Lifting device

Abstract

To derive a coordinate system in which an influence of swinging of a floating object due to tide and movement of the floating object due to waves is reduced.SOLUTION: An unloading device 100 includes a position attitude deriving part 156 for deriving position attitude information that is information on a position or an attitude of a floating object coordinate system based on a predetermined position of the floating object with respect to a ground coordinate system based on a predetermined position of the ground, in which the position attitude information is information processed by a low-pass filter. Thereby, a coordinate system in which swinging of a floating object due to tide and an influence of movement of the floating object due to waves are reduced is derived.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a lifting apparatus. [Background technology]

[0002] A lifting device removes cargo loaded inside a floating body from the floating body. An unloader device is an example of a lifting device. Another example of a floating body is a ship. An unloader device derives a route for unloading cargo loaded on the ship based on a coordinate system based on a predetermined position of the ship (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-131393 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in the above Patent Document 1, when a ship is rocked by waves, the coordinate system itself moves in accordance with the rocking of the ship. However, since the moving speed of the scraping unit that unloads the cargo is slow, there is a risk that the movement of the coordinate system will cause the ship to deviate from its course.

[0005] On the other hand, if the scraping unit is moved based on a coordinate system based on a predetermined position on the ground, it is not possible to take into account the movement of the ship due to tides, and there is a risk of collision between the ship and the scraping unit.

[0006] Therefore, there is a need to propose a coordinate system that can accommodate both the rocking of a ship due to waves and the movement of the ship due to tides.

[0007] In view of these problems, the present disclosure aims to provide a floating object monitoring device capable of deriving a coordinate system that reduces the effects of the swaying of floating objects due to tides and the movement of floating objects due to waves. [Means for solving the problem]

[0008] In order to solve the above problem, a lifting device according to one aspect of the present disclosure includes a vertical transport mechanism that lifts cargo from a ship's hold, a distance measurement sensor provided on the vertical transport mechanism that periodically measures a distance to an object on the ship, a position and attitude derivation unit that derives position and attitude information, which is information regarding a position or attitude of a floating object coordinate system based on a predetermined position on the ship, relative to a ground coordinate system based on a predetermined position on the ground, from measurement data from the distance measurement sensor, and a low-pass filter unit that applies a low-pass filter to the position and attitude information. The low-pass filter unit applies a low-pass filter to the position and attitude information at a cutoff frequency between a frequency at which the ship is swayed by waves and a frequency at which the ship moves due to tides. .

[0011] load The lifting device may be equipped with a path generating unit that generates a path for lifting the cargo along the position of the side wall of the hold based on the position and attitude information that has been subjected to a low-pass filter, and the vertical transport mechanism may lift the cargo along the path derived by the path generating unit. Effect of the Invention

[0012] The lifting device makes it possible to derive a coordinate system that reduces the effects of the swaying of floating objects due to tides and the movement of floating objects due to waves. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a diagram illustrating an outline of an unloader device. [Diagram 2] FIG. 2 is a diagram illustrating a configuration of an unloader device. [Diagram 3] FIG. 2 is a diagram illustrating a measurement range of a distance measuring sensor. [Figure 4] FIG. 2 is a diagram illustrating a measurement range of a distance measuring sensor. [Diagram 5] FIG. 2 is a diagram illustrating a measurement range of a distance measuring sensor. [Figure 6] FIG. 2 is a diagram illustrating a measurement range of a distance measuring sensor. [Figure 7] FIG. 2 is a diagram illustrating the electrical configuration of the unloader device. [Figure 8] 13 is a flowchart showing a process for creating a hold model and determining whether or not an approach has occurred. [Figure 9] FIG. 4 is a diagram illustrating a coordinate system of the unloader device. [Figure 10] FIG. 4 is a diagram illustrating a coordinate system of the unloader device. [Figure 11] FIG. 2 is a diagram illustrating measurement points of a distance measuring sensor. [Figure 12] FIG. 13 is a diagram showing how edge points are detected. [Figure 13] FIG. 2 is a diagram illustrating a cutoff frequency of a low-pass filter. [Figure 14] FIG. 13 is a diagram illustrating an automatic route. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values ​​shown in the embodiment are merely examples for ease of understanding, and do not limit the present disclosure unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present disclosure are not illustrated.

[0015] Fig. 1 is a diagram for explaining an overview of an unloader device 100. As shown in Fig. 1, the unloader device 100, which is an example of a lifting device, is capable of traveling on a pair of rails 3 laid along a quay 2 in the extension direction of the rails 3. The unloader device 100 unloads to the outside a cargo 6 loaded in a hold 5 of a ship 4 anchored at the quay 2. The cargo 6 is assumed to be bulk cargo, and one example is coal.

