JP2022190556A - crane - Google Patents

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

The present invention relates to a crane capable of moving suspended loads.

Conventionally, a mobile crane includes a lower traveling body, an upper revolving body supported by the lower traveling body so as to be able to turn around a central axis of revolving that extends in the vertical direction, and a hoisting body such as a boom or a jib. things are known. The hoisting body is attached to the front portion of the upper revolving body so as to be rotatable in the hoisting direction about a horizontal central axis of rotation. Moreover, a hook is attached to the load rope suspended from the tip of the undulating body, and the load is hoisted by connecting the load to the hook. When the upper revolving structure rotates in a state in which the suspended load is hoisted in this manner, the suspended load can be moved in the rotating direction.

Patent Literature 1 discloses a crane control method capable of suppressing swinging of a load when automatically transporting the load along a preset transport route using the crane. In the control method, the transport route is set by point cloud data consisting of a plurality of nodes (points). Then, the control device sets the target transportation time for each section by allocating the transportation required time desired by the user from the start point to the end point to the section distance between adjacent nodes. Further, the control device sets the target conveying speed for each section according to the set target conveying time. Since the target conveying speed becomes discontinuous at the boundary between the sections and load swing may occur, the control device applies a target value filter to the acceleration section and deceleration section of the target conveying speed that change stepwise like this. . The target value filter is a high-order low-pass filter based on inverse dynamics, and converts the target conveying speed, which changes stepwise as described above, into a non-step-like target conveying speed, thereby suppressing the swing of the load. Reduce.

Japanese Patent Application Laid-Open No. 2020-158278

With the technique described in Patent Literature 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 technique, the target transport time for each section is set based on the required transport time desired by the user, so the target transport speed for each section is constrained by the required transport time. For this reason, when the desired time required for transportation is relatively short, the step-shaped target transportation speed can be changed by a high-order low-pass filter based on inverse dynamics to a non-step-shaped target transportation that does not cause load swing. There is a problem that it is difficult to convert to speed, and it becomes difficult to suppress load swing at the target position.

The present invention has been made in view of the above problems, and an object of the present invention is to efficiently move the suspended load to the target position while suppressing swinging of the suspended load at least one of a target position and during a swing operation. To provide a crane that can be moved to

Provided by the present invention is a crane. The crane includes a lower main body, an upper main body, a hoisting body, a load rope, a slewing drive section, a slewing body length information acquisition section, a slewing angle detection section, a rope length information acquisition section, and movement information. It includes a 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 about a center axis of rotation extending in the vertical direction. The undulating body includes an undulating body base end portion supported by the upper body so as to be rotatable in the undulating direction around a horizontal rotation center axis, and an undulating body distal end portion opposite to the undulating body base end portion. . A suspended load rope is suspended from the tip of the undulating body and connected to a suspended load. The turning driving section can receive a predetermined speed command signal and turn the upper body around the turning 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 longitudinal direction of the undulating body, which is the direction connecting the base end of the undulating body and the tip end of the undulating body. . The turning angle detection unit detects a turning angle of the upper body about the turning central axis. The hoisting angle detection unit detects the hoisting angle of the hoisting body about the rotation center axis. The rope length information acquisition unit acquires rope length information, which is information corresponding to the length of the load rope between the tip of the undulating body and the load. The movement information receiving unit moves the suspended load from an initial state in which the suspended load is lifted by the suspended load rope to a predetermined target position about the rotation center axis by rotating the upper body. receive the movement information including the target turning angle. The angle of the hoisting body with respect to the vertical direction of the load rope when viewed along the turning direction of the upper body is the radial swing angle, and the hoisting body is viewed along the radial direction of the turning movement of the upper body. If the angle of the load rope with respect to the vertical direction in the above case is defined as the turning direction swing angle, the target speed setting unit sets the turning direction including at least the length of the hoisting body, the length of the lifting load rope, and the hoisting angle, and the A plurality of equations of motion of the suspended load in each of the radial directions, and a polynomial function of the swing angle of the upper body with the elapsed time of the swing motion as a variable, each including a different degree of the elapsed time. and a polynomial function composed of mononomials, wherein the radial deflection angle and the swinging direction deflection angle at least one of the target position and during the swinging motion are smaller than a predetermined threshold angle and the target of the suspended load. Coefficients of the plurality of monomials are each determined so as to minimize time to reach a position, and a target velocity is set according to the elapsed time of the upper body until reaching the target position. The command signal generator generates and outputs the speed command signal corresponding to the target speed set by the target speed setting unit.

According to this configuration, the target speed setting unit, based on the equation of motion of the suspended load and the polynomial function, determines that the swing angle of the suspended load in two directions during the target position or turning movement is smaller than the threshold angle and that the load reaches the target position. A target velocity of the upper body can be set such that the time is minimized. Therefore, the target speed of the upper body is not affected by the required movement time unlike the case where the required movement time is set in advance by the operator. The suspended load can be moved in the shortest possible moving time. Therefore, it is possible to efficiently move the suspended load to the target position while suppressing swinging of the suspended load at the target position or during turning movement.

In the above configuration, the command signal generation section may input the generated speed command signal to the turning drive section.

According to this configuration, based on the speed command signal generated by the command signal generator, the upper body can be automatically turned so as to move the suspended load to the target position while suppressing the swinging of the load at the target position. .

In the above configuration, the target speed setting unit may determine coefficients of the plurality of monomials so that the radial deflection angle and the turning direction deflection angle at the target position are smaller than a predetermined threshold angle. good.

In the above configuration, the target speed setting unit further sets the turning speed of the upper body to zero when the suspended load reaches the target position, and sets the radial deflection angle and the turning direction deflection angle to The coefficients of the plurality of monomials may be respectively determined so that the radial direction swing angular velocity and the turning direction swing angular velocity, which are temporal changes in , are equal to or less than a predetermined threshold angular velocity at the target position.

In the above configuration, the target speed setting unit further sets the movement speed of the upper body to a preset maximum speed or less during the turning motion, and sets the radial direction deflection angle and the turning direction deflection angle to predetermined values. , and the coefficients of the plurality of monomials may be determined so that the radial swing angular velocity and the turning direction swing angular velocity are equal to or lower than a predetermined maximum moving angular velocity.

