Control system, control device, and control method of crane

Abstract

To improve working efficiency.SOLUTION: A control system of a crane includes: a crane having a boom which can expand, contract, rise, and fall and a support part which is connected to the boom and may revolve; and a control device for controlling the crane. The control device performs at least one or more of expansion / contraction control and revolving control of the boom when a predetermined part of the boom is moved to a target point corresponding to a movement destination of a hanging load to move the hanging load with the hanging load hung. When it is not possible for the predetermined part to reach the target point, the control device updates a coordinate in a height direction of the target point and performs rise / fall control of the boom so that the boom reaches the target point including the updated coordinate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a crane control system, a control device, and a control method. [Background technology]

[0002] Conventionally, there have been proposed techniques for setting a transport route when transporting a suspended load using a crane. For example, there is a technique for setting a transport route so as to avoid entering a prohibited area (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-147139 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology of Patent Document 1 and the like is a technology for setting a transport route within a movable range so as to prevent the load from approaching a three-dimensional no-approach zone in which obstacles are set, but is not a technology for setting a route taking into consideration the structure of the crane. Therefore, due to the structural constraints of the crane boom, it may be difficult to move the load along the route.

[0005] One aspect of the present invention improves work efficiency by performing control taking into account the boom structure. [Means for solving the problem]

[0006] A crane control system according to one embodiment of the present invention comprises a crane having a boom that can be extended and raised, and a support part to which the boom is connected and which can be rotated, and a control device for controlling the crane, wherein the control device is configured to perform at least one of extension and extension control and rotation control of the boom when moving a specific part of the boom to a target point corresponding to the destination of the load in order to move the load while lifting the load, and if the specific part is not able to reach the target point, to update the height coordinate of the target point, and to perform raising and lowering control of the boom to reach the target point including the updated coordinate. Effect of the Invention

[0007] According to one aspect of the present invention, control is performed to reach a target point, thereby improving work efficiency. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of a crane according to a first embodiment. [Diagram 2] 1 is a diagram illustrating an example of the configuration of a crane control system according to a first embodiment. [Diagram 3] FIG. 2 is a conceptual diagram showing a travel route generated by a route generating unit according to the first embodiment. [Figure 4] 3 is a conceptual diagram illustrating a movement path generated by a path generating unit according to the first embodiment, in an XY plane. FIG. [Diagram 5] 4 is a diagram illustrating relay points set by a coordinate setting unit according to the first embodiment; FIG. [Figure 6] 4 is a diagram illustrating relay points set by a coordinate setting unit according to the first embodiment; FIG. [Figure 7] 10 is a diagram illustrating relay points after being updated by a coordinate update unit according to the first embodiment; FIG. [Figure 8] 4 is a flowchart showing a processing procedure by a calculation unit of the PLC according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The embodiment described below is an example, not a limitation of the invention, and all features and combinations described in the embodiment are not necessarily essential to the invention. In addition, the same or corresponding components in each drawing are denoted by the same or corresponding reference numerals, and the description may be omitted.

[0010] In the following, in the embodiment of the present invention, an example will be described in which a crane is used as an example of a work machine that moves a suspended load while hoisting the load. In the present embodiment, an example will be described in which a jib crane is used as an example of a crane, but the crane is not limited thereto, and may be, for example, a tower crane or a rotary crane.

[0011] (First embodiment) An overview of a crane included in a crane control system according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a side view of a crane according to this embodiment.

[0012] 1, the crane 100 includes a post 1, a boom 2, a hoisting rope 31, a hoisting rope 32, a winch 4, and a hook 5. A PLC (Programmable Logic Controller) 200 is connected to the crane 100. The PLC 200 is provided to control the crane 100.

[0013] The winch 4 includes a first winch 41 and a second winch 42 .

[0014] The first winch 41 supports the boom 2 via the hoisting rope 31. The first winch 41 changes the hoisting state (hoisting angle) of the boom 2 by winding up or winding down the hoisting rope 31.

[0015] The second winch 42 supports the hook 5 via a suspending rope 32 hung on a sheave 24 (not shown) at the tip of the boom 2. The suspending rope 32 extends downward from the tip Pc of the boom 2, and has a hook 5 provided at its lower end. A load 6, for example, may be suspended from the hook 5.

[0016] The second winch 42 raises and lowers the hook 5 by winding up or down the suspending rope 32. In other words, the second winch 42 can move the suspended load 6 in the height direction (Z-axis direction).