[0016] Fig. 2 is a diagram illustrating the configuration of the unloader apparatus 100. Note that Fig. 2 shows a cross section of the quay 2 and the ship 4. As shown in Fig. 2, the unloader apparatus 100 includes a traveling body 102, a rotating body 104, a boom 106, a top frame 108, an elevator 110, a scraping unit 112, and a boom conveyor 114. Note that the top frame 108, the elevator 110, and the scraping unit 112 function as a vertical transport mechanism that carries out the cargo 6 from the hold 5.

[0017] The running body 102 is driven by an actuator (not shown) to run on the rails 3. A position sensor 116 is provided on the running body 102. The position sensor 116 is, for example, a rotary encoder. The position sensor 116 measures the position of the running body 102 on a horizontal plane relative to a predetermined origin position based on the number of rotations of the wheels of the running body 102.

[0018] The rotating body 104 is provided on the upper part of the running body 102 so as to be rotatable about a vertical axis. The rotating body 104 can rotate with respect to the running body 102 by being driven by an actuator (not shown).

[0019] The boom 106 is provided on the upper part of the revolving body 104 so that its inclination angle can be changed. The boom 106 is driven by an actuator (not shown) so that its inclination angle with respect to the revolving body 104 can be changed.

[0020] The rotating body 104 is provided with a rotation angle sensor 118 and a tilt angle sensor 120. The rotation angle sensor 118 and the tilt angle sensor 120 are, for example, rotary encoders. The rotation angle sensor 118 measures the rotation angle of the rotating body 104 with respect to the traveling body 102. The tilt angle sensor 120 measures the tilt angle of the boom 106 with respect to the rotating body 104.

[0021] The top frame 108 is provided at the tip of the boom 106. The top frame 108 is provided with an actuator that rotates the elevator 110.

[0022] The elevator 110 is formed in a substantially cylindrical shape. The elevator 110 is supported by the top frame 108 so as to be rotatable about a central axis. A rotation angle sensor 122 is provided on the top frame 108. The rotation angle sensor 122 is, for example, a rotary encoder. The rotation angle sensor 122 measures the rotation angle of the elevator 110 with respect to the top frame 108.

[0023] The scraping unit 112 is provided at the lower end of the elevator 110. The scraping unit 112 rotates integrally with the elevator 110 as the elevator 110 rotates.

[0024] The scraping unit 112 is provided with a plurality of buckets 112a and a chain 112b. The plurality of buckets 112a are continuously arranged on the chain 112b. The chain 112b is stretched over the inside of the scraping unit 112 and the elevator 110.

[0025] The scraping unit 112 is provided with a link mechanism (not shown). The link mechanism is movable to vary the length of the bottom of the scraping unit 112. This allows the scraping unit 112 to vary the number of buckets 112a that come into contact with the cargo 6 in the hold 5. The scraping unit 112 rotates the chain 112b, causing the buckets 112a at the bottom to scrape off the cargo 6 in the hold 5. Then, the buckets 112a that have scraped off the cargo 6 move to the top of the elevator 110 as the chain 112b rotates.

[0026] The boom conveyor 114 is provided below the boom 106. The boom conveyor 114 transports the load 6 that has been moved to the upper part of the elevator 110 by the bucket 112a to the outside.

[0027] The unloader apparatus 100 thus configured moves in the extending direction of the rail 3 by the traveling body 102, and adjusts the relative positional relationship with the ship 4 in the longitudinal direction. In addition, the unloader apparatus 100 rotates the boom 106, the top frame 108, the elevator 110, and the scraping unit 112 by the rotating body 104, and adjusts the relative positional relationship with the ship 4 in the transverse direction. In addition, the unloader apparatus 100 moves the top frame 108, the elevator 110, and the scraping unit 112 in the vertical direction by the boom 106, and adjusts the relative positional relationship with the ship 4 in the vertical direction. In addition, the unloader apparatus 100 rotates the elevator 110 and the scraping unit 112 by the top frame 108. In this way, the unloader apparatus 100 can move the scraping unit 112 to any position and angle.

[0028] Here, the ship 4 is provided with a number of holds 5. A hatch coaming 7 is provided at the top of each hold 5. The hatch coaming 7 has a wall surface of a given height in the vertical direction. The hatch coaming 7 has a smaller opening area than the horizontal cross section near the center of the hold 5. In other words, the hold 5 has a shape in which the opening is narrowed by the hatch coaming 7. A hatch cover 8 for opening and closing the hatch coaming 7 is provided above the hatch coaming 7.