Said structure WHEREIN: The said target speed setting part may set the said target speed based on the following Formulas I and Formula II as a motion equation of the said suspended load.
θ'' ₁ = 2 × θ' ₂ × θ' ₄ + θ ₂ × θ'' ₄ + θ ₁ × θ' ₄ ² + (L/l) × θ' ₄ ² × sin θ ₃ - (g/l) × θ ₁ (Formula I)
θ″ ₂ =−(L/l)×θ″ ₄ ×sin θ ₃ −2×θ′ ₁ ×θ′ ₄ −θ ₁ ×θ′ ₄ +θ ₂ ×θ′ ₄ ² −(g/l) θ ₂ (Formula II)
(However, θ ₁ : radial swing angle of suspended load, θ ₂ : swing angle of suspended load in turning direction, θ′ ₁ : radial swing angular velocity of suspended load, θ′ ₂ : swing angular speed of suspended load in swing direction, θ '' ₁ : Radial direction swing angular acceleration of the suspended load, _θ''2 : Rotating direction swing angular acceleration of the suspended load, θ3: Luffing angle of the undulating body with respect to the vertical direction, _θ′4 : _Rotating angular velocity of the upper body , θ″ ₄ : turning angular acceleration of the upper body, g: gravitational acceleration, L: length of the undulating body, l: length of the lifting rope from the tip of the undulating body to the suspended load)

Said structure WHEREIN: The said target speed setting part may set the said target speed based on the following formulas III and Formula IV as a motion equation of the said suspended load.
θ″ ₁ =2×θ′ ₂ ×θ′ ₄ +(L/l)×θ′ ₄ ² ×sin θ ₃ −(g/l)×θ ₁ (formula III)
θ″ ₂ =−(L/l)×θ″ ₄ ×sin θ ₃ −(g/l) θ ₂ (formula IV)
(However, θ ₁ : radial swing angle of suspended load, θ ₂ : swing angle of suspended load in turning direction, θ′ ₂ : swing angular velocity of suspended load in swing direction, θ″ ₁ : radial swing angular acceleration of suspended load , θ″ ₂ : swaying angular acceleration of the suspended load in the turning direction, θ ₃ : undulation angle of the undulating body with respect to the vertical direction, θ′ ₄ : turning angular velocity of the upper body, θ″ ₄ : turning angle of the upper body acceleration, g: gravitational acceleration, L: length of the undulating body, l: length of the rope from the tip of the undulating body to the suspended load)

ADVANTAGE OF THE INVENTION According to this invention, the crane which can move a suspended load efficiently to the said target position is provided, suppressing the swinging of a suspended load in at least one of a target position and swing motion.

1 is a side view of a crane according to one embodiment of the invention; FIG. FIG. 4 is a schematic perspective view for explaining swing control of a crane according to one embodiment of the present invention; 1 is a block diagram of a crane according to one embodiment of the present invention; FIG. 4 is a flow chart of swing control of a crane according to one embodiment of the present invention. FIG. 11 is an example of a pivoting velocity profile of the upper body; FIG. 5 is a graph showing temporal transition of radial deflection angle in the example of the present invention. FIG. 5 is a graph showing the time transition of the swing angle in the turning direction in the embodiment of the present invention; FIG. It is a graph which shows the time transition of the turning angle in the Example of this invention. It is a graph which shows time transition of turning angular velocity in the Example of this invention. 5 is a graph showing temporal transition of radial deflection angle in the example of the present invention. FIG. 5 is a graph showing the time transition of the swing angle in the turning direction in the embodiment of the present invention; FIG. It is a graph which shows the time transition of turning torque in the Example of this invention. It is a graph which shows the time transition of the turning angle in the Example of this invention. It is a graph which shows time transition of turning angular velocity in the Example of this invention. It is a graph which shows the time transition of the turning angle in the Example of this invention. It is a graph which shows time transition of turning angular velocity in the Example of this invention. 5 is a graph showing temporal transition of radial deflection angle in the example of the present invention. 4 is a graph showing temporal transition of radial deflection angular velocity in the example of the present invention. FIG. 5 is a graph showing the time transition of the swing angle in the turning direction in the embodiment of the present invention; FIG. FIG. 5 is a graph showing the time transition of the turning direction swing angular velocity in the example of the present invention. FIG. 5 is a graph showing temporal transition of radial deflection angle in the example of the present invention. 4 is a graph showing temporal transition of radial deflection angular velocity in the example of the present invention. FIG. 5 is a graph showing the time transition of the swing angle in the turning direction in the embodiment of the present invention; FIG. FIG. 5 is a graph showing the time transition of the turning direction swing angular velocity in the example of the present invention. FIG.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a crane 10 according to this embodiment. Note that FIG. 1 shows "up", "down", "front", and "rear" directions, but these directions are used for the structure of the crane 10 according to the present embodiment and for swing control described later. It is shown for the convenience of explanation, and does not limit the moving direction, the mode of use, etc. of the crane according to the present invention.

The crane 10 includes a traveling body 14 (lower body), a revolving body 12 (upper body) supported by the traveling body 14 so as to be able to turn about a turning center axis extending in the vertical direction, a boom 16 (elastic body), and a mast. 20 and. A counterweight 13 for adjusting the balance of the crane 10 is loaded on the rear portion of the revolving body 12 . A cab 15 is provided at the front end of the revolving body 12 . Cab 15 corresponds to the driver's seat of crane 10 .

The boom 16 shown in FIG. 1 is of a so-called lattice type, comprising a lower boom 16A (bottom end of the hoisting body), one or more (three in the figure) intermediate booms 16B, 16C, and 16D, and an upper boom 16E. (leading edge portion of the undulating body opposite to the basal end portion of the undulating body). Specifically, the lower boom 16A is supported on the front portion of the revolving body 12 so as to be rotatable about a horizontal rotation center axis (first rotation center axis) in the undulating direction. The intermediate booms 16B, 16C, and 16D are detachably added to the tip side of the lower boom 16A in that order. The upper boom 16E is detachably added to the tip side of the intermediate boom 16D. The lower boom 16A is rotatably supported by the revolving body 12 at a boom foot pin 16S provided at its lower end.

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

However, the specific structure of the boom is not limited in the present invention. For example, the boom may have no intermediate members, or may have a different number of intermediate members. Additionally, the boom may be constructed from a single piece.

The mast 20 has a base end and a rotating end, and the base end is rotatably connected to the revolving body 12 . The pivot axis of the mast 20 is parallel to the pivot axis of the boom 16 and positioned just behind the pivot axis of the boom 16 . That is, the mast 20 is rotatable in the same direction as the boom 16 is raised and lowered.

Further, the crane 10 includes a pair of left and right boom backstops 23 and a pair of left and right boom guy lines 24 .

A pair of left and right boom backstops 23 are provided on both left and right sides of the lower boom 16A of the boom 16 . These boom backstops 23 come into contact with the central portion of the revolving body 12 in the longitudinal direction when the boom 16 reaches the upright posture shown in FIG. This abutment prevents the boom 16 from being blown backward by strong winds or the like.

A pair of left and right boom guylines 24 connect the pivot 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 .

Moreover, the crane 10 further includes various winches. Specifically, the crane 10 includes a boom hoisting winch 30 for hoisting the boom 16, and a main hoisting winch 34 and an auxiliary hoisting winch 36 for hoisting and lowering a suspended load. The crane 10 also includes a boom hoisting rope 38 , a main hoisting rope 50 (suspended load rope) suspended from the tip of the boom 16 and connected to a hoisted load, and an auxiliary hoisting rope 60 . In the crane 10 according to the present embodiment, a main hoisting winch 34 and an auxiliary hoisting winch 36 are installed near the base end of the boom 16 . Also, a boom hoisting winch 30 is installed on the revolving body 12 . The positions of these winches 30, 32, 34, 36 are not limited to the above.

