Bucket wheel machine cantilever angle control method

Abstract

The present invention relates to the field of bucket wheel excavator material collection, and in particular to a bucket wheel excavator cantilever angle control method, comprising: step one: obtaining a three-dimensional model of a material pile, dividing the three-dimensional model of the material pile into multiple layers of waiting areas, and determining the material collection entry point of the waiting material collection layer; step two: obtaining the bucket wheel position, the cantilever pitch angle and the rotation angle according to the position data of the material collection entry point, keeping the cantilever pitch angle unchanged, rotating in a preset direction, and judging in real time whether the bucket wheel has reached the material collection boundary, if it has reached the material collection boundary, proceeding to step three, if it has not reached the material collection boundary, controlling the cantilever to continue rotating in a preset direction; step three: lowering the cantilever pitch angle to a preset pitch angle, rotating in the opposite direction of the preset direction, and carrying out material collection of the next layer. The method solves the problem that empty sweeping or incomplete material collection occurs during the existing bucket wheel excavator material collection process, and the pitch angle and rotation angle of the cantilever are manually controlled, which increases the labor intensity of the staff.

Description

Technical Field

[0001] The invention relates to the field of bucket wheel machine cantilever detection, and more specifically, to a bucket wheel machine cantilever angle control method. Background Art

[0002] The existing bucket wheel stacker and reclaimer mainly includes: a bucket wheel machine installed at the bottom, a cantilever movably connected to the bucket wheel machine, and a bucket wheel installed at the end of the cantilever. Among them, the bucket wheel machine can run along a pre-set track, thereby driving the cantilever to produce displacement; the cantilever can rotate horizontally or pitch around the pitch rotation point. When performing the material reclaiming operation, after the bucket wheel machine moves to the appropriate position, the bucket wheel is controlled to rotate. The rotation of the bucket wheel causes the material to be brought to the belt of the cantilever, and then transferred along the belt of the cantilever to the belt in the middle of the track, and then transported to other areas through the belt in the middle of the track.

[0003] At present, bucket wheel stackers are mostly used for loading and unloading bulk materials in steel raw material yards, power plant coal yards, and port bulk cargo yards. With the improvement of automation level and the application of information and digital technology, the yard is committed to unmanned control of stackers. The three-dimensional model of the stockpile in the stockpile is the prerequisite for unmanned control. The establishment of the three-dimensional model of the stockpile in the stockpile through laser scanning and other methods is a current research hotspot. However, in the process of retrieving materials, empty scanning or incomplete retrieving may occur. It is also necessary to manually control the pitch angle and rotation angle of the cantilever, which requires the operator to concentrate for a long time, which will increase the labor intensity of the operator. Long working hours also lead to low production efficiency and cannot meet production needs. Summary of the invention

[0004] The present invention provides a bucket wheel machine boom angle control method, which is used to solve the problem that empty sweeping or incomplete material taking occurs during the existing bucket wheel machine material taking process, and artificially controlling the boom pitch angle and rotation angle increases the labor intensity of the staff, and the long working time also leads to low production efficiency. The method comprises:

[0005] Step 1: Obtain a three-dimensional model of the stockpile, divide the three-dimensional model of the stockpile into multiple layers of waiting areas, and determine a material entry point for the waiting material layer, wherein the material entry point is the closest point to the initial position of the bucket wheel excavator in the waiting material area;

[0006] Step 2: According to the position data of the material entry point, the bucket wheel machine position, the pitch angle and the rotation angle of the boom are obtained, the bucket wheel is moved to the material entry point, the pitch angle of the boom is kept unchanged, and it is rotated in the preset direction. It is judged in real time whether the bucket wheel has reached the material reclaiming boundary. If it has reached the material reclaiming boundary, step 3 is performed. If it has not reached the material reclaiming boundary, the bucket wheel machine is advanced to the material pile direction by a preset distance, and the boom is controlled to continue to rotate in the preset direction until the bucket wheel reaches the material reclaiming boundary.

[0007] Step 3: Lower the pitch angle of the cantilever to the preset pitch angle, rotate in the opposite direction of the preset direction, and proceed to the next layer of material collection according to step 2 until the material collection of the bottom layer is completed.