[0029] The unloader device 100 is provided with distance measuring sensors 130-136 as measuring instruments. The distance measuring sensors 130-136 are, for example, laser sensors capable of measuring distances, and VLP-16 and VLP-32 manufactured by Velodyne, M8 manufactured by Quanergy, etc. are applied. The distance measuring sensors 130-136 are provided with 16 laser irradiation units spaced apart along the axial direction on the side of a cylindrical main body, for example. The laser irradiation units are provided on the main body so as to be rotatable 360 ​​degrees. The laser irradiation units are respectively arranged so that the difference in the axial laser emission angle between the laser irradiation units arranged adjacent to each other is 1 to 2.5 degrees apart. In other words, the distance measuring sensors 130-136 can irradiate a laser in a range of 360 degrees in the circumferential direction of the main body. The distance measuring sensors 130-136 can also emit a laser in a range of ±15 degrees based on a plane perpendicular to the axial direction of the main body. Further, the distance measuring sensors 130 to 136 each have a receiving section for receiving a laser provided in the main body.

[0030] Distance measuring sensors 130-136 rotate a laser emitting unit and irradiate a laser at every predetermined angle. Distance measuring sensors 130-136 receive lasers irradiated (projected) from the multiple laser emitting units and reflected by an object (measurement point) at a receiving unit. Distance measuring sensors 130-136 then derive the distance to the object based on the time from when the laser is irradiated to when it is received. That is, distance measuring sensors 130-136 measure the distance to multiple measurement points on one measurement line using one laser emitting unit. Distance measuring sensors 130-136 also measure the distance to multiple measurement points on multiple measurement lines using multiple laser emitting units.

[0031] Figures 3 and 4 are diagrams illustrating the measurement ranges of distance measuring sensors 130-132. Figure 3 is a diagram illustrating the measurement ranges of distance measuring sensors 130-132 when unloader apparatus 100 is viewed from above. Figure 4 is a diagram illustrating the measurement ranges of distance measuring sensors 130-132 when unloader apparatus 100 is viewed from the side. In Figures 3 and 4, the measurement ranges of distance measuring sensors 130-132 are indicated by dashed lines.

[0032] The distance measuring sensors 130-132 are mainly used when detecting the hatch coaming 7. The distance measuring sensors 130-132 are attached to the side of the top frame 108 as shown in Figs. 3 and 4. Specifically, the distance measuring sensors 130-132 are arranged 120 degrees apart from each other in the circumferential direction with the central axis of the elevator 110 as a reference. The distance measuring sensors 130-132 are also arranged so that the central axis of the main body is aligned in the radial direction of the elevator 110. The upper half of the distance measuring sensors 130-132 in the vertical direction is covered by a cover (not shown).

[0033] Therefore, as shown in Figures 3 and 4, the distance measuring sensors 130-132 can measure the distance to an object that is located below the horizontal plane and within a range of ±15 degrees from the tangent line that touches the side of the top frame 108.

[0034] 5 and 6 are diagrams for explaining the measurement ranges of the distance measuring sensors 133-136. FIG. 5 is a diagram for explaining the measurement ranges of the distance measuring sensors 133-136 when the scraping unit 112 is viewed from above. In FIG. 5, only the scraping unit 112 of the unloader device 100 is illustrated. In addition, FIG. 5 shows a horizontal cross section of the ship 4 at the same position in the vertical direction as the scraping unit 112. FIG. 6 is a diagram for explaining the measurement ranges of the distance measuring sensors 133-136 when the unloader device 100 is viewed from the side. In FIG. 5 and FIG. 6, the measurement ranges of the distance measuring sensors 133 and 134 are indicated by dashed lines. In addition, in FIG. 5 and FIG. 6, the measurement ranges of the distance measuring sensors 135 and 136 are indicated by dashed lines.

[0035] Distance measuring sensors 133-136 are mainly used to detect cargo 6 in hold 5 and the wall surfaces (side walls and bottom surface) of hold 5. Distance measuring sensor 133 is attached to side surface 112c of scraping unit 112 as shown in Figs. 5 and 6. Distance measuring sensor 133 is disposed so that the central axis of the main body is perpendicular to side surface 112c of scraping unit 112. Distance measuring sensor 134 is attached to side surface 112d of scraping unit 112. Distance measuring sensor 134 is disposed so that the central axis of the main body is perpendicular to side surface 112d of scraping unit 112. Distance measuring sensors 133 and 134 are partially covered in the vertical direction by a cover (not shown).

