Real-time monitoring and early warning method for stockpile in loading process based on 3d point cloud

Abstract

The present application belongs to the field of stockpile monitoring, and specifically relates to a stockpile real-time monitoring and early warning method in a loading process based on 3D point cloud, which comprises the following steps: S1: scanning a stockpile by a 3D laser scanner to obtain three-dimensional point cloud data of the stockpile; S2: calculating according to the three-dimensional point cloud data to obtain the best position for material taking and loading; S3: in the process of material taking and loading, the 3D laser scanner is used to obtain data of stockpile deformation and displacement in the process of material taking, the stockpile is monitored in real time, data of the stockpile deformation and displacement are calculated to obtain stockpile change trend data, the stockpile change trend data are analyzed, a warning is sent to a technician according to an analysis result, and a warning is given to on-site staff through a loudspeaker and an alarm lamp, so that the on-site staff can evacuate in time when the stockpile is about to slide.

Description

Technical Field

[0001] This invention relates to the field of stockpile monitoring, specifically a method for real-time monitoring and early warning of stockpiles during the loading process based on 3D point clouds. Background Technology

[0002] 3D point cloud refers to a dataset of three-dimensional coordinate points in a three-dimensional coordinate system. 3D point cloud generation refers to the process of transforming visual two-dimensional information into 3D information.

[0003] In current technology, materials are generally piled up in the factory's storage area. During factory production, workers retrieve materials using material conveying equipment, then transport them to vehicles, and finally transport them to the production workshop.

[0004] However, during the work process, as workers continuously remove material from the hopper and load it onto the truck, the material in the hopper gradually decreases, which can lead to changes in its structure and cause the material pile to suddenly slip, posing a certain danger. Therefore, this paper proposes a method for real-time monitoring and early warning of the material pile during the loading process based on 3D point cloud to address the above problem. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by this invention to solve its technical problem is: the real-time monitoring and early warning method for material piles during the loading process based on 3D point clouds, which includes the following steps:

[0007] S1: Scan the material pile using a 3D laser scanner to obtain the three-dimensional point cloud data of the material pile;

[0008] S2: Calculate the optimal location for material picking and loading based on 3D point cloud data;

[0009] S3: During the material loading and unloading process, 3D point cloud data is acquired in real time through a 3D laser scanner to obtain data on the deformation and displacement of the material pile during the material loading process, and to monitor the material pile in real time.

[0010] S4: Calculate the deformation and displacement data of the material pile to obtain the trend data of the material pile change, and analyze the trend data of the material pile change.

[0011] S5: Issue warnings to technicians based on the analysis results, and warn on-site staff via loudspeakers and alarm lights.

[0012] Preferably, in S3, before material removal, technicians determine the material pile displacement monitoring points, and then insert displacement probes into each monitoring point of the material pile through a monitoring device. The displacement sensors on the displacement probes send the coordinate information of the monitoring points in real time. The coordinate displacement information of the monitoring points is used to supplement the three-dimensional point cloud data obtained by the 3D laser scanner.

[0013] Preferably, the monitoring device includes a top frame; a pair of movable frames are fixedly connected to the bottom side of the top frame; multiple casters are fixedly connected to the bottom of the movable frames; a horizontal electric actuator is fixedly connected to the top of the top frame; a bracket is fixedly connected to the output end of the horizontal electric actuator; a lead screw is rotatably connected to the bracket; a fixed seat is connected to the lead screw via a ball screw nut pair; a first motor is fixedly connected to the side of the bracket; the output shaft of the first motor is fixedly connected to the lead screw; a vertical electric actuator is fixedly connected to the fixed seat; and an electric gripper is provided at the output end of the vertical electric actuator.

[0014] Preferably, a support base is fixedly connected to the top side of the top frame; multiple rotating shafts are rotatably connected to the top of the support base; a pull rope is fixedly connected to one end of the rotating shaft; the top end of the displacement probe is fixedly connected to the bottom end of the pull rope; a support frame is fixedly connected to the side of the top frame near the support base; an adjusting electric push rod is fixedly connected to the support frame; a drive base is fixedly connected to the output end of the adjusting electric push rod; a second motor is fixedly connected to the drive base; a drive shaft is fixedly connected to the output end of the second motor; and a transmission assembly is provided on the rotating shaft.