[0008] In the embodiment of the present application, in step 2, the position of the bucket wheel machine, the pitch angle and the rotation angle of the boom are obtained according to the position data of the material entry point, specifically:

[0009] The position data of the material entry point is obtained to obtain the horizontal two-dimensional coordinates, which are recorded as point A (x, y), where the origin in the horizontal two-dimensional coordinate system is the initial position of the bucket wheel machine, the direction of the bucket wheel machine's running track is the X-axis, and the direction perpendicular to the X-axis is the Y-axis;

[0010] The pitch angle of the cantilever is calculated according to the following formula, and the pitch angle of the cantilever is α:

[0011]

[0012] Among them, H A is the distance from the material entry point A to the ground, H is the distance from the cantilever's pitch center to the ground, and L is the length from the cantilever's pitch center to the bucket wheel;

[0013] The rotation angle of the cantilever is calculated according to the following formula, and the rotation angle of the cantilever is θ:

[0014]

[0015] The position D of the bucket wheel machine is calculated according to the following formula:

[0016] D=x+L·cosα·cosθ

[0017] In the embodiment of the present application, in step 2, the pitch angle of the cantilever remains unchanged, and it rotates in a preset direction to determine in real time whether the bucket wheel reaches the material taking boundary, specifically:

[0018] Determine the position data information of the material taking boundary according to the three-dimensional model of the coal pile in step 1, the material taking boundary is composed of a plurality of points, obtain the horizontal two-dimensional coordinates of the plurality of points in the material taking boundary, calculate the distance between any two points in the material taking boundary, and calculate the average value thereof as Z, and set the average value error interval (Z1, Z2) according to the average value Z;

[0019] The bucket wheel intersects with the material-taking layer at point P1. The horizontal two-dimensional coordinates of point P1 are obtained, and the distance s1 between point P1 and any point within the material-taking boundary is calculated. If s1 is within the mean value error interval, it is determined that the bucket wheel has reached the material-taking boundary. If s1 is not within the mean value error interval, it is determined that the bucket wheel has not reached the material-taking boundary.

[0020] In an embodiment of the present application, the method further includes checking the pitch angle of the cantilever, specifically:

[0021] Two different pitch positioning devices are installed on the cantilever. The two pitch positioning devices can detect the pitch angle of the cantilever in real time. The angles collected by the two pitch positioning devices are subtracted to obtain the difference Q1, and (a1, b1) is set as the first difference interval, (c1, d1) is set as the second difference interval, and (e1, f1) is set as the third difference interval, where b1≤c1, d1≤e1,

[0022] If the difference Q1 is in the first difference interval (a1, b1), the angle difference collected by the two sets of pitch positioning devices is within the normal difference range, and the boom operates normally;

[0023] If the difference Q1 is in the second difference interval (c1, d1), the angle difference collected by the two sets of pitch positioning devices is at the boundary of the normal difference range, and the boom operates at a reduced speed;

[0024] If the difference Q1 is in the third difference interval (e1, f1), the angle difference collected by the two pitch positioning devices is outside the normal difference range, and the boom is suspended;

[0025] If the two sets of pitch positioning devices detect that the pitch angle of the boom reaches a pitch angle threshold, the boom will suspend operation. The pitch angle threshold is the maximum pitch angle when the bucket wheel excavator is retrieving materials.

[0026] In an embodiment of the present application, the method further includes checking the rotation angle of the cantilever, specifically:

[0027] Two different sets of rotary positioning devices are installed on the cantilever. The two sets of rotary positioning devices can detect the rotary angle of the cantilever in real time. The angles collected by the two sets of rotary positioning devices are subtracted to obtain the difference Q2, and (a2, b2) is set as the fourth difference interval, (c2, d2) is set as the fifth difference interval, and (e2, f2) is set as the sixth difference interval, where b2≤c2, d2≤e2,

[0028] If the difference Q2 is in the fourth difference interval (a2, b2), the angle difference collected by the two sets of rotary positioning devices is within the normal difference range, and the cantilever operates normally;

[0029] If the difference Q2 is in the fifth difference interval (c2, d2), the angle difference collected by the two sets of rotary positioning devices is at the boundary of the normal difference range, and the cantilever reduces the speed of operation;

[0030] If the difference Q2 is in the sixth difference interval (e2, f2), the angle difference collected by the two sets of rotary positioning devices is outside the normal difference range, and the cantilever is suspended;

[0031] If the two sets of rotary positioning devices detect that the swing angle of the boom reaches a swing angle threshold, the boom will suspend operation. The swing angle threshold is the maximum swing angle when the bucket wheel excavator is retrieving materials.

[0032] In an embodiment of the present application, before the cantilever rotates in the opposite direction of the preset direction in step three, the cantilever is rotated by a preset angle, specifically:

[0033] The preset rotation angle is determined according to the pitch angle of the cantilever, and the pitch angles of the cantilever are set as follows: α1 is the first pitch angle, α2 is the second pitch angle, and α3 is the third pitch angle, wherein α1>α2>α3, and the preset rotation angle β1 is set as the first preset angle, β2 is the second preset angle, and β3 is the third preset angle, wherein β1>β2>β3;

[0034] When the pitch angle of the cantilever is the first pitch angle α1, the preset rotation angle is set to the third preset angle β3;

[0035] When the pitch angle of the cantilever is the second pitch angle α2, the preset rotation angle is set to the second preset angle β2;

[0036] When the pitch angle of the cantilever is the third pitch angle α3, the preset rotation angle is set to the first preset angle β1.