[0036] Therefore, distance measuring sensors 133 and 134 can measure the distance to an object that exists in a range of ±15 degrees from a position parallel to side surfaces 112c and 112d of scraping unit 112, which is a part of the upper side and a part of the lower side of side surfaces 112c and 112d of scraping unit 112 as a measurement direction. Note that distance measuring sensors 133 and 134 of this embodiment are arranged on a plane on which the bottom of scraping unit 112 is located so as to be able to measure a range at least equal to or greater than the maximum length of the bottom of scraping unit 112.

[0037] Distance measurement sensor 135 is attached to side surface 112c of scraping unit 112. Distance measurement sensor 135 is disposed so that the central axis of the main body is perpendicular to the bottom surface of scraping unit 112. Distance measurement sensor 136 is attached to side surface 112d of scraping unit 112. Distance measurement sensor 136 is disposed so that the central axis of the main body is perpendicular to the bottom surface of scraping unit 112.

[0038] Therefore, the distance measuring sensors 135 and 136 can measure the distance to an object that is outside the scraping portion 112 and within a predetermined angle range based on a horizontal plane perpendicular to the sides 112c and 112d of the scraping portion 112 (or a plane perpendicular to the central axis of the main body).

[0039] When the distance measuring sensors 130 to 136 measure the distance to the object, they transmit measurement data indicating the distance to the object to the unloader control unit 140 (see FIG. 7).

[0040] Fig. 7 is a diagram for explaining the electrical configuration of the unloader device 100. As shown in Fig. 7, the unloader device 100 is provided with an unloader control unit 140, a storage unit 142, and a display unit 144.

[0041] The unloader control unit 140 is connected to the position sensor 116, the turning angle sensor 118, the tilt angle sensor 120, the turning angle sensor 122, the distance measuring sensors 130-136, the memory unit 142, and the display unit 144. The unloader control unit 140 is composed of a semiconductor integrated circuit including a CPU (Central Processing Unit). The unloader control unit 140 reads out programs and parameters for operating the CPU itself from the ROM. The unloader control unit 140 then manages and controls the entire unloader device 100 in cooperation with a RAM as a work area and other electronic circuits.

[0042] Furthermore, the unloader control unit 140 functions as a drive control unit 150, a measurement data acquisition unit 152, an edge detection unit 154, a position and orientation derivation unit 156, a low-pass filter unit 158, a path generation unit 160, and an automatic driving unit 162. The drive control unit 150 controls the drive of the unloader device 100. Other functional units of the unloader control unit 140 will be described in detail later.

[0043] The storage unit 142 is a storage medium such as a hard disk, a non-volatile memory, etc. The storage unit 142 stores a model of the hold 5, which will be described later in detail.

[0044] The display unit 144 is an LED display, an organic EL display, etc. On the display unit 144, an image in which a three-dimensional model of the unloader device 100 is arranged relative to a three-dimensional model of the hold 5 is displayed.

[0045] Fig. 8 is a flowchart showing the flow of processing performed by the unloader control unit 140. As shown in Fig. 8, when the processing starts, first, the measurement data acquisition unit 152 acquires measurement data of the measurement points measured by the distance measurement sensors 130-136 at any time (S100). Note that the measurement data acquisition unit 152 periodically acquires measurement data from each of the distance measurement sensors 130-136 at a frequency of 1 to 5 times per second from the time when the scraping unit 112 starts scraping the cargo 6 in the hold 5 until all of the cargo 6 is scraped (for example, 10 hours).

[0046] 9 and 10 are diagrams for explaining the coordinate system of the unloader apparatus 100. Fig. 9 is a diagram of the unloader apparatus 100 seen from above. Fig. 10 is a diagram of the unloader apparatus 100 seen from the side. Here, the unloader apparatus 100 has three coordinate systems, namely, a ground coordinate system 300, a scraping section coordinate system 310, and a hatch combing coordinate system 320.

[0047] 9 and 10, the ground coordinate system 300 has its origin at a predetermined position previously set on the quay 2 (ground), for example, the initial position of the unloader device 100. In the ground coordinate system 300, the Xa-axis direction is a direction perpendicular to the extension direction of the rail 3 and the vertical direction. In the ground coordinate system 300, the Ya-axis direction is the extension direction of the rail 3. In the ground coordinate system 300, the Za-axis direction is the vertical direction.

