crane

Abstract

To provide a crane capable of efficiently moving a suspended load to a target position while suppressing swinging of the suspended load in at least one of the target position and during the swing operation.SOLUTION: A crane is equipped with a target speed calculation unit. The target speed calculation unit determines coefficients of a plurality of monomial equations from an equation of motion of a suspended load for each of the turning and radial directions, including the length of a boom 16, the length of a main winding rope 50, and the raising and lowering angle of the boom 16 and a polynomial function for the turning angle of a swivel 12 with the elapsed time of the turning movement as a variable, consisting of a plurality of monomials each containing a different degree with respect to the elapsed time, so that the radial deflection angle and turning direction deflection angle of the suspended load at the target position are smaller than a predetermined threshold angle and the arrival time of the suspended load to the target position is minimized, and sets a target speed according to the elapsed time of the swivel 12 to the target position mentioned above.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a crane capable of moving a suspended load. [Background technology]

[0002] Conventionally, a mobile crane is known that includes a lower traveling body, an upper rotating body supported on the lower traveling body so as to be rotatable about a vertically extending central axis of rotation, and a hoisting body such as a boom or a jib. The hoisting body is attached to the front of the upper rotating body so as to be rotatable in the hoisting direction about a horizontal central axis of rotation. A hook is attached to a hoisting rope hanging from the tip of the hoisting body, and a load is connected to the hook to hoist the load. When the upper rotating body rotates with the load hoisted in this manner, the load can be moved in the hoisting direction.

[0003] Patent Document 1 discloses a method for controlling a crane that can suppress the swing of a load when the load is automatically conveyed along a preset conveying route using the crane. In this control method, the conveying route is set by point cloud data consisting of a plurality of nodes (points). Then, the control device sets a target conveying time for each section by allocating the conveying time required from the start point to the end point desired by the user to each section distance between adjacent nodes. Furthermore, the control device sets a target conveying speed for each section according to the set target conveying time. Since the target conveying speed becomes discontinuous at the boundary between sections and may cause load swing, the control device applies a target value filter to the acceleration section and deceleration section of the target conveying speed that changes in a step-like manner. The target value filter is a high-order low-pass filter based on inverse dynamics, and reduces the swing of the load by converting the target conveying speed that changes in a step-like manner as described above into a non-step target conveying speed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-158278 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the technology described in Patent Document 1, it may be difficult to suppress the swing of the suspended load at the target position depending on the work conditions. Specifically, in the above technology, the target transport time for each section is set based on the required transport time desired by the user, and the target transport speed for each section is restricted by the required transport time. For this reason, when the desired required transport time is relatively short, it is difficult to convert the stepped target transport speed into a non-stepped target transport speed that does not cause load swing by using a high-order low-pass filter based on inverse dynamics, which causes a problem that it is difficult to suppress the swing of the load at the target position.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a crane that can efficiently move a load to a target position while suppressing load swing at least either at the target position or during a rotation operation. [Means for solving the problem]

[0007] The present invention provides a crane. The crane includes a lower body, an upper body, a hoisting body, a load rope, a slewing drive unit, a hoisting body length information acquisition unit, a slewing angle detection unit, a rope length information acquisition unit, a movement information reception unit, a target speed setting unit, and a command signal generation unit. The upper body is supported by the lower body so as to be rotatable around a slewing center axis extending in the vertical direction. The hoisting body includes a hoisting body base end supported by the upper body so as to be rotatable in the hoisting direction around a horizontal rotation center axis, and a hoisting body tip end opposite to the hoisting body base end. The load rope is suspended from the hoisting body tip end and connected to a load. The slewing drive unit is capable of receiving a predetermined speed command signal and rotating the upper body around the slewing center axis at a speed corresponding to the speed command signal. The undulating body length information acquisition unit acquires undulating body length information, which is information corresponding to the length of the undulating body in the undulating body longitudinal direction, which is the direction connecting the undulating body base end and the undulating body tip end. The slewing angle detection unit detects the slewing angle of the upper body about the slewing central axis. The descent angle detection unit detects the descent angle of the undulating body about the rotation central axis. The rope length information acquisition unit acquires rope length information, which is information corresponding to the length of the load rope between the undulating body tip and the load. The movement information reception unit accepts movement information including a target slewing angle for moving the load about the slewing central axis by the slewing operation of the upper body from an initial state in which the load is lifted by the slewing rope to a predetermined target position.If the angle of the load rope relative to the vertical direction when the hoisting body is viewed along the rotation direction of the upper body is defined as the radial sway angle, and the angle of the load rope relative to the vertical direction when the hoisting body is viewed along the radial direction of the rotation motion of the upper body is defined as the rotation direction sway angle, the target speed setting unit determines coefficients of the multiple monomials based on an equation of motion of the load for each of the rotation direction and the radial direction, which includes at least the length of the hoisting body, the length of the load rope, and the hoisting angle, and a polynomial function for the rotation angle of the upper body, with the elapsed time of the rotation motion as a variable, the polynomial function being composed of multiple monomials each having different orders for the elapsed time, so that the radial sway angle and the rotation direction sway angle at least at the target position and during the rotation motion are smaller than a predetermined threshold angle and the time it takes for the load to reach the target position is minimized, and sets a target speed according to the elapsed time of the upper body until it reaches the target position. The command signal generating unit generates and outputs the speed command signal corresponding to the target speed set by the target speed setting unit.

[0008] According to this configuration, the target speed setting unit can set the target speed of the upper body based on the equation of motion and polynomial function of the load so that the swing angle of the load in two directions at the target position or during rotation is smaller than the threshold angle and the arrival time of the load is minimized. Therefore, unlike the case where the required movement time is set in advance by the operator, the target speed of the upper body is not affected by the required movement time, and the load can be moved in the shortest possible movement time while satisfying the suppression of swing at the target position or during rotation. Therefore, it is possible to efficiently move the load to the target position while suppressing the swing of the load at the target position or during rotation.

[0009] In the above configuration, the command signal generating section may input the generated speed command signal to the turning drive section.

[0010] According to this configuration, the upper body can be automatically rotated based on the speed command signal generated by the command signal generating unit so as to move the suspended load to the target position while suppressing load sway at the target position.

[0011] In the above configuration, the target speed setting unit may determine coefficients of the plurality of monomials such that the radial wobble angle and the turning direction wobble angle at the target position are smaller than predetermined threshold angles.

[0012] In the above configuration, the target speed setting unit may further determine coefficients of the multiple monomials so that the rotation speed of the upper body is zero when the load reaches the target position, and the radial sway angular velocity and the rotational sway angular velocity, which are the time changes of the radial sway angle and the rotational sway angle, respectively, are equal to or less than a predetermined threshold angular velocity at the target position.

[0013] In the above configuration, the target speed setting unit may further determine coefficients of the plurality of monomials so that, during the turning operation, the moving speed of the upper body is equal to or less than a predetermined maximum speed, the radial sway angle and the turning direction sway angle are equal to or less than a predetermined maximum angle during movement, and the radial sway angular velocity and the turning direction sway angular velocity are equal to or less than a predetermined maximum angular velocity during movement.