[0037] In an embodiment of the present application, the method further includes adjusting the rotation speed according to the rotation angle of the cantilever when the cantilever rotates in a preset direction, specifically:

[0038] Set the rotation speed V1 as the first rotation speed, V2 as the second rotation speed, and V3 as the third rotation speed, wherein V1>V2>V3, set the rotation angle θ1 as the first rotation angle, θ2 as the second rotation angle, and θ3 as the third rotation angle, wherein θ1<θ2<θ3;

[0039] When the rotation angle obtained in real time is the first rotation angle θ1, the selected rotation speed is the third rotation speed V3;

[0040] When the rotation angle obtained in real time is the second rotation angle θ2, the rotation speed is selected as the second rotation speed V2;

[0041] When the rotation angle acquired in real time is the third rotation angle θ3, the rotation speed is selected as the first rotation speed V1.

[0042] In an embodiment of the present application, before step 3, the method further includes:

[0043] Collect the pile shape data of the area to be taken in real time, and adjust the preset pitch angle of the cantilever according to the real-time shape of the pile.

[0044] In an embodiment of the present application, the method further includes detecting the distance between the cantilever and the bucket wheel machine's walking track and obstacles, and sending a warning signal if the obstacle distance exceeds the safe distance, specifically:

[0045] The obstacle distance is preset to d, and the safety distance is measured in real time according to the position of the cantilever and the bucket wheel machine, and D1 is set as the first safety distance, D2 is set as the second safety distance, and D3 is set as the third safety distance, and D1>D2>D3;

[0046] When d>D1, the obstacle distance is greater than the first safety distance, and no warning signal is sent;

[0047] When D2<d<D1, the obstacle distance is between the first safety distance and the second safety distance, and a general warning signal is sent;

[0048] When D3<d<D2, the obstacle distance is between the second safety distance and the third safety distance, an important warning signal is sent;

[0049] When d<D3, the obstacle distance is less than the third safety distance, and an emergency warning signal is sent.

[0050] In an embodiment of the present application, a bucket wheel machine boom angle control system is also included, which is characterized by comprising:

[0051] A laser scanning device is arranged on one side of the cantilever to obtain a three-dimensional model of the stockpile to determine the position data of the material entry point and the material boundary;

[0052] A stockpile database is used to store the three-dimensional coordinates of key points on the stockpile, including material entry points and material boundary points. The three-dimensional coordinates change in real time according to the shape of the stockpile;

[0053] A verification module, used to obtain the cantilever rotation angle and pitch angle in real time by using different positioning devices, and to verify the cantilever rotation angle and pitch angle obtained by different positioning devices, wherein the positioning devices include an absolute value encoding positioning device, a non-contact pitch positioning device, and a non-contact rotation positioning device;

[0054] The control module is used to connect the stockpile database and the verification module, detect the cantilever angle in real time and send a control signal.

[0055] Compared with the prior art, the embodiments of this application bring the following beneficial effects:

[0056] The present invention provides a method for controlling the cantilever angle of a bucket wheel machine, comprising: step one: obtaining a three-dimensional model of a material pile, dividing the three-dimensional model of the material pile into multiple layers of waiting areas, and determining a material entry point of the waiting material layer, wherein the material entry point is the closest point to the initial position of the bucket wheel machine in the waiting material area; step two: obtaining the bucket wheel machine position, the cantilever pitch angle and the rotation angle according to the position data of the material entry point, moving the bucket wheel to the material entry point, keeping the cantilever pitch angle unchanged, rotating in a preset direction, and judging in real time whether the bucket wheel has reached the material taking boundary, if it has reached the material taking boundary, proceeding to step three, if it has not reached the material taking boundary, making the bucket wheel machine advance a preset distance in the direction of the material pile, and controlling the cantilever to continue to rotate in a preset direction until the bucket wheel reaches the material taking boundary; step three: lowering the cantilever pitch angle to a preset pitch angle, rotating in the opposite direction of the preset direction, and proceeding to take the material of the next layer according to step two, until the material taking of the bottommost material taking layer is completed. The method determines the position data of the material picking entry point through the three-dimensional model of the material pile, collects the pile shape data of the area to be picked in real time during the material picking process, and automatically adjusts the pitch angle and rotation angle of the cantilever to ensure that the bucket wheel reaches the material picking boundary to ensure complete material picking, thereby solving the problem of empty sweeping or incomplete material picking during the existing bucket wheel machine retrieving process, and the artificial control of the cantilever pitch angle and rotation angle increases the labor intensity of the staff, and the long working hours also lead to low production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0058] Figure 1 1 is a schematic flow chart of a bucket wheel machine boom angle control method according to an embodiment of the present invention;