[0015] Preferably, the transmission assembly includes a drive gear; the drive gear is fixedly connected to a drive shaft; a cover is rotatably connected to the drive shaft; the cover is located on the side of the drive gear closer to the second motor; a spring telescopic rod is fixedly connected to the end of the rotating shaft away from the drum; a transmission gear is fixedly connected to the end of the spring telescopic rod away from the rotating shaft; and a hemispherical block is fixedly connected to the end of the transmission gear away from the spring telescopic rod.

[0016] Preferably, the top of the support base has multiple fixing grooves corresponding to the position of the rotating shaft; a fixing plate is slidably connected inside the fixing groove; a friction plate is fixedly connected to the middle of the fixing plate; the friction plate is in contact with the surface of the rotating shaft; guide rods are fixedly connected to both sides of the fixing plate; the guide rods penetrate the top wall of the support base and are slidably connected to it; a return spring is fixedly connected between the bottom side of the fixing plate and the support base; a top rod is fixedly connected to the top of the fixing plate; and a pulley is fixedly connected to the top rod at the position corresponding to the cover.

[0017] Preferably, a plurality of first slide rails are fixedly connected to the top side of the top frame; the bracket is slidably connected to the first slide rails; a second slide rail is fixedly connected to the top side of the support frame; and the drive seat is slidably connected to the second slide rail.

[0018] Preferably, a fixing frame is fixedly connected to the top frame at a position corresponding to the drum; multiple positioning sleeves are fixedly connected to the fixing frame; the pull rope passes through the positioning sleeves and is slidably connected to them.

[0019] The advantages of this invention are:

[0020] 1. This invention uses a 3D laser scanner to acquire data on the deformation and displacement of the material pile during the material removal process, monitors the material pile in real time, calculates the deformation and displacement data of the material pile to obtain the trend data of the material pile change, analyzes the trend data of the material pile change, issues early warning to technicians based on the analysis results, and warns on-site personnel through loudspeakers and alarm lights so that they can evacuate in time when the material pile is about to landslide.

[0021] 2. This invention, by setting up a horizontal electric push rod, a top frame, a movable frame, casters, a first motor, an electric gripper, a lead screw, and a vertical electric push rod, allows workers to move the top frame by pulling a traction vehicle to move it above the material pile. The casters facilitate the movement of the top frame. Then, workers control the horizontal electric push rod to push the support and electric gripper to move laterally. The first motor and lead screw control the electric gripper to move longitudinally. The vertical electric push rod controls the electric gripper to move vertically, and the electric gripper uses the electric gripper to grasp the displacement probe. The above setup delivers the displacement probe to the monitoring point, allowing it to be inserted into the material pile. This setup facilitates workers in placing displacement probes on the material pile. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a flowchart of the method of the present invention;

[0024] Figure 2 This is a schematic diagram of the top frame structure of the present invention;

[0025] Figure 3 This is a schematic diagram of the support structure of the present invention;

[0026] Figure 4 This is a schematic diagram of the support frame structure of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of the fixing plate of the present invention.

[0028] In the diagram: 11. Top frame; 12. Moving frame; 13. Caster wheel; 14. Horizontal electric actuator; 15. Bracket; 16. Lead screw; 17. First motor; 18. Fixed seat; 19. Vertical electric actuator; 191. Electric gripper; 21. Displacement probe; 22. Support seat; 23. Pull rope; 24. Drum; 241. Rotating shaft; 25. Support frame; 26. Adjusting electric actuator; 27. Drive seat; 28. Second motor; 31. Cover; 32. Drive shaft; 33. Drive gear; 34. Spring telescopic rod; 35. Transmission gear; 61. Fixed plate; 62. Guide rod; 63. Friction plate; 64. Top rod; 65. Pulley; 71. First slide rail; 72. Second slide rail; 81. Fixed frame; 82. Positioning sleeve. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Specific implementation examples are given below.