[0017] The post 1 is an example of a support member fixed to the ground (an example of a horizontal surface) S, and is connected to the boom 2 so that it can rotate up and down. The post 1 is composed of an upper main body portion 11 and a lower main body portion 12. The upper main body portion 11 and the lower main body portion 12 are connected by an actuator 13 (see FIG. 2) so that they can rotate relative to the ground S. The actuator 13 rotates the upper main body portion 11 relative to the lower main body portion 12, thereby controlling the rotation of the boom 2.

[0018] The boom 2 is composed of a first stage boom 21 and a second stage boom 22. The first stage boom 21 and the second stage boom 22 are connected by a hydraulic cylinder 23 (see FIG. 2) so as to be extendable and contractible. In this embodiment, an example in which the boom 2 is composed of two stages will be described, but the boom 2 is not limited to two stages and may be, for example, three or more stages.

[0019] The length L of the boom 2 is the length from the center of the foot pin Pf to the tip Pc of the boom 2. In this embodiment, the length L of the boom 2 can be changed by hydraulic control of the hydraulic cylinder. In this embodiment, the shortest length of the boom 2 is the minimum boom length Lmin, and the longest length of the boom 2 is the maximum boom length Lmax.

[0020] The boom 2 is also provided so as to be rotatable (raised and hoisted) in the vertical direction around the fulcrum of a foot pin Pf attached to the upper main body portion 11. The vertical rotation (hoisting operation) of the boom 2 is achieved by winding up or down the hoisting rope 31 by the first winch 41.

[0021] As described above, the crane 100 according to this embodiment is configured to be able to move three-dimensionally by rotating, raising and lowering, and extending / contracting the boom 2. Note that the crane 100 according to this embodiment is merely an example, and is not limited to the above-mentioned configuration. Any crane capable of rotating, raising and lowering, and extending / contracting the boom can be used for the control according to this embodiment.

[0022] The PLC 200 according to this embodiment controls the crane 100 based on the position of the tip Pc of the boom 2. The Cartesian coordinate system used for calculation in this embodiment is a coordinate system in a three-dimensional space based on the crane 100. The Cartesian coordinate system is, for example, an XYZ space based on an origin O, which is the center of rotation. In the XYZ space, the Z axis is the axis in the height direction, and the XY plane (an example of a two-dimensional coordinate plane including the X and Y axes) is a plane approximately parallel to the ground surface S (an example of a horizontal plane).

[0023] In this embodiment, the distance b is the distance between the fulcrum of the foot pin Pf and the origin O. In this embodiment, the distance b is a negative value.

[0024] Next, a description will be given of a control system for the crane 100 according to this embodiment. Fig. 2 is a diagram showing an example of the configuration of the control system SYS for the crane according to this embodiment.

[0025] As shown in FIG. 2, the crane control system SYS includes a crane 100, a PLC 200, and an input device 300.

[0026] The crane 100 has the external appearance shown in Figure 1, and includes as its control system a rotation angle detector S11, a boom length measuring instrument S12, a boom angle measuring instrument S13, a suspension rope length measuring instrument S14, an actuator 13, a hydraulic cylinder 23, a first winch 41, and a second winch 42.

[0027] The rotation angle detector S11 detects the rotation angle of the upper body portion 11 relative to the lower body portion 12, and transmits the detected rotation angle to the PLC200.

[0028] The boom length measuring instrument S12 calculates the length L of the boom 2 based on the operation of the hydraulic cylinder 23 and the like, and transmits the length L of the boom 2 to the PLC 200.

[0029] The boom angle measuring instrument S13 calculates the hoisting angle of the boom 2 based on the state of the first winch 41 (a value detected by an encoder or the like), and transmits the hoisting angle to the PLC 200.

[0030] The hanging rope length measuring device S14 calculates the length λ of the hanging rope 32 to the load 6 based on the state of the second winch 42 (a detection value detected by an encoder, etc.), and transmits the length λ of the hanging rope 32 to the load 6 to the PLC 200.

[0031] The input device 300 is a device for an operator to input information to the PLC 200. The input device 300 may include, for example, an operation lever for operating the crane 100. The input device 300 may also include a touch panel or the like that allows information to be input by touching a screen displayed on a display device (not shown).

[0032] For example, when the crane 100 performs autonomous control, the input device 300 receives input of coordinates indicating a target point of the tip Pc of the boom 2 or the suspended load 6, and outputs coordinate information indicating the target point to the PLC 200. The coordinate information indicating the target point may be, for example, position coordinates in a coordinate system of a three-dimensional space based on the crane 100, as described above. The coordinate information indicating the target point may be coordinates on an XY plane. Furthermore, the coordinate information indicating the target point may be input of any point on the ground surface.