[0059] Figure 2 is a schematic diagram of a bucket wheel machine boom angle control system in an embodiment of the present application;

[0060] Figure 3 It is a schematic diagram of a process for determining whether the bucket wheel has reached the material taking boundary in an embodiment of the present application;

[0061] Figure 4 is a schematic diagram of the process of pitch angle calibration in an embodiment of the present application;

[0062] Figure 5 It is a schematic diagram of the process of rotation angle verification in the embodiment of the present application. DETAILED DESCRIPTION

[0063] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0064] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0065] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0066] like Figure 1 As shown, a bucket wheel machine boom angle control method according to an embodiment of the present invention comprises:

[0067] Step 1: Obtain a three-dimensional model of the stockpile, divide the three-dimensional model of the stockpile into multiple layers of waiting areas, and determine a material entry point for the waiting material layer, wherein the material entry point is the closest point to the initial position of the bucket wheel excavator in the waiting material area;

[0068] Step 2: According to the position data of the material entry point, the bucket wheel machine position, the pitch angle and the rotation angle of the boom are obtained, the bucket wheel is moved to the material entry point, the pitch angle of the boom is kept unchanged, and it is rotated in the preset direction. It is judged in real time whether the bucket wheel has reached the material reclaiming boundary. If it has reached the material reclaiming boundary, step 3 is performed. If it has not reached the material reclaiming boundary, the bucket wheel machine is advanced to the material pile direction by a preset distance, and the boom is controlled to continue to rotate in the preset direction until the bucket wheel reaches the material reclaiming boundary.

[0069] Step 3: Lower the pitch angle of the cantilever to the preset pitch angle, rotate in the opposite direction of the preset direction, and proceed to the next layer of material collection according to step 2 until the material collection of the bottom layer is completed.

[0070] In the embodiment of the present application, in step 2, the position of the bucket wheel machine, the pitch angle and the rotation angle of the boom are obtained according to the position data of the material entry point, specifically:

[0071] The position data of the material entry point is obtained to obtain the horizontal two-dimensional coordinates, which are recorded as point A (x, y), where the origin in the horizontal two-dimensional coordinate system is the initial position of the bucket wheel machine, the direction of the bucket wheel machine's running track is the X-axis, and the direction perpendicular to the X-axis is the Y-axis;

[0072] The pitch angle of the cantilever is calculated according to the following formula, and the pitch angle of the cantilever is α:

[0073]

[0074] Among them, H A is the distance from the material entry point A to the ground, H is the distance from the cantilever's pitch center to the ground, and L is the length from the cantilever's pitch center to the bucket wheel;

[0075] The rotation angle of the cantilever is calculated according to the following formula, and the rotation angle of the cantilever is θ:

[0076]

[0077] The position D of the bucket wheel machine is calculated according to the following formula:

[0078] D=x+L·cosα·cosθ

[0079] In this embodiment, x is the length of the material picking entry point A on the X-axis, and y is the length of the material picking entry point on the Y-axis. The material picking entry points of multiple layers of the waiting area can be determined and calculated according to the above formula. During the material picking process, the material pile information of the waiting area is collected in real time, and the material picking entry point is adjusted to adjust the pitch angle and rotation angle of the cantilever.

[0080] like Figure 3 As shown, in the embodiment of the present application, in step 2, the pitch angle of the cantilever remains unchanged, and rotates in a preset direction to determine in real time whether the bucket wheel reaches the material taking boundary, specifically:

[0081] Determine the position data information of the material taking boundary according to the three-dimensional model of the coal pile in step 1, the material taking boundary is composed of a plurality of points, obtain the horizontal two-dimensional coordinates of the plurality of points in the material taking boundary, calculate the distance between any two points in the material taking boundary, and calculate the average value thereof as Z, and set the average value error interval (Z1, Z2) according to the average value Z;

[0082] The bucket wheel intersects with the material-taking layer at point P1. The horizontal two-dimensional coordinates of point P1 are obtained, and the distance s1 between point P1 and any point within the material-taking boundary is calculated. If s1 is within the mean value error interval, it is determined that the bucket wheel has reached the material-taking boundary. If s1 is not within the mean value error interval, it is determined that the bucket wheel has not reached the material-taking boundary.