The boom hoisting winch 30 winds up and lets out a boom hoisting rope 38 . The boom hoisting rope 38 is routed so that the mast 20 is rotated by this winding and unwinding. Specifically, sheave blocks 40 and 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 revolving body 12, respectively. A boom hoisting rope 38 is stretched between sheave blocks 40 and 42 . Therefore, when the boom hoisting winch 30 winds up or feeds out the boom hoisting rope 38, the distance between the two sheave blocks 40 and 42 changes, thereby raising and lowering the mast 20 and the boom 16 interlocked therewith. direction.

The main hoisting winch 34 hoists and lowers the suspended load by the main hoisting rope 50 . A main hoisting rope 50 (suspended load rope) hangs down from the tip of the boom 16 and is connected to a suspended load. A main hoisting guide sheave 54 is arranged at the tip of the boom 16, and a main hoisting sheave block having a plurality of main hoisting point sheaves 56 arranged in the width direction is provided adjacent to the main hoisting guide sheave 54. is provided. A main hoisting rope 50 pulled out from a main hoisting winch 34 is sequentially hooked to an idler sheave 34S and a main hoisting guide sheave 54, and furthermore, a main hoisting point sheave 56 of the sheave block and a main hook 57 for hoisting cargo. and the sheave 58 of the sheave block provided in the . Therefore, when the main hoisting winch 34 winds or pays out the main hoisting rope 50, the distance between the sheaves 56 and 58 changes, and the main hoisting rope 50 suspended from the tip of the boom 16 is connected to the main hoisting rope 50. The hook 57 is hoisted and lowered. As a result, the load can be hoisted and lowered.

Similarly, the auxiliary hoisting winch 36 hoists and lowers the suspended load with the auxiliary hoisting rope 60 . For the auxiliary winding, an auxiliary winding guide sheave 64 is rotatably provided coaxially with the main winding guide sheave 54, and an auxiliary winding point sheave (not shown) is rotatable at a position adjacent to the auxiliary winding guide sheave 64. is provided in The auxiliary hoisting rope 60 pulled out from the auxiliary hoisting winch 36 is sequentially hung on the idler sheave 36S and the auxiliary hoisting guide sheave 64, and suspended from the auxiliary hoisting point sheave. Therefore, when the auxiliary hoisting winch 36 winds or unwinds the auxiliary hoisting rope 60, the auxiliary hook (not shown) connected to the end of the auxiliary hoisting rope 60 is hoisted or lowered.

FIG. 2 is a schematic perspective view for explaining swing control of the crane 10 according to this embodiment. FIG. 3 is a block diagram of the crane 10 according to this embodiment.

In FIG. 2 , for the sake of explanation, the base end of the boom 16 is shown as being positioned on the center axis of rotation of the rotating body 12 . In FIG. 2, L is the length of the boom 16, l (small letter L) is the length from the tip of the boom 16 to the suspended load LM of the main hoisting rope 50 suspended. Angles θ ₁ and θ ₂ indicate swing angles of the suspended load LM. Specifically, the angle θ ₁ is
The angle of the main hoist rope 50 with respect to the vertical direction when the boom 16 is viewed along the turning direction of the revolving body 12, and is referred to as the radial deflection angle θ ₁ (the deflection angle on the normal plane). On the other hand, the angle θ ₂ is the angle with respect to the vertical direction of the main hoist rope 50 when the boom 16 is viewed along the radial direction of the swing motion of the swing body 12, and is referred to as swing direction deflection angle θ ₂ (in the tangential plane deflection angle). Note that depending on the swinging motion of the suspended load LM, the radial swing angle θ ₁ and the turning direction swing angle θ ₂ may take not only positive values but also negative values.

The angle θ4 is the turning angle of the revolving body ₁₂ about the central axis of rotation _, and the angle θ3 is the hoisting angle of the boom 16 about the central axis of rotation. . In the coordinate system of FIG. 2, the origin is the base end of the boom 16, the X-axis is a predetermined horizontal direction (for example, the forward direction of the traveling body 14), the Y-axis is a horizontal direction orthogonal to the X-axis, A direction (vertical direction) perpendicular to each of the X-axis and the Y-axis is defined as the Z-axis.

In this embodiment, as shown in FIG. 2, when the suspended load LM suspended from the tip of the boom 16 (elastic body) is turned by the turning motion of the turning body 12 ₍ change in turning angle θ4), To move a suspended load LM to a target position as quickly as possible while suppressing swinging of the suspended load LM at the target position.

Referring to FIG. 3 , crane 10 includes control unit 70 , swing drive unit 71 , boom drive unit 72 , winch drive unit 73 , swing operation unit 74 , boom operation unit 75 , winch operation unit 76 . , an input unit 81 (movement information reception unit), a turning angle detection unit 82, a hoisting angle detection unit 83, a rope length detection unit 84 (rope length information acquisition unit), and a boom length acquisition unit 85 ( It further includes an undulating body length information acquisition section, a suspended load detection section 86 and a display section 87 .

The turning drive unit 71 can receive a predetermined speed command signal and turn the turning body 12 around the turning center axis at a speed corresponding to the speed command signal. Specifically, the turning driving section 71 generates driving force capable of turning the turning body 12 around the turning center axis in a first turning direction and a second turning direction opposite to the first turning direction. do. The swing drive unit 71 includes a hydraulic swing motor that swings the swing body 12 by being supplied with hydraulic oil.

The boom driving section 72 is capable of generating driving force for rotating the boom hoisting winch 30 and rotating the boom 16 around the rotation center axis. The boom drive unit 72 includes a hydraulic motor that rotates the boom hoisting winch 30 by being supplied with hydraulic oil.

The winch drive unit 73 generates a driving force for rotating the main hoisting winch 34, and winds and lets out the main hoisting rope 50 by the main hoisting winch 34, thereby moving the suspended load LM relative to the ground. can be raised and lowered. The winch drive unit 73 includes a hydraulic suspended load motor that rotates the main hoist winch 34 by being supplied with hydraulic oil. A winch driving section (not shown) for rotating the auxiliary hoisting winch 36 is also provided.

The swing operation unit 74 , the boom operation unit 75 and the winch operation unit 76 are arranged inside the cab 15 and receive operations for driving each member of the crane 10 by the operator.

The turning operation unit 74 receives an operation for driving the turning body 12 to turn by the turning driving unit 71 . The turning operation unit 74 can be switched between a turning position for turning the turning body 12 in the first turning direction and the second turning direction, respectively, and a neutral position for stopping the turning of the turning body 12. It is

The boom operating section 75 receives an operation for raising and lowering the boom 16 by the boom driving section 72 . The boom operating section 75 is switchable between a hoisting position for hoisting the boom 16 and a neutral position for stopping the hoisting of the boom 16 . At the hoisting position, it is possible to operate the boom 16 in the erecting direction and in the laying down direction.

