Granular composition detection system with automatic weighing and particle size detection functions

Abstract

The utility model discloses a grain composition detection system with automatic weighing and grain size detection functions, which comprises a binocular vision grain size identification device, a rockfill grain weighing platform and a rotary discharging platform, and a camera of the binocular vision grain size identification device is over against the rockfill grain weighing platform. A built-in weighing system is fixedly arranged in the middle of the interior of the rockfill particle weighing platform, the rockfill particle weighing platform is connected with the rotary discharging platform through a transfer bridge, and discharging platform bottom trundles are arranged at the bottom of the rotary discharging platform. According to the utility model, an automatic method is adopted to replace a step of manual screening and weighing in rockfill grading detection, the detection process of the grain grading detection system realizes the detection automation, and the operation time and the labor cost are greatly reduced; the grading calculation method is optimized, the error generated by predicting the rockfill quality through image recognition is corrected, and the grading detection precision is improved. Meanwhile, the method is widely applied to the field of material transportation and detection and can be popularized on a large scale.

Description

Technical Field

[0001] The utility model relates to a particle gradation detection system with automatic weighing and particle diameter detection functions, belonging to the technical field of particle gradation detection. Background Art

[0002] When building a rockfill dam, the gradation of rockfill particles is an important indicator of the quality of the rockfill body. Good gradation means that the rockfill body is relatively dense, and the tiny gaps can be filled as much as possible, which means that there will be less settlement and leakage, and better load-bearing capacity.

[0003] During the filling process of a rockfill dam, the dam materials are repeatedly rolled to break and compact them again, which results in a certain difference in gradation from before filling. To determine the compaction quality of the rockfill materials in a certain area of ​​the dam surface, the compacted particles need to be excavated and taken out for gradation testing. Therefore, the test pit water filling method required by the specification is often used for testing in engineering.

[0004] In recent years, with the development of non-destructive testing technology, nuclear density meters, hammer impact methods and other technologies have also been used in the detection of rockfill compaction, but the detection effect is not stable. At the same time, the rockfill image detection technology combined with machine vision has a relatively good performance in gradation prediction, but in actual application, there are problems such as large environmental restrictions on operation and low prediction accuracy.

[0005] Therefore, how to ensure the accuracy of prediction and automation capabilities while conducting batch testing of rockfill particles is the focus of subsequent research. Utility Model Content

[0006] Purpose of the utility model: The purpose of the utility model is to provide a particle grading detection system that can automatically weigh and detect particle sizes of rockfill particles in batches.

[0007] Technical solution: The utility model is a particle grading detection system with automatic weighing and particle size detection functions, comprising a binocular vision particle size recognition device, a rockfill particle weighing platform and a rotating discharging platform. The camera of the binocular vision particle size recognition device faces the rockfill particle weighing platform. A built-in weighing system is fixedly arranged in the middle part of the rockfill particle weighing platform. The connecting part of the rockfill particle weighing platform and the rotating discharging platform is connected through a transfer bridge.

[0008] Furthermore, casters are provided at the bottom of the rotating discharging platform.

[0009] Furthermore, the casters at the bottom of the discharging platform include a support rod, the support rod is fixed to the bottom of the rotating discharging platform, and a universal caster is installed at the bottom of the support rod. The universal caster can move 360 ​​degrees in the horizontal direction and provide support and follower functions together with the support rod when the rotating discharging platform rotates.

[0010] Furthermore, the universal caster is provided with a direction lock for fixing horizontal rotation and a brake lock for braking.

[0011] Furthermore, the binocular vision particle size identification device includes a group of binocular vision cameras, a supporting device and a lighting device, wherein the binocular vision camera is installed on the top of the supporting device, and the lighting device is installed directly above the shooting area of ​​the binocular vision camera and fixed on the supporting device.

[0012] Furthermore, the cameras of the two binocular vision cameras are placed symmetrically, the shooting area is a rectangular area of ​​800×800 mm, the particle size recognition area is a rectangular area of ​​600×600 mm in the middle of the rockfill particle weighing platform, and the particle size recognition area is located in the middle of the shooting area.

[0013] Furthermore, the supporting device is a tripod, and the lighting device is a 20W LED perforated backlight.

[0014] Furthermore, the main body of the rockfill particle weighing platform is a horizontally placed weighing platform, the weighing platform is connected to the rotary discharging platform through a transfer bridge, conveyor belts are arranged outside the weighing platform and the rotary discharging platform, and a weighing system is arranged inside the weighing platform.