[0083] In this embodiment, the rotation angle of the cantilever is set to θ', the bucket wheel intersects with the material layer to be taken at point P1, and the two-dimensional coordinates of point P1 in the horizontal plane are obtained as P1 (x1, y1). The distance s1 between point P1 and any point within the material taking boundary is calculated, and the average value error interval (Z1, Z2) is set according to the average value Z. If s1 is within (Z1, Z2), it is judged that the bucket wheel has reached the material taking boundary. If s1 is not within (Z1, Z2), it is judged that the bucket wheel has not reached the material taking boundary.

[0084] like Figure 4 As shown, in an embodiment of the present application, the method further includes checking the pitch angle of the cantilever, specifically:

[0085] Two different pitch positioning devices are installed on the cantilever. The two pitch positioning devices can detect the pitch angle of the cantilever in real time. The angles collected by the two pitch positioning devices are subtracted to obtain the difference Q1, and (a1, b1) is set as the first difference interval, (c1, d1) is set as the second difference interval, and (e1, f1) is set as the third difference interval, where b1≤c1, d1≤e1,

[0086] If the difference Q1 is in the first difference interval (a1, b1), the angle difference collected by the two sets of pitch positioning devices is within the normal difference range, and the boom operates normally;

[0087] If the difference Q1 is in the second difference interval (c1, d1), the angle difference collected by the two sets of pitch positioning devices is at the boundary of the normal difference range, and the boom operates at a reduced speed;

[0088] If the difference Q1 is in the third difference interval (e1, f1), the angle difference collected by the two pitch positioning devices is outside the normal difference range, and the boom is suspended;

[0089] If the two sets of pitch positioning devices detect that the pitch angle of the boom reaches a pitch angle threshold, the boom will suspend operation. The pitch angle threshold is the maximum pitch angle when the bucket wheel excavator is retrieving materials.

[0090] In this embodiment, two different pitch positioning devices are respectively an absolute value encoding positioning device and a non-contact pitch positioning device. The angles collected by the two pitch positioning devices are converted into the same unit and then subtracted. A pitch angle threshold is set on both pitch positioning devices, and the pitch angle of the cantilever should be less than the pitch angle threshold. As long as one of the pitch positioning devices detects that the pitch angle of the cantilever reaches the pitch angle threshold, the cantilever will suspend operation.

[0091] like Figure 5 As shown, in an embodiment of the present application, the method further includes checking the rotation angle of the cantilever, specifically:

[0092] Two different sets of rotary positioning devices are installed on the cantilever. The two sets of rotary positioning devices can detect the rotary angle of the cantilever in real time. The angles collected by the two sets of rotary positioning devices are subtracted to obtain the difference Q2, and (a2, b2) is set as the fourth difference interval, (c2, d2) is set as the fifth difference interval, and (e2, f2) is set as the sixth difference interval, where b2≤c2, d2≤e2,

[0093] If the difference Q2 is in the fourth difference interval (a2, b2), the angle difference collected by the two sets of rotary positioning devices is within the normal difference range, and the cantilever operates normally;

[0094] If the difference Q2 is in the fifth difference interval (c2, d2), the angle difference collected by the two sets of rotary positioning devices is at the boundary of the normal difference range, and the cantilever reduces the speed of operation;

[0095] If the difference Q2 is in the sixth difference interval (e2, f2), the angle difference collected by the two sets of rotary positioning devices is outside the normal difference range, and the cantilever is suspended;

[0096] If the two sets of rotary positioning devices detect that the swing angle of the cantilever reaches a swing angle threshold, the cantilever will suspend operation. The swing angle threshold is the maximum swing angle when the bucket wheel excavator is retrieving materials.

[0097] In this embodiment, the two different sets of rotary positioning devices are respectively an absolute value encoding positioning device and a non-contact rotary positioning device. The angles collected by the two sets of rotary positioning devices are converted into the same unit and then subtracted. A rotation angle threshold is set on the two sets of rotary positioning devices. The rotation angle of the cantilever should be less than the rotation angle threshold. As long as one of the rotary positioning devices detects that the rotation angle of the cantilever reaches the rotation angle threshold, the cantilever will suspend operation.

