting, and particularly relates to a material sorting method. The method comprises the following steps: determining a relative motion state of a material and a conveying belt according to a mapping relationship between a ray image and a color selection image of the material obtained by a ray device and a color selection camera respectively; if it is determined that the material and the conveying belt are in a relative static state, determining a sorting strategy of the material according to a distance between the ray image, the color selection camera and the ray device, and a running speed of the conveying belt, wherein the sorting strategy comprises a sorting time and a sorting position; if it is determined that the material and the conveying belt are in a relative motion state, determining the sorting strategy according to a motion blur of the material in the color selection image; and performing a sorting operation on the material according to the sorting strategy. Through the present disclosure, the accuracy and efficiency of material sorting can be effectively improved, and more accurate sorting operation can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ore sorting, and particularly relates to a material sorting method. BACKGROUND

[0002] Coal, lithium and silica ore are widely used in current industrial production. However, the ore such as coal, lithium and silica ore usually contains a large amount of gangue and impurities after mining, and needs to be sorted to improve the quality of the ore, reduce transportation costs and reduce environmental pollution. The ore sorting equipment is widely used to meet this demand. Under the premise of resource conservation and environmental protection, efficient and clean use of mineral resources has become a key problem for the survival and development of coal enterprises. For the sorting of ore, the ore is generally transported by a conveying device such as a conveyor belt, and a color selection camera and a radiation device are arranged on the conveying path of the ore to identify and detect the ore, and a sorting device is used to perform a sorting operation. However, the existing ore sorting equipment has certain technical bottlenecks. Since the detected ore may move relative to the conveying device, the outline of the ore collected and detected by the color selection camera and the radiation device is inaccurate, which affects the accuracy of ore identification, resulting in low identification accuracy and incorrect sorting. In addition, since the ore may move relative to the conveying device, the position of the ore deviates too much, the time and position of the sorting operation determined by the outline of the ore collected and detected by the color selection camera and the radiation device are incorrect, resulting in incorrect sorting and missed sorting, thereby reducing the sorting accuracy. SUMMARY

[0003] To overcome the problems in the related art, the exemplary embodiments of the present disclosure provide a material sorting method applied to a material sorting device, including: determining a relative motion state of a material and a conveyor belt according to a radiation image, a color selection image and a mapping relationship between the radiation image and the color selection image of the material obtained by a radiation device and a color selection camera; if it is determined that the material and the conveyor belt are in a relative static state, determining a sorting strategy of the material according to a distance between the radiation image, the color selection camera and the radiation device, and a running speed of the conveyor belt, wherein the sorting strategy includes a sorting time and a sorting position; if it is determined that the material and the conveyor belt are in a relative motion state, determining a sorting strategy according to motion blur of the material in the color selection image; and performing a sorting operation on the material according to the sorting strategy.

[0004] In some embodiments, the determining the sorting strategy according to the motion blur of the material in the color selection image comprises: determining a degree of motion blur of the material in the color selection image; if the degree of motion blur is less than a motion blur threshold, determining a material sorting strategy according to the radiographic image, a distance between the color selection camera and the sorting mechanism, and a running speed of the conveying belt; and if the degree of motion blur is greater than or equal to the motion blur threshold, determining a material sorting time according to the motion blur of the material.

[0005] In some embodiments, the determining the material sorting time according to the motion blur of the material comprises: determining a speed of the material to the radiographic device according to a distance between the radiographic device and the color selection camera, a speed of the material to the color selection camera, and a time of the material moving from the radiographic device to the color selection camera; determining an acceleration of the material according to the speed of the material to the color selection camera, the time of the material moving from the radiographic device to the color selection camera, and the speed of the material to the radiographic device; and determining the material sorting time according to the acceleration of the material, the speed of the material to the color selection camera, and the speed of the material to the radiographic device.

[0006] In some embodiments, the determining the material sorting time according to the acceleration of the material, the speed of the material to the color selection camera, and the speed of the material to the radiographic device comprises: determining a relative motion condition of the material to the conveying belt before the material reaches the sorting device according to the acceleration of the material, the speed of the material to the color selection camera, and the speed of the material to the radiographic device; if the material is relatively static to the conveying belt before the material reaches the sorting device, determining a time required for the material and the conveying belt to reach relative staticity and a time required for the material to move to the sorting device after the material and the conveying belt reach relative staticity as the material sorting time; and if the material has relative motion to the conveying belt before the material reaches the sorting device, determining the material sorting time according to the acceleration of the material, the speed of the material to the color selection camera, a motion speed of the conveying belt, and a distance between the color selection device and the sorting device.

[0007] In some embodiments, determining the material sorting time based on the motion fuzz of the material further includes: determining the actual direction and speed of the material based on the motion fuzz of the material; determining the theoretical direction of the material based on the ray image, the color sorting image, and the mapping relationship between the ray image and the color sorting image; determining the deviation between the actual direction of the material and the theoretical direction of the material; if the deviation between the actual direction of the material and the theoretical direction of the material is less than a motion deviation threshold, then the step of determining the material sorting strategy based on the ray image, the distance between the color sorting camera and the ray device, and the conveyor belt running speed is executed; if the deviation between the actual direction of the material and the theoretical direction of the material is greater than or equal to the motion deviation threshold, then the step of performing the sorting operation on the material based on the sorting strategy is skipped.

[0008] In some embodiments, determining the theoretical motion direction of the material based on the ray image, the color sorting image, and the mapping relationship between the ray image and the color sorting image includes: determining the theoretical contour of the material in the color sorting image based on the ray image and the mapping relationship between the color sorting image and the ray image; determining the vector direction from the centroid of the theoretical contour of the material in the color sorting image to the centroid of the actual contour of the material in the color sorting image as the theoretical motion direction of the material based on the theoretical contour of the material in the color sorting image and the actual contour of the material in the color sorting image; or, determining all contour points of the theoretical contour of the material in the color sorting image based on the theoretical contour of the material in the color sorting image and the actual contour of the material in the color sorting image, and determining the vector direction from all contour points of the theoretical contour of the material in the color sorting image to the actual contour points of the material as the theoretical motion direction of the material.

[0009] In some embodiments, determining the actual direction and speed of the material based on the motion blur of the material includes: determining the blur direction and blur length of the material based on the motion blur of the material, and determining the blur direction as the actual direction of the material's movement; and determining the speed of the material based on the exposure time of the color sorting camera and the blur length.

[0010] In some embodiments, determining the relative motion state between the material and the conveyor belt based on the ray image, color sorting image, and mapping relationship between the ray image and the color sorting image of the material acquired by the ray device and the color sorting camera respectively includes: determining the theoretical position of the color sorting contour of the material on the ray image based on the color sorting image and the mapping relationship between the ray image and the color sorting image, as the theoretical ray contour; and determining the relative motion state between the material and the conveyor belt based on the theoretical ray contour and the actual ray contour in the ray image.

[0011] In some embodiments, determining the relative motion state between the material and the conveyor belt based on the theoretical ray profile and the actual ray profile in the ray image includes: matching the theoretical ray profile with the actual ray profile to determine multiple point pairs; determining the degree of deviation of the material based on the distance between each point pair; if the degree of deviation is less than or equal to a profile deviation threshold, determining that the material and the conveyor belt are in a relatively stationary state; if the degree of deviation is greater than a profile deviation threshold, determining that the material and the conveyor belt are in a relative motion state.

[0012] In some embodiments, determining the degree of deviation of the material based on the distance of each point pair includes: determining the distance between two points in each point pair based on multiple point pairs; excluding abnormal point pairs based on the distance between two points in each point pair, and determining the average, standard deviation, and maximum value of the Euclidean distance of multiple target point pairs; and determining the degree of deviation of the material based on the average, standard deviation, and maximum value of the distance of multiple target point pairs.