[0033] As another example, the input device 300 may be provided with an operating lever that can be tilted in a direction included in a two-dimensional coordinate plane, and the crane 100 may move the tip Pc of the boom 2 in the tilt direction of the operating lever. In this case, the input device 300 may output a signal indicating the tilt direction of the operating lever (a direction included in the two-dimensional coordinate plane) to the PLC 200.

[0034] The PLC 200 is a control device for controlling the crane 100. It includes an input interface 201, an output interface 202, and a calculation unit 203. In FIG. 2, the PLC 200 is shown as being provided outside the crane 100, but it may be provided inside the crane 100.

[0035] The PLC 200 controls the crane to move the tip Pc (an example of a predetermined part) of the boom 2 to a target point. For example, the PLC 200 performs rotation control, extension control, and hoist control of the boom 2 when moving the tip Pc (an example of a predetermined part) of the boom 2 to a target point. In this embodiment, an example of performing rotation control, extension control, and hoist control of the boom 2 will be described. Note that this embodiment is not limited to a method of performing all of the rotation control, extension control, and hoist control simultaneously, but rather, it is sufficient if hoist control can be performed as necessary at least while the rotation control or extension control of the boom 2 is being performed.

[0036] The PLC 200 has a program for controlling the crane 100 loaded in the storage unit, and the calculation unit 203 reads the program to realize an acquisition unit 211, a path generation unit 212, a coordinate setting unit 213, a coordinate system calculation unit 214, and an output control unit 215. This enables the calculation unit 203 to perform the rotation control, extension control, and elevation control of the boom 2.

[0037] The acquisition unit 211 acquires various pieces of information based on signals received from various detectors, measuring instruments, and the like provided on the crane 100 via the input interface 201.

[0038] For example, the acquisition unit 211 may acquire the current position of the tip Pc of the boom 2 based on the rotation angle received from the rotation angle detector S11, the length L of the boom 2 received from the boom length measuring instrument S12, and the hoisting angle of the boom 2 received from the boom angle measuring instrument S13.

[0039] The acquisition unit 211 may also acquire the current position of the suspended load 6 based on the length λ of the suspending rope 32 and the current position of the tip Pc of the boom 2, both of which are received from the suspending rope length measuring instrument S14.

[0040] For example, the acquisition unit 211 acquires coordinate information indicating a target point of the tip Pc of the boom 2 based on coordinate information input as a target position (of the tip Pc of the boom 2 or the load 6) from the input device 300 or a device capable of communicating with the PLC 200. As another example, when a signal indicating the tilt direction of the above-mentioned operating lever is input from the input device 300, the acquisition unit 211 acquires, as the target point, a point moved a predetermined distance from the current value of the tip Pc of the boom 2 in the input direction.

[0041] The path generating unit 212 generates a movement path from a current position (an example of a starting position) of the tip portion (an example of a predetermined portion) Pc of the boom 2 to a target point. The movement path generated by the path generating unit 212 may have any shape, and may be, for example, a path that connects the current position to the target point with a straight line. Note that, in this embodiment, an example of generating a movement path of the tip portion Pc of the boom 2 will be described, but the target for which the movement path is generated may be any predetermined portion of the boom 2 and is not limited to the tip portion Pc.

[0042] Fig. 3 is a conceptual diagram showing a movement path generated by the path generating unit 212 according to this embodiment. The example shown in Fig. 3 shows a schematic diagram of the movement of the boom 2 in a three-dimensional space based on the origin O.

[0043] Specifically, the boom 2A at the current position before starting to move and the boom 2B after moving to the target position are shown.

[0044] The current position of the tip Pc of the boom 2A at the current point is indicated as the initial coordinates Ps (Xs, Ys, Zs). The boom 2A is at a hoisting angle γs.

[0045] The target point of the tip Pc of the boom 2B at the target point is indicated by the coordinates Pe (Xe, Ye, Ze). The boom 2B is at a hoisting angle γe.

[0046] 3, the path generating unit 212 generates a movement path 1310 that shows a straight line from the initial coordinates Ps (Xs, Ys, Zs) of the current point to the coordinates Pe (Xe, Ye, Ze) of the target point. Note that the hoisting angle γs and the hoisting angle γe of the boom 2A may be the same or different.