[0098] In an embodiment of the present application, before the cantilever rotates in the opposite direction of the preset direction in step three, the method further includes rotating the cantilever by a preset angle, specifically:

[0099] The preset rotation angle is determined according to the pitch angle of the cantilever, and the pitch angles of the cantilever are set as follows: α1 is the first pitch angle, α2 is the second pitch angle, and α3 is the third pitch angle, wherein α1>α2>α3, and the preset rotation angle β1 is set as the first preset angle, β2 is the second preset angle, and β3 is the third preset angle, wherein β1>β2>β3;

[0100] When the pitch angle of the cantilever is the first pitch angle α1, the preset rotation angle is set to the third preset angle β3;

[0101] When the pitch angle of the cantilever is the second pitch angle α2, the preset rotation angle is set to the second preset angle β2;

[0102] When the pitch angle of the cantilever is the third pitch angle α3, the preset rotation angle is set to the first preset angle β1.

[0103] In this embodiment, in order to ensure that the material of this layer is completely taken, the cantilever is rotated to a preset angle. The preset rotation angle is an additional rotation angle. The larger the pitch angle, the smaller the angle required for additional rotation will be. This is because the width of the material pile to the bottom layer will become larger and larger, and the larger the horizontal width of the remaining part of the material pile will be, the larger the angle required for delayed rotation will be.

[0104] In an embodiment of the present application, the method further includes adjusting the rotation speed according to the rotation angle of the cantilever when the cantilever rotates in a preset direction, specifically:

[0105] Set the rotation speed V1 as the first rotation speed, V2 as the second rotation speed, and V3 as the third rotation speed, wherein V1>V2>V3, set the rotation angle θ1 as the first rotation angle, θ2 as the second rotation angle, and θ3 as the third rotation angle, wherein θ1<θ2<θ3;

[0106] When the rotation angle obtained in real time is the first rotation angle θ1, the selected rotation speed is the third rotation speed V3;

[0107] When the rotation angle obtained in real time is the second rotation angle θ2, the rotation speed is selected as the second rotation speed V2;

[0108] When the rotation angle acquired in real time is the third rotation angle θ3, the rotation speed is selected as the first rotation speed V1.

[0109] In this embodiment, the rotation speed will increase when the rotation angle is larger, so when the rotation angle is different, the rotation speed of the cantilever should be adjusted. Different rotation angles correspond to different rotation speeds, which can improve the bucket wheel excavator's material collection capacity per unit time.

[0110] In an embodiment of the present application, before step 3, the method further includes:

[0111] Collect the pile shape data of the area to be taken in real time, and adjust the preset pitch angle of the cantilever according to the real-time shape of the pile.

[0112] In this embodiment, the preset pitch angle is determined according to the material entry point of the multi-layer material collection area. The laser scanning device installed on one side of the cantilever collects the shape of the material pile in real time. In order to adapt to the real-time collected shape of the material pile, the preset pitch angle of the cantilever is automatically adjusted.

[0113] In an embodiment of the present application, the method further includes detecting the distance between the cantilever and the bucket wheel machine's walking track and obstacles, and sending a warning signal if the obstacle distance exceeds the safe distance, specifically:

[0114] The obstacle distance is preset to d, and the safety distance is measured in real time according to the position of the cantilever and the bucket wheel machine, and D1 is set as the first safety distance, D2 is set as the second safety distance, and D3 is set as the third safety distance, and D1>D2>D3;

[0115] When d>D1, the obstacle distance is greater than the first safety distance, and no warning signal is sent;

[0116] When D2<d<D1, the obstacle distance is between the first safety distance and the second safety distance, and a general warning signal is sent;

[0117] When D3<d<D2, the obstacle distance is between the second safety distance and the third safety distance, an important warning signal is sent;

[0118] When d<D3, the obstacle distance is less than the third safety distance, and an emergency warning signal is sent.

[0119] like Figure 2 As shown, in an embodiment of the present application, a bucket wheel machine boom angle control system is also included, which is characterized by comprising:

[0120] A laser scanning device is arranged on one side of the cantilever to obtain a three-dimensional model of the stockpile to determine the position data of the material entry point and the material boundary;

[0121] A stockpile database is used to store the three-dimensional coordinates of key points on the stockpile, including material entry points and material boundary points. The three-dimensional coordinates change in real time according to the shape of the stockpile;

[0122] A verification module, used to obtain the cantilever rotation angle and pitch angle in real time by using different positioning devices, and to verify the cantilever rotation angle and pitch angle obtained by different positioning devices, wherein the positioning devices include an absolute value encoding positioning device, a non-contact pitch positioning device, and a non-contact rotation positioning device;

[0123] The control module is used to connect the stockpile database and the verification module, detect the cantilever angle in real time and send a control signal.