[0015] The conveyor belt is used to transport rockfill particles in batches for continuous grading testing, and automatically discharges the particles through the transfer bridge and the rotating discharge platform. It also serves as the shooting base for the binocular vision camera (i.e., the binocular vision camera shooting area is located above the rockfill particle weighing platform).

[0016] Furthermore, the weighing range of the weighing system is the total mass of all materials on the weighing platform, the measuring range is 0-200kg, and the accuracy is above 0.001kg.

[0017] Furthermore, the transfer bridge is a flexible connection structure, including two flexible telescopic belts, which are fixed on both sides between the rockfill particle weighing platform and the rotating discharging platform, and the flexible telescopic belts can be extended and retracted according to the rotation of the rotating discharging platform.

[0018] Furthermore, the flexible telescopic belt is made of rubber, so that the rotating discharging platform rotates with the rear end of the rockfill particle weighing platform as the rotation center.

[0019] Furthermore, the discharging platform can rotate to both sides within 40°

[0020] Furthermore, the total mass of the rockfill particles obtained by the weighing system and the image data obtained by the binocular vision particle size recognition device are transmitted to the computing terminal and the operator's mobile phone visualization interface via Wifi.

[0021] Furthermore, the computing terminal is used to calculate and generate a grading curve of rockfill particles, and the result information obtained by the particle size detection system and the weighing platform is transmitted to the computing terminal and the operator's mobile phone visualization interface via the built-in WiFi.

[0022] Furthermore, the particle grading detection system with automatic weighing and particle size detection functions has a built-in high-precision grading calculation method based on mass error correction. The total mass of rockfill particles in batches is used as a control indicator to correct the mass of rockfill particles predicted by two-dimensional images to balance the error between the predicted total mass and the actual total mass.

[0023] Beneficial effects: Compared with the prior art, the utility model has the following advantages:

[0024] The particle grading detection system with automatic weighing and particle size detection functions provided by the utility model adopts an automatic method to replace the manual screening and weighing steps in the rockfill grading detection, and proposes a high-precision grading calculation method based on this system. Compared with traditional manual operation, the particle grading detection system realizes the automation of the detection process, greatly reducing the operation time and labor cost; optimizes the grading calculation method, corrects the error caused by image recognition prediction of rockfill quality, and improves the grading detection accuracy. At the same time, the method is widely applicable to the field of material transportation and detection, and can be promoted on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The overall schematic diagram of the particle grading detection system for rockfill dams

[0026] Figure 2 Schematic diagram of the rotating discharging platform

[0027] Figure 3 Detailed diagram of the transfer bridge

[0028] Figure 4 Schematic diagram of flexible structure DETAILED DESCRIPTION

[0029] The technical solution of the utility model is further described below in conjunction with the accompanying drawings.

[0030] like Figure 1As shown, the utility model discloses a particle grading detection system with automatic weighing and particle size detection functions, comprising a binocular vision particle size recognition device 1, a rockfill particle weighing platform 2 and a rotating discharging platform 5. The camera of the binocular vision particle size recognition device 1 faces the rockfill particle weighing platform 2. A built-in weighing system 3 is fixedly arranged in the middle part of the rockfill particle weighing platform 2. The connecting part of the rockfill particle weighing platform 2 and the rotating discharging platform 5 is connected through a transfer bridge 4. The bottom of the rotating discharging platform 5 is provided with a discharging platform bottom caster 6.

[0031] The binocular vision particle size recognition device 1 is composed of a group of binocular vision cameras 101 and its supporting device 102 and an illuminating device 103. The binocular vision camera 101 is installed on the top of the supporting device 102. The cameras of the two binocular vision cameras 101 are symmetrically placed. The shooting area is a rectangular area of ​​800×800 mm. The particle size recognition area is a rectangular area of ​​600×600 mm in the middle position of the rockfill particle weighing platform 2. The particle size recognition area is located in the middle of the shooting area. The illuminating device 103 is a 20W LED perforated backlight, which is installed directly above the shooting area and fixed on the supporting device 102. The supporting device 102 of this embodiment adopts a tripod.

[0032] The main body of the rockfill particle weighing platform 2 is a horizontally placed weighing platform, which is connected to the rotating discharging platform 5 through a transfer bridge 4. Conveyor belts are arranged outside the weighing platform and the rotating discharging platform 5. The conveyor belts are used to transport the rockfill particles in batches for continuous grading detection, and automatically discharge the particles through the transfer bridge 4 and the rotating discharging platform 5. The conveyor belts also serve as a shooting base plate for the binocular vision camera 101 (i.e., the shooting area of ​​the binocular vision camera 101 is located above the rockfill particle weighing platform 2). A weighing system 3 is arranged inside the weighing platform.