[0031] Please see Figure 1 As shown, a method for real-time monitoring and early warning of material stockpiles during the loading process based on 3D point clouds is presented. This method includes the following steps:

[0032] S1: Scan the material pile using a 3D laser scanner to obtain the three-dimensional point cloud data of the material pile;

[0033] S2: Calculate the optimal location for material picking and loading based on 3D point cloud data;

[0034] S3: During the material loading and unloading process, 3D point cloud data is acquired in real time through a 3D laser scanner to obtain data on the deformation and displacement of the material pile during the material loading process, and to monitor the material pile in real time.

[0035] S4: Calculate the deformation and displacement data of the material pile to obtain the trend data of the material pile change, and analyze the trend data of the material pile change.

[0036] S5: Issue warnings to technicians based on the analysis results, and warn on-site staff via loudspeakers and alarm lights.

[0037] Furthermore, in S3, before material removal, technicians determine the displacement monitoring points of the material pile, and then insert displacement probes 21 into each monitoring point of the material pile through the monitoring device. The displacement sensors on the displacement probes 21 send the coordinate information of the monitoring points in real time. The coordinate displacement information of the monitoring points is used to supplement the three-dimensional point cloud data obtained by the 3D laser scanner.

[0038] Furthermore, such as Figure 2 As shown, the monitoring device includes a top frame 11; a pair of movable frames 12 are fixedly connected to the bottom side of the top frame 11; multiple casters 13 are fixedly connected to the bottom of the movable frames 12; a horizontal electric actuator 14 is fixedly connected to the top of the top frame 11; a bracket 15 is fixedly connected to the output end of the horizontal electric actuator 14; a lead screw 16 is rotatably connected to the bracket 15; a fixed seat 18 is connected to the lead screw 16 via a ball screw nut pair; a first motor 17 is fixedly connected to the side of the bracket 15; the output shaft of the first motor 17 is fixedly connected to the lead screw 16; a vertical electric actuator 19 is fixedly connected to the fixed seat 18; an electric gripper 191 is provided at the output end of the vertical electric actuator 19; during use, the operator can... The traction vehicle pulls the top frame 11 to move it above the material pile. The universal casters 13 facilitate the movement of the top frame 11. Then, the operator controls the horizontal electric push rod 14 to push the bracket 15 and the electric gripper 191 to move laterally. Then, the first motor 17 and the lead screw 16 control the electric gripper 191 to move longitudinally. Then, the vertical electric push rod 19 controls the electric gripper 191 to move vertically. The electric gripper 191 is used to grasp the displacement probe 21. Then, the displacement probe 21 is sent to the monitoring point and inserted into the material pile. This setting makes it easy for the operator to place the displacement probe 21 on the material pile.

[0039] Furthermore, such as Figure 2-5As shown, a support base 22 is fixedly connected to the top side of the top frame 11; multiple rotating shafts 241 are rotatably connected to the top of the support base 22; a pull rope 23 is fixedly connected to one end of each rotating shaft 241; the top end of the displacement probe 21 is fixedly connected to the bottom end of the pull rope 23; a support frame 25 is fixedly connected to the side of the top frame 11 near the support base 22; an adjusting electric push rod 26 is fixedly connected to the support frame 25; a drive seat 27 is fixedly connected to the output end of the adjusting electric push rod 26; a second motor 28 is fixedly connected to the drive seat 27; a drive shaft 32 is fixedly connected to the output end of the second motor 28; a transmission assembly is provided on the rotating shaft 241; during use, the operator controls... Adjusting the electric actuator 26 pushes the drive seat 27 to move, thereby driving the second motor 28 to move. The drive gear 33 on the second motor 28 meshes with the transmission gear 35 connected to the rotating shaft 241, thereby driving the rotating shaft 241 to rotate and rewind the pull rope 23. The pull rope 23 is used to pull out the displacement probe 21. This setting allows the operator to easily reset the displacement probe 21. As the material pile is continuously removed, the operator needs to retract some of the displacement probes 21. This setting facilitates the operator's use. Both the first motor 17 and the second motor 28 are servo motors.