[0124] Those skilled in the art will appreciate that the modules in the system in the implementation scenario can be distributed in the system of the implementation scenario according to the implementation scenario description, or can be changed accordingly and located in one or more systems different from the implementation scenario. The modules in the above implementation scenario can be combined into one module, or can be further split into multiple sub-modules.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A bucket wheel machine boom angle control method, characterized in that: include: Step 1: Obtain a three-dimensional model of the stockpile, divide the three-dimensional model of the stockpile into multiple layers of waiting areas, and determine a material entry point for the waiting material layer, wherein the material entry point is the closest point to the initial position of the bucket wheel excavator in the waiting material area; Step 2: According to the position data of the material entry point, the bucket wheel machine position, the pitch angle and the rotation angle of the boom are obtained, the bucket wheel is moved to the material entry point, the pitch angle of the boom is kept unchanged, and it is rotated in the preset direction. It is judged in real time whether the bucket wheel has reached the material reclaiming boundary. If it has reached the material reclaiming boundary, step 3 is performed. If it has not reached the material reclaiming boundary, the bucket wheel machine is advanced to the material pile direction by a preset distance, and the boom is controlled to continue to rotate in the preset direction until the bucket wheel reaches the material reclaiming boundary. Step 3: lower the pitch angle of the cantilever to the preset pitch angle, rotate in the opposite direction of the preset direction, and proceed to the next layer of material collection according to step 2 until the material collection of the bottom layer is completed; In step 2, the position of the bucket wheel machine, the pitch angle and the rotation angle of the boom are obtained according to the position data of the material entry point, specifically: The position data of the material entry point is obtained to obtain the horizontal two-dimensional coordinates, which are recorded as point A (x, y), where the origin in the horizontal two-dimensional coordinate system is the initial position of the bucket wheel machine, the direction of the bucket wheel machine's running track is the X-axis, and the direction perpendicular to the X-axis is the Y-axis; The pitch angle of the cantilever is calculated according to the following formula, and the pitch angle of the cantilever is α: ； Among them, H A is the distance from the material entry point A to the ground, H is the distance from the cantilever's pitch center to the ground, and L is the length from the cantilever's pitch center to the bucket wheel; The rotation angle of the cantilever is calculated according to the following formula, and the rotation angle of the cantilever is θ: ； The position D of the bucket wheel machine is calculated according to the following formula: D = x + L·cosα·cosθ; In step 2, the pitch angle of the cantilever remains unchanged and rotates in the preset direction to determine in real time whether the bucket wheel has reached the material-reclaiming boundary. Specifically: Determine the position data information of the material taking boundary according to the three-dimensional model of the coal pile in step 1, the material taking boundary is composed of a plurality of points, obtain the horizontal two-dimensional coordinates of the plurality of points in the material taking boundary, calculate the distance between any two points in the material taking boundary, and calculate the average value thereof as Z, and set the average value error interval (Z1, Z2) according to the average value Z; The bucket wheel intersects with the material-taking layer at point P1, obtains the horizontal two-dimensional coordinate of point P1, and calculates the distance s1 between point P1 and any point within the material-taking boundary. If s1 is within the mean value error interval, it is determined that the bucket wheel has reached the material-taking boundary. If s1 is not within the mean value error interval, it is determined that the bucket wheel has not reached the material-taking boundary. The method further includes checking the pitch angle of the cantilever, specifically: Two different pitch positioning devices are installed on the cantilever. The two pitch positioning devices can detect the pitch angle of the cantilever in real time. The angles collected by the two pitch positioning devices are subtracted to obtain the difference Q1, and (a1, b1) is set as the first difference interval, (c1, d1) is set as the second difference interval, and (e1, f1) is set as the third difference interval, where b1≤c1, d1≤e1, If the difference Q1 is in the first difference interval (a1, b1), the angle difference collected by the two sets of pitch positioning devices is within the normal difference range, and the boom operates normally; If the difference Q1 is in the second difference interval (c1, d1), the angle difference collected by the two sets of pitch positioning devices is at the boundary of the normal difference range, and the boom operates at a reduced speed; If the difference Q1 is in the third difference interval (e1, f1), the angle difference collected by the two pitch positioning devices is outside the normal difference range, and the boom is suspended; If the two sets of pitch positioning devices detect that the pitch angle of the boom reaches a pitch angle threshold, the boom will suspend operation. The pitch angle threshold is the maximum pitch angle when the bucket wheel excavator is retrieving materials.