[0047] Fig. 4 is a conceptual diagram showing a movement path generated by the path generating unit 212 according to this embodiment on an XY plane. In the example shown in Fig. 4, the movement of the boom 2 is shown generally on the XY plane based on the origin O.

[0048] The current position of the tip Pc of the boom 2A at the current point is indicated as the initial coordinates Ps (Xs, Ys, Zs). The rotation angle of the boom 2A based on the Y axis is θs.

[0049] The target point of the tip Pc of the boom 2B at the target point is indicated by coordinates Pe (Xe, Ye, Ze). The swing angle of the boom 2A with respect to the Y axis is θe.

[0050] The coordinate setting unit 213 sets a plurality of relay points along the movement path 1310 through which the tip portion Pc moves.

[0051] FIG. 5 is a diagram illustrating relay points set by the coordinate setting unit 213 according to this embodiment. In the example shown in FIG. 5, relay points P1 to P15 set by the coordinate setting unit 213 are shown between the initial coordinate Ps (Xs, Ys, Zs) and the coordinate Pe (Xe, Ye, Ze) of the target point on a moving path 1310 projected onto an XY plane based on the origin O. As shown in FIG. 5, the relay points P1 to P15 are set at equal intervals on the moving path 1310. Note that, in this embodiment, an example in which the relay points P1 to P15 are set at equal intervals will be described, but the present invention is not limited to a method of setting the relay points at equal intervals. For example, the intervals between the relay points may be set in consideration of the speed of the tip Pc.

[0052] The relay points P1 to P15 are used as the destination of the tip part Pc. For example, when the tip part Pc is at the initial coordinates Ps (Xs, Ys, Zs), the relay point P1 is used as the destination. Then, when the tip part Pc has moved to the relay point P1, the relay point P2 is used as the destination. The calculation unit 203 according to this embodiment repeats this control. Finally, when the tip part Pc has moved to the relay point P15, the coordinates Pe (Xe, Ye, Ze) of the target point are used as the destination.

[0053] In the example shown in Fig. 5, the number of relay points is 15, but the number of relay points is not limited to 15. The number of relay points may be determined according to, for example, the length of the travel route or a user setting. Next, the control for moving to the destination will be described.

[0054] The coordinate system calculation unit 214 includes a determination unit 221 and a coordinate update unit 222, and performs processing for converting the next movement destination of the tip Pc from the Cartesian coordinate system to a polar coordinate system in which the origin O is indicated on the axis about which the crane 100 rotates. This processing is performed for the purpose of performing extension / retraction control, elevation control, and rotation control of the boom 2 based on the rotation center.

[0055] The coordinate system calculation unit 214 calculates the rotation angle θt * , boom length Lt * , undulation angle γt * The coordinates of the next destination in the Cartesian coordinate system are calculated as Pt * (Xt * ,Yt * ,Zt * ) The coordinate Pt * is the coordinate Pe of the above-mentioned relay points P1 to P15 or the target point. * (Xt * ,Yt * ,Zt * ) from the rotation angle θt * , boom length Lt * , undulation angle γt * Calculate.

[0056] As shown in FIGS. 4 and 5, in this embodiment, the rotation angle θ is based on the Y axis (in other words, offset by π / 2 when the X axis is used as the reference), but this embodiment is merely an example, and the rotation angle may also be based on the X axis.

[0057] The coordinate system calculation unit 214 according to this embodiment calculates the rotation angle θt * Calculate.

[0058]

number

[0059] The above-mentioned atan2 is a type of function used in a certain programming language, and means arctan that takes two arguments. In other words, from equation (1), the positive direction of the X axis and the * ,Yt * ) and the angle (in radians) between the line and the point is output.

[0060] The following formula (2) holds when the tip Pc is projected onto the XY plane: Note that, as described above, the distance b is a negative value.

[0061]

number

[0062] From equation (2), we can derive the following equation (3). Therefore, cosγt * can be calculated.

[0063]

number

[0064] Furthermore, sinγt * can be calculated using the following formula (4).

[0065]

number

[0066] Equation (3) and equation (4) are expressed as "cosγt *2 +sinγt *2 = 1" and transform the equation to derive equation (5).

[0067]

number

[0068] Therefore, the coordinate system calculation unit 214 uses the formula (5) to calculate the boom length Lt required for the tip Pc to reach the next destination (relay point or target point). * Calculate the calculated length Lt * Unless is not equal to or greater than the minimum boom length Lmin and equal to or less than the maximum boom length Lmax, they cannot be matched by telescopic control.