[0014] In the above configuration, the target speed setting unit may set the target speed based on the following equations I and II as equations of motion of the suspended load. θ''1=2×θ'2×θ'4+θ2×θ''4+θ1×θ'4 2 +(L / l)×θ'4 2 ×sinθ3-(g / l)×θ1...(Formula I) θ''2=-(L / l)×θ''4×sinθ3-2×θ'1×θ'4-θ1×θ''4+θ2×θ'4 2 -(g / l)θ2 (Eq. II) (where θ1: radial swing angle of the load, θ2: rotational swing angle of the load, θ'1: radial swing angular velocity of the load, θ'2: rotational swing angular velocity of the load, θ''1: radial swing angular acceleration of the load, θ''2: rotational swing angular acceleration of the load, θ3: hoisting angle of the hoisting body relative to the vertical direction, θ'4: rotation angular velocity of the upper body, θ''4: rotation angular acceleration of the upper body, g: gravitational acceleration, L: length of the hoisting body, l: length of the load rope from the tip of the hoisting body to the load)

[0015] In the above configuration, the target speed setting unit may set the target speed based on the following equations III and IV as equations of motion of the suspended load. θ''1=2×θ'2×θ'4+(L / l)×θ'4 2 ×sinθ3-(g / l)×θ1...(Formula III) θ''2=-(L / l)×θ''4×sinθ3-(g / l)θ2...(Formula IV) (where θ1: radial swing angle of the load, θ2: rotational swing angle of the load, θ'2: rotational swing angular velocity of the load, θ''1: radial swing angular acceleration of the load, θ''2: rotational swing angular acceleration of the load, θ3: hoisting angle of the hoisting body relative to the vertical direction, θ'4: rotation angular velocity of the upper body, θ''4: rotation angular acceleration of the upper body, g: gravitational acceleration, L: length of the hoisting body, l: length of the load rope from the tip of the hoisting body to the load) Effect of the Invention

[0016] According to the present invention, there is provided a crane that can efficiently move a load to a target position while suppressing load swing at least either at the target position or during a swing operation. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a side view of a crane according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic perspective view for explaining a swing control of a crane according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a block diagram of a crane according to an embodiment of the present invention. [Figure 4] 4 is a flowchart of a swing control of a crane according to an embodiment of the present invention. [Diagram 5] 1 is an example of an upper body rotation speed profile. [Figure 6] 11 is a graph showing a time progression of a radial runout angle in an embodiment of the present invention. [Figure 7] 11 is a graph showing a transition of a turning direction shake angle over time in an embodiment of the present invention. [Figure 8] 4 is a graph showing a transition of a turning angle over time in an embodiment of the present invention. [Figure 9] 4 is a graph showing a time progression of a turning angular velocity in an embodiment of the present invention. [Figure 10] 11 is a graph showing a time progression of a radial runout angle in an embodiment of the present invention. [Figure 11] 11 is a graph showing a transition of a turning direction shake angle over time in an embodiment of the present invention. [Figure 12] 4 is a graph showing a time progression of a turning torque in an embodiment of the present invention. [Figure 13] 4 is a graph showing a transition of a turning angle over time in an embodiment of the present invention. [Figure 14] 4 is a graph showing a time progression of a turning angular velocity in an embodiment of the present invention. [Figure 15] 4 is a graph showing a transition of a turning angle over time in an embodiment of the present invention. [Figure 16] 4 is a graph showing a time progression of a turning angular velocity in an embodiment of the present invention. [Figure 17] 11 is a graph showing a time progression of a radial runout angle in an embodiment of the present invention. [Figure 18] 11 is a graph showing a time transition of a radial shake angular velocity in an embodiment of the present invention. [Figure 19] 11 is a graph showing a transition of a turning direction shake angle over time in an embodiment of the present invention. [Figure 20]11 is a graph showing a time transition of a turning direction shake angular velocity in an embodiment of the present invention. [Figure 21] 11 is a graph showing a time progression of a radial runout angle in an embodiment of the present invention. [Figure 22] 11 is a graph showing a time transition of a radial shake angular velocity in an embodiment of the present invention. [Diagram 23] 11 is a graph showing a transition of a turning direction shake angle over time in an embodiment of the present invention. [Figure 24] 11 is a graph showing a time transition of a turning direction shake angular velocity in an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a side view of a crane 10 according to this embodiment. Note that although Fig. 1 shows the directions of "up", "down", "front" and "rear", these directions are shown for the sake of convenience in explaining the structure of the crane 10 according to this embodiment and the swing control described below, and do not limit the movement direction or usage mode of the crane according to the present invention.

[0019] The crane 10 comprises a running body 14 (lower body), a rotating body 12 (upper body) supported on the running body 14 so as to be rotatable about a central axis of rotation extending in the vertical direction, a boom 16 (hoisting body), and a mast 20. A counterweight 13 for adjusting the balance of the crane 10 is loaded on the rear of the rotating body 12. A cab 15 is provided on the front end of the rotating body 12. The cab 15 corresponds to the driver's seat of the crane 10.

[0020] The boom 16 shown in FIG. 1 is a so-called lattice type, and is composed of a lower boom 16A (base end of the hoisting body), one or more (three in the illustrated example) intermediate booms 16B, 16C, 16D, and an upper boom 16E (tip end of the hoisting body opposite to the base end of the hoisting body). Specifically, the lower boom 16A is supported on the front of the revolving body 12 so as to be rotatable in the hoisting direction around a horizontal rotation center axis (first rotation center axis). The intermediate booms 16B, 16C, 16D are removably attached to the tip end of the lower boom 16A in that order. The upper boom 16E is removably attached to the tip end of the intermediate boom 16D. The lower boom 16A is rotatably supported on the revolving body 12 at a boom foot pin 16S provided at the lower end thereof.

[0021] The boom 16 also has idler sheaves 34S, 36S. The idler sheaves 34S, 36S are each rotatably supported on the rear side of the lower boom 16A.

[0022] However, the present invention is not limited to a specific boom structure. For example, the boom may not have an intermediate member, or may have a different number of intermediate members from the above. Furthermore, the boom may be composed of a single member.

[0023] The mast 20 has a base end and a rotating end, and the base end is rotatably connected to the rotating body 12. The rotation axis of the mast 20 is parallel to the rotation axis of the boom 16 and is located immediately rearward of the rotation axis of the boom 16. In other words, the mast 20 is rotatable in the same direction as the direction in which the boom 16 is raised and lowered.

[0024] Furthermore, the crane 10 is equipped with a pair of left and right boom backstops 23 and a pair of left and right boom guylines 24.

[0025] A pair of left and right boom backstops 23 are provided on both the left and right sides of the lower boom 16A of the boom 16. These boom backstops 23 come into contact with the center in the fore-and-aft direction of the rotating body 12 when the boom 16 reaches the upright position shown in Fig. 1. This contact prevents the boom 16 from being blown backward by strong winds or the like.

[0026] A pair of left and right boom guylines 24 connect the rotating end of the mast 20 to the tip of the boom 16. This connection coordinates the rotation of the mast 20 and the rotation of the boom 16.