[0013] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure.

[0014] This disclosure enables the detection and analysis of the relative motion state of materials by combining X-ray images collected by the X-ray device and color sorting images collected by the color sorting camera. This allows the sorting device to more accurately predict the actual position of the material falling from the conveyor belt and the sorting time, thereby avoiding sorting failures or mis-sorting caused by material position errors, improving sorting accuracy, and avoiding misoperation of the sorting device. This effectively improves the accuracy and efficiency of material sorting and enables more precise sorting operations. Attached Figure Description

[0015] The invention can be better understood by describing exemplary embodiments of the invention in conjunction with the accompanying drawings, in which:

[0016] Figure 1 This is a flowchart illustrating a material sorting method according to an exemplary embodiment of the present disclosure;

[0017] Figure 2 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0018] Figure 3 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0019] Figure 4 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0020] Figure 5This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0021] Figure 6 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0022] Figure 7 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0023] Figure 8 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0024] Figure 9 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure;

[0025] Figure 10 This is a flowchart illustrating a material sorting method according to another exemplary embodiment of the present disclosure. Detailed Implementation

[0026] The following describes specific embodiments of the present invention. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. It should be understood that, in the actual implementation of any embodiment, just as in any engineering or design project, various specific decisions are often made to achieve the developer's specific goals and to meet system-related or business-related constraints, and this can change from one embodiment to another. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this invention, some design, manufacturing, or production modifications based on the technical content disclosed herein are merely conventional technical means and should not be construed as insufficient content of this disclosure.

[0027] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in the patent application description and claims of this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the element or object preceding "comprising" or "including" encompasses the element or object listed following "comprising" or "including" and its equivalents, and do not exclude other elements or objects. The terms "connected" or "linked" and similar terms are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0028] Material sorting equipment is used to identify and sort materials, thereby achieving the classified collection of materials. Materials are typically transported via conveyor belts or other transport mechanisms, with X-ray cameras and color sorting cameras positioned above the conveyor belt to capture X-ray images and color sorting images of the materials, respectively. The sorting equipment can determine the material category based on these images and, using the information from the X-ray and color sorting images, determine the position and time of the material's descent from the conveyor belt, thus determining the position and time at which the sorting device performs the sorting operation. The distance between the X-ray device and the color sorting camera is fixed, and the conveyor belt speed is fixed, thus allowing the determination of the time difference dt between capturing the X-ray image and capturing the color sorting image. A X-ray image is captured at any time t0; the material outline captured in the X-ray image is the X-ray outline. At time t0+dt, the color sorting camera can capture an image of the same material; the material outline in the captured color sorting image is the color sorting outline. Theoretically, if the material remains relatively stationary relative to the conveyor belt, the ray profile and the color sorting profile can correspond to each other. This means that any point P on the material acquired by the ray device at time t0 corresponds to the same point P' acquired by the color sorting camera at time t0+dt. However, the material may undergo relative motion with the conveyor belt, such as acceleration or rotation. This relative motion can cause the profile position of the same material in the ray image and the color sorting image to shift, resulting in a misalignment between the ray profile and the color sorting profile. Consequently, the sorting equipment may deviate in determining the sorting position and time based on the material's ray profile and color sorting profile, leading to errors in material sorting, including incorrect and missed sorting, thus reducing sorting accuracy.

[0029] Based on the above technical issues, such as Figure 1 As shown, this disclosure provides a material sorting method, including steps S110 to S140.

[0030] Step S110: Determine the relative motion state between the material and the conveyor belt based on the ray images, color sorting images, and the mapping relationship between the ray images and color sorting images of the material acquired by the ray device and the color sorting camera, respectively. First, a ray image of the material can be captured by the ray device, and then a color sorting image of the material can be captured by the color sorting camera. The time interval between capturing each ray image and color sorting image between the ray device and the color sorting camera is the same. The ray image includes the ray outline of the material, and the color sorting image includes the color sorting outline of the same material. In addition, the color sorting image may also include information such as the color of the material surface. For the material on the conveyor belt, when it remains relatively stationary with respect to the conveyor belt, a mapping is established between the ray images and the color sorting images. Based on the mapping relationship, the ray outlines in the ray images and the color sorting outlines in the color sorting images should be consistent, and any point on the ray outline and the corresponding outline point on the color sorting outline should be in the same position after mapping, so that the ray outline and the color sorting outline have the same size and pose. When the material is in relative motion with the conveyor belt, its position on the conveyor belt changes due to acceleration from the time it is photographed by the X-ray device until it is photographed by the color sorter; or, the material may rotate, causing a change in its posture on the conveyor belt. If the material and the conveyor belt remain relatively stationary, the sorting device of the material sorting equipment can directly determine the time and position for sorting the material based on information such as the X-ray image, with high accuracy. However, when the material moves relative to the conveyor belt, its position shifts. This means that the material may continuously shift in position and posture as it moves from the color sorter to the sorting device, making it impossible for the sorting device to accurately determine the time and position for sorting based on the X-ray image, leading to reduced sorting accuracy. Therefore, the relative motion state between the material and the conveyor belt can be determined first by using the X-ray image and color sorting image of the material acquired by the X-ray device and color sorter, respectively, as well as the mapping relationship between the X-ray image and the color sorting image. This allows the state and orientation of the material to be determined in subsequent steps, enabling the use of different sorting strategies for materials that move relative to the conveyor belt and materials that remain relatively stationary. This allows the material sorting equipment to obtain more accurate sorting time and sorting position information, thereby improving the accuracy and efficiency of material sorting.

[0031] Step S120: If it is determined that the material and the conveyor belt are in a relatively stationary state, then the material sorting strategy is determined based on the X-ray image, the distance between the color sorter and the X-ray device, and the conveyor belt speed. The sorting strategy includes sorting time and sorting position. When the material and the conveyor belt are in a relatively stationary state, it can be determined that the material and the conveyor belt remain relatively stable and do not move during the process of moving from the X-ray device to the color sorter. Therefore, it can be assumed that the material will also maintain a relatively stable state with the conveyor belt during the subsequent process of moving from the color sorter to the sorting device. Thus, the material sorting strategy can be determined based on the X-ray image of the material, the first distance between the color sorter and the X-ray device, and the conveyor belt speed. The material sorting strategy includes the sorting time for the sorting device to perform the sorting operation and the position where the material will fall from the conveyor belt, i.e., the sorting position where the sorting device performs the sorting operation.

[0032] Step S130: If it is determined that the material and the conveyor belt are in relative motion, a sorting strategy is determined based on the motion blur of the material in the color sorting image. When the material and the conveyor belt are in relative motion, it can be determined that during the process of moving from the X-ray device to the color sorting camera, the material experiences acceleration relative to the conveyor belt, resulting in a difference between the material's moving speed and the conveyor belt's transmission speed, or that the material rotates during transmission. This relative motion also indicates that the material's pose changes relative to the conveyor belt during its movement from the X-ray device to the color sorting camera, making it impossible to directly register the material's color sorting contour with the X-ray contour based on the mapping relationship. This relative motion causes motion blur in the color sorting image captured by the color sorting camera. Furthermore, the change in the material's pose during its movement from the X-ray device to the color sorting camera makes it impossible to directly determine the sorting position and time of the material during its descent from the conveyor belt based on the X-ray image information and the conveyor belt speed. Furthermore, because the material may maintain relative motion with the conveyor belt during its movement from the color sorter to the sorting device, its posture continuously changes. Therefore, it's impossible to directly determine the sorting position and time of the material during its descent from the conveyor belt based solely on the X-ray image information and the conveyor belt speed. Thus, the sorting strategy can be determined based on the motion blur of the material in the color sorting image. Motion blur reflects the direction and speed of the material's relative motion with the conveyor belt. Therefore, determining the sorting strategy based on the motion blur in the color sorting image allows for more accurate determination of the sorting time and position, avoiding incorrect or missed sorting.