[0069] Therefore, the determination unit 221 determines the calculated length Lt * is equal to or greater than the minimum boom length Lmin and equal to or less than the maximum boom length Lmax, in other words, is within the range in which the boom 2 can be extended or retracted (can be made to coincide by extension and retraction control).

[0070] In this manner, every time the tip part Pc moves to a relay point, the determination unit 221 determines whether or not the tip part Pc can reach the next destination (relay point or target point).

[0071] The determination unit 221 determines the calculated length Lt * is in the expandable range, in other words, if it is determined that the coordinates of the tip Pc projected onto the XY plane can reach the coordinates of the relay point projected onto the XY plane, the coordinate system calculation unit 214 calculates γt * Calculate.

[0072]

number

[0073] By the way, the calculated length Lt * If the tip Pc is outside the stretchable range, the tip Pc is the next destination point (coordinate Pt * (Xt * ,Yt * ,Zt * ) of the next destination point of the tip of the boom 2 Pc. * and coordinate Yt *It is difficult to change the coordinate Zt * The change in the position of the load 6 in the height direction can be maintained by winding up or down the suspending rope 32, so that the destination of the load 6 can be maintained.

[0074] Therefore, in this embodiment, when the determination unit 221 determines that the condition is not satisfied, the coordinate update unit 222 updates the (height direction) coordinate Zt * In this embodiment, the coordinate Zt ** In this way, when the Z-axis coordinate of the next destination is updated, the calculation unit 203 calculates the updated coordinate Zt ** The boom 2 is controlled to rise and fall in order to reach the next destination, which includes the above-mentioned.

[0075] In other words, if the judgment unit 221 judges that the range is not extendable, in other words, that the coordinates of the tip Pc projected onto the XY plane cannot reach the coordinates of the relay point projected onto the XY plane, the PLC 200 performs raising and lowering control of the boom 2 to make the coordinates of the tip Pc projected onto the XY plane reach the coordinates of the relay point projected onto the XY plane.

[0076] Specifically, the formula (7) obtained by modifying the formula (5) is used. The coordinate update unit 222 calculates the length Lt * By substituting the minimum boom length Lmin or the maximum boom length Lmax into the updated coordinate Zt ** Then, the coordinate update unit 222 calculates the coordinate Pt * (Xt * ,Yt * ,Zt ** ) to update.

[0077]

number

[0078] Then, the coordinate system calculation unit 214 calculates the coordinate Zt ** The undulation angle γt when updated to * Calculate.

[0079]

number

[0080] That is, in this embodiment, the calculated length Lt * If this is not possible, set the boom 2 to the minimum boom length Lmin or the maximum boom length Lmax, and ** In other words, by performing the raising and lowering control of the boom 2, the movement control of the boom 2 can be continued.

[0081] Then, the coordinate system calculation unit 214 calculates the next rotation angle θt * , boom length Lt * , undulation angle γt * Calculate.

[0082] Furthermore, the coordinate system calculation unit 214 calculates the updated coordinate Zt ** and the coordinate Zt before the update * The difference between this and the coordinate Zt is calculated as the adjustment amount λdef of the suspending ropes 32. Then, the output control unit 215, which will be described later, generates and outputs a control signal for winding up or lowering the suspending ropes 32 by the adjustment amount λdef. In other words, the crane 100 according to this embodiment maintains the height of the suspended load 6 by winding up or lowering the suspending ropes 32 based on the updated coordinate of the destination (relay point or target point) in the height direction. Note that in this embodiment, the coordinate Zt ** An example of adjusting the height of the load 6 when the coordinate Zt ** In other words, the method is not limited to the method of adjusting the height of the load 6 when the coordinate Zt ** The height of the suspended load 6 does not need to be changed depending on the update.

[0083] After that, the output control unit 215 determines the rotation angle θt * a command signal to the actuator 13 to set the length Lt of the boom 2; *The control signal for the hydraulic cylinder 23 to set the elevation angle γt * and a control signal for the second winch 42 to wind up or wind down the suspending rope 32 corresponding to the adjustment amount λdef. Then, the output control unit 215 outputs the generated control signals to the crane 100 via the output interface 202.

[0084] In this way, the output control unit 215 in this embodiment performs one or more of the following controls: extension and retraction control of the boom 2, rotation control of the boom 2, raising and lowering control of the boom 2, and winding up or lowering control of the suspension rope 32, by outputting various control signals to the crane 100.