The winch operation portion 76 receives an operation for raising and lowering the suspended load LM by the winch drive portion 73 . The winch operation portion 76 is switchable between a lifting position for lifting the suspended load LM and a neutral position for stopping the lifting of the suspended load LM. At the lifting position, it is possible to operate in the upward direction for raising the suspended load LM and the downward direction for lowering the suspended load LM.

The input unit 81 is arranged inside the cab 15 and receives input of information on control of the crane 10 by the operator. As an example, the input unit 81 includes a touch panel type input device, various switches, buttons, and the like. The input unit 81 is for moving the suspended load LM from the initial state in which the suspended load LM is lifted by the main hoisting rope 50 to a predetermined target position about the rotation center axis by the rotating motion of the rotating body 12 . The movement information including the target turning angle θ _f4 is accepted.

The turning angle detection unit 82 detects and outputs a turning angle θ4 of the turning body ₁₂ (boom 16) about the center axis of turning. The turning angle detection unit 82 includes a gyro sensor (IMU sensor) and a calculation unit (not shown). The turning angle detection unit 82 measures the angular velocity about the turning center axis of the turning body 12 with the gyro sensor, and the calculating unit converts the measured angular velocity into an angle by integrating once with respect to time. , the angle is output as the turning angle _θ4 . It should be noted that the structure of the turning angle detection unit 82 is not limited to the above, and a known goniometer, encoder, or the like may be used.

The hoisting angle detection unit 83 detects and outputs the hoisting angle _θ3 of the boom 16 about the rotation center axis. The hoisting angle detection unit 83 is composed of an inclination sensor and detects the relative angle of the boom 16 with respect to the vertical direction. Note that the undulation angle detection unit 83 may detect a relative angle with respect to other objects. For example, the hoisting angle detection unit 83 detects the ground angle of the boom 16 (angle relative to the horizontal direction) _, and subtracts the ground angle from 90 degrees to calculate and output the hoisting angle θ3. good. Also, the hoisting angle detector 83 may be a known goniometer or the like.

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 suspended load LM. In this embodiment, the distance between the main hoisting 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 that can detect the amount of rotation of the main hoisting winch 34, and a winding layer detection unit that detects the number of winding layers of the main hoisting rope 50 on the outer peripheral surface of the main hoisting winch 34. including the part. The rope length detection unit 84 is estimated from the winch diameter of the main hoisting winch 34, the amount of winch rotation detected by the rotation amount detection unit, and the winding layer of the main hoisting rope 50 detected by the winding layer detection unit. The distance is calculated from the amount of the main hoisting rope 50 let out from the main hoisting winch 34 and the number of hooks of the main hoisting rope 50 between the main hoisting point sheave 56 and the sheave block of the sheave 58. Output.

Note that the method of detecting the length l of the main hoisting rope 50 is not limited to the above mode. For example, the rope length may be detected by sandwiching the wire between sheaves (not shown) and measuring the rotation of the sheaves with an encoder, or the area below the tip of the boom 16 (boom top) by three-dimensional LIDAR. may be measured in real time to detect the suspended load, and the length of the rope may be determined by measuring the distance from the boom top to the suspended load. Alternatively, the length of the rope may be calculated by measuring the distance to the suspended load using a known stereo camera or sound waves. In this case, the reference point for distance measurement may be any portion of the boom such as the boom top, the main body of the crane, the ground other than the crane, or the like. Furthermore, the length of the rope may be calculated by attaching a position-measurable sensor such as GPS to the suspended load.

The boom length acquisition unit 85 acquires information on the length (L) of the boom 16 used in the swing control of the swing body 12 executed by the control unit 70 . That is, the boom length acquisition unit 85 measures the length of the boom 16 in the longitudinal direction of the boom (longitudinal direction of the hoisting body), which is the direction connecting the base end (base end of the hoisting body) and the tip (tip of the hoisting body) of the boom 16 . Acquires and outputs information corresponding to the length of the (relief body length information). 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 an input unit that receives information on the length of the boom 16 from the operator. Therefore, 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. Furthermore, when a plurality of booms 16 having different lengths are selectively attached to the revolving body 12, the boom length acquisition unit 85 obtains information on the length of the booms 16 from the RFID or the like attached to each boom 16. may be a receiving unit that receives the

The suspended load detection unit 86 acquires and outputs information on the weight of the suspended load LM connected to the main hook 57 (suspended load amount information). In the present embodiment, the suspended load detection unit 86 includes a load detector (load cell) (not shown) connected to the main hoisting rope 50, and determines whether the suspended load LM is detected based on changes in strain in the tension of the main hoisting rope 50. Detect weight. In another embodiment, 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.

The display unit 87 is a display arranged in the cab 15 and displays various information for notifying the operator.

The control unit 70 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) for storing control programs, a RAM (Random Access Memory) used as a work area for the CPU, and the like. The control unit 70 includes 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 executing the control program stored in the ROM by the CPU. function.

Drive control unit 701 sends command signals corresponding to the operation direction and amount of operation received by turning operation unit 74 , boom operation unit 75 and winch operation unit 76 to turning drive unit 71 , boom drive unit 72 and winch drive unit 73 . Each drive unit is driven by each input.

The target speed calculator 702 sets the target speed of the revolving superstructure 12 until the suspended load LM reaches the target position when the automatic swing control is executed. The automatic turning control is a control for automatically moving the suspended load LM from a predetermined initial position to a target position in the turning direction.

A command signal generator 703 generates and outputs a speed command signal corresponding to the target speed set by the target speed calculator 702 . The speed command signal output by the command signal generation section 703 is input to the turning drive section 71 . As a result, the revolving motion of the revolving body 12 is automatically controlled. In another embodiment, the speed command signal may be input to the display unit 87, and the operator may operate the turning operation unit 74 according to the magnitude and direction of the speed command signal (turning assist).

The storage unit 704 stores parameters, thresholds, and the like that are referred to during various controls executed in the crane 10 .

<Turn control flow>
FIG. 4 is a flowchart of swing control of the crane 10 according to this embodiment. When the control unit 70 automatically controls the turning motion, the control unit 70 first determines 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 determines whether movement information is stored in the storage unit 704 (step S2). As described above, the movement information includes the target turning angle θ _f4 to the target position for moving the suspended load LM, and is stored in the storage section 704 by being input through the input section 81 by the operator.

If there is movement information in step S2 (YES in step S2), turning angle detection unit 82, hoisting angle detection unit 83, and rope length detection unit 84 detect turning angle θ ₄ , hoisting angle θ ₃ , and main hoisting rope, respectively. A length l of 50 is detected (step S3). The detected information is stored in the storage 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.

When each piece of information is detected in step S<b>3 , the boom length obtaining section 85 obtains the length (L) of the boom 16 . As described above, the length of boom 16 may be stored in advance in storage unit 704 or may be input through input unit 81 or the like.