[0033] Step S140: Perform a sorting operation on the material according to the sorting strategy. Based on the determined sorting strategy, the material can be sorted using a sorting device. Specifically, the sorting device can be a pusher mechanism including multiple pushers or a spraying mechanism including multiple nozzles. For a pusher mechanism, determining the sorting position of the material determines one or more pushers to perform the sorting operation. For a spraying mechanism, determining the sorting position of the material determines one or more nozzles to perform the sorting operation. Based on the determined sorting strategy, the time and position of the material falling from the conveyor belt can be determined more accurately, enabling the sorting device to respond promptly and accurately, achieving accurate sorting. This effectively avoids sorting errors caused by premature or delayed sorting operations, and also effectively avoids invalid sorting caused by incorrect judgment of the sorting position, resulting in the sorting device failing to push or spray onto the corresponding material, thus effectively improving the accuracy of material sorting.

[0034] This disclosure combines multimodal detection information from X-ray images acquired by an X-ray device and color sorting images acquired by a color sorting camera, and analyzes the relative motion state of the materials. This allows the sorting device to accurately predict the actual falling trajectory and sorting time of the materials, avoiding sorting failures or mis-sorting due to material position errors, thus improving sorting accuracy. Different sorting strategies can be determined and executed based on the different relative motion states of the materials and the conveyor belt, demonstrating good adaptability. For materials that are stationary relative to the conveyor belt, the sorting time and position can be directly determined based on the conveyor belt speed, the distance between the X-ray device and the color sorting camera, and the X-ray image information, ensuring the stability of the sorting operation. For materials that are moving relative to the conveyor belt, motion blur in the color sorting images can be analyzed to infer the displacement, rotation, and other information of the materials, dynamically adjusting the sorting strategy to achieve more accurate sorting. Traditional methods, when the material's motion state is uncertain, are prone to misjudgment leading to premature or delayed sorting, or positional deviations causing the pusher or nozzle to fail to accurately act on the target material. This method can improve sorting efficiency by accurately calculating sorting time and position, avoiding misoperation of the sorting device. This disclosure employs automated image analysis and motion state calculation, eliminating the need for manual adjustment of sorting parameters, reducing human error, and improving the automation level of material sorting equipment, making material sorting more efficient and intelligent.

[0035] In some embodiments, such as Figure 2 As shown, in step 130, the sorting strategy is determined based on the motion blur of the material in the color sorting image, and may also include steps S131 to S133.

[0036] Step S131: Determine the degree of motion blur in the color sorting image. When materials pass through the color sorting camera, they move relative to the conveyor belt, resulting in varying degrees of motion blur in the images captured by the camera. Edge detection, Fourier analysis, and other methods can be used to extract the motion-blurred outline information from the color sorting image, quantifying the motion blur and determining its degree. Motion blur reflects the speed and direction of material movement. Specifically, when materials move relative to the conveyor belt in any direction, the color sorting outline in the image may be blurred in its direction of movement. The actual direction and speed of material movement can be determined based on the direction and length of the motion blur.

[0037] Step S132: If the motion ambiguity is less than the motion ambiguity threshold, the material sorting strategy is determined based on the ray image, the distance between the color sorting camera and the sorting mechanism, and the conveyor belt speed. A motion ambiguity threshold can be preset. When the motion ambiguity is less than the preset threshold, the relative motion between the material and the conveyor belt can be considered relatively slow or basically stable. The relative motion between the material and the conveyor belt at the moment captured by the color sorting camera can be regarded as relatively stationary. Therefore, the sorting time and position of the material can be determined based on the ray contour in the ray image, the distance from the color sorting camera to the sorting device, and the conveyor belt speed. The ray contour of the material can be clearly obtained from the image acquired by the ray device, reflecting the shape, size, and initial position of the material on the conveyor belt. By analyzing these contours using image processing algorithms, the position and edge features of the material in the ray image can be accurately determined. Subsequently, since the relative motion state between the material and the conveyor belt at the moment captured by the color sorting camera is considered to be relatively stationary, it can be determined that during the process of the material moving from the color sorting camera to the sorting device, its moving speed is consistent with the speed of the conveyor belt, and its position and attitude relative to the conveyor belt do not change. Therefore, based on the fixed distance between the color sorting camera and the sorting device, combined with the running speed of the conveyor belt, the expected transmission time of the material from the location of the color sorting camera to the sorting device can be determined as the sorting time. At the same time, the position of the material on the conveyor belt at the moment of the color sorting camera's capture can be determined, thereby accurately determining the falling position of the material at the end of the conveyor belt as the sorting position.

[0038] Step S133: If the motion blur level is greater than or equal to the motion blur threshold, the material sorting time is determined based on the motion blur of the material. When the motion blur level is greater than or equal to the preset motion blur threshold, it can be assumed that at the moment the color sorting camera captures the color sorting image, the material and the conveyor belt are still in relative motion, and this relative motion is relatively intense. This causes the material to maintain relative motion with the conveyor belt as it moves from the color sorting camera location to the sorting device. Therefore, in this case, the speed and orientation of the material continuously change as it moves from the color sorting camera location to the sorting device, making it impossible to determine the sorting time and position based on the fixed distance between the color sorting camera and the sorting device and the conveyor belt's running speed. Since the motion blur in the color sorting image can reflect the direction and speed of the material's movement at the moment the color sorting image is captured, the motion speed and acceleration of the material at the moment the color sorting image is captured can be determined based on the motion blur, thereby determining a more accurate material sorting time.

[0039] The material sorting method provided in this embodiment can accurately distinguish whether materials are relatively stationary with respect to the conveyor belt or exhibit significant relative motion by detecting the degree of motion ambiguity in the color sorting image. This allows for the determination of different sorting strategies, improving the accuracy and reliability of sorting. Quantitative analysis of motion ambiguity using edge detection and Fourier analysis not only determines whether materials are undergoing relative motion but also further identifies their direction, speed, and acceleration, facilitating more precise determination of the sorting time and position. When the degree of motion ambiguity is low, the sorting time and position can be accurately calculated based on the conveyor belt speed and a fixed distance, ensuring efficient and stable sorting. When the degree of motion ambiguity is high, the sorting time can be calculated based on the motion ambiguity information, rather than solely relying on the conveyor belt speed, thus avoiding mis-sorting or missed sorting due to material position deviation and improving the sorting success rate. Through accurate prediction based on motion ambiguity, this method ensures that the sorting operation only applies to the correct materials, thereby reducing ineffective operations and improving equipment lifespan and energy efficiency.

[0040] In some embodiments, such as Figure 3 As shown, step S133, which determines the material sorting time based on the motion fuzziness of the material, also includes steps S1331 to S1333.