[0085] Next, a change in the destination of the tip Pc of the boom 2 will be described. FIG. 6 is a diagram illustrating relay points set by the coordinate setting unit 213 according to this embodiment. In FIG. 6, the tip Pc is set to an initial coordinate Ps1 and a coordinate Pe1 of a target point. Then, the coordinate setting unit 213 sets relay points P51 to P69 between the initial coordinate Ps1 and the coordinate Pe1 of the target point. FIG. 6 shows an example in which 19 relay points are set. Note that the Z-axis coordinate between the initial coordinate Ps1 and the coordinate Pe1 of the target point is set to "0". Therefore, the coordinate setting unit 213 sets the Z-axis coordinate "0" of the relay points P51 to P69.

[0086] Then, each time the tip Pc of the boom 2 moves to each of the relay points P51 to P69, the determination unit 221 determines the length Lt * It is determined whether the length Lt is equal to or greater than the minimum boom length Lmin and equal to or less than the maximum boom length Lmax. In other words, it is determined whether the next relay point P51 to P69 can be reached. * is smaller than the minimum boom length Lmin or larger than the maximum boom length Lmax, the Z-axis coordinate of the next relay point is updated. The updating method is as described above, so a description thereof will be omitted.

[0087] Fig. 7 is a diagram illustrating relay points after being updated by the coordinate update unit 222 according to this embodiment. In the example shown in Fig. 7, a movement path is generated so as to move the tip Pc from the initial coordinate Ps1 to the coordinate Pe1 of the target point.

[0088] In the example shown in FIG. 7, the tip Pc is determined by the determination unit 221 to have a length Lt * is determined to be equal to or greater than the minimum boom length Lmin and equal to or less than the maximum boom length Lmax. Therefore, the Z-axis coordinate of the relay point was not updated.

[0089] Then, the determination unit 221 determines that the relay points P61 to P69 and the coordinate Pe1 of the destination point do not satisfy the above condition. As a result, the coordinate update unit 222 updates the Z-axis coordinates of the relay points P60 to P69 and the coordinate Pe1 of the destination point. * ~P69 * and the coordinates of the target point Pe1 * will be updated.

[0090] As shown in Figure 7, the relay point P60 * ~P69 * and the coordinates of the target point Pe1 * is the coordinate of the target point Pe1 * The Z-axis coordinate is updated so that it becomes higher as the target point approaches the target point. In other words, the boom 2 cannot be shortened any further, so the target point coordinate Pe1 * As the boom 2 approaches the target point, control is performed to raise the boom 2. This control allows the coordinates of the tip Pc projected onto the XY plane to reach the coordinates of a preset target point projected onto the XY plane.

[0091] That is, the PLC 200 according to this embodiment performs control to raise the boom 2 when the tip Pc is to be further moved in the direction of the origin O (center of rotation) toward the target point when the boom 2 is at its shortest.

[0092] In the above-described control example, an example in which the boom 2 is raised has been described. However, the PLC 200 according to this embodiment is not limited to the example of raising the boom 2. For example, the PLC 200 may perform control to extend the boom 2 in order to make the tip Pc of the boom 2 reach a target point. Then, when the boom 2 reaches the maximum boom length Lmax, the PLC 200 performs control to lower the boom 2 in order to further move the tip Pc toward the target point in the opposite direction to the origin O (center of rotation).

[0093] In other words, in PLC 200, if the determination unit 221 determines that the tip Pc of the boom 2 cannot reach the target point through the extension and rotation control, the coordinate update unit 222 updates the height coordinate of the target point, and the output control unit 215 outputs a control signal to perform raising and lowering control of the boom 2 to reach the target point including the updated coordinate.

[0094] Then, the PLC 200 controls the winding up or winding down of the suspending rope 32 based on the distance that the tip portion Pc moves in the Z-axis direction (height direction) during the hoisting control of the boom 2. Specifically, the output control unit 215 outputs a control signal to the second winch 42 for controlling the winding up or winding down of the suspending rope 32.

[0095] Next, a description will be given of the processing procedure in the calculation unit 203 of the PLC 200. Fig. 8 is a flowchart showing the processing procedure in the calculation unit 203 according to this embodiment.

[0096] First, the acquisition unit 211 acquires initial coordinates (Xs, Ys, Zs) indicating the current position of the tip Pc of the boom 2 from signals from various sensors (detectors, measuring instruments) of the crane 100 (S1801).

[0097] Next, the acquisition unit 211 acquires the coordinates (Xe, Ye, Ze) of the target point of the tip portion Pc based on the information received from the input device 300 (S1802).