[0048] The scraping unit coordinate system 310 is on the central axis of the elevator 110, and has the lower end of the top frame 108 in the vertical direction as its origin. In the scraping unit coordinate system 310, the direction from the origin toward the center of the tip portion 112e of the scraping unit 112 is the Xb axis direction. In the scraping unit coordinate system 310, the extension direction of the elevator 110 is the Zb axis direction. In the scraping unit coordinate system 310, the direction perpendicular to the Xb axis direction and the Zb axis direction is the Ya axis direction.

[0049] The hatch coaming coordinate system 320 is the center position of the stern side wall surface of the hatch coaming 7 of the ship 4, and has the upper end of the hatch coaming 7 as the origin (a specified position of the ship 4). The hatch coaming coordinate system 320 has the Xc axis direction which is the longitudinal direction of the ship 4, that is, the extension direction of the hatch coaming 7 along the ship 4. The hatch coaming coordinate system 320 has the Yc axis direction which is the short side direction (width direction) of the ship 4. The hatch coaming coordinate system 320 has the Zc axis direction which is perpendicular to the upper end surface of the hatch coaming 7.

[0050] Then, every time the measurement data acquisition unit 152 acquires measurement data from the distance measurement sensors 130 to 136, the position and orientation derivation unit 156 uses equation (1) to calculate the position and orientation of the hatch combing coordinate system 320 as viewed from the ground coordinate system 300. GR T HC is derived (S102).

number

[0051] Also, position and posture GR T BE indicates the position and orientation of the scraping unit coordinate system 310 as viewed from the ground coordinate system 300. HC T BE indicates the position and orientation of the scraping unit coordinate system 310 as viewed from the hatch combing coordinate system 320.

[0052] Here, the position and rotation of the origin of the scraping unit coordinate system 310 as viewed from the ground coordinate system 300 can be geometrically derived based on the shape of the unloader apparatus 100, the movement of the unloader apparatus 100, and the rotation of the scraping unit 112. Therefore, the position and orientation derivation unit 156 derives the position and orientation based on the shape of the unloader apparatus 100, the movement of the unloader apparatus 100, and the rotation of the scraping unit 112. GR T BE Derive.

[0053] In addition, since the distance measuring sensors 130-132 are attached to the top frame 108, their positions in the scraping unit coordinate system 310 are known in advance. Therefore, the edge detection unit 154 detects the upper edge of the hatch combing 7 based on the measurement data of the measurement points measured by the distance measuring sensors 130-132. Then, the position and orientation derivation unit 156 determines the position and orientation based on the detected upper edge of the hatch combing 7. HC T BE Derive.

[0054] Specifically, first, the edge detection unit 154 derives the three-dimensional position of the measurement point in the scraping unit coordinate system 310 based on the positions of the distance measurement sensors 130-132 and the distances and directions to the measurement points measured by the distance measurement sensors 130-132.

[0055] Fig. 11 is a diagram for explaining the measurement points of the distance measuring sensors 130-132. In Fig. 11, the measurement ranges of the distance measuring sensors 130-132 on the hatch combing 7 are indicated by thick lines. As shown in Fig. 11, the distance measuring sensors 130-132 are below the horizontal plane and measure the distance to an object existing within a range of ±a predetermined angle from the distance measuring sensors 130-132 with respect to a plane that is in contact with the top frame 108.

[0056] Therefore, the distance measuring sensors 130-132 use the vertically downward direction (the rotation center of the elevator 110) of the distance measuring sensors 130-132 as a reference point, and the measurement range is the edge of the hatch combing 7, which differs between the front side and the rear side. Note that the front side refers to the measurement range measured in the first half of one measurement, and the rear side refers to the measurement range measured in the second half of one measurement.

[0057] Therefore, the measurement points measured by the distance measuring sensors 130-132 are divided into two, a front side and a rear side, with a point vertically below the distance measuring sensors 130-132 as a reference.

[0058] Fig. 12 is a diagram showing how edge points are detected. In Fig. 12, measurement points are indicated by black circles. Fig. 12 illustrates measurement points measured by a laser irradiated by one of the laser irradiation units of distance measuring sensors 130 to 132.

[0059] The edge detection unit 154 performs the following process for each group of measurement points (for each front side and rear side) of one measurement line irradiated and measured by one laser irradiation unit. The edge detection unit 154 derives the vector (direction) of each measurement point irradiated and measured by one laser irradiation unit. Note that the vector of the measurement point is calculated by deriving the direction (vector) of the next measurement point measured relative to one measurement point among the measurement points measured consecutively as the vector of one measurement point.