[0027] The crane 10 further includes various winches. Specifically, the crane 10 includes a boom hoist winch 30 for raising and lowering the boom 16, a main winch 34 and an auxiliary winch 36 for hoisting and lowering a load. The crane 10 also includes a boom hoist rope 38, a main hoisting rope 50 (suspension rope) that hangs down from the tip of the boom 16 and is connected to the load, and an auxiliary rope 60. In the crane 10 according to this embodiment, the main winch 34 and the auxiliary winch 36 are installed near the base end of the boom 16. The boom hoist winch 30 is installed on the rotating body 12. The positions of these winches 30, 32, 34, 36 are not limited to those described above.

[0028] The boom hoist winch 30 winds and pays out the boom hoist rope 38. The boom hoist rope 38 is arranged so that the mast 20 rotates as a result of this winding and paying out. Specifically, sheave blocks 40, 42, in which a plurality of sheaves are arranged in the width direction, are provided at the rotating end of the mast 20 and the rear end of the rotating body 12, respectively, and the boom hoist rope 38 drawn out from the boom hoist winch 30 is stretched between the sheave blocks 40, 42. Therefore, as the boom hoist winch 30 winds and pays out the boom hoist rope 38, the distance between the two sheave blocks 40, 42 changes, and as a result, the mast 20 and the boom 16 linked thereto rotate in the hoisting direction.

[0029] The main winch 34 hoists and lowers a load using a main hoisting rope 50. The main hoisting rope 50 (load rope) hangs down from the tip of the boom 16 and is connected to the load. A main hoisting guide sheave 54 is disposed at the tip of the boom 16, and a main hoisting sheave block is provided adjacent to the main hoisting guide sheave 54, in which multiple main hoisting point sheaves 56 are arranged in the width direction. The main hoisting rope 50 pulled out from the main hoisting winch 34 is hung in this order around the idler sheave 34S and the main hoisting guide sheave 54, and is also hung between the main hoisting point sheave 56 of the sheave block and a sheave 58 of a sheave block provided on a main hook 57 for hoisting a load. Therefore, when the main hoisting winch 34 winds or unwinds the main hoisting rope 50, the distance between the two sheaves 56, 58 changes, and the main hook 57 connected to the main hoisting rope 50 suspended from the tip of the boom 16 is hoisted up or down. As a result, the load can be hoisted up or down.

[0030] Similarly, the auxiliary winch 36 hoists and lowers the load using the auxiliary hoisting rope 60. For this auxiliary hoisting, an auxiliary hoisting guide sheave 64 is rotatably mounted coaxially with the main hoisting guide sheave 54, and an auxiliary hoisting point sheave (not shown) is rotatably mounted adjacent to the auxiliary hoisting guide sheave 64. The auxiliary hoisting rope 60 pulled out from the auxiliary hoisting winch 36 is hung in turn around the idler sheave 36S and the auxiliary hoisting guide sheave 64, and is suspended from the auxiliary hoisting point sheave. Therefore, when the auxiliary hoisting winch 36 winds or unwinds the auxiliary hoisting rope 60, an auxiliary hook for a suspended load (not shown) connected to the end of the auxiliary hoisting rope 60 is wound up or lowered.

[0031] Fig. 2 is a schematic perspective view for explaining the rotation control of the crane 10 according to this embodiment. Fig. 3 is a block diagram of the crane 10 according to this embodiment.

[0032] For the sake of explanation, in Fig. 2, the base end of the boom 16 is shown as being located on the central axis of rotation of the rotating body 12. In Fig. 2, L is the length of the boom 16, and l (lower case L) is the length of the main hoisting rope 50 suspended from the tip of the boom 16 to the load LM. Additionally, angles θ1 and θ2 indicate the load swing angles of the load LM. Specifically, angle θ1 is This is the angle of the main hoisting rope 50 relative to the vertical direction when the boom 16 is viewed along the rotation direction of the rotating body 12, and is called the radial swing angle θ1 (swing angle on the normal plane). On the other hand, angle θ2 is the angle of the main hoisting rope 50 relative to the vertical direction when the boom 16 is viewed along the radial direction of the rotational movement of the rotating body 12, and is called the rotational direction swing angle θ2 (swing angle on the tangential plane). Depending on the swinging movement of the load LM, the radial swing angle θ1 and the rotational direction swing angle θ2 can take not only positive values ​​but also negative values.

[0033] Angle θ4 is the rotation angle of the rotating body 12 about the rotation central axis, and angle θ3 is the elevation angle of the boom 16 about the rotation central axis, and they are shown with the vertical direction as the reference in Fig. 2. In addition, in the coordinate system in Fig. 2, the base end of the boom 16 is the origin, a predetermined horizontal direction (for example, the forward direction of the traveling body 14) is the X-axis, a horizontal direction perpendicular to the X-axis is the Y-axis, and a direction perpendicular to both the X-axis and the Y-axis (vertical direction) is the Z-axis.

[0034] In this embodiment, as shown in FIG. 2, when a load LM suspended from the tip of the boom 16 (elevating body) is rotated by the rotational movement of the rotating body 12 (change in rotation angle θ4), it is possible to move the load LM to the target position as quickly as possible while suppressing the swing of the load LM at the target position.

[0035] Referring to Figure 3, the crane 10 further includes a control unit 70, a slewing drive unit 71, a boom drive unit 72, a winch drive unit 73, a slewing operation unit 74, a boom operation unit 75, a winch operation unit 76, an input unit 81 (movement information receiving unit), a slewing angle detection unit 82, a boom hoisting angle detection unit 83, a rope length detection unit 84 (rope length information acquisition unit), a boom length acquisition unit 85 (boom length information acquisition unit), a suspended load detection unit 86, and a display unit 87.

[0036] The slewing drive unit 71 is capable of receiving a predetermined speed command signal and rotating the rotating body 12 around the slewing central axis at a speed corresponding to the speed command signal. Specifically, the slewing drive unit 71 generates a driving force capable of rotating the rotating body 12 around the slewing central axis in a first slewing direction and a second slewing direction opposite to the first slewing direction. The slewing drive unit 71 includes a hydraulic slewing motor that receives a supply of hydraulic oil to rotate the rotating body 12.

[0037] The boom drive unit 72 generates a driving force for rotating the boom hoist winch 30 and is capable of rotating the boom 16 about the central axis of rotation. The boom drive unit 72 includes a hydraulic hoist motor that rotates the boom hoist winch 30 by receiving a supply of hydraulic oil.

[0038] The winch drive unit 73 generates a drive force for rotating the main winch 34, and the main winch 34 winds and unwinds the main hoisting rope 50, making it possible to raise and lower the load LM relative to the ground. The winch drive unit 73 includes a hydraulic load motor that receives a supply of hydraulic oil to rotate the main winch 34. A winch drive unit (not shown) for rotating the auxiliary winch 36 is also provided in the same manner.

[0039] The slewing operation unit 74, the boom operation unit 75 and the winch operation unit 76 are disposed within the cab 15, and receive operations for driving each member of the crane 10 by the operator.

[0040] The turning operation unit 74 receives an operation for turning the turning body 12 by the turning drive unit 71. The turning operation unit 74 is switchable between a turning position for turning the turning body 12 in each of the first turning direction and the second turning direction and a neutral position for stopping the turning of the turning body 12.