Next, the target speed calculator 702 calculates a profile (transition) of the swing speed (swing angular speed θ′ ₄ ) of the swing structure 12 from the initial position to the target position of the suspended load LM (step S5). That is, in this embodiment, in order to suppress the swing of the suspended load LM, the angular velocity _θ′4 of the swing body ₁₂ is controlled to change according to the swing angle θ4. In the following description, the derivative of θ (angular velocity) may be expressed as θ′, and the second derivative of θ (angular acceleration) may be expressed as θ″. The transition of the calculated turning angular velocity _θ'4 is displayed on the display unit 87 and can be confirmed by the operator.

When the speed profile (transition of the angular velocity _θ'4 ) is determined in step S5, the target speed calculator 702 calculates the estimated swing amount of the suspended load LM at the target position in step S6. At this time, the swing angle θ ₁ in the radial direction and the swing angle θ ₂ in the turning direction of the suspended load LM are calculated from the equation of motion described above, and the results are displayed on the display unit 87 .

Next, the command signal generator 703 generates a speed command signal corresponding to the calculated angular velocity _θ′4 (step S 7 ) and inputs it to the turning drive unit 71 . As a result, the revolving drive section 71 revolves the revolving body 12, and the revolving motion of the revolving body 12 is automatically controlled (step S8).

<Calculation of turning speed>
Next, the calculation of the turning speed (angular speed θ′ ₄ ) executed in step S5 will be described in detail.

When the revolving structure 12 turns toward the target position from the state in which the suspended load LM is lifted by the boom 16 at the initial position, the suspended load LM connected to the main hoisting rope 50 has a two-dimensional shape in the radial direction and the turning direction. significant load swing occurs. The boom 16 can move vertically by undulating itself in addition to horizontal movement by turning together with the revolving body 12 . Therefore, in order to suppress the two-dimensional load swing as described above, it is also possible to adjust the hoisting angle θ ₃ of the boom 16 during movement in addition to the swing speed (angular velocity θ′ ₄ ) of the swing body 12 . Conceivable. However, since such vertical movement of the suspended load LM works against the force of gravity, more complicated swinging of the load is likely to occur. become difficult.

Therefore, in the present embodiment, the control unit 70 determines the temporally optimum trajectory only by turning the turning body 12, that is, moving the boom 16 in the horizontal direction, and suppresses the swinging of the load at the target position. _In other words, the hoisting angle θ3 of the boom 16 is fixed during the pivoting movement. The trajectory referred to here includes not only a positional trajectory but also a temporal element, and includes the problem of which position the suspended load LM passes at each time. Furthermore, the control unit 70 suppresses continuous swinging of the suspended load LM after reaching the target position as much as possible.

Assuming that the torque applied to the swing motor (not shown) included in the swing drive unit 71 that drives the swing body 12 is τ4, the torque _τ4 can be expressed by the following equation ₁ from the Lagrangian equation of motion.

Table 1 below shows the definition of some parameters included in the above formula 1 and each formula described later.

Supplementing the parameters in Equation 1, J ₄ and I _b are the moments of inertia acting on the rotating bed 12 and boom 16 . As shown in Table 1, I _x , I _y , and I _z are moments of inertia about each coordinate axis applied to the boom 16 .

Here, from the balance of the external force applied to the suspended load LM in FIG. can be represented.

Note that g in Equations 2 and 3 is the gravitational acceleration. Equations 2 and 3 are defined as a reference (perfect) dynamics model representing the swing of the suspended load LM. On the other hand, in formulas 2 and 3, the product of the square of θ and the second derivative of θ, and the product of θ and the square of the first derivative of θ are relatively small values. can be omitted (θ includes θ ₁ and θ ₂ ). Therefore, Equations 2 and 3 can be replaced with Equations 4 and 5 below.

Equations 4 and 5 are defined as a first dynamics model representing the swing of the suspended load LM. Formulas 4 and 5 correspond to formulas I and II of the present invention. Further, by omitting the second and third terms on the right side of the above formula 4 and the second, third and fourth terms on the right side of the formula 5, the following formulas 6 and 7 can be obtained. can.

Equations 6 and 7 are defined as a second dynamics model representing the swing of the suspended load LM. Formulas 6 and 7 correspond to formulas III and IV of the present invention. Furthermore, in this embodiment, in order to simplify the dynamic movement of the boom 16 and generate the optimum time trajectory, the target speed calculator 702 calculates the swing angle θ4 of the swing structure 12 as shown in Equation ₈ below. 2, is defined by a polynomial function in which the elapsed time t of the turning motion based on the initial position (the starting point of the turning motion) is used as a variable.

As shown in Equation 8, in this embodiment, as a model that simplifies the motion of the boom 16, it is formulated using a sixth-order polynomial. The b _i (i=1-6) in Equation 8 are polynomial coefficients determined by optimization. However, since the turning angle θ ₄ =0 and the turning angular velocity θ′ ₄ =0 in the initial state when the turning motion of the turning body 12 is started, the coefficients b ₀ and b ₁ are assigned zero. Therefore, the five coefficients b ₂ , b ₃ , b ₄ , b ₅ , b ₆ are adjusted by optimization. The order of the polynomial is not limited to 6, and a lower or higher order polynomial may be used.

Here, if the time when the suspended load LM reaches the target position is T, the time (elapsed time) t during the turning motion can be expressed as t=ST. S is a vector containing discrete values in the range 0≤S≤1. As a result, Equation 8 can be expressed as Equation 9 below.

The target speed calculation unit 702 quickly moves the suspended load LM to the target position by setting the polynomial coefficients b _i (i=2 to 6) so that the arrival time T in the above equation 9 is minimized. be able to. At this time, in order to suppress the load swing of the suspended load LM, the radial direction swing angle θ ₁ and the turning direction swing angle θ ₂ defined by the above-described Equations 4 and 5 or Equations 6 and 7 must be adjusted to the target position. It is desirable that the angle is suppressed to a predetermined threshold angle or less in , and that the angle is suppressed to a predetermined maximum angle or less even during movement to the target position. Therefore, the above problem can be represented by Equations 10 and 11 below.

Equation 10 means the problem of optimizing the polynomial coefficients b _i (i=2 to 6) that minimizes the arrival time T, and Equation 11 means the conditions therefor. Referring to Equation 11 from top to bottom, the turning angle θ ₄ (T) at time T is the target turning angle θ _f4 . The turning angular velocity θ′ ₄ (T) at time T, ie, the target position, is zero. Also, the absolute value of the turning angular velocity θ′ ₄ (t) (velocity) during movement is set to be equal to or less than the maximum turning angular velocity θ′ _max4 (maximum speed) preset from the characteristics of the turning drive section 71 . Furthermore, the absolute value of the swing angle θ _i (T) (i=1, 2) at the target position is set to be equal to or less than a preset final load swing allowable angle θ _f (threshold angle). Similarly, the absolute value of the swing angular velocity θ' _i (T) (i=1, 2) at the target position is set to be equal to or less than a preset final allowable load swing angular speed θ' _f (threshold angular speed). Also, the absolute value of the swing angle θ _i (t) (i=1, 2) during movement is set to be equal to or less than a preset allowable load swing angle during movement θ _SW (maximum angle during movement). Similarly, the absolute value of the swing angular velocity θ′ _i (t) (i=1, 2) during movement is set to be equal to or less than a preset allowable swing angular velocity during movement θ′ _SW (maximum angular velocity during movement). . The above parameters are also shown in Table 1 above. Note that each angular velocity corresponds to the time change of the corresponding angle.