[0060] Then, the edge detection unit 154 extracts the measurement point whose vector is in the vertical direction. This is because the wall surface (side surface) of the hatch combing 7 measured by the distance measurement sensors 130 to 132 extends in the approximately vertical direction, and therefore, when the measurement point is on the wall surface of the hatch combing 7, the vector of the measurement point is in the vertical direction.

[0061] Then, when there are a plurality of consecutively extracted measurement points among the extracted measurement points, the edge detection unit 154 extracts the uppermost point in the vertical direction. This is because, in order to detect the upper edge of the hatch combing 7, the uppermost point in the group of consecutively measured measurement points may be the upper edge of the hatch combing 7.

[0062] Next, the edge detection unit 154 extracts the measurement point closest to the origin in the Xb-axis direction and the Yb-axis direction in the scraping unit coordinate system 310 from among the extracted measurement points. In other words, the edge detection unit 154 extracts the measurement point closest to the central axis of the elevator 110. This is because the hatch coaming 7 is located closest to the elevator 110 among the structures of the ship 4.

[0063] Then, the edge detection unit 154 re-extracts measurement points that exist within a predetermined range (for example, a range of several tens of centimeters) in the Xb-axis direction and the Yb-axis direction in the scraping unit coordinate system 310 with respect to the extracted measurement points. Here, the measurement points on the hatch combing 7 are extracted.

[0064] Then, the edge detection unit 154 extracts the re-extracted measurement point, that is, the uppermost measurement point in the vertical direction among the measurement points on the hatch combing 7, as an edge point of the hatch combing 7.

[0065] The edge detection unit 154 extracts front and rear edge points for each group of measurement points measured by irradiating with a laser irradiation unit of one of the distance measuring sensors 130-132.

[0066] Then, when all edge points are extracted, the edge detection unit 154 detects straight lines of the edges of the hatch combing 7. Specifically, the edge detection unit 154 groups the edge points extracted on the front side of the distance measurement sensor 130 into one group. Similarly, the edge detection unit 154 groups the edge points extracted on the rear side of the distance measurement sensor 130 into one group. Furthermore, the edge detection unit 154 groups the edge points extracted on the front side and rear side of the distance measurement sensors 131 and 132 into groups.

[0067] Here, as shown in FIG. 11, when the straight lines of the upper edge of the hatch combing 7 measured on the front and rear sides of the distance measuring sensors 130 to 132 include the corners of the hatch combing 7, two straight lines are measured.

[0068] Therefore, the edge detection unit 154 derives, for each group, the line segment between the extracted edge points that has the most similar line segments as a candidate vector.The edge detection unit 154 then extracts edge points that exist within a range set in advance for the candidate vector.The edge detection unit 154 then recalculates the straight line using the extracted edge points.

[0069] Next, the edge detection unit 154 repeats the above process using the edge points that were not extracted. However, if the number of extracted edge points is less than a preset threshold, no straight line is derived. This makes it possible to derive straight lines for two edges even when the corners of the hatch combing 7 are included.

[0070] The edge detection unit 154 derives the straight lines of the edges by repeatedly performing the above process for each group. In this way, a maximum of two straight lines of the edges are detected at one location, so a maximum of 12 straight lines of the edges are detected.

[0071] Then, the edge detection unit 154 derives the angles between the detected straight lines. If the angles between the straight lines are equal to or smaller than a predetermined threshold, the edge detection unit 154 integrates the straight lines as being the same straight line. Specifically, the edge detection unit 154 re-derives straight lines by least squares approximation using edge points that form straight lines whose angles are equal to or smaller than a predetermined threshold.

[0072] Next, the edge detection unit 154 derives edge information from the detected edge straight lines, including the three-dimensional direction vector of each side, the three-dimensional barycentric coordinates of each side, the length of each side, and the coordinates of the endpoints of each side.

[0073] Next, the position and orientation derivation unit 156 calculates the position and orientation based on the three-dimensional model information of the hatch combing 7 stored in the storage unit 142 and the edge side information (detection result) expressed in the scraping unit coordinate system 310. HC T BE The three-dimensional model information of the hatch combing 7 indicates a three-dimensional model of the hatch combing 7 represented by the hatch combing coordinate system 320.

[0074] The position and orientation derivation unit 156 performs rough correction by rotating the orientation of the detected straight line of the edge of the hatch combing 7 by the rotation angle of the boom 106. In addition, the position and orientation derivation unit 156 associates the straight line of the detected edge of the hatch combing 7 with the upper end side of the hatch combing 7 in the 3D model information by straight lines having the closest edge orientation.