[0041] The boom operation unit 75 receives operations for raising and lowering the boom 16 by the boom drive unit 72. The boom operation unit 75 is switchable between a hoisting position for raising and lowering the boom 16 and a neutral position for stopping the raising and lowering of the boom 16. In the hoisting position, operation in an upright direction for raising the boom 16 and in a lowering direction for lowering the boom 16 is possible.

[0042] The winch operation unit 76 accepts operations for raising and lowering the load LM by the winch drive unit 73. The winch operation unit 76 is switchable between a lifting position for lifting and lowering the load LM and a neutral position for stopping the lifting and lowering of the load LM. In the lifting and lowering position, operation in an upward direction for lifting the load LM and in a downward direction for lowering the load LM is possible.

[0043] The input unit 81 is disposed in the cab 15, and receives input of information related to the control of the crane 10 by an operator. As an example, the input unit 81 includes a touch panel type input device and various switches, buttons, etc. The input unit 81 receives a target slewing angle θ for moving the load LM from an initial state in which the load LM is hoisted by the main hoisting rope 50 to a predetermined target position by the slewing operation of the slewing body 12 about the slewing central axis. f4 The movement information including the above is accepted.

[0044] The rotation angle detection unit 82 detects and outputs a rotation angle θ4 around the central axis of rotation of the rotating structure 12 (boom 16). The rotation angle detection unit 82 includes a gyro sensor (IMU sensor) and a calculation unit (not shown). The rotation angle detection unit 82 measures the angular velocity around the central axis of rotation of the rotating structure 12 using the gyro sensor, and the calculation unit converts the measured angular velocity into an angle by integrating it once with respect to time, and outputs the angle as the rotation angle θ4. Note that the structure of the rotation angle detection unit 82 is not limited to the above, and may be a known angle meter, encoder, etc.

[0045] The hoisting angle detection unit 83 detects and outputs the hoisting angle θ3 around the central axis of rotation of the boom 16. The hoisting angle detection unit 83 is made of an inclination sensor and detects the relative angle of the boom 16 with respect to the vertical direction. The hoisting angle detection unit 83 may also detect the relative angle with respect to other objects. For example, the hoisting angle detection unit 83 may detect the ground angle of the boom 16 (the relative angle with respect to the horizontal direction) and calculate and output the hoisting angle θ3 by subtracting the ground angle from 90 degrees. The hoisting angle detection unit 83 may also be a known goniometer.

[0046] The rope length detection unit 84 acquires and outputs rope length information which is information corresponding to the length (l) of the main hoisting rope 50 between the tip of the boom 16 and the load LM. In this embodiment, the distance between the main winding point sheave 56 at the tip of the boom 16 and the main hook 57 (sheave 58) is detected as the rope length. The rope length detection unit 84 includes a rotation amount detection unit capable of detecting the amount of rotation of the main winding winch 34, and a winding layer detection unit which detects the number of winding layers of the main hoisting rope 50 on the outer circumferential surface of the main winding winch 34. The rope length detection unit 84 calculates and outputs the distance from the winch diameter of the main winding winch 34, the winch rotation amount detected by the rotation amount detection unit, as well as the amount of the main winding rope 50 let out from the main winding winch 34 estimated from the winding layers of the main winding rope 50 detected by the winding layer detection unit, and the number of loops of the main winding rope 50 between the main winding point sheave 56 and the sheave block of the sheave 58.

[0047] The method of detecting the length l of the main hoisting rope 50 is not limited to the above embodiment. For example, the rope length may be detected by clamping the wire with a sheave (not shown) and measuring the rotation of the sheave with an encoder, or the load may be detected by measuring the area below the tip of the boom 16 (boom top) in real time with a 3D LIDAR, and the rope length may be calculated by measuring the distance from the boom top to the load. Also, the distance to the load may be measured using a known stereo camera or sound waves, and the rope length may be calculated. In this case, the reference point for distance measurement may be any part of the boom such as the boom top, the crane body, the ground other than the crane, etc. Furthermore, the rope length may be calculated by attaching a sensor capable of measuring the position such as a GPS to the load.

[0048] The boom length acquisition unit 85 acquires information on the length (L) of the boom 16 used in the rotation control of the revolving body 12 executed by the control unit 70. That is, the boom length acquisition unit 85 acquires and outputs information (hoisting body length information) corresponding to the length of the boom 16 in the boom longitudinal direction (hoisting body longitudinal direction), which is the direction connecting the base end (hoisting body base end) and the tip end (hoisting body tip end) of the boom 16. The boom length acquisition unit 85 may be a storage unit that stores the length of the boom 16 when the crane 10 is manufactured, or may be an input unit that receives information on the length of the boom 16 from an operator. For this reason, the function of the boom length acquisition unit 85 may be performed by the storage unit 704 or the input unit 81 of the control unit 70 in FIG. 3. Furthermore, when multiple booms 16 of different lengths are selectively attached to the revolving body 12, the boom length acquisition unit 85 may be a receiving unit that receives information on the length of the boom 16 from an RFID or the like attached to each boom 16.

[0049] The suspended load detection unit 86 acquires and outputs information (suspended load information) relating to the weight of the suspended load LM connected to the main hook 57. In this embodiment, the suspended load detection unit 86 includes a load detector (load cell) (not shown) connected to the main hoisting rope 50, and detects the weight of the suspended load LM based on a change in the strain of the tension of the main hoisting rope 50. Note that in other embodiments, the pressure in the hydraulic circuit that raises and lowers the boom 16 may be detected by a pressure gauge (not shown), and the load of the suspended load may be estimated based on the pressure.

[0050] The display unit 87 is a display disposed inside the cab 15, and displays various types of information to be notified to the operator.

[0051] The control unit 70 is composed of a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores a control program, a RAM (Random Access Memory) used as a working area for the CPU, etc. The control unit 70 functions to include a drive control unit 701, a target speed calculation unit 702 (target speed setting unit), a command signal generation unit 703, and a storage unit 704 by the CPU executing the control program stored in the ROM.

[0052] The drive control unit 701 inputs command signals corresponding to the operation direction and operation amount received by the rotation operation unit 74, boom operation unit 75 and winch operation unit 76 to the rotation drive unit 71, boom drive unit 72 and winch drive unit 73, respectively, to drive each drive unit.

[0053] The target speed calculation unit 702 sets a target speed of the rotating body 12 until the load LM reaches the target position when the automatic rotation control is executed. Note that the automatic rotation control is a control for automatically moving the load LM in the rotation direction from a predetermined initial position to the target position.

[0054] The command signal generating unit 703 generates and outputs a speed command signal corresponding to the target speed set by the target speed calculating unit 702. The speed command signal output by the command signal generating unit 703 is input to the revolving drive unit 71. As a result, the revolving operation of the revolving body 12 is automatically controlled. Note that in another embodiment, the speed command signal may be input to the display unit 87, and the operator may operate the revolving operation unit 74 according to the magnitude and direction of the speed command signal (revolving assist).

[0055] The memory unit 704 stores parameters, threshold values, etc. that are referenced during various controls executed in the crane 10.