In the present embodiment, the target speed calculation unit 702 calculates the above problem by sequential quadratic programming as an example. It should be noted that the target speed calculation unit 702 uses the above-described formulas 4, 5, 9, 10 and 11 (second embodiment described later) or formula 6 according to the calculation accuracy and calculation time required at the work site. , Eq. 7, Eq. 9, Eq. 10 and Eq. 11 (Embodiment 1 described later) can be used to calculate the optimum solution. By this calculation, the polynomial coefficients b _i (i=2 to 6) of Equation 9 are optimized, respectively, and when the minimum arrival time T of Equation 10 is determined, the expected arrival time is displayed on the display unit 87. good too. Further, the target speed calculator 702 determines the transition of the turning angle θ4 at each time during movement from Equation ₉ , and also determines the transition of the turning angular velocity _θ′4 from the differentiation thereof. Based on this result, the command signal generator 703 can generate the speed command signal in step S7.

On the other hand, the target speed calculation unit 702 calculates the radial deflection angle θ ₁ and the turning direction deflection angle θ ₂ at the target position from the above optimization result using Equations 4 and 5 or Equations 6 and 7. can be calculated (step S6 in FIG. 4). At this time, the target speed calculation unit 702 may calculate the radial deflection angle θ1 and the turning direction deflection angle θ2 from Equations ( ₂ ) and ( ₃ ).

As described above, in the present embodiment, the target speed calculator 702 calculates the target speed (angular speed θ′ ₄ ) of the revolving superstructure 12 based on the equation of motion of the suspended load LM based on dynamics and a predetermined polynomial function. Calculate. 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 each of the turning direction and the radial direction. Further, the polynomial function is a polynomial function for the turning angle θ4 of the turning body ₁₂ with the elapsed time t of turning operation based on the initial position as a variable. The polynomial function is composed 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 that the radial deflection angle θ ₁ and the turning direction deflection angle θ ₂ at the target position are smaller than a predetermined threshold angle and that the suspended load LM reaches the target position. The target velocity (angular velocity θ′ ₄ ) is set according to the elapsed time t of the revolving structure 12 until reaching the target position by determining the coefficients of the plurality of monomials so that the arrival time T of is minimized. .

In particular, in this embodiment, the target speed calculator 702 determines that the swing angles θ ₁ and θ ₂ of the suspended load LM in two directions at the target position are predetermined threshold angles based on the equation of motion of the suspended load LM and the polynomial function. The target speed of the revolving superstructure 12 can be set such that it is smaller than , and the arrival time of the suspended load LM is minimized. Therefore, the target speed of the revolving structure 12 is not affected by the required movement time unlike the case where the required movement time is set in advance. The suspended load LM can be moved during the moving time. Therefore, it is possible to efficiently move the suspended load LM to the target position while suppressing swinging of the suspended load LM at the target position.

Further, in the present embodiment, the target speed (change in angular speed) of the revolving superstructure 12 can be optimized so that the arrival time of the suspended load LM is minimized. In this case, the conditions for optimizing this problem already include the swing constraint of the suspended load LM. Therefore, as in the conventional case, the transition of the conveying speed once set is subject to filter processing (target value filter) based on inverse dynamics, thereby correcting the above conveying speed so as to suppress the swing of the load. By comparison, it is possible to set the optimum target speed of the revolving superstructure 12 corresponding to a wide range of conditions. In addition, compared to the case where the transfer time to the target value is set in advance, the target speed of the revolving structure 12 is not restricted by the transfer time, and the load swing can be suppressed in the minimum time. It becomes possible to cause the suspended load LM to reach the target position.

Furthermore, in the present embodiment, the calculations executed by the target speed calculation unit 702 include the length of the main hoisting rope 50 (the position of the main hook 57), the hoisting angle θ3 of the boom 16, and the length of the boom 16 (turning radius). Since the equation of motion of the suspended load LM including is used, the suspended load LM can be moved to the target position in a short time while suppressing the swing of the suspended load LM with high accuracy.

Further, when the first dynamics model of the two dynamics models described above is used to optimize the turning angular velocity _θ′4 in the turning operation of the turning body 12, the suspended load LM is moved to the target position. The load can be reached in the shortest time, and the swing of the suspended load LM can be suppressed while maintaining high waveform matching with the complete dynamics model (full model).

Next, the present invention will be described in further detail based on examples. In addition, the present invention is not limited to the following examples.

<Verification of simplified dynamics model>
As described above, in order to calculate a slewing speed that satisfies a predetermined condition in slewing control of the crane 10, the target speed calculation unit 702 uses the first dynamics model (Eq. 4, Eq. 5) or the second dynamics model The model (Formula 6, Formula 7) is adopted. Since these are simplifications of the full dynamics model (equations 2 and 3), their validity is verified. FIG. 5 is an example of a basic swing speed profile (cycloidal boom speed). FIG. 6 is _a graph showing temporal transition of the radial deflection angle θ1 in the embodiment of the present invention. _FIG . 7 is a graph showing the time course of the swing angle θ2 in the turning direction in the embodiment of the present invention.

The relationship between time and turning angular velocity in FIG. 5 can be represented by the following Equation 12.

θ' _max4 in Equation 12 corresponds to the maximum angular velocity in FIG. 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 are zero. Along with such velocity profiles, conditions as shown in Table 2 below were applied to the first dynamics model (Example 2), the second dynamics model (Example 1), and the complete dynamics model (reference example), respectively. 6 and 7 show transitions of the radial deflection angle θ ₁ and the turning direction deflection angle θ ₂ calculated by the input. Note that under each condition, the velocity and acceleration are calculated with a sampling time of 10 msec.

6 and 7, the first dynamics model (formula 4, formula 5) agrees with the complete dynamics model at both radial runout angle θ ₁ and turning direction runout angle θ ₂ . became. On the other hand, compared to the first dynamics model, the second dynamics model, in which more terms are omitted, _approximated the complete dynamics model at the radial runout angle θ1, but the turning direction runout angle In the case of θ ₂ , there was a deviation from the complete dynamics model in the latter half of the time domain. Therefore, in terms of matching with the complete dynamics model, the first dynamics model gave better results.

