A method and system for acquiring the position and orientation of a crane's controlled object, and a crane

Abstract

The present invention provides a method and system for acquiring the position and orientation of a crane's controlled object, and a crane itself, which can acquire the position and orientation of the controlled object sequentially from an earlier stage, regardless of its positional relationship with the object it is landing on. [Solution] In the method for acquiring the position and orientation of the crane's controlled object, at least three or more position and orientation acquisition devices (2a, 2b, 3, 4) installed on the structure 11, trolley 12, and lifting device 13 respectively acquire position and orientation data D3, which is a collection of multiple measurements in each of the following coordinate systems: reference coordinate system ΣGmn, structure coordinate system ΣLA, ΣLB, trolley coordinate system ΣT, and lifting device coordinate system ΣS, for the position and orientation of the structure 11, the trolley 12, and the lifting device 13. Each time position and orientation data D3 is