[0075] Then, the position and orientation derivation unit 156 determines the position and orientation that minimizes an evaluation function, for example, the sum of squares of the difference in distance between edge points constituting the straight line of the edge and the upper edge of the hatch combing 7 based on the 3D model information. HC T BE is calculated by, for example, the LM method. Specifically, the position and orientation are determined so that the total distance between the edge points constituting the straight line of the edge and the upper side of the hatch combing 7 based on the 3D model information, or the area of ​​the curved surface formed by the straight line of the edge and the upper side of the hatch combing 7 based on the 3D model information, is minimized.HC T BE In addition, the position and orientation are calculated as follows. HC T BE The method for obtaining is not limited to the LM method, but may be other methods such as the steepest descent method or Newton's method.

[0076] Then, the position and orientation derivation unit 156 calculates the derived position and orientation. GR T BE and position HC T BE Based on this, the position and orientation are calculated using equation (1). GR T HC The position and orientation are derived. GR T HC is derived each time measurement data is acquired by the distance measuring sensors 130-132.

[0077] The low-pass filter unit 158 ​​calculates the position and orientation by the position and orientation derivation unit 156. GR T HC Once is derived, the position and orientation GR T HC is subjected to a low-pass filter (S104).

[0078] A low-pass filter is a first-order lag filter with a predetermined cutoff frequency. However, the low-pass filter is not limited to a first-order lag filter, and may be, for example, a second-order lag filter. Any filter may be used as the low-pass filter as long as it can cut (attenuate) frequency components equal to or lower than the cutoff frequency.

[0079] Fig. 13 is a diagram for explaining the cutoff frequency of a low-pass filter. As shown in Fig. 13, the measurement data from the distance measuring sensors 130-132 includes measurement noise with a time constant of, for example, 0.5 seconds. The rocking of the ship 4 caused by the influence of waves has a time constant of, for example, 5 seconds. The movement of the ship 4 caused by the tides has a time constant of, for example, several hours to half a day.

[0080] The cutoff frequency of the low-pass filter is set to a value that attenuates the effects of the rocking of the ship 4 caused by waves and the effects of measurement noise, while the cutoff frequency of the low-pass filter is set to a value that does not attenuate the effects of the movement of the ship 4 caused by the tides.

[0081] That is, the time constant of the low-pass filter is set between the time constant of the rocking of the ship 4 due to waves and the time constant of the movement of the ship 4 due to tides. For example, the time constant of the low-pass filter is set between 10 seconds and 1 minute. In other words, the cutoff frequency of the low-pass filter is set between the frequency at which the ship 4 rocks due to waves and the frequency at which the ship 4 moves due to tides.

[0082] The low-pass filter unit 158 ​​calculates the position and orientation by the position and orientation derivation unit 156. GR T HC Once the frequency is derived, a low-pass filter that attenuates frequencies above the cutoff frequency is applied to the position and orientation. GR T HC In other words, the low-pass filtered position and orientation LPF( GR T HC ) is the position and orientation GR T HC This is information that has been processed by a low-pass filter.

[0083] This allows the position and orientation LPF ( GR T HC ) cuts (attenuates) the frequency components of the ship 4 rocking due to waves and the frequency components of measurement noise. GR T HC ) the frequency components caused by the movement of the ship 4 due to the tides remain uncut.

[0084] Next, the processing of the route generating unit 160 and the automatic driving unit 162 of the unloader device 100 will be described.

[0085] Fig. 14 is a diagram explaining the automatic path. Here, when the unloader device 100 scrapes off the cargo 6, there are roughly three steps. If the cargo 6 in the hold 5 has never been scraped off, the cargo 6 is piled up in the hold 5 in a mountain shape. Therefore, the first step is to flatten the cargo 6 in the hold 5. The first step is performed by an operator manually operating the unloader device 100.

[0086] Thereafter, when the surface of the cargo 6 loaded in the hold 5 becomes almost flat, in the second step, the scraping unit 112 is moved around the wall surface of the hold 5 several times, and then moved once around the center, as shown in Fig. 14. This second step can be automated because the path along which the scraping unit 112 moves is simple and the amount of cargo 6 scraped is stable.

[0087] Thereafter, when the cargo 6 in the hold 5 becomes small, the remaining cargo 6 is scraped off by the scraping unit 112 in the third step. In this third step, it is necessary to move the scraping unit 112 to the position of the cargo 6 remaining in the hold 5. Also, in the third step, it is necessary to move the scraping unit 112 near the bottom surface of the hold 5. Therefore, the third step is performed by an operator manually operating the unloader device 100.