2. The bucket wheel machine boom angle control method according to claim 1, characterized in that: The method further includes checking the rotation angle of the cantilever, specifically: Two different sets of rotary positioning devices are installed on the cantilever. The two sets of rotary positioning devices can detect the rotary angle of the cantilever in real time. The angles collected by the two sets of rotary positioning devices are subtracted to obtain the difference Q2, and (a2, b2) is set as the fourth difference interval, (c2, d2) is set as the fifth difference interval, and (e2, f2) is set as the sixth difference interval, where b2≤c2, d2≤e2, If the difference Q2 is in the fourth difference interval (a2, b2), the angle difference collected by the two sets of rotary positioning devices is within the normal difference range, and the cantilever operates normally; If the difference Q2 is in the fifth difference interval (c2, d2), the angle difference collected by the two sets of rotary positioning devices is at the boundary of the normal difference range, and the cantilever operates at a reduced speed; If the difference Q2 is in the sixth difference interval (e2, f2), the angle difference collected by the two sets of rotary positioning devices is outside the normal difference range, and the cantilever is suspended; If the two sets of rotary positioning devices detect that the swing angle of the cantilever reaches the swing angle threshold, the cantilever will suspend operation. The swing angle threshold is the maximum swing angle when the bucket wheel excavator is retrieving materials.

3. The bucket wheel machine boom angle control method according to claim 1, characterized in that: The method in step 3 further includes rotating the cantilever by a preset angle before the cantilever rotates in the opposite direction of the preset direction, specifically: The preset rotation angle is determined according to the pitch angle of the cantilever, and the pitch angles of the cantilever are set as follows: α1 is the first pitch angle, α2 is the second pitch angle, and α3 is the third pitch angle, wherein α1>α2>α3, and the preset rotation angle β1 is set as the first preset angle, β2 is the second preset angle, and β3 is the third preset angle, wherein β1>β2>β3; When the pitch angle of the cantilever is the first pitch angle α1, the preset rotation angle is set to the third preset angle β3; When the pitch angle of the cantilever is the second pitch angle α2, the preset rotation angle is set to the second preset angle β2; When the pitch angle of the cantilever is the third pitch angle α3, the preset rotation angle is set to the first preset angle β1.

4. The bucket wheel machine boom angle control method according to claim 1, characterized in that: The method further includes adjusting the rotation speed according to the rotation angle of the cantilever when the cantilever rotates in a preset direction, specifically: Set the rotation speed V1 as the first rotation speed, V2 as the second rotation speed, and V3 as the third rotation speed, wherein V1>V2>V3, set the rotation angle θ1 as the first rotation angle, θ2 as the second rotation angle, and θ3 as the third rotation angle, wherein θ1<θ2<θ3; When the rotation angle obtained in real time is the first rotation angle θ1, the selected rotation speed is the third rotation speed V3; When the rotation angle obtained in real time is the second rotation angle θ2, the rotation speed is selected as the second rotation speed V2; When the rotation angle acquired in real time is the third rotation angle θ3, the rotation speed is selected as the first rotation speed V1.

5. The bucket wheel machine boom angle control method according to claim 1, characterized in that: Before step 3, the method further includes: Collect the pile shape data of the area to be taken in real time, and adjust the preset pitch angle of the cantilever according to the real-time shape of the pile.

6. The bucket wheel machine boom angle control method according to claim 1, characterized in that: The method further includes detecting the distance between the cantilever and the bucket wheel machine's travel track and obstacles, and sending a warning signal if the obstacle distance exceeds the safe distance, specifically: The obstacle distance is preset to d, and the safety distance is measured in real time according to the position of the cantilever and the bucket wheel machine, and D1 is set as the first safety distance, D2 is set as the second safety distance, and D3 is set as the third safety distance, and D1>D2>D3; When d>D1, the obstacle distance is greater than the first safety distance, and no warning signal is sent; When D2<d<D1, the obstacle distance is between the first safety distance and the second safety distance, and a general warning signal is sent; When D3<d<D2, the obstacle distance is between the second safety distance and the third safety distance, an important warning signal is sent; When d<D3, the obstacle distance is less than the third safety distance, and an emergency warning signal is sent.

7. The bucket wheel machine boom angle control method according to any one of claims 1 to 6, further comprising a bucket wheel machine boom angle control system, characterized in that: include: A laser scanning device is arranged on one side of the cantilever to obtain a three-dimensional model of the stockpile to determine the position data of the material entry point and the material boundary; A stockpile database is used to store the three-dimensional coordinates of key points on the stockpile, including material entry points and material boundary points. The three-dimensional coordinates change in real time according to the shape of the stockpile; A verification module, used to obtain the cantilever rotation angle and pitch angle in real time by using different positioning devices, and to verify the cantilever rotation angle and pitch angle obtained by different positioning devices, wherein the positioning devices include an absolute value encoding positioning device, a non-contact pitch positioning device, and a non-contact rotation positioning device; The control module is used to connect the stockpile database and the verification module, detect the cantilever angle in real time and send a control signal.

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