[0033] The weighing system 3 is built inside the rockfill particle weighing platform 2, and its weighing range is the total mass of all materials on the weighing platform, with a range of 0-200kg and an accuracy of 0.001kg;

[0034] like Figure 2-4As shown, the transfer bridge 4 is the connection part between the rotating discharging platform 5 and the rock pile particle weighing platform 2. The transfer bridge 4 is a flexible connection structure, including two flexible telescopic belts. The two telescopic belts are fixed on both sides between the rock pile particle weighing platform 2 and the rotating discharging platform 5. The flexible telescopic belts can be extended and retracted according to the rotation of the rotating discharging platform 5. The flexible telescopic belts are made of rubber, so that the rotating discharging platform 5 rotates with the rear end of the rock pile particle weighing platform 2 as the rotation center, and the maximum rotation angle of the rotating discharging platform 5 to both sides is 40°. When the rotating discharging platform 5 rotates to one side, the inner telescopic belt is compressed and the outer telescopic belt is stretched, and the conveyor belt blades at the transfer bridge 4 overlap up and down, so that the rotating discharging platform 5 rotates with the rear end of the rock pile particle weighing platform 2 as the rotation center; the rotating discharging platform 5 can rotate with the rear end of the rock pile particle weighing platform 2 as the rotation center and lift the particles to a certain height. When the amount of rock pile particles detected is large or long-term continuous detection is required, it can prevent the accumulation of rock pile particles (such as Figure 2 shown).

[0035] A discharge platform bottom caster 6 is fixedly provided at the bottom center of the rotating discharge platform 5, and the discharge platform bottom caster 6 is composed of a support rod 601 and a universal caster 602. The support rod 601 is fixed at the bottom center of the rotating discharge platform 5, and the universal caster 602 is installed at the bottom of the support rod 601. The universal caster 602 can move 360° in the horizontal direction, and provides support and follower functions together with the support rod 601 when the rotating discharge platform 5 rotates. At the same time, the universal caster 602 is provided with a direction lock for fixing horizontal rotation and a brake lock for braking.

[0036] The working process of the particle grading detection system capable of automatically weighing and detecting the particle size of rockfill particles in batches according to the utility model is as follows:

[0037] Firstly, after the in-situ excavation, the rockfill particles are transferred to the head end of the rockfill particle weighing platform 2 in batches, and the number of particles put into the test each time is controlled to ensure that all the particles fall into the 600×600mm rectangular area at the head end of the rockfill particle weighing platform 2. The conveyor belt is operated to the shooting area of ​​the binocular vision particle size recognition device 1. When there are particles only in the 600×600mm rectangular area on the weighing platform within the 800×800mm rectangular area, the conveyor belt is paused. After the system is stabilized after 3s of static standing, the binocular vision particle size recognition device 1 obtains image data and total mass information. The conveyor belt is operated to transport this batch of rockfill particles to the rotating discharging platform 5 via the transfer bridge 4, and the rockfill particles are stacked to the designated position via the rotating discharging platform 5. The rockfill particles can fall to the far ground after being lifted by the rotating discharging platform 5. If the rockfill particles are over-accumulated, the direction lock and the brake lock of the casters 6 at the bottom of the discharging platform can be opened, and the transfer bridge 4 can be rotated to adjust the discharging position of the rotating discharging platform 5. After the mass returns to zero, the above operation is repeated to detect the information of the next batch of rockfill particles. The total mass and image data of the acquired rockfill particles are transmitted to the computing terminal and the operator's mobile phone visualization interface via Wifi.

[0038] After the data is integrated, the computing terminal performs preprocessing on the acquired rockfill particle image data → image segmentation → feature extraction → morphology prediction. By extracting the features of the two-dimensional image of the rockfill particles, the rockfill particle size can be measured by the second longest side of the smallest hexahedron of the particle, and the relationship from the two-dimensional contour to the three-dimensional volume is established as follows (1):

[0039]

[0040] In formula (1): V is the volume of rockfill particles, m 3 ;

[0041] a——long side of rockfill particle, m;

[0042] b——second longest side of rockfill particle (i.e. particle size), m;

[0043] FL——Flatness of rockfill particles.

[0044] The mass proportion of rockfill particles in each particle size group can be calculated by the following formula (2):

[0045]

[0046] In formula (2): G is the mass proportion of rockfill particles in the particle size group;

[0047] m i ——The predicted mass of a rockfill particle in this particle size group, kg;

[0048] n——the number of rockfill particles in this size group;

[0049] N is the total number of rockfill particles.