[0040] Furthermore, such as Figure 2-4 As shown, the transmission assembly includes a drive gear 33; the drive gear 33 is fixedly connected to a drive shaft 32; a cover 31 is rotatably connected to the drive shaft 32; the cover 31 is located on the side of the drive gear 33 closer to the second motor 28; a spring telescopic rod 34 is fixedly connected to the end of the rotating shaft 241 away from the drum 24; a transmission gear 35 is fixedly connected to the end of the spring telescopic rod 34 away from the rotating shaft 241; a hemispherical block is fixedly connected to the end of the transmission gear 35 away from the spring telescopic rod 34; in use, the drive gear 33 and the transmission gear 35 mesh with each other to drive the rotating shaft 241. When it is necessary to switch the drive gear... When the driving gear 33 meshes with different transmission gears 35, the teeth of the driving gear 33 and the transmission gear 35 have a certain depth. The drive seat 27 can be further pushed by the control and adjustment electric push rod 26. The driving gear 33 continues to move and insert into the teeth of the transmission gear 35. At the same time, the cover 31 will squeeze the hemispherical block, causing the hemispherical block to move towards the rotating shaft 241. Then the spring telescopic rod 34 retracts, thereby causing the transmission gear 35 to retract and separate from the driving gear 33. This allows the drive seat 27 and the driving gear 33 to continue to move, which facilitates the meshing of the driving gear 33 with different transmission gears 35.

[0041] Furthermore, such as Figure 3-5As shown, the top of the support base 22 has multiple fixing slots corresponding to the position of the rotating shaft 241; a fixing plate 61 is slidably connected inside the fixing slots; a friction plate 63 is fixedly connected to the middle of the fixing plate 61; the friction plate 63 is in contact with the surface of the rotating shaft 241; guide rods 62 are fixedly connected to both sides of the fixing plate 61; the guide rods 62 penetrate the top wall of the support base 22 and are slidably connected to it; a return spring is fixedly connected between the bottom side of the fixing plate 61 and the support base 22; a top rod 64 is fixedly connected to the top of the fixing plate 61; a pulley 65 is fixedly connected to the top rod 64 at the position corresponding to the cover 31; during the process of the drive gear 33 approaching the transmission gear 35, The cover 31 presses against the pulley 65, causing the pulley 65 to move upwards along with the push rod 64 under the arc surface of the cover 31. This, in turn, moves the fixing plate 61 upwards, causing the friction plate 63 to separate from the rotating shaft 241, thus releasing the fixation of the rotating shaft 241. When the drive gear 33 and transmission gear 35 move away from each other, the cover 31 separates from the pulley 65. Then, under the action of the return spring, the friction plate 63 will come into contact with the surface of the rotating shaft 241. Through the action of friction, the rotating shaft 241 can be fixed, thereby fixing the drum 24 and the pull rope 23, making it difficult for the rotating shaft 241 to rotate on its own.

[0042] Furthermore, such as Figure 2-3 As shown, the top side of the top frame 11 is fixedly connected to multiple first slide rails 71; the bracket 15 is slidably connected to the first slide rails 71; the top side of the support frame 25 is fixedly connected to a second slide rail 72; the drive seat 27 is slidably connected to the second slide rail 72. In use, by setting the first slide rails 71 and the second slide rails 72, the movement of the bracket 15 and the drive seat 27 can be guided respectively, thereby improving the stability of the bracket 15 and the drive seat 27. Improving the stability of the movement of the bracket 15 makes it easier for the staff to insert the displacement probe 21. The second slide rail 72 guides the drive seat 27, which facilitates the stable meshing of the drive gear 33 and the transmission gear 35.

[0043] Furthermore, such as Figure 5 As shown, a fixing frame 81 is fixedly connected to the top frame 11 at a position corresponding to the drum 24; multiple positioning sleeves 82 are fixedly connected to the fixing frame 81; the pull rope 23 passes through the positioning sleeve 82 and is slidably connected to it; in use, when the pull rope 23 is retracted to retrieve the displacement probe 21, the top end of the displacement probe 21 will insert into the interior of the positioning sleeve 82. This setting can fix and position the displacement probe 21, thereby facilitating the electric gripper 191 to grasp the displacement probe 21 and making it convenient for operators to use.