<Constraints for load swing>
As described above, in the present invention, the slewing speed is set so that the load LM reaches the target position in the shortest time, and the load swing at the target position and during movement is within a predetermined threshold angle (load swing constraint condition). is optimized. For this reason, the movement of the suspended load LM was evaluated with or without this load swing constraint. The evaluation assumes that the undulation angle θ ₃ is 45 degrees, and the other conditions are shown in Table 3 below.

Turning angle θ to the target position (target turning angle θ _f4 ), which is calculated from Equations 4, 5, 9, 10 and 11 (first dynamics model) based on the above conditions. ₄ and turning angular velocity θ' ₄ 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 consideration (the same applies to the figures to be described later). On the other hand, in FIGS. 8 and 9, "No sway" is the calculation result when there are no constraints (load swing constraints) on the four lower sway angles θ ₁ in the radial direction and the swing angle θ ₂ in the turning direction in Equation 11. Equivalent (same for the following figures). As shown in FIG. 8, when there is no load swing constraint, the suspended load LM reaches the target position earlier than when there is a load swing constraint. However, in this case, as shown in FIG. 9, the turning angular velocity .theta.'4 of the turning body ₁₂ abruptly increases from the start of turning, and also abruptly decreases immediately before reaching the target position. For each of the above calculations, the calculation time until the optimization was completed was 1.50 seconds for "No sway" and 2.99 seconds for "With sway".

Furthermore, to confirm the validity of the temporally optimized trajectory generated above, by applying Equation 9 to Equations 2 and 3, the radial deflection angle θ ₁ of the suspended load LM and the transition of the swing angle _θ2 in the turning direction. FIG. 10 is a graph showing the temporal transition of the radial deflection angle in this embodiment. FIG. 11 is a graph showing the time course of the swing angle in the turning direction in this embodiment. Both the graphs of FIGS. 10 and 11 also show load swing after the suspended load LM reaches the target position (see arrival time in FIG. 8).

As shown in FIGS. 10 and 11, when there is a load swing constraint condition, both the radial swing angle θ ₁ and the turning direction swing angle θ ₂ are low during movement, at the target position, and after reaching the target position. suppressed. On the other hand, when there is no load swing constraint, the suspended load LM reaches the target position quickly as shown in FIG. was taken.

Furthermore, by applying the above calculation results to Equation 1, the presence or absence of load swing constraint conditions was evaluated with respect to the torque of the swing motor that swings the swing body 12 . FIG. 12 is a graph showing the time course of the turning torque τ4 in this embodiment. In FIG. 12, a part of the torque curve is shown partially enlarged. As shown in FIG. 12, whether there is a load swing constraint or not, between the maximum torque and the minimum torque of the swing motor preset in the crane 10 (the upper and lower dashed lines in FIG. 12) The result was within the range of By using Equation 1 as a constraint condition, it is possible to generate a polynomial trajectory that suppresses the turning torque τ4 between the maximum torque and the minimum torque.

<Results of verification of load swing suppression>
Next, for the first dynamics model (Example 2) and the second dynamics model (Example 1) described above, the results of optimization calculations performed in two cases as the constraint conditions included in Equation 11 are shown. . Table 4 shows two cases (Case 1, Case 2) of the above constraints.

Compared to Case 1, in Case 2, the maximum turning angular velocity θ′ _max4 , the allowable load swing angular speed during movement θ′ _SW , and the final allowable load swing angle θ _f are set relatively large. _θ'f is set relatively small. 13 and ₁₄ are graphs showing time transitions of the turning angle θ4 and the turning angular velocity _θ′4 in Case 1 above. _In case 1, there is no significant difference in the transition of the turning angle θ4 between the first embodiment and the second embodiment, but the turning angular velocity _θ′4 shows a gentler transition in the second embodiment. As a result, the top speed can be suppressed.

15 and 16 are graphs showing time transitions of the turning angle θ4 and the turning angular velocity _θ′4 in case ₂ above. In Case 2, Example 2 reached the target position earlier than Example 1. Although there is a difference in arrival time, there is no significant difference in the profile of the turning angular velocity _θ'4 .

17, 18, 19 and 20 show the respective values of the radial deflection angle θ ₁ , the radial deflection angular velocity θ′ ₁ , the turning direction deflection angle θ ₂ and the turning direction deflection angular velocity θ′ ₂ in Case 1 above. It is a graph which shows time transition. In each figure, in addition to the results of Examples 1 and 2, for confirmation, the transition when the above-mentioned complete dynamics model (Equation 2, Equation 3) is applied is shown in Example 1', Each is shown as Example 2'. Note that the discontinuous portions (ends) of the respective graphs of Examples 1 and 2 correspond to the arrival times at the target positions. Example 1' and Example 2' can evaluate the transition after reaching the target position. As shown in each figure, in the second embodiment, the load swing at the target position and the subsequent load swing are kept lower than in the first embodiment. In addition, Example 1 showed a very high degree of agreement with the complete dynamics model (Example 1'). However, in both Embodiments 1 and 2, it is possible to suppress the swing of the load at the target position to a predetermined threshold angle or less, and to allow the suspended load LM to reach the target position in the optimum minimum time. Become.

21, 22, 23 and 24 show the respective values of the radial deflection angle θ ₁ , the radial deflection angular velocity θ′ ₁ , the turning direction deflection angle θ ₂ and the turning direction deflection angular velocity θ′ ₂ in Case 2 above. It is a graph which shows time transition. Also in case 2, the load swing at the target position and the subsequent load swing are kept lower in the second embodiment than in the first embodiment. In addition, Example 1 showed a very high degree of agreement with the complete dynamics model (Example 1'). In addition, in both Embodiments 1 and 2, it is possible to suppress the swing of the load at the target position to a predetermined threshold angle or less, and to allow the suspended load LM to reach the target position in the optimum minimum time. Become.

The crane 10 according to one embodiment of the present invention has been described above. According to such a configuration, it is possible to efficiently move the suspended load LM to the target position while suppressing swinging of the suspended load LM at the target position, during the turning motion, or both. In addition, this invention is not limited to these forms. The present invention can take the following modified embodiments, for example.

(1) The structure of the crane 10 is not limited to that shown in FIG. 1, and cranes having other structures may be used. The crane 10 may have a jib connected to the tip of the boom 16, or the crane 10 may be a tower crane or the like. Also, instead of the mast 20, the crane 10 having a gantry may be used.

(2) The equation of motion of the suspended load LM used in the calculations executed by the target speed calculator 702 is not limited to that used in the previous embodiment. Other equations of motion of the suspended load LM for each of the turning and radial directions, including the length of the boom 16, the length of the main hoist rope 50, and the hoisting angle of the boom 16, may be employed. In this case, regarding the determination of the coefficients of the polynomial function for the turning angle, the complete dynamics model based on the well-known Newton's equation of motion and Lagrangian's equation of motion in addition to Equation I, Equation II, or Equation III and IV , or an equation of motion in which any minute term is eliminated from the complete dynamics model.

(3) In the above embodiment, the conditions for the radial direction deflection angle θ ₁ and the turning direction deflection angle θ ₂ are respectively set in Equation 11 both at the target position and during the turning movement. The invention is not limited to this. The swing angle condition may be set only for the target position, or may be set only during turning movement.