[0056] <Turning control flow> 4 is a flowchart of the rotation control of the crane 10 according to this embodiment. When the control unit 70 executes automatic control of the rotation operation, the control unit 70 first judges whether or not the automatic control switch included in the input unit 81 is turned on (step S1). Here, if the automatic control switch is turned on (YES in step S1), the control unit 70 judges whether or not movement information is stored in the memory unit 704 (step S2). As described above, the movement information includes a target rotation angle θ to a target position to which the load LM is to be moved. f4 The operator inputs the information through the input unit 81 and the information is stored in the storage unit 704.

[0057] If there is movement information in step S2 (YES in step S2), the swivel angle detection unit 82, the hoisting angle detection unit 83, and the rope length detection unit 84 respectively detect the swivel angle θ4, the hoisting angle θ3, and the length l of the main hoisting rope 50 (step S3). The detected information is stored in the memory unit 704. If the automatic control switch is OFF in step S1 (NO in step S1) or if there is no movement information in step S2 (NO in step S2), each process is repeated as shown in FIG. 2.

[0058] When each piece of information is detected in step S3, the boom length acquisition unit 85 acquires the length (L) of the boom 16. As described above, the length of the boom 16 may be stored in advance in the storage unit 704, or may be input via the input unit 81 or the like.

[0059] Next, the target speed calculation unit 702 calculates the profile (change) of the rotation speed (rotation angular velocity θ'4) of the rotating body 12 while the load LM moves from the initial position to the target position (step S5). That is, in this embodiment, in order to suppress load swing of the load LM, the angular velocity θ'4 is controlled to change according to the rotation angle θ4 of the rotating body 12. Note that in the following explanation, the derivative of θ (angular velocity) may be represented as θ', and the second derivative of θ (angular acceleration) may be represented as θ''. The change in the calculated rotation angular velocity θ'4 is displayed on the display unit 87 so that the operator can check it.

[0060] When the speed profile (change in angular speed θ'4) is determined in step S5, the target speed calculation unit 702 calculates an estimated load sway amount of the load LM at the target position in step S6. At this time, the radial sway angle θ1 and the rotational sway angle θ2 of the load LM are calculated from the above-mentioned equation of motion, and the results are displayed on the display unit 87.

[0061] Next, the command signal generating unit 703 generates a speed command signal according to the calculated angular velocity θ'4 (step S7) and inputs it to the revolving drive unit 71. As a result, the revolving drive unit 71 revolves the revolving body 12, and automatic control of the revolving operation of the revolving body 12 is executed (step S8).

[0062] <About turning speed calculation> Next, the calculation of the turning velocity (angular velocity θ′4) executed in step S5 above will be described in detail.

[0063] When the rotating body 12 rotates toward the target position from a state in which the load LM is lifted by the boom 16 in the initial position, two-dimensional load swing occurs in the radial direction and the rotation direction of the load LM connected to the main hoisting rope 50. In addition to the horizontal movement of the boom 16 rotating together with the rotating body 12, the boom 16 can also move vertically by rising and falling. Therefore, in order to suppress the above-mentioned two-dimensional load swing, it is also possible to adjust the hoisting angle θ3 of the boom 16 during movement in addition to the rotation speed (angular velocity θ'4) of the rotating body 12. However, since such vertical movement of the load LM goes against gravity, it is likely to cause more complicated load swing, and it becomes difficult to suppress the load swing while causing the load LM to reach the target position in a short time.

[0064] Therefore, in this embodiment, the control unit 70 determines the optimal trajectory in time by only rotating the rotating body 12, i.e., by moving the boom 16 in the horizontal direction, and suppresses load sway at the target position. In other words, the hoisting angle θ3 of the boom 16 is fixed during this rotating movement. Moreover, the trajectory here includes not only a positional trajectory but also a time element, and includes the question of which position the load LM will pass at each time. Furthermore, the control unit 70 suppresses continuous load sway of the load LM after it reaches the target position as much as possible.

[0065] If the torque applied to a rotation motor (not shown) included in the rotation drive unit 71 that drives the rotating body 12 is denoted as τ4, the torque τ4 can be expressed by the following formula 1 based on the Lagrange equation of motion and the like.

number

[0066] The definitions of some of the parameters included in the above formula 1 and each formula below are shown in Table 1 below. [Table 1]

[0067] Regarding the parameters in Equation 1, J4 and I b is the moment of inertia acting on the rotating bed 12 and the boom 16. x , I y , I z As shown in Table 1, is the moment of inertia acting on the boom 16 around each coordinate axis.

[0068] Here, from the balance of external forces acting on the suspended load LM in FIG. 2, a dynamics model of the load swing of the suspended load LM in each of the radial and rotational directions can be expressed based on dynamics by the following Equations 2 and 3.

number

number

[0069] In Equation 2 and Equation 3, g is the acceleration due to gravity. Equation 2 and Equation 3 are defined as a reference (complete) dynamics model that represents the load swing of the suspended load LM. Meanwhile, in Equation 2 and Equation 3, the product of the square of θ and the second derivative of θ, as well as the product of θ and the square of the first derivative of θ, are relatively small values ​​and can therefore be omitted (θ includes θ1 and θ2). For this reason, Equation 2 and Equation 3 can be replaced with the following Equation 4 and Equation 5.

number

number

[0070] Equations 4 and 5 are defined as a first dynamics model expressing the load swing of the suspended load LM. Moreover, equations 4 and 5 correspond to equations I and II of the present invention. Furthermore, by omitting the second and third terms on the right side of the above equation 4, and the second, third and fourth terms on the right side of equation 5, the following equations 6 and 7 can be obtained.

number

number

[0071] Equations 6 and 7 are defined as a second dynamics model expressing the swing of the suspended load LM. Moreover, equations 6 and 7 correspond to equations III and IV of the present invention. Furthermore, in this embodiment, in order to simplify the dynamic movement of the boom 16 and generate an optimal time trajectory, the target speed calculation unit 702 defines the rotation angle θ4 of the rotating body 12 by a polynomial function with the elapsed time t of the rotation operation based on the initial position (start point of the rotation operation) as a variable, as shown in the following equation 8.

number

[0072] As shown in Equation 8, in this embodiment, the movement of the boom 16 is formulated using a sixth-order polynomial as a model for simplifying the movement of the boom 16. i (i=1 to 6) are polynomial coefficients determined by optimization. However, in the initial state when the rotation operation of the rotating body 12 starts, the rotation angle θ4=0 and the rotation angular velocity θ'4=0, so the coefficients b0 and b1 are assigned to zero. Therefore, five coefficients b2, b3, b4, b5, and b6 are adjusted by optimization. Note that the degree of the polynomial is not limited to sixth degree, and a lower or higher degree polynomial may be used.