[0041] Step S1331: Determine the speed of the material reaching the color sorting camera based on the distance between the X-ray device and the color sorting camera, the speed of the material when it arrives at the color sorting camera, and the time it takes for the material to move from the X-ray device to the color sorting camera. Since motion blur occurs in the color sorting image captured by the color sorting camera, it can be determined that the material is in relative motion at the moment the color sorting camera captures the image. Based on the motion blur, the speed of the material at the moment it arrives at the color sorting camera can be determined, i.e., the speed of the material at the moment the color sorting camera captures the color sorting image. The time interval between the X-ray device acquiring X-ray images and the time interval between the color sorting camera acquiring color sorting images are both preset fixed values. Therefore, the time interval between capturing the X-ray image of the current material and capturing the color sorting image of the current material can be determined based on these time intervals, i.e., the time it takes for the material to move from the X-ray device to the color sorting camera. The distance between the X-ray device and the color sorting camera is a fixed preset value. Therefore, based on the speed of the material when it arrives at the color sorting camera, the distance between the X-ray device and the color sorting camera, and the time it takes for the material to move from the X-ray device to the color sorting camera, the speed of the material when it arrives at the X-ray camera can be calculated, i.e., the speed of the material at the moment the X-ray device captures the image. Specifically, since the method provided in this embodiment is only used to determine the material sorting time, and the sorting time is only related to the parameters of the material along the conveyor belt movement direction, the velocity component V of the material along the conveyor belt movement direction when it reaches the color sorter can be determined according to the following formula based on the distance from the X-ray device to the color sorter, the velocity component of the material along the conveyor belt movement direction when it reaches the color sorter, and the time taken for the material to travel from the X-ray device to the color sorter. X :

[0042]

[0043] Among them, S XC t is the distance from the X-ray device to the color sort camera. XC V is the time it takes for the material to travel from the X-ray device to the color sorter. C This represents the velocity component of the material along the conveyor belt direction when it reaches the color sorter.

[0044] Step S1332: Determine the acceleration of the material based on its speed upon arrival at the color sorting camera, the time it takes for the material to move from the X-ray device to the color sorting camera, and the speed at which the material reaches the X-ray device. The material's acceleration can be the acceleration when it arrives at the color sorting camera, i.e., the acceleration of the material at the moment the color sorting camera acquires the color sorting image. Based on the speed of the material upon arrival at the color sorting camera, the speed at which the material reaches the X-ray device, and the time it takes for the material to move from the X-ray device to the color sorting camera, the acceleration of the material at the moment the color sorting camera acquires the color sorting image can be determined. This allows for subsequent determination of the material's movement speed and sorting time based on the material's acceleration at the moment the color sorting camera acquires the color sorting image. Specifically, since the method provided in this embodiment is only used to determine the material's sorting time, and the sorting time is only related to parameters along the material's movement direction along the conveyor belt, the acceleration of the material along the conveyor belt movement direction can be determined based on the velocity component of the material along the conveyor belt movement direction when it arrives at the color sorting camera, the velocity component of the material along the conveyor belt movement direction when it arrives at the X-ray device, and the time it takes for the material to move from the X-ray device to the color sorting camera. According to the formula: a = (V C -V X ) / t XC The acceleration 'a' of the material along the direction of movement of the conveyor belt can be determined, where V X V represents the velocity component along the conveyor belt direction when the material arrives at the radiation device. C Let t be the velocity component of the material along the conveyor belt direction when it reaches the color sorter. XC The time it takes for the material to travel from the X-ray device to the color sorter.

[0045] Step S1333: Determine the material sorting time based on the material's acceleration, its speed upon reaching the color sorter, and its speed upon reaching the X-ray device. Based on the material's acceleration, its speed upon reaching the X-ray device, and its speed upon reaching the color sorter, the motion parameters of the material during its movement from the color sorter to the sorting device can be determined. Since the material has acceleration along the conveyor belt direction at the moment it is photographed by the color sorter, it can be determined that during the process from the color sorter to the end of the conveyor belt until the sorting device performs the sorting operation, the material and the conveyor belt may maintain relative motion, accelerating relative to the conveyor belt throughout the entire process until it falls. The material may also reach a relatively stationary state with the conveyor belt midway, causing its velocity component along the conveyor belt direction to match the conveyor belt's speed before falling. Specifically, based on the material's acceleration along the conveyor belt direction, its speed along the conveyor belt direction upon reaching the color sorter, and its speed along the conveyor belt direction upon reaching the X-ray device, the sorting time from the color sorter to the end of the conveyor belt until the sorting device performs the sorting operation can be determined.

[0046] The material sorting method provided in this embodiment, by calculating the speed of the material when it arrives at the X-ray device, can more accurately grasp the initial motion state of the material on the conveyor belt. This effectively compensates for errors in the color sorting image caused by shooting angle or lighting conditions, making the calculation of the material's motion parameters more stable and reliable. By calculating the material's acceleration, the movement trend of the material on the conveyor belt can be accurately determined, thereby adjusting the sorting strategy and ensuring the accuracy of the sorting operation. Since the material's motion state continues to change after the color sorting camera, relying solely on the color sorting image may lead to incorrect judgments, thus triggering incorrect sorting operations. By calculating the sorting time, the sorting device performs the sorting action only when the material reaches the appropriate position, reducing ineffective pushing or blowing operations, lowering the equipment's energy consumption and mechanical wear, and improving the long-term stability of the system. This method can effectively reduce mis-sorting caused by material position deviation and improve the response speed of the sorting system.

[0047] In some embodiments, such as Figure 4 As shown, step S1333 determines the material sorting time based on the material's acceleration, its speed upon reaching the color sorting camera, and its speed upon reaching the X-ray device. It also includes steps S13331 to S13333.

[0048] Step S13331: Based on the material's acceleration, its speed upon reaching the color sorter, and its speed upon reaching the X-ray device, determine the relative motion of the material with the conveyor belt before reaching the sorting device. Since the material has acceleration along the conveyor belt's direction of movement when photographed by the color sorter, and the material's movement may experience some losses, causing its speed to gradually decrease, the material eventually reaches a state of relative stillness with the conveyor belt within a certain time or distance, making the material's velocity component along the conveyor belt's direction of movement consistent with the conveyor belt's speed. However, the distance from the color sorter to the sorting device is finite; therefore, the material may be in different motion states upon reaching the sorting device under different circumstances. Specifically, during the process of moving from the color sorter to the end of the conveyor belt until the sorting device performs the sorting operation, the material and the conveyor belt may always maintain a relative motion state, with the material accelerating relative to the conveyor belt throughout the entire process until it falls. Material may also experience wear and tear due to friction with the conveyor belt surface, causing its speed to gradually decrease. This allows the material to reach a state of relative stillness with the conveyor belt midway from the color sorter to the end of the conveyor belt until it is sorted by the sorting device. This ensures that the material's velocity component in the conveyor belt's direction of movement matches the belt's speed, allowing it to fall and be sorted by the sorting device. Specifically, whether the material reaches a state of relative stillness with the conveyor belt before reaching the sorting device can be determined using parameter t1. t1 = (V B -V C) / a, where V C V represents the velocity component of the material along the conveyor belt direction when it reaches the color sorter. B Let be the speed of the conveyor belt, and 'a' be the acceleration of the material along the conveyor belt direction at the moment it is photographed by the color sorting camera. When t1 ≥ 0, it can be assumed that the material and the conveyor belt may reach a relatively stationary state in the direction of the conveyor belt's movement before reaching the sorting device. Specifically, the material may reach a relatively stationary state with the conveyor belt before reaching the sorting device; it may also reach a relatively stationary state with the conveyor belt only at the moment the material reaches the sorting device, or after the material reaches the sorting device. This can be determined based on: A judgment is made. Here, S1 is the distance the material needs to travel in its current state of motion until it reaches a relatively stationary state with the conveyor belt. V C Let S1 be the velocity of the material along the conveyor belt at the moment the color sorting camera captures the image, and α be the acceleration of the material along the conveyor belt at the moment the color sorting camera acquires the sorted image. When S1 < S... CW Under these circumstances, it can be determined that the material reaches velocity V. B When S1 ≥ S, that is, when the material and the conveyor belt reach a relatively stationary state, the material has not yet reached the sorting device. CW Under these circumstances, it can be determined that the material reaches velocity V. B When t1 < 0, it means that the material has reached or passed the sorting device when it reaches a relatively stationary state with the conveyor belt. When t1 < 0, it can be assumed that the velocity component of the material along the conveyor belt's direction of motion cannot reach the conveyor belt's speed before reaching the sorting device, indicating that the material is continuously accelerating relative to the conveyor belt, meaning that the material and the conveyor belt maintain relative motion in the direction of motion. Based on the relative motion between the material and the conveyor belt before reaching the sorting device, different methods can be used to determine the material's sorting time according to different relative motion states. In step S13332, if the material is relatively stationary with the conveyor belt before reaching the sorting device, the time required for the material and the conveyor belt to reach a relatively stationary state, and the time required for the material to move to the sorting device after reaching a relatively stationary state, are determined as the material sorting time. If the material can reach a relatively stationary state before reaching the sorting device, the material sorting time from the color sorter to the sorting device can be divided into two parts. One part is the time required from the start of the material's movement from the color sorter towards the sorting device until the material reaches the same speed as the conveyor belt along its direction of movement; that is, the time required for the material and the conveyor belt to reach a relatively stationary state. The other part is the time required for the material to move to the sorting device after reaching relative stationary with the conveyor belt. Adding these two times together gives the total time required for the material to move from the color sorter to the sorting device, i.e., the material sorting time. Specifically, this can be calculated using the formula... Determined. Wherein, tCW V represents the material sorting time. B V is the speed of the conveyor belt. C S is the speed of the material along the conveyor belt at the moment it is photographed by the color sorting camera. CW denoted as , where is the distance between the color sorter and the sorting device, i.e., the distance the material travels from the color sorter to the sorting device; 'a' is the acceleration of the material along the conveyor belt at the moment the color sorter captures the color sorting image. It is the time required for the material and the conveyor belt to reach a relatively stationary state.