10 Crane 12 Rotating body (upper body)
13 counterweight 14 running body (lower body)
15 cab 16 boom (rolling body)
20 Mast 24 Boom guy line 30 Boom hoisting winch 34 Main hoisting winch 38 Boom hoisting rope 50 Main hoisting rope (load rope)
57 main hook 70 control unit 701 drive control unit 702 target speed calculation unit (target speed setting unit)
703 command signal generation unit 704 storage unit 71 swing drive unit 72 boom drive unit 73 winch drive unit 74 swing operation unit 75 boom operation unit 76 winch operation unit 81 input unit (movement information reception unit)
82 turning angle detection unit 83 hoisting angle detection unit 84 rope length detection unit (rope length information acquisition unit)
85 Boom length acquisition unit (elastic body length information acquisition unit)
86 Suspended load load detection unit 87 Display unit LM Suspended load θ ₁ Radial direction swing angle θ ₂ Rotating direction swing angle θ ₃ Luffing angle θ ₄ Rotating angle

Claims (7)

a lower body;
an upper main body supported by the lower main body so as to be pivotable around a central pivot axis extending in the vertical direction;
an undulating body including an undulating body base end portion supported by the upper body so as to be rotatable in the undulating direction around a horizontal rotation center axis;
a suspended load rope suspended from the tip of the undulating body and connected to a suspended load;
a turning drive unit capable of receiving a predetermined speed command signal and turning the upper body around the turning center axis at a speed corresponding to the speed command signal;
an undulating body length information acquisition unit for acquiring undulating body length information, which is information corresponding to the length of the undulating body in the longitudinal direction of the undulating body, which is the direction connecting the base end of the undulating body and the tip of the undulating body;
a turning angle detection unit that detects a turning angle of the upper body about the turning central axis;
a hoisting angle detection unit that detects the hoisting angle of the hoisting body about the rotation center axis;
a rope length information acquisition unit that acquires rope length information that is information corresponding to the length of the suspended load rope between the tip of the undulating body and the suspended load;
It includes a target turning angle for moving the load from an initial state in which the load is lifted by the load rope to a predetermined target position by turning the upper body about the center axis of turning. a movement information reception unit that receives movement information;
The angle of the hoisting body with respect to the vertical direction of the load rope when viewed along the turning direction of the upper body is the radial swing angle, and the hoisting body is viewed along the radial direction of the turning movement of the upper body. If the angle of the load rope with respect to the vertical direction in this case is defined as the turning direction deflection angle, the turning direction and the radial direction including at least the length of the hoisting body, the length of the lifting rope, and the hoisting angle an equation of motion of the suspended load; and a polynomial function of the swing angle of the upper body with the elapsed time of the swing motion as a variable, the polynomial function consisting of a plurality of monomials each including a different degree of the elapsed time. the radial direction swing angle and the swing direction swing angle at least one of the target position and during the swing motion are smaller than a predetermined threshold angle and the time required for the suspended load to reach the target position is a target speed setting unit that determines each of the coefficients of the plurality of monomials so as to be the minimum, and sets a target speed according to the elapsed time of the upper body until reaching the target position;
a command signal generator that generates and outputs the speed command signal corresponding to the target speed set by the target speed setting unit;
Crane with. 2. The crane according to claim 1, wherein said command signal generating section inputs said generated speed command signal to said turning driving section. 3. The target speed setting unit according to claim 1 or 2, wherein the coefficients of the plurality of monomial equations are respectively determined such that the radial deflection angle and the turning direction deflection angle at the target position are smaller than a predetermined threshold angle. Crane as described. The target speed setting unit further sets the turning speed of the upper body to zero when the suspended load reaches the target position, and changes the radial direction deflection angle and the turning direction deflection angle over time. 4. The crane according to any one of claims 1 to 3, wherein the coefficients of the plurality of monomial expressions are respectively determined so that the radial swing angular velocity and the turning direction swing angular velocity are equal to or less than a predetermined threshold angular velocity at the target position. The target speed setting unit further sets the movement speed of the upper body to a predetermined maximum speed or less during the turning motion, and the radial direction deflection angle and the turning direction deflection angle are predetermined maximum angles during movement. 5. The method according to any one of claims 1 to 4, wherein the coefficients of the plurality of monomial expressions are respectively determined so that the radial swing angular velocity and the swing angular velocity in the turning direction are equal to or less than a predetermined maximum angular velocity during movement. Crane as described. The crane according to any one of claims 1 to 5, wherein the target speed setting unit sets the target speed based on Equations I and II below as equations of motion for the suspended load.
θ'' ₁ = 2 × θ' ₂ × θ' ₄ + θ ₂ × θ'' ₄ + θ ₁ × θ' ₄ ² + (L/l) × θ' ₄ ² × sin θ ₃ - (g/l) × θ ₁ (Formula I)
θ″ ₂ =−(L/l)×θ″ ₄ ×sin θ ₃ −2×θ′ ₁ ×θ′ ₄ −θ ₁ ×θ′ ₄ +θ ₂ ×θ′ ₄ ² −(g/l) θ ₂ (formula II)
(However, θ ₁ : radial swing angle of suspended load, θ ₂ : swing angle of suspended load in turning direction, θ′ ₁ : radial swing angular velocity of suspended load, θ′ ₂ : swing angular speed of suspended load in swing direction, θ '' ₁ : Radial direction swing angular acceleration of the suspended load, _θ''2 : Rotating direction swing angular acceleration of the suspended load, θ3: Luffing angle of the undulating body with respect to the vertical direction, _θ′4 : _Rotating angular velocity of the upper body , θ″ ₄ : turning angular acceleration of the upper body, g: gravitational acceleration, L: length of the undulating body, l: length of the lifting rope from the tip of the undulating body to the suspended load) The crane according to any one of claims 1 to 5, wherein the target speed setting unit sets the target speed based on Equations III and IV below as equations of motion for the suspended load.
θ″ ₁ =2×θ′ ₂ ×θ′ ₄ +(L/l)×θ′ ₄ ² ×sin θ ₃ −(g/l)×θ ₁ (formula III)
θ″ ₂ =−(L/l)×θ″ ₄ ×sin θ ₃ −(g/l) θ ₂ (formula IV)
(However, θ ₁ : radial swing angle of suspended load, θ ₂ : swing angle of suspended load in turning direction, θ′ ₂ : swing angular velocity of suspended load in swing direction, θ″ ₁ : radial swing angular acceleration of suspended load , θ″ ₂ : swaying angular acceleration of the suspended load in the turning direction, θ ₃ : undulation angle of the undulating body with respect to the vertical direction, θ′ ₄ : turning angular velocity of the upper body, θ″ ₄ : turning angle of the upper body acceleration, g: gravitational acceleration, L: length of the undulating body, l: length of the rope from the tip of the undulating body to the suspended load)

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