[0073] Here, if the time when the load LM reaches the target position is T, the time (elapsed time) t during the rotation operation can be expressed as t = ST. S is a vector including discrete values ​​within the range of 0 ≦ S ≦ 1. As a result, Equation 8 can be expressed as Equation 9 below.

number

[0074] The target speed calculation unit 702 calculates the polynomial coefficient b so that the arrival time T in the above formula 9 is minimized. iBy setting (i=2 to 6), respectively, the load LM can be moved quickly to the target position. At this time, in order to suppress the swing of the load LM, it is desirable that the radial swing angle θ1 and the rotational swing angle θ2 defined in the above-mentioned formulas 4 and 5 or formulas 6 and 7 are suppressed to a predetermined threshold angle or less at the target position, and are also suppressed to a predetermined maximum angle or less during movement to the target position. Therefore, the above problem can be expressed by the following formulas 10 and 11.

number

number

[0075] Equation 10 is the polynomial coefficient b that minimizes the arrival time T. i (i=2 to 6), and Equation 11 represents the conditions for this. Looking at Equation 11 from top to bottom, the turning angle θ4(T) at time T is the target turning angle θ f4 At time T, i.e., at the target position, the rotation angular velocity θ'4(T) is zero. The absolute value of the rotation angular velocity θ'4(t) (velocity) during movement is equal to or less than the maximum rotation angular velocity θ' max4 (maximum speed) or less. Furthermore, the swing angle θ i The absolute value of (T) (i=1, 2) is the preset final load swing allowable angle θ f (threshold angle) or less. Similarly, the shake angular velocity θ′ at the target position i The absolute value of (T) (i=1, 2) is the preset final allowable load swing angular velocity θ' f (threshold angular velocity) or less. Also, the shake angle θ i The absolute value of (t) (i=1, 2) is the preset allowable load swing angle θ SW (Maximum angle during movement) or less. Similarly, the angular velocity θ' during movement i The absolute value of (t) (i=1, 2) is the preset allowable angular velocity θ' SW(Maximum angular velocity during movement) or less. The above parameters are also shown in Table 1. Each angular velocity corresponds to the change in the corresponding angle over time.

[0076] In this embodiment, the target speed calculation unit 702 calculates the above problem by sequential quadratic programming as an example. The target speed calculation unit 702 can calculate an optimal solution by the above-mentioned formulas 4, 5, 9, 10, and 11 (Example 2 described later) or formulas 6, 7, 9, 10, and 11 (Example 1 described later) according to the calculation accuracy and calculation time required at the work site. By this calculation, the polynomial coefficient b i When each of (i=2 to 6) is optimized and the minimum arrival time T of equation 10 is determined, the predicted arrival time may be displayed on display unit 87. Furthermore, target speed calculation unit 702 determines the transition of turning angle θ4 at each time during movement from equation 9, and determines the transition of turning angular velocity θ'4 from its derivative. From this result, command signal generation unit 703 can generate a speed command signal in the previous step S7.

[0077] On the other hand, the target speed calculation unit 702 can calculate the radial shake angle θ1 and the turning direction shake angle θ2 at the target position from the optimization result described above using Equation 4 and Equation 5, or Equation 6 and Equation 7 (step S6 in FIG. 4). At this time, the target speed calculation unit 702 may calculate the radial shake angle θ1 and the turning direction shake angle θ2 from Equation 2 and Equation 3.

[0078] As described above, in this embodiment, the target speed calculation unit 702 calculates the target speed (angular speed θ'4) of the rotating structure 12 based on the equation of motion of the load LM based on dynamics and a predetermined polynomial function. The equation of motion includes at least the length L of the boom 16, the length l of the main hoisting rope 50, and the hoisting angle θ3, and includes equations for both the rotation direction and the radial direction. In addition, the polynomial function is a polynomial function for the rotation angle θ4 of the rotating structure 12 with the elapsed time t of the rotation operation based on the initial position as a variable. The polynomial function is made up of a plurality of monomials each including a different order for the elapsed time t. Based on these equations and functions, the target speed calculation unit 702 determines the coefficients of the multiple monomials so that the radial sway angle θ1 and the rotational sway angle θ2 at the target position are smaller than predetermined threshold angles and the time T at which the load LM reaches the target position is minimized, thereby setting a target speed (angular speed θ'4) that corresponds to the elapsed time t of the rotating body 12 until it reaches the target position.

[0079] In particular, in this embodiment, the target speed calculation unit 702 can set the target speed of the rotating body 12 based on the equation of motion of the load LM and a polynomial function so that the sway angles θ1, θ2 of the load LM in two directions at the target position are smaller than predetermined threshold angles and the arrival time of the load LM is minimized. Therefore, unlike in the case where the required movement time is set in advance, the target speed of the rotating body 12 is not affected by the required movement time, and the load LM can be moved in the shortest possible movement time while suppressing load swing at the target position. Therefore, it is possible to efficiently move the load LM to the target position while suppressing load swing of the load LM at the target position.

[0080] Also, in this embodiment, the target speed (change in angular velocity) of the rotating body 12 can be optimized so that the arrival time of the load LM is minimized. In this case, the conditions for optimizing this problem already include the load swing constraint condition of the load LM. Therefore, compared to the conventional case where the above-mentioned conveying speed is corrected to suppress load swing by applying a filter process (target value filter) based on inverse dynamics to the transition of the conveying speed once set, it is possible to set an optimal target speed of the rotating body 12 in response to a wide range of conditions. Also, compared to the case where the conveying time to the target value is set in advance, the target speed of the rotating body 12 is not restricted by the conveying time, and it is possible to make the load LM reach the target position in the minimum time while always suppressing the load swing.

[0081] Furthermore, in this embodiment, the calculation performed by the target speed calculation unit 702 uses an equation of motion for the load LM that includes the length of the main hoisting rope 50 (position of the main hook 57), the hoisting angle θ3 of the boom 16, and the length of the boom 16 (turning radius), so that the load LM can be moved to the target position in a short period of time while suppressing the sway of the load LM with high accuracy.

[0082] Furthermore, when the first dynamics model out of the two dynamics models described above is used to optimize the rotation angular velocity θ'4 in the rotation operation of the rotating body 12, it is possible to make the load LM reach the target position in the shortest time possible, and it is possible to suppress the sway of the load LM while maintaining a high degree of coincidence of the waveform with the complete dynamics model (full model). EXAMPLES

[0083] The present invention will now be described in more detail with reference to examples, although the present invention is not limited to the following examples.

[0084] <Verification of simplified dynamics model> As described above, in order to calculate a swing speed that satisfies a predetermined condition in the swing control of the crane 10, the target speed calculation unit 702 employs the first dynamics model (Equation 4, Equation 5) or the second dynamics model (Equation 6, Equation 7). These are simplifications of the complete dynamics model (Equation 2, Equation 3), so their effectiveness will be verified. FIG. 5 is an example of a basic swing speed profile (cycloid boom speed). FIG. 6 is a graph showing the time transition of the radial swing angle θ1 in an embodiment of the present invention. FIG. 7 is a graph showing the time transition of the swing angle θ2 in the swing direction in an embodiment of the present invention.