[0049] Step S13333: If the material moves relative to the conveyor belt before reaching the sorting device, the sorting time is determined based on the material's acceleration, its velocity when it reaches the color sorter, and the distance between the color sorter and the sorting device. If the material remains in relative motion with the conveyor belt before reaching the sorting device, the sorting time can be directly determined using the material's acceleration along the conveyor belt's direction of movement, the velocity component along the conveyor belt's direction of movement when it reaches the color sorter, and the distance the material travels from the color sorter to the sorting device. Specifically, this can be achieved using the formula... Determine, where t CW V represents the material sorting time. C Let S be the speed of the material along the conveyor belt at the moment it is photographed by the color sorting camera. CW denoted as , where is the distance between the color sorting camera and the sorting device, i.e., the distance the material travels from the color sorting camera to the sorting device. 'a' represents the acceleration of the material along the conveyor belt at the moment the color sorting camera acquires the color sorting image.

[0050] The material sorting method disclosed herein, by calculating whether the material reaches a relatively stationary state with respect to the conveyor belt before arriving at the sorting device, can more accurately determine the material's motion pattern, thereby optimizing the calculation of sorting time. The material may experience continuous acceleration or eventually reach a stationary state on the conveyor belt. This method can select different calculation methods according to the actual situation, ensuring that the sorting device operates at the most appropriate time. If the material remains in relative motion with the conveyor belt before arriving at the sorting device, it may deviate from the originally expected falling trajectory, causing sorting errors. This method, by accurately calculating the material's acceleration and motion state, allows the sorting device to adjust its actions in a timely manner, reducing mis-sorting or missed sorting. Especially for irregularly shaped or easily rolling materials, this method can better adapt to their complex motion characteristics, improving sorting accuracy. Because this method can dynamically adapt to the motion characteristics of different materials, it can maintain a high sorting accuracy and has better robustness when dealing with materials of different shapes, masses, or surface properties.

[0051] In some embodiments, such asFigure 5 As shown, step S130, which determines the material sorting time based on the motion fuzziness of the material, may also include steps S134 to S138.

[0052] Step S134: Determine the actual direction and speed of the material's movement based on the motion blur. Because the material and conveyor belt are in relative motion at the time the color sorting image is captured, the material's speed is inconsistent with the conveyor belt's speed; the material's speed is greater than the conveyor belt's speed, resulting in motion blur in the color sorting image. Motion blur causes the edges of the color sorting outline in the color sorting image to appear elongated. The actual direction of the material's movement when it is in relative motion with the conveyor belt, as well as the actual speed of the material at the time of color sorting image acquisition, can be determined based on the length and direction of this elongation.

[0053] Step S135: Determine the theoretical direction of material movement based on the X-ray image, the color sorting image, and the mapping relationship between the X-ray image and the color sorting image. Based on the ray contour in the X-ray image, the mapping relationship between the X-ray image and the color sorting image, and the color sorting contour in the color sorting image, the ray contour can be mapped to the color sorting image to determine the theoretical contour of the ray contour in the color sorting image. Based on the deviation between the color sorting contour and the theoretical contour, the theoretical direction of material movement can be determined, i.e., based on the material's speed and direction of movement when it arrives at the X-ray device, and at the moment the color sorting camera captures the material, the theoretical direction of material movement. Since the material's motion state may continuously change during its movement from the X-ray device to the color sorting camera, specifically, the material may rotate during this process, thus causing a change in its actual direction of movement.

[0054] Step S136: Determine the deviation between the actual and theoretical directions of material movement. Based on the determined actual and theoretical directions, the deviation can be recorded as an angle. The angle formed by the actual and theoretical directions of material movement can be defined as the deviation. A movement deviation threshold can be set, and the deviation between the actual and theoretical directions can be compared with this threshold. Different sorting strategies can be adopted based on the magnitude of the deviation.

[0055] Step S137: If the deviation between the actual movement direction of the material and the theoretical movement direction of the material is less than the movement deviation threshold, then execute step S132 to determine the material sorting strategy based on the X-ray image, the distance between the color sorting camera and the X-ray device, and the speed of the conveyor belt.

[0056] When the deviation between the actual and theoretical directions of material movement is less than a threshold, it can be assumed that the overall direction of material movement remains stable during its movement from the X-ray device to the color sorter, with minimal deviations in both direction and speed. In this case, it can be assumed that the direction of material movement from the color sorter image to the sorting device remains consistent with its direction of movement during the movement from the X-ray device to the color sorter. Therefore, a material sorting strategy can be determined based on the X-ray image, the distance from the color sorter to the sorting mechanism, and the conveyor belt speed.

[0057] In step S138, if the deviation between the actual movement direction of the material and its theoretical movement direction is greater than or equal to the movement deviation threshold, step S140 is skipped, and the material is sorted according to the sorting strategy. When the deviation between the actual movement direction of the material and its theoretical movement direction is greater than or equal to the movement deviation threshold, it can be assumed that the overall movement direction and speed of the material deviate significantly during its movement from the X-ray device to the color sorter, or that the material collides with other materials, resulting in a large cumulative error in the movement, making it difficult to accurately confirm the movement information of the material. Therefore, in this case, step S140 can be skipped, and the material is not sorted, thereby avoiding errors in the calculation of sorting time and sorting position due to large errors.

[0058] The material sorting method provided in this embodiment determines the actual direction and speed of material movement by analyzing motion fuzziness, rather than relying solely on theoretical calculations. This allows the sorting system to more accurately adapt to the dynamic changes of materials. During transport, materials may undergo nonlinear movements such as rotation, jumping, and tilting, resulting in significant deviations between their actual and theoretical directions. By setting a motion deviation threshold, the system can identify materials with abnormal motion states and choose whether to perform sorting, avoiding mis-sorting. For materials with small deviations, the system can continue to use standard sorting strategies based on ray images, color sorting camera positions, and conveyor belt speeds to ensure efficient processing. For materials with large deviations, the system can choose to skip sorting to reduce errors. This flexible sorting strategy improves the system's reliability, enabling it to adapt to materials of different types, shapes, and motion states, improving overall sorting accuracy. It also reduces ineffective actions of the sorting device, lowers mechanical wear and energy consumption, and increases sorting efficiency.