[0098] The route generating unit 212 generates a travel route for traveling from the initial coordinates indicating the current position to the coordinates of the destination point (S1803).

[0099] The coordinate setting unit 213 sets each point that the tip part Pc passes through when moving along the generated movement route as a relay point (S1804).

[0100] Then, the calculation unit 203 starts the movement control of the boom 2 (S1805).

[0101] The coordinate system calculation unit 214 calculates the turning angle θt of the next point based on the coordinates of the next point (relay point or target point). * is calculated (S1806).

[0102] Next, the coordinate system calculation unit 214 calculates the length Lt of the boom 2 at the next point based on the coordinates of the next point (relay point or target point). * is calculated (S1807).

[0103] The determination unit 221 determines the calculated length Lt of the boom 2. * It is determined whether or not the extension / contraction range of the boom 2 is within the extension / contraction range (S1808).

[0104] The determination unit 221 determines the calculated length Lt of the boom 2. * If it is determined that the boom 2 is in the extendable range (S1808: YES), the coordinate system calculation unit 214 calculates the coordinates of the next point (relay point or target point) and the length Lt * Based on the undulation angle γt * is calculated (S1809).

[0105] On the other hand, the determination unit 221 determines the calculated length Lt * However, when it is determined that the boom 2 is not in the extendable range (S1808: NO), the coordinate update unit 222 updates the length Lt *to the minimum boom length Lmin or the maximum boom length Lmax (S1810). For example, the length is updated to the minimum boom length Lmin or the maximum boom length Lmax, whichever is closer to the current length of the boom 2.

[0106] After that, the coordinate update unit 222 updates the length Lt * Based on (minimum boom length Lmin or maximum boom length Lmax), the Z-axis coordinate Zt of the next point ** (S1811).

[0107] Then, the coordinate system calculation unit 214 calculates the updated Z-axis coordinate Zt ** and the length of boom 2 Lt * Based on the undulation angle γt * is calculated (S1812).

[0108] Furthermore, the coordinate system calculation unit 214 calculates the updated Z-axis coordinate Zt ** and the pre-update Z-axis coordinate Zt, the adjustment amount λdef of the suspension rope 32 is calculated (S1813).

[0109] Thereafter, the output control unit 215 generates a control signal for moving to the next point and outputs it to the crane 100 (S1814). Therefore, a control signal for performing one or more of the rotation control, the extension / retraction control, and the elevation control for moving to the next point is generated and output.

[0110] Then, the calculation unit 203 judges whether or not the tip Pc of the boom 2 has reached the target point (S1815). If it is judged that the tip Pc has not reached the target point (S1815: NO), the control is performed again from 1806.

[0111] On the other hand, if the calculation unit 203 determines that the tip Pc of the boom 2 has reached the target point (S1815: YES), it ends the process.

[0112] As described above, in this embodiment, an example has been described in which the route generating unit 212 generates a travel route that connects the current point to the destination point in a straight line.

[0113] In addition, in this embodiment, since the load 6 is moved linearly, the operator can intuitively grasp the route of the load 6 to the target location at the work site or the like. Therefore, the operator can move the load 6 after recognizing objects and the like that exist on the route to the target location, thereby improving safety. Furthermore, since the rotational movement of the load 6 is suppressed, the application of centrifugal force, in other words, load to the load 6 can be suppressed.

[0114] Conventionally, in order to move the load 6 along a travel path, the operator has had to use the operating lever to perform a combination of telescopic control, swivel control, and elevation control. In contrast, in this embodiment, the load 6 can be moved linearly by performing the above-mentioned control. As a result, when the operator wants to move the load 6 linearly, this can be achieved by simple operation or by setting a target point, regardless of the restrictions imposed by the structure of the boom 2. In addition, by combining linear paths using the above-mentioned controls, it becomes easy to move the load 6 to the target point even when there are obstacles or only a limited route.

[0115] In the present embodiment, an example has been described in which the route generating unit 212 generates a linear travel route to the target point. However, the route generating unit 212 is not limited to a method of generating a linear travel route, and may generate a travel route using, for example, a combination of multiple ellipses, circles, free curves, or line segments.