[0085] The relationship between time and the turning angular velocity in FIG. 5 can be expressed by the following Equation 12.

number

[0086] In addition, θ' in Equation 12 max4 corresponds to the maximum angular velocity in FIG. 5. The time 20 sec in FIG. 5 is assumed to be the target position. In such a velocity profile, not only the velocity (angular velocity) but also the acceleration (angular acceleration) at the target position is zero. Along with such a velocity profile, the conditions shown in Table 2 below are input to the first dynamics model (Example 2), the second dynamics model (Example 1), and the complete dynamics model (reference example), and the transitions of the radial shake angle θ1 and the turning direction shake angle θ2 are shown in FIG. 6 and FIG. 7. Note that under each condition, the velocity and acceleration are calculated at a sampling time of 10 msec. [Table 2]

[0087] 6 and 7, the first dynamics model (Equation 4, Equation 5) was found to match the complete dynamics model at both the radial sway angle θ1 and the turning direction sway angle θ2. On the other hand, the second dynamics model, which omitted more terms than the first dynamics model, was found to approximate the complete dynamics model at the radial sway angle θ1, but was found to deviate from the complete dynamics model in the latter half of the time range at the turning direction sway angle θ2. Therefore, in terms of matching with the complete dynamics model, the first dynamics model produced better results.

[0088] <Load swing constraints> As described above, in the present invention, the transition of the rotation speed is optimized so that the load LM reaches the target position in the shortest time and the load sway at the target position and during movement is kept below a predetermined threshold angle (load sway constraint condition). For this reason, the movement of the load LM with and without this load sway constraint condition was evaluated. In this evaluation, the hoisting angle θ3 was assumed to be 45 degrees, and the other conditions are shown in Table 3 below. [Table 3]

[0089] Based on the above conditions, the target position (target turning angle θ f4) are shown in Figs. 8 and 9, respectively. In Figs. 8 and 9, "With sway" is the calculation result when all the constraints of Equation 11 are taken into account (similar to the figures described later). On the other hand, in Figs. 8 and 9, "No sway" corresponds to the calculation result when there are no constraints (load swing constraints) related to the lower four radial sway angles θ1 and sway sway angles θ2 of Equation 11 (similar to the figures described later). As shown in Fig. 8, when there are no load swing constraints, the load LM reaches the target position earlier than when there are load swing constraints. However, in this case, as shown in Fig. 9, the sway angular velocity θ'4 of the rotating body 12 rises sharply from the start of rotation and then drops sharply just before the target position. For each of the above calculations, the calculation time until the optimization is completed was 1.50 seconds for "No sway" and 2.99 seconds for "With sway".

[0090] Furthermore, in order to confirm the validity of the time-optimized trajectory generated as described above, the transitions of the radial sway angle θ1 and the turning direction sway angle θ2 of the suspended load LM were calculated by applying Equation 9 to Equation 2 and Equation 3. Fig. 10 is a graph showing the transition of the radial sway angle over time in this embodiment. Fig. 11 is a graph showing the transition of the turning direction sway angle over time in this embodiment. Note that both graphs in Fig. 10 and Fig. 11 also show the load sway after the suspended load LM has reached the target position (see the arrival time in Fig. 8).

[0091] As shown in Figures 10 and 11, when there are load sway constraints, the load sway during movement, at the target position, and after reaching the target position is kept low for both the radial sway angle θ1 and the rotational sway angle θ2. On the other hand, when there are no load sway constraints, as shown in Figure 9, although the suspended load LM reaches the target position quickly, there are results in which large load sway occurs during movement, at the target position, and after reaching the target position.

[0092] Furthermore, by applying the above calculation results to Equation 1, the torque of the swing motor that swings the swing body 12 was evaluated with and without the load swing constraint. FIG. 12 is a graph showing the time transition of the swing torque τ4 in this embodiment. In FIG. 12, a part of the torque transition is partially enlarged. As shown in FIG. 12, in both cases with and without the load swing constraint, the result is that the torque falls within the range between the maximum torque and minimum torque of the swing motor that are preset in the crane 10 (the dashed lines at the top and bottom of FIG. 12). It should be noted that by using the above-mentioned Equation 1 as the constraint, it is also possible to generate a polynomial trajectory that limits the swing torque τ4 between the maximum torque and the minimum torque.

[0093] <Verification results of load swing suppression> Next, the results of optimization calculations performed on the above-mentioned first dynamics model (Example 2) and second dynamics model (Example 1) in two cases of the constraint conditions included in formula 11 are shown. Table 4 shows two cases (Case 1 and Case 2) of the above constraint conditions. [Table 4]

[0094] In case 2, the maximum turning angular velocity θ' is max4 , allowable angular velocity of load swing during movement θ' SW , Final load swing allowable angle θ f is set relatively large, while the final load swing allowable angular velocity θ' f is set to be relatively small. Figures 13 and 14 are graphs showing the transition of the turning angle θ4 and the turning angular velocity θ'4 over time in the above-mentioned Case 1. In Case 1, there is no significant difference in the transition of the turning angle θ4 between Example 1 and Example 2, but the transition of the turning angular velocity θ'4 is more gradual in Example 2, which results in the reduction of the top speed.

[0095] 15 and 16 are graphs showing the time progression of the turning angle θ4 and the turning angular velocity θ'4 in the above-mentioned Case 2. In Case 2, the result is that Example 2 reaches the target position earlier than Example 1. Although there is a difference in the arrival time as mentioned above, no large difference is seen in the profile of the turning angular velocity θ'4.

[0096] 17, 18, 19, and 20 are graphs showing the time transitions of the radial sway angle θ1, the radial sway angular velocity θ'1, the swing direction sway angle θ2, and the swing direction sway angular velocity θ'2 in the above-mentioned Case 1. In addition to the results of Example 1 and Example 2, each figure shows the transitions when the above-mentioned complete dynamics model (Equation 2, Equation 3) is applied as Example 1' and Example 2' for confirmation. Note that the part where the graphs of Example 1 and Example 2 are interrupted (end) corresponds to the arrival time at the target position. Example 1' and Example 2' can evaluate the transitions after reaching the target position. As shown in each figure, Example 2 suppresses the load swing at the target position and the subsequent load swing lower than Example 1. Also, Example 1 showed a result of extremely high agreement with the complete dynamics model (Example 1'). However, in both Examples 1 and 2, it is possible to suppress the load sway at the target position to a predetermined threshold angle or less, and it is also possible to make the suspended load LM reach the target position in the optimal shortest time.

[0097] 21, 22, 23, and 24 are graphs showing the time transitions of the radial sway angle θ1, the radial sway angular velocity θ'1, the swing direction sway angle θ2, and the swing direction sway angular velocity θ'2 in the above-mentioned Case 2. In Case 2 as well, the load swing at the target position and the subsequent load swing are suppressed lower in Example 2 than in Example 1. Moreover, Example 1 also showed a result with extremely high agreement with the complete dynamics model (Example 1'). Moreover, in both Examples 1 and 2, it is possible to suppress the load swing at the target position to a predetermined threshold angle or less, and it is possible to make the suspended load LM reach the target position in the optimal minimum time.

[0098] The crane 10 according to one embodiment of the present invention has been described above. With this configuration, it is possible to efficiently move the load LM to the target position while suppressing the swing of the load LM at the target position or during a swing operation, or both. However, the present invention is not limited to these embodiments. The present invention can take on modified embodiments such as those described below.

[0099] (1) The structure of the crane 10 is not limited to that shown in Fig. 1, and may be a crane having another structure. The crane 10 may have a jib connected to the tip of the boom 16, or may be a tower crane. Also, the crane 10 may have a gantry instead of the mast 20.