[0044] Working principle: During use, the operator can move the top frame 11 by pulling a tractor vehicle to move it above the material pile. The casters 13 facilitate the movement of the top frame 11. Then, the operator controls the horizontal electric actuator 14 to push the support 15 and the electric gripper 191 laterally. Next, the first motor 17 and the lead screw 16 control the electric gripper 191 to move longitudinally. Finally, the vertical electric actuator 19 controls the electric gripper 191 to move vertically, gripping the displacement probe 21. This setup then delivers the displacement probe 21 to the monitoring point, allowing it to insert into the material pile. This design facilitates easy placement of the probe on the material pile. The displacement probe 21 is moved by the operator through the control and adjustment electric actuator 26, which pushes the drive seat 27 to move, thereby driving the second motor 28 to move. The drive gear 33 on the second motor 28 meshes with the transmission gear 35 connected to the rotating shaft 241, thus driving the rotating shaft 241 to rotate the drum 24 and rewind the pull rope 23. The pull rope 23 is used to pull out the displacement probe 21. This setting facilitates the operator's resetting of the displacement probe 21. As material is continuously removed from the pile, the operator needs to retract some of the displacement probes 21. This setting facilitates the operator's use. Both the first motor 17 and the second motor 28 are servo motors. During use, the drive gear 33 and the transmission gear 35 mesh. The gears 35 mesh with each other to drive the shaft 241. When it is necessary to switch the drive gear 33 and different transmission gears 35, the teeth of the drive gear 33 and transmission gear 35 have a certain depth. By controlling the electric actuator 26, the drive seat 27 can be further pushed, and the drive gear 33 continues to move and insert into the teeth of the transmission gear 35. At the same time, the cover 31 will squeeze the hemispherical block, causing the hemispherical block to move closer to the shaft 241. Then, the spring telescopic rod 34 retracts, causing the transmission gear 35 to retract and separate from the drive gear 33, so that the drive seat 27 and the drive gear 33 can continue to move. This facilitates the meshing of the drive gear 33 with different transmission gears 35. 5. During the approach process, the cover 31 presses against the pulley 65, causing the pulley 65 and the push rod 64 to move upward under the arc surface of the cover 31. This, in turn, moves the fixing plate 61 upward, causing the friction plate 63 to separate from the rotating shaft 241, thus releasing the fixation of the rotating shaft 241. When the drive gear 33 and the transmission gear 35 move away, the cover 31 separates from the pulley 65. Then, under the action of the return spring, the friction plate 63 will adhere to the surface of the rotating shaft 241. Through the action of friction, the rotating shaft 241 can be fixed, thereby fixing the drum 24 and the pull rope 23, making it difficult for the rotating shaft 241 to rotate on its own. This is achieved by the provision of the first slide rail 71 and the second slide rail 72.This design guides the movement of the bracket 15 and drive seat 27, improving their stability. The improved stability of the bracket 15 facilitates the insertion and placement of the displacement probe 21. The second slide rail 72 guides the drive seat 27, ensuring stable engagement of the drive gear 33 and transmission gear 35. When the pull rope 23 retracts the displacement probe 21, its tip inserts into the positioning sleeve 82, securing and positioning it. This allows the electric gripper 191 to easily grasp the probe, simplifying its use for operators.