[0059] In some embodiments, such as Figure 6 As shown, step S134, which determines the actual direction and speed of the material's movement based on the material's motion fuzziness, may include steps S1341 and S1342.

[0060] Step S1341: Based on the motion blur of the material, determine the blur direction and blur length of the material, and define the blur direction as the actual movement direction of the material. Based on the color-sorted image captured by the color-sorting camera, the features of the motion blur captured in the color-sorting image can be determined. These features can include the blur direction and blur length. The contour information of the material in the color-sorting image, i.e., the color-sorting contour, can be determined using an edge detection algorithm. Since the material undergoes motion blur, the contour of the blurred area generally exhibits an elongated shape; therefore, the direction of the elongated contour of the blurred area is the motion blur direction of the material. Furthermore, based on the captured color-sorted image of the material, a Fourier transform can be performed on the color-sorting image to determine the spectrum of the color-sorting image, thereby performing spectral analysis on the blurred area in the color-sorting image. The blur direction usually corresponds to the direction of enhancement of low-frequency components in the spectrum; therefore, the blur direction of the material can be determined through the spectrum. The length of the blurred area in the color-sorting image can be determined by measurement, and this length can be in pixels. Subsequently, based on the resolution of the color sorting camera and the length of the blurred region in the color sorting image, the length of the blurred region can be converted into an actual distance, which is then used as the blurred length of the material. Simultaneously, the blurred direction of the material in the color sorting image can be determined as the actual direction of material movement. Furthermore, if the color sorting image contains noise or a complex background, it can be processed using denoising techniques such as Gaussian filtering and background segmentation methods such as background subtraction, effectively improving the extraction accuracy of blurred features.

[0061] Step S1342: Determine the material's movement speed based on the exposure time and blur length of the color sorting camera. The blurring of the material's motion in the color sorting image acquired by the color sorting camera is generally related to the material's movement speed and the camera's exposure time. The material's movement speed can be determined based on the blur length. Specifically, the length of the blurred area in the color sorting image can be determined by measurement, and based on the color sorting camera's resolution, this length is converted into an actual distance, which is used as the material's blur length. The material's movement speed can then be determined based on the blur length and the color sorting camera's exposure time. The material's movement speed can be determined using the following formula: v = m / texp. Here, v is the material's movement speed, i.e., the speed at which the material is captured by the color sorting camera, texp is the exposure time of the color sorting camera (a preset fixed parameter), and m is the blur length. Furthermore, since the determination of the material's movement speed may introduce some error, calibration experiments, such as experiments with the movement of a block at a known speed, can be used to calibrate the current system, improving the accuracy of speed estimation.

[0062] The material sorting method provided in this embodiment can effectively improve the accuracy of judging the direction and speed of material movement. Through edge detection algorithms, the elongation direction of the material's outline in the color sorting image can be identified, thereby determining the blurred direction, which is the actual direction of material movement. Fourier transform analysis can further confirm the motion blur direction through the image's spectral characteristics, improving the robustness of direction recognition. Combining denoising and background segmentation algorithms can reduce the impact of noise and complex backgrounds on motion direction judgment, improving direction extraction accuracy. By calculating the exposure time of the color sorting camera and the blur length of the material, the actual movement speed of the material can be accurately determined. Since materials in the production line may have different frictional characteristics, shapes, and weights, their movement state may change over time. This method can dynamically calculate motion parameters at each exposure time of the color sorting camera, enabling the system to adjust the sorting strategy in real time, achieving accurate sorting, reducing the false judgment rate, and significantly improving the accuracy, adaptability, and stability of the sorting system.

[0063] In some embodiments, such as Figure 7 As shown, step S135, which determines the theoretical direction of material movement based on the ray image, the color sorting image, and the mapping relationship between the ray image and the color sorting image, may also include steps S1351, S1352, or steps S1351 and S1353.

[0064] Step S1351: Based on the X-ray image and the mapping relationship between the color sorting image and the X-ray image, determine the theoretical contour of the material in the color sorting image. To determine the theoretical direction of material movement from the X-ray device to the color sorting device, the color sorting image and the theoretical image need to be evaluated within the same dimension. Therefore, methods can be used to map the color sorting contour and the X-ray contour of the material to the same dimension. Specifically, based on the mapping relationship between the X-ray image and the color sorting image, and the X-ray contour of the material in the X-ray image, the X-ray contour can be mapped to the color sorting image. This determines the theoretical position of the X-ray contour in the X-ray image within the color sorting image, assuming the material maintains its motion state at the time of X-ray image acquisition. This allows both the X-ray contour and the color sorting contour to coexist in the color sorting image, facilitating the determination of the theoretical direction of material movement based on the relationship between the X-ray contour and the color sorting contour.

[0065] Step S1352: Based on the theoretical and actual contours of the material in the color sorting image, the vector direction from the centroid of the theoretical contour to the centroid of the actual contour in the color sorting image is determined as the theoretical direction of material movement. After mapping the theoretical contour of the material ray contour in the color sorting image, the centroid positions of the theoretical contour and the color sorting contour can be calculated separately to determine the theoretical direction of material movement. The centroid can be determined by averaging the coordinates of the contour points of the theoretical contour and the color sorting contour. The theoretical centroid can be obtained by weighted averaging of the X and Y coordinates of all pixels within the theoretical contour; the color sorting centroid can be obtained by weighted averaging of the X and Y coordinates of all pixels within the color sorting contour. Subsequently, the vector pointing from the theoretical centroid to the color sorting centroid can be determined, and the direction of this vector can be used to determine the theoretical direction of material movement.

[0066] Step S1353: Based on the theoretical contour of the material in the color sorting image and the actual contour of the material in the color sorting image, determine all contour points of the theoretical contour of the material in the color sorting image. The vector direction of all contour points of the material in the actual contour of the material in the color sorting image is the theoretical direction of material movement. The system can extract the coordinate set of all contour points in the theoretical contour and the coordinate set of all corresponding contour points in the color sorting contour. Using the mapping relationship between the color sorting image and the ray image, the most likely corresponding point in the color sorting contour can be found for each point in the theoretical contour. In some cases, the correspondence between theoretical contour points and color sorting contour points may not be a one-to-one match. Correspondence matching can be achieved through the nearest neighbor algorithm or a shape similarity-based matching algorithm. Subsequently, the system can determine a vector direction for each pair of corresponding points, and perform statistical analysis on all vector directions to determine the vector mean. The direction of this mean vector is taken as the theoretical direction of material movement in the color sorting image.

[0067] The material sorting method provided in this embodiment improves the accuracy of motion direction calculation by unifying the spatial dimensions of ray images and color sorting images. Since the ray images and color sorting images are acquired at different times, the material may have already undergone displacement, rotation, or deformation. Therefore, it is necessary to establish a mapping relationship between the two to ensure that the information is comparable within the same dimension. By mapping the ray contour to the color sorting image, the coordinate mismatch problem caused by directly comparing the ray images and color sorting images is avoided, improving the accuracy of data fusion. This allows the system to more accurately determine the theoretical motion direction of the material, providing more precise motion parameters for subsequent sorting strategies. Furthermore, it improves the reliability of sorting, avoiding missorting due to abnormal material motion trajectories. By optimizing the sorting execution strategy, unnecessary sorting errors are reduced, improving sorting efficiency and accuracy.

[0068] In some embodiments, such as Figure 8As shown, step S110 determines the relative motion state between the material and the conveyor belt based on the X-ray image, color sorting image, and mapping relationship between the X-ray image and the color sorting image of the material obtained by the X-ray device and the color sorting camera, respectively. This step may include steps S111 and S112.