[0116] Conventionally, operators have been demanding the ability to move a suspended load along an arbitrary route. However, there have been limitations to moving a suspended load along an arbitrary route due to the structure of the boom. In contrast, in this embodiment, when the tip of the boom cannot reach the target point, the above-mentioned control is performed, making it possible to make the suspended load reach the target point regardless of the limitations of the boom structure. In other words, the area in which the suspended load can be moved can be expanded. In the above-mentioned embodiment, the boom hoisting control is performed when the tip of the boom cannot reach the target point by the boom extension and contraction control. However, the above-mentioned embodiment is not limited to the case where the tip of the boom cannot reach the target point by the boom extension and contraction control. For example, when the tip of the boom cannot reach the target point due to the relationship between an obstacle and the boom structure, the height coordinate of the target point may be updated, and the boom hoisting control may be performed to reach the updated target point.

[0117] <effect> In the above-described embodiment, the target point can be reached by updating the height coordinates of points included in the movement path in consideration of the boom structure. In other words, in the above-described embodiment, it is possible to reach the target point with the lifted load, thereby improving workability.

[0118] In the above-mentioned embodiment, the PLC can generate a moving path for moving the tip of the boom to a target location by combining two or more of the swing control, the extension control, and the elevation control. Therefore, the operator does not need to perform complicated operations, and the operational burden can be reduced.

[0119] In the above-described embodiment, the calculation unit calculates the swivel angle, boom length, and boom angle for the tip to reach the next point (relay point or target point) using the calculation method using the above-described trigonometric functions. The calculation unit can make the tip reach the target point by repeating the calculation. In other words, in the above-described embodiment, the movement of the crane can be controlled using a calculation method such as trigonometric functions, which has a low calculation load and is easy to implement, using a PLC or the like. Therefore, the PLC according to the above-described embodiment can move the tip to the target point while performing calculations in real time. In other words, since there is no need to use a control device with high calculation performance, costs can be reduced.

[0120] Although the embodiments of the crane control system, control device, and control method according to the present invention have been described above, the present invention is not limited to the above-mentioned embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Naturally, these also fall within the technical scope of the present invention. [Explanation of symbols]

[0121] 100 Crane 1 Post 11 Upper body part 12 Lower body part 13 Actuator 2. Boom 21 1st boom 22 2-stage boom 23 Hydraulic cylinder 31 Descending Rope 32 Suspension rope 41 No. 1 winch 42 No. 2 winch 5. Hook Tip of the PC boom 200 PLC 211 Acquisition Department 212 Route Generation Unit 213 Coordinate setting section 214 Coordinate system calculation section 215 Output control section 221 Judgment section 222 Coordinate Update Unit 300 Input Device S11 Rotation Angle Detector S12 Boom length measuring instrument S13 Boom Angle Measuring Instrument S14 Suspension rope length measuring instrument

Claims

1. A crane having a boom that can be extended and lowered, and a support part that connects the boom and is rotatable; A control device for controlling the crane, the control device performs at least one of telescopic control and rotation control of the boom when moving a predetermined portion of the boom to a target point corresponding to a destination of the load in order to move the load while lifting the load; and when the predetermined portion is not capable of reaching the target point, updating a coordinate in a height direction of the target point, and performing a boom raising and lowering control to reach the target point including the updated coordinate. Crane control system.

2. The crane further includes a rope extending downward from the tip of the boom, The control device controls the winding up or winding down of the rope based on the updated coordinate in the height direction. The crane control system of claim 1 .

3. the control device calculates a length of the boom for causing the predetermined part to reach the target point, and determines whether the predetermined part can reach the target point depending on whether the boom can be extended or retracted to the calculated length. The crane control system of claim 1 .

4. The control device acquires the target point based on a signal from an input device capable of inputting a direction included in a two-dimensional coordinate plane, or acquires the target point based on input coordinate information. The crane control system of claim 1 .

5. A control device for controlling a crane including a boom that can be extended and lowered, and a support part to which the boom is connected and which can be rotated, an output control unit that outputs a control signal to the crane to perform at least one of telescopic control and rotation control of the boom when a predetermined portion of the boom is moved to a target point corresponding to a destination of the load in order to move the load while lifting the load; and an update unit that updates a coordinate of the target point in a height direction when the predetermined unit is not able to reach the target point, The output control unit outputs a control signal to the crane for controlling the raising and lowering of the boom in order to reach the target point including the updated coordinates. Crane control device.

6. A control method for controlling a crane including a boom that can be extended and extended and a support part that can be turned and is connected to the boom, comprising: When a predetermined portion of the boom is moved to a target point corresponding to a destination of the load in order to move the load while lifting the load, at least one of telescopic control and rotation control of the boom is performed; If the predetermined portion is not reachable to the target point, updating a height coordinate of the target point; performing boom raising and lowering control to reach the target point including the updated coordinates; How to control a crane.

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