[0045] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A real-time monitoring device for material piles during the loading process based on 3D point clouds, characterized in that: The monitoring device includes a top frame (11); a pair of movable frames (12) are fixedly connected to the bottom side of the top frame (11); multiple casters (13) are fixedly connected to the bottom of the movable frames (12); a horizontal electric actuator (14) is fixedly connected to the top of the top frame (11); a bracket (15) is fixedly connected to the output end of the horizontal electric actuator (14); a lead screw (16) is rotatably connected to the bracket (15); a fixed seat (18) is connected to the lead screw (16) through a ball screw nut pair; a first motor (17) is fixedly connected to the side of the bracket (15); the output shaft of the first motor (17) is fixedly connected to the lead screw (16); a vertical electric actuator (19) is fixedly connected to the fixed seat (18); an electric gripper (191) is provided at the output end of the vertical electric actuator (19). A support base (22) is fixedly connected to the top side of the top frame (11); a plurality of rotating shafts (241) are rotatably connected to the top of the support base (22); a pull rope (23) is fixedly connected to one end of the rotating shaft (241); the top end of the displacement probe (21) is fixedly connected to the bottom end of the pull rope (23); a support frame (25) is fixedly connected to the side of the top frame (11) near the support base (22); an adjusting electric push rod (26) is fixedly connected to the support frame (25); a drive seat (27) is fixedly connected to the output end of the adjusting electric push rod (26); a second motor (28) is fixedly connected to the drive seat (27); a drive shaft (32) is fixedly connected to the output end of the second motor (28); a transmission assembly is provided on the rotating shaft (241); The transmission assembly includes a drive gear (33); the drive gear (33) is fixedly connected to a drive shaft (32); a cover (31) is rotatably connected to the drive shaft (32); the cover (31) is located on the side of the drive gear (33) closer to the second motor (28); a spring telescopic rod (34) is fixedly connected to one end of the rotating shaft (24) away from the drum (24); a transmission gear (35) is fixedly connected to one end of the spring telescopic rod (34) away from the rotating shaft (241); and a hemispherical block is fixedly connected to one end of the transmission gear (35) away from the spring telescopic rod (34). The top of the support base (22) is provided with multiple fixing grooves corresponding to the position of the rotating shaft (241); a fixing plate (61) is slidably connected inside the fixing groove; a friction plate (63) is fixedly connected to the middle of the fixing plate (61); the friction plate (63) is in contact with the surface of the rotating shaft (241); guide rods (62) are fixedly connected to both sides of the fixing plate (61); the guide rods (62) penetrate the top wall of the support base (22) and are slidably connected to it; a return spring is fixedly connected between the bottom side of the fixing plate (61) and the support base (22); a top rod (64) is fixedly connected to the top of the fixing plate (61); a pulley (65) is fixedly connected to the top rod (64) at the position corresponding to the cover (31).

2. The real-time monitoring device for material piles during loading based on 3D point clouds according to claim 1, characterized in that: The top side of the top frame (11) is fixedly connected to a plurality of first slide rails (71); the bracket (15) is slidably connected to the first slide rails (71); the top side of the support frame (25) is fixedly connected to a second slide rail (72); the drive seat (27) is slidably connected to the second slide rail (72).

3. The real-time monitoring device for material piles during loading based on 3D point clouds according to claim 1, characterized in that: A fixing frame (81) is fixedly connected to the top frame (11) at the position corresponding to the drum (24); a plurality of positioning sleeves (82) are fixedly connected to the fixing frame (81); the pull rope (23) passes through the positioning sleeves (82) and is slidably connected to them.

4. A method for real-time monitoring and early warning of material piles during the loading process based on 3D point clouds, characterized in that: This early warning method is applicable to the real-time monitoring device for material piles during the loading process based on 3D point clouds, as described in any one of claims 1-3; the method includes the following steps: S1: Scan the material pile using a 3D laser scanner to obtain the three-dimensional point cloud data of the material pile; S2: Calculate the optimal location for material picking and loading based on 3D point cloud data; S3: During the material loading and unloading process, 3D point cloud data is acquired in real time through a 3D laser scanner to obtain data on the deformation and displacement of the material pile during the material loading process, and to monitor the material pile in real time. S4: Calculate the deformation and displacement data of the material pile to obtain the trend data of the material pile change, and analyze the trend data of the material pile change. S5: Issue warnings to technicians based on the analysis results, and warn on-site staff via loudspeakers and alarm lights.

5. The early warning method for real-time monitoring of material piles during loading process based on 3D point clouds according to claim 4, characterized in that: Before taking out materials in S3, technicians determine the displacement monitoring points of the material pile. Then, they insert displacement probes (21) into each monitoring point of the material pile through the monitoring device. The displacement sensor on the displacement probe (21) sends the coordinate information of the monitoring point in real time. The coordinate displacement information of the monitoring point is used to supplement the three-dimensional point cloud data obtained by the 3D laser scanner.

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