[0069] Step S111: Based on the color sorting image and the mapping relationship between the ray image and the color sorting image, determine the theoretical position of the material's color sorting contour on the ray image, which is then used as the theoretical ray contour. In determining the relative motion state between the material and the conveyor belt based on the color sorting image and the ray image, it is necessary to evaluate the color sorting image and the theoretical image within the same dimension. Therefore, methods can be used to map the material's color sorting contour and the ray contour to the same dimension. Specifically, based on the mapping relationship between the ray image and the color sorting image, and the color sorting contour of the material in the color sorting image, the color sorting contour can be mapped to the ray image, thereby determining the theoretical position of the material's color sorting contour in the ray image, assuming the material maintains its motion state at the time of color sorting image acquisition, which is then used as the theoretical ray contour.

[0070] Step S112: Determine the relative motion state between the material and the conveyor belt based on the theoretical ray profile and the actual ray profile in the ray image. The theoretical and actual ray profiles can be compared, and the degree of difference between them determines the relative motion state. Since the material may move or rotate in any direction relative to the conveyor belt during its movement, the deviation between the theoretical and actual ray profiles may include positional and rotational deviations. The relative motion state between the material and the conveyor belt can be determined based on the deviation between the theoretical and actual ray profiles. If the theoretical and actual ray profiles essentially coincide, it indicates that there is no significant relative motion between the material and the conveyor belt between the ray image acquisition and the color sorting image acquisition, and the material can be considered stable. If there is a significant offset between the theoretical and actual ray profiles, it indicates that there is relative motion between the material and the conveyor belt.

[0071] The material sorting method provided in this embodiment can map material contours under different imaging mechanisms to the same coordinate space, avoiding error accumulation caused by coordinate deviation. It uses the contour information of the color sorting image to determine the theoretical position of the material in the ray image. By comparing the theoretical and actual ray contours, the motion state of the material relative to the conveyor belt can be accurately determined, providing more reliable data support for subsequent analysis. By comparing the theoretical and actual ray contours, the degree of material offset can be quantified, improving the accuracy of judging the material's motion state. This ensures that the sorting device can accurately predict the trajectory of the material reaching the sorting position, reducing the missorting rate and improving overall sorting efficiency and accuracy.

[0072] In some embodiments, such asFigure 9 As shown, step S112, which determines the relative motion state between the material and the conveyor belt based on the theoretical ray profile and the actual ray profile in the ray image, may include steps S1121 to S1124.

[0073] Step S1121 matches the theoretical ray contour with the actual ray contour to determine multiple point pairs. This can be done by matching the theoretical and actual contours based on the mapping relationship between the ray image and the color-sorted image, ensuring that each contour point of the theoretical ray contour is matched one-to-one with each contour point of the actual ray contour, thus obtaining multiple point pairs. The contour point matching method can be: nearest neighbor matching, where for each point on the theoretical ray contour, the closest point in the actual ray contour is found as the matching point. Alternatively, an iterative nearest point algorithm can be used to more accurately match the contour points of both the actual and theoretical ray contours.

[0074] Step S1122 determines the degree of material deviation based on the distance between each pair of points. After completing the point pair matching, the spatial deviation between each pair of points in the theoretical ray profile and the actual ray profile can be calculated, i.e., the displacement of the material in different images. If the material's motion on the conveyor belt remains stable, the theoretical ray profile and the actual ray profile should highly coincide, and the distance between corresponding point pairs should be close to zero; however, if the material undergoes relative motion such as slippage, rotation, or jumping on the conveyor belt, the distance between these point pairs will increase significantly. By statistically analyzing the distances of all point pairs, the degree of material deviation can be determined, facilitating subsequent and further determination of whether the material remains relatively stationary with respect to the conveyor belt.

[0075] Step S1123: If the deviation is less than or equal to the contour deviation threshold, then the material and the conveyor belt are determined to be in a relatively stationary state. A contour deviation threshold can be preset to represent the range of minor vibrations that may occur in the material under normal conveyor belt operation. When the deviations of multiple point pairs are all within this threshold range, it indicates that the material's movement is basically consistent with the conveyor belt, and no significant slippage or rotation has occurred. At this point, the material and the conveyor belt can be considered to be in a relatively stationary state, meaning the material remains stable throughout the entire transmission process, and its arrival time and position at the sorting device can be directly calculated based on the conveyor belt's operating speed. In this state, the sorting equipment can complete material sorting according to a predetermined trajectory without additional motion compensation calculations, thereby improving sorting accuracy and response speed.

[0076] If the deviation in step S1124 is greater than the contour deviation threshold, it is determined that the material and the conveyor belt are in relative motion. If the material's deviation exceeds the set contour deviation threshold, it indicates that the material has undergone significant displacement or rotation during its movement from the X-ray device to the color sorting camera, suggesting that the material is in motion relative to the conveyor belt. In this state, directly calculating the material's sorting time and position based on the conveyor belt speed may lead to significant errors; therefore, it is necessary to further determine its actual motion trajectory based on the material's motion fuzzy information.

[0077] The material sorting method provided in this embodiment improves matching accuracy by comparing the theoretical and actual ray profiles to determine corresponding point pairs, avoiding erroneous matching caused by rotation or noise, thereby enhancing the accuracy of determining the material's motion state. By determining the distance between point pairs to calculate the ray profile offset, the degree of material deviation can be accurately determined, and the relative motion of the material can be precisely analyzed. By comparing the degree of material deviation with a deviation threshold, the material's motion state is determined, effectively distinguishing between stable and unstable materials—that is, materials that remain relatively stationary with the conveyor belt and materials that move relative to the conveyor belt. Different sorting strategies are determined based on the different relative motion states of the material and the conveyor belt, reducing misjudgments, optimizing the sorting process, improving sorting precision and accuracy, and reducing resource waste caused by incorrect sorting.

[0078] In some embodiments, such as Figure 10 As shown, step S1122; determining the degree of material deviation based on the distance of each point pair may include steps S11221 to S11223.

[0079] Step S11221: Determine the distance between the two points in each point pair based on multiple point pairs. After establishing a mapping relationship between the ray image and the color sorting image, match the theoretical ray profile with the actual ray profile, selecting multiple point pairs. Each point pair consists of a point on the theoretical ray profile and a corresponding point on the actual ray profile. In this step, the distance between the two points in these point pairs can be calculated, i.e., the degree of offset between the theoretical position of each point on the material profile in the theoretical ray profile and its actual position in the actual profile. This distance can intuitively reflect the positional change of the material at the time of shooting by the color sorting camera relative to the time of shooting by the ray device, providing more accurate information for subsequent judgment of the material's movement state.

[0080] Step S11222: Based on the distance between the two points in each point pair, eliminate abnormal point pairs and determine the average, standard deviation, and maximum value of the Euclidean distance for multiple target point pairs. Since abnormal point pairs may exist during the matching process, such as incorrect matching pairs caused by noise, lighting changes, or image edge errors, it is necessary to remove abnormal point pairs. Specifically, statistical methods can be used to eliminate point pairs with abnormally large distances. The distance distribution of all point pairs can be calculated, and extreme offset points exceeding a certain threshold can be removed. Alternatively, median filtering or anomaly detection methods based on standard deviation can be used to ensure that the selected point pairs represent the overall movement trend of the material. After eliminating abnormal point pairs, the average, standard deviation, and maximum value of the Euclidean distance can be calculated based on the remaining target point pairs. The average distance reflects the degree of overall material offset, i.e., the overall trend of the material's relative movement on the conveyor belt. The standard deviation reflects the stability of the material's movement; a large standard deviation indicates that the material's movement is relatively uneven, possibly involving rotation or irregular sliding. The maximum value can be used to determine whether there is a large local shift. For example, if one end of the material slides far while the other end remains relatively stable, it may indicate that the material has flipped or tilted.