[0100] (2) The equation of motion of the load LM used in the calculation performed by the target speed calculation unit 702 is not limited to the one used in the previous embodiment. Other equations of motion of the load LM in each of the slewing direction and the radial direction, including the length of the boom 16, the length of the main hoisting rope 50, and the hoisting angle of the boom 16, may be adopted. In this case, in addition to formula I, formula II, or formula III, IV, the coefficients of the polynomial function for the slewing angle may be determined using the above-mentioned complete dynamics model based on the well-known Newton's equation of motion or Lagrange's equation of motion, or an equation of motion obtained by eliminating any infinitesimal terms from the complete dynamics model.

[0101] (3) In the above embodiment, the conditions for the radial direction swing angle θ1 and the swing direction swing angle θ2 are set in the formula 11 both at the target position and during the turning movement, but the present invention is not limited to this. The swing angle conditions may be set only at the target position or only during the turning movement. [Explanation of symbols]

[0102] 10. Crane 12 Rotating body (upper body) 13 Counterweight 14 Running body (lower body) 15 Cab 16 Boom (elevating body) 20 Mast 24 Boom guy lines 30 Boom raising winch 34 Main winch 38 Boom hoisting rope 50 Main hoisting rope (suspension rope) 57 Main Hook 70 Control section 701 Drive control unit 702 Target speed calculation section (target speed setting section) 703 Command signal generation section 704 Storage section 71 Swivel drive unit 72 Boom drive unit 73 Winch drive unit 74 Swivel control unit 75 Boom control unit 76 Winch operation unit 81 Input unit (movement information receiving unit) 82 Turning angle detector 83 Elevation angle detector 84 Rope length detector (rope length information acquisition unit) 85 Boom length acquisition unit (elevation body length information acquisition unit) 86 Suspended load detection unit 87 Display section LM hanging load θ1 Radial runout angle θ2 Swing Angle in Rotational Direction θ3 relief angle θ4 turning angle

Claims

1. A lower body and an upper body supported on the lower body so as to be rotatable about a rotation center axis extending in the vertical direction; A waving body including a waving body base end supported on the upper body so as to be rotatable in a waving direction around a horizontal rotation center axis and a waving body tip end opposite to the waving body base end; A lifting rope suspended from the tip of the elevation body and connected to a lifting load; a rotation drive unit that receives a predetermined speed command signal and is capable of rotating the upper body around the rotation central axis at a speed corresponding to the speed command signal; an undulating body length information acquisition unit that acquires undulating body length information, which is information corresponding to the length of the undulating body in a longitudinal direction of the undulating body, which is a direction connecting the base end of the undulating body and the tip end of the undulating body; A rotation angle detection unit that detects a rotation angle of the upper body about the rotation central axis; an elevation angle detection unit for detecting an elevation angle of the undulating body around the central axis of rotation; A rope length information acquisition unit that acquires rope length information corresponding to the length of the suspension rope between the tip end of the hoisting body and the suspension load; a movement information receiving unit that receives movement information including a target rotation angle for moving the load around the rotation central axis by a rotation operation of the upper body from an initial state in which the load is lifted by the lifting rope to a predetermined target position; a target speed setting unit which determines coefficients of the monomials based on an equation of motion of the load for each of the turning direction and the radial direction, the equation including at least the length of the hoisting body, the length of the load rope, and the hoisting angle, and a polynomial function for the turning angle of the upper body, the elapsed time of the turning operation being a variable, the polynomial function being composed of a plurality of monomials each including different orders of the elapsed time, so that the radial swing angle and the swing direction swing angle at least at the target position and during the turning operation are smaller than a predetermined threshold angle and the time taken for the load to reach the target position is minimized, and sets a target speed according to the elapsed time of the upper body until the target position is reached; a command signal generating unit that generates and outputs the speed command signal corresponding to the target speed set by the target speed setting unit; A crane equipped with

2. The crane according to claim 1 , wherein the command signal generating unit inputs the generated speed command signal to the slewing drive unit.

3. The crane according to claim 1 or 2, wherein the target speed setting unit determines coefficients of the plurality of monomials such that the radial sway angle and the turning direction sway angle at the target position are smaller than predetermined threshold angles.

4. 4. The crane according to claim 1, wherein the target speed setting unit further determines coefficients of the plurality of monomials so that the rotation speed of the upper body is zero when the load reaches the target position, and a radial sway angular velocity and a rotation direction sway angular velocity, which are time changes of the radial sway angle and the rotation direction sway angle, respectively, are equal to or less than a predetermined threshold angular velocity at the target position.

5. The crane according to any one of claims 1 to 4, wherein the target speed setting unit further determines coefficients of the plurality of monomials so that, during the turning operation, the moving speed of the upper body is equal to or less than a preset maximum speed, the radial sway angle and the turning direction sway angle are equal to or less than a predetermined maximum angle during movement, and the radial sway angular velocity and the turning direction sway angular velocity are equal to or less than a predetermined maximum angular velocity during movement.

6. The crane according to claim 1 , wherein the target speed setting unit sets the target speed based on the following equations I and II as equations of motion of the suspended load. I'' １ =2×θ' ２ ×θ' ４ +θ ２ ×θ'' ４ +θ １ ×θ' ４ ２ + (L / L)×θ' ４ ２ ×synth ３ -(' / ,)×θ １ ・・・(formula I) I'' ２ =-(L / l)×θ'' ４ ×synth ３ -2×θ' １ ×θ' ４ -θ １ ×θ'' ４ +θ ２ ×θ' ４ ２ -(' / ,)θ ２ ・・・ (formula II) (However, θ １ : Radial deflection angle of the suspended load, θ ２ : Swing angle of the suspended load in the rotation direction, θ' １ : Radial deflection angular velocity of the suspended load, θ' ２ : angular velocity of the load in the rotational direction, θ'' １ : Radial deflection angular acceleration of the suspended load, θ'' ２ : Rotational sway angular acceleration of the suspended load, θ ３ θ': the angle of elevation of the undulating body relative to the vertical direction ４ : the rotation angular velocity of the upper body, θ″ ４ : angular acceleration of the upper body, g: gravitational acceleration, L: length of the hoisting body, l: length of the hoisting rope from the tip of the hoisting body to the hoisting load)

7. The crane according to claim 1 , wherein the target speed setting unit sets the target speed based on the following equations III and IV as equations of motion of the suspended load. θ’’ １ = 2 × θ’ ２ × θ’ ４ + (L / l) × θ’ ４ ２ × sinθ ３ - (g / l) × θ １ ・・・(Equation III) θ’’ ２ = -(L / l) × θ’’ ４ × sinθ ３ - (g / l)θ ２ ・・・(Equation IV) (However, θ １ : Radial deflection angle of the suspended load, θ ２ : Swing angle of the suspended load in the rotation direction, θ' ２ : angular velocity of the load in the rotational direction, θ'' １ : Radial deflection angular acceleration of the suspended load, θ'' ２ : Rotational sway angular acceleration of the suspended load, θ ３ θ': the angle of elevation of the undulating body relative to the vertical direction ４ : the rotation angular velocity of the upper body, θ″ ４ : angular acceleration of the upper body, g: gravitational acceleration, L: length of the hoisting body, l: length of the hoisting rope from the tip of the hoisting body to the hoisting load)

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