[0050] Based on the total mass M of the batches of particles obtained by the weighing system, the difference between the predicted total mass and the actual total mass can be calculated by the following formula:

[0051]

[0052] Where: δ is the difference between the total mass of the rockfill particles obtained by weighing and the total mass of the predicted rockfill particles, kg;

[0053] M is the total mass of rockfill particles measured by the weighing system, kg;

[0054] N——the total number of particles in this batch;

[0055] m i ——is the predicted mass of each rockfill particle, kg.

[0056] The error δ is distributed to all particles in this batch according to the error weight of each particle (the weight is positively correlated with the particle size of the rockfill particle). The calculation formula is as follows:

[0057]

[0058] Where: i ——The prediction error assigned to the rockfill particle, which is positively correlated with the particle size of the rockfill particle, kg.

[0059] Therefore, the corrected mass proportion of rockfill particles in each particle size group can be calculated by the following formula (4):

[0060]

[0061] In formula (4): G′ is the mass proportion of particles in the particle size group after error correction;

[0062] m i ——The calculated mass of a particle in this particle size group, kg;

[0063] M——total mass measured by the weighing system, kg;

[0064] δ i ——Correction error of the particle, kg.

[0065] The grading curve of rockfill particles can be obtained by accumulating, taking points and drawing according to the mass proportion of rockfill particles in each particle size group.

Claims

1. A particle grading detection system with automatic weighing and particle size detection functions, characterized in that: The invention comprises a binocular vision particle size recognition device (1), a rock pile particle weighing platform (2) and a rotary discharging platform (5), wherein a camera of the binocular vision particle size recognition device (1) faces the rock pile particle weighing platform (2), a built-in weighing system (3) is fixedly arranged at the middle part of the rock pile particle weighing platform (2), and the connecting part of the rock pile particle weighing platform (2) and the rotary discharging platform (5) is connected via a transfer bridge (4).

2. The particle grading detection system with automatic weighing and particle size detection functions according to claim 1 is characterized in that: The bottom of the rotating discharging platform (5) is provided with a discharging platform bottom caster (6).

3. The particle grading detection system with automatic weighing and particle size detection functions according to claim 1 is characterized in that: The caster (6) at the bottom of the discharging platform comprises a support rod (601), the support rod (601) is fixed to the bottom of the rotating discharging platform (5), and a universal caster (602) is installed at the bottom of the support rod (601).

4. The particle grading detection system with automatic weighing and particle size detection functions according to any one of claims 1 to 3, characterized in that: The binocular vision particle size identification device (1) comprises a group of binocular vision cameras (101), a support device (102) and an illumination device (103); the binocular vision camera (101) is installed on the top of the support device (102); the illumination device (103) is installed just above the shooting area of ​​the binocular vision camera (101) and is fixed on the support device (102).

5. The particle grading detection system with automatic weighing and particle size detection functions according to claim 4 is characterized in that: The cameras of the two binocular vision cameras (101) are symmetrically placed, the shooting area is a rectangular area of ​​800×800 mm, the particle size identification area is a rectangular area of ​​600×600 mm in the middle of the rockfill particle weighing platform (2), and the particle size identification area is located in the middle of the shooting area.

6. The particle grading detection system with automatic weighing and particle size detection functions according to claim 4 is characterized in that: The supporting device (102) is a tripod, and the lighting device (103) is a 20W LED perforated backlight.

7. The particle gradation detection system with automatic weighing and particle size detection functions according to any one of claims 1 to 3, characterized in that: The main body of the rockfill particle weighing platform (2) is a horizontally placed weighing platform, which is connected to a rotary discharging platform (5) via a transfer bridge (4), and conveyor belts are arranged outside the weighing platform and the rotary discharging platform (5), and a weighing system (3) is arranged inside the weighing platform.

8. The particle gradation detection system with automatic weighing and particle size detection functions according to any one of claims 1 to 3, characterized in that: The weighing range of the weighing system (3) is the total mass of all materials on the weighing platform, with a measuring range of 0-200kg and an accuracy of more than 0.001kg.

9. The particle gradation detection system with automatic weighing and particle size detection functions according to any one of claims 1 to 3, characterized in that: The transfer bridge (4) is a flexible connection structure, comprising two flexible telescopic belts, which are fixed on both sides between the rockfill particle weighing platform (2) and the rotating discharging platform (5), and the flexible telescopic belts can be extended and retracted according to the rotation of the rotating discharging platform (5).

10. The particle grading detection system with automatic weighing and particle size detection functions according to any one of claims 1 to 3, characterized in that: The discharging platform (5) can rotate to both sides within an angle of 40°.

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