[0081] Step S11223: Determine the degree of material deviation based on the average distance, standard deviation, and maximum value of multiple target point pairs. By using the determined average distance, standard deviation, and maximum value of the target point pairs, the degree of material deviation can be quantified, providing more accurate data support for subsequent sorting strategies. Specifically, if the average distance of multiple target point pairs is close to zero, the standard deviation is small, and the maximum value is also small, it can be determined that the material remains basically stable during transmission and is in a relatively stationary state with the conveyor belt. If the average distance of multiple target point pairs is large, the standard deviation is moderate, and the maximum value does not exceed a certain range, it can be determined that the material has slipped overall but still maintains a certain degree of stability. If the standard deviation of the distance of multiple target point pairs is large, and the maximum value is much larger than the average value, it may indicate that the material has rotated or rolled, resulting in significant differences in the degree of deviation at different locations.

[0082] According to the material sorting method provided in this embodiment, by calculating the distance of each point pair, the displacement of the material can be accurately calculated, intuitively reflecting the movement of the material relative to the conveyor belt. Simultaneously, the offset information of each point can be quantified, which helps in further analyzing the overall motion state. By eliminating abnormal point pairs, the reliability of matching point pairs can be improved, avoiding interference from abnormal data on the results. After obtaining the statistical parameters of the target point pairs, threshold rules can be set to determine the offset of the material relative to the conveyor belt, making the judgment of the relative motion state of the material and the conveyor belt more accurate. This improves the accuracy and efficiency of subsequent sorting strategy determination, thereby improving the efficiency and accuracy of material sorting.

[0083] This application uses specific terms to describe embodiments of the application. Terms such as "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Certain features, structures, or characteristics in one or more embodiments of the application may be appropriately combined.

[0084] In the context of this application, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0085] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the present application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0086] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the embodiments of this application.

Claims

1. A material sorting method applied to a material sorting device, comprising: determining a relative motion state of a material and a conveyor belt according to a mapping relationship between a radiographic image and a color image of the material obtained by a radiographic device and a color camera respectively; if it is determined that the material and the conveyor belt are in a relative static state, determining a sorting strategy of the material according to a distance between the radiographic image, the color camera and the radiographic device, and a running speed of the conveyor belt, wherein the sorting strategy comprises a sorting time and a sorting position; if it is determined that the material and the conveyor belt are in a relative motion state, determining a sorting strategy according to a motion blur of the material in the color image; performing a sorting operation on the material according to the sorting strategy; wherein the determining of the sorting strategy according to the motion blur of the material in the color image comprises: determining a degree of motion blur of the material in the color image; if the degree of motion blur is less than a motion blur threshold, determining a material sorting strategy according to a distance between the radiographic image, the color camera and a sorting mechanism, and a running speed of the conveyor belt; if the degree of motion blur is greater than or equal to the motion blur threshold, determining a material sorting time according to the motion blur of the material; wherein the determining of the material sorting time according to the motion blur of the material comprises: determining a speed of the material when reaching the radiographic device according to a distance between the radiographic device and the color camera, a speed of the material when reaching the color camera, and a time of moving the material from the radiographic device to the color camera; determining an acceleration of the material according to the speed of the material when reaching the color camera, the time of moving the material from the radiographic device to the color camera, and the speed of the material when reaching the radiographic device; determining a material sorting time according to the acceleration of the material, the speed of the material when reaching the color camera, and the speed of the material when reaching the radiographic device.

2. The method of claim 1, wherein, the determining of the material sorting time according to the acceleration of the material, the speed of the material when reaching the color camera, and the speed of the material when reaching the radiographic device comprises: determining a relative motion state of the material and the conveyor belt before the material reaches a sorting device according to the acceleration of the material, the speed of the material when reaching the color camera, and the speed of the material when reaching the radiographic device; if the material and the conveyor belt are relatively static before the material reaches the sorting device, determining a time required for the material and the conveyor belt to reach a relative static state and a time required for the material and the conveyor belt to move to the sorting device after reaching the relative static state as the material sorting time; if the material and the conveyor belt are in relative motion before the material reaches the sorting device, determining a sorting time of the material according to the acceleration of the material, the speed of the material when reaching the color camera, a motion speed of the conveyor belt, and a distance between the color camera and the sorting device.

3. The method of claim 1, wherein, the determining of the material sorting time according to the motion blur of the material further comprises: determining an actual motion direction and a motion speed of the material according to the motion blur of the material. determining a theoretical motion direction of the material according to the radiographic image, the color selection image, and a mapping relationship between the radiographic image and the color selection image; determining a deviation between an actual motion direction of the material and the theoretical motion direction of the material; if the deviation between the actual motion direction of the material and the theoretical motion direction of the material is less than a motion deviation threshold, performing the determining of the material sorting strategy according to the radiographic image, a distance between the color selection camera and the radiographic device, and a running speed of the conveying belt; if the deviation between the actual motion direction of the material and the theoretical motion direction of the material is greater than or equal to the motion deviation threshold, skipping the performing of the sorting operation on the material according to the sorting strategy.

4. The method of claim 3, wherein, The determining of the theoretical motion direction of the material according to the radiographic image, the color selection image, and the mapping relationship between the radiographic image and the color selection image comprises: determining a theoretical contour of the material in the color selection image according to the radiographic image and the mapping relationship between the color selection image and the radiographic image; determining that a vector direction from a centroid of the theoretical contour of the material in the color selection image to a centroid of an actual contour of the material in the color selection image is the theoretical motion direction of the material according to the theoretical contour of the material in the color selection image and the actual contour of the material in the color selection image; or determining that a vector direction from all contour points of the theoretical contour of the material in the color selection image to all contour points of the actual contour of the material in the color selection image is the theoretical motion direction of the material according to the theoretical contour of the material in the color selection image and the actual contour of the material in the color selection image.

5. The method of claim 3, wherein, The determining of the actual motion direction and the motion speed of the material according to the motion blur of the material comprises: determining a blur direction and a blur length of the material according to the motion blur of the material, and determining the blur direction as the actual motion direction of the material; determining the motion speed of the material according to an exposure time of the color selection camera and the blur length.

6. The method of material sorting of claim 1, wherein, The determining of the relative motion state of the material and the conveying belt according to the radiographic image, the color selection image, and the mapping relationship between the radiographic image and the color selection image of the material acquired by the radiographic device and the color selection camera respectively comprises: determining a theoretical position of a color selection contour of the material on the radiographic image as a theoretical radiographic contour according to the color selection image and the mapping relationship between the radiographic image and the color selection image; determining the relative motion state of the material and the conveying belt according to the theoretical radiographic contour and an actual radiographic contour in the radiographic image.

7. The method of sorting material of claim 6, wherein, The determining of the relative motion state of the material and the conveying belt according to the theoretical radiographic contour and the actual radiographic contour in the radiographic image comprises: matching the theoretical radiographic contour and the actual radiographic contour to determine a plurality of point pairs; determining a deviation degree of the material according to a distance of each point pair; if the deviation degree is less than or equal to a contour deviation threshold, determining that the material and the conveying belt are in a relative static state; if the deviation degree is greater than the contour deviation threshold, determining that the material and the conveying belt are in a relative motion state.

8. The method of sorting material of claim 7, wherein, The determining of the deviation degree of the material according to the distance of each point pair comprises: According to a plurality of point pairs, determine the distance between two points of each point pair; According to the distance between two points of each point pair, exclude abnormal point pairs, determine the average value, standard deviation, maximum value of the Euclidean distance of a plurality of target point pairs; According to the average value, standard deviation, maximum value of the distance of a plurality of target point pairs, determine the deviation degree of the material.

Images