[0088] In this way, of the three steps involved in scraping off the cargo 6 by the unloader device 100, the second step can be automated by the unloader device 100.

[0089] The path generating unit 160 reads out the three-dimensional model of the hold 5 stored in the memory unit 142. The three-dimensional model of the hold 5 is represented by a hatch coaming coordinate system 320.

[0090] Then, the path generating unit 160 converts the coordinate system of the 3D model of the hold 5 from the hatch coaming coordinate system 320 to the position and attitude LPF ( GR T HC ) to convert to a coordinate system using

[0091] Then, the path generating unit 160 uses the three-dimensional model of the hold 5 with the transformed coordinate system to generate an automatic path for translating the scraping unit 112 along the side wall of the hold 5, as shown in FIG. 14 (S106).

[0092] The automatic driving unit 162 moves the scraping unit 112 along the path created by the path generating unit 160 (S108). At this time, the 3D model of the hold 5 is converted into a position and orientation LPF( GR T HC ) is used to change the coordinate system. This eliminates the effect of the rocking of the ship 4 caused by waves, so that even if the moving speed of the scraping unit 112 is slow, the scraping unit 112 can move (follow) along the created route without being affected by the rocking of the ship 4 caused by waves.

[0093] Furthermore, although the frequency components that cause the ship 4 to move due to the tides are not cut off, the movement speed of the scraping unit 112 is sufficient to accommodate the movement of the ship 4 due to the tides.

[0094] Thus, the unloader device 100 uses a coordinate system that reduces the influence of the swaying of the ship 4 due to the tides and the movement of the ship 4 due to the waves as the position and attitude LPF ( GR T HC ) can be used to derive the automatic path. The unloader device 100 can move the scraping unit 112 along the created automatic path. The unloader device 100 can also reduce the influence of measurement noise.

[0095] In addition, the position and orientation LPF ( GR T HC ) represents the three axes of roll, pitch, and yaw, making it possible to easily understand the behavior of the ship 4.

[0096] Although the embodiments have been described above with reference to the accompanying drawings, it goes without saying that the present disclosure is not limited to such embodiments. It is clear that a person skilled in the art can think of various modified or altered examples within the scope of the claims, and it is understood that such examples also naturally belong to the technical scope.

[0097] For example, in the above embodiment, the floating object has been described by taking the ship 4 as an example. However, the floating object is not limited to the ship 4 as long as it floats on liquid (for example, the sea).

[0098] In addition, the position and orientation in the above embodiment GR T HC The method for deriving is just an example. GR T HC The method of deriving the position and attitude may be other methods. For example, a GPS may be attached to the ship 4, and the position and attitude may be calculated based on the information of the GPS. GR T HC may be derived.

[0099] In the above embodiment, the automatic driving unit 162 moves the scraping unit 112 along the automatic path created by the path generating unit 160. However, the automatic path created by the path generating unit 160 may be displayed on the display unit 144, and the worker may move the scraping unit 112 while checking the automatic path.

[0100] In the above embodiment, the unloader device 100 has been described as an example of the lifting device. However, the lifting device may be a continuous unloader (bucket type, belt type, vertical screw conveyor type, etc.), a pneumatic unloader, etc. [Industrial Applicability]

[0101] The present disclosure can be utilized in a lifting device. [Explanation of symbols]

[0102] 100 Unloader device (unloading device) 130 Distance sensor (measuring instrument) 131 Distance sensor (measuring instrument) 131 Distance sensor (measuring instrument) 156 Position and orientation derivation part 158 Low-pass filter section 160 Route Generation Unit

Claims

1. a vertical transport mechanism for unloading cargo from a hold of the ship; a distance sensor provided on the vertical transport mechanism for periodically measuring a distance to an object on the vessel; a position and attitude derivation unit that derives, from the measurement data from the distance measuring sensor, position and attitude information that is information regarding a position or attitude of a floating object coordinate system based on a predetermined position on the ship with respect to a ground coordinate system based on a predetermined position on the ground; a low-pass filter unit that applies a low-pass filter to the position and orientation information; Equipped with the low-pass filter unit applies the low-pass filter to the position and attitude information at a cutoff frequency between a frequency at which the ship is swayed by waves and a frequency at which the ship moves by tides; Lifting equipment.

2. The lifting device includes a path generating unit that generates a path for lifting the cargo along a position of a side wall of the hold based on the position and attitude information to which the low-pass filter has been applied, The vertical transport mechanism unloads the cargo along the route derived by the route generation unit.

2. The lifting device according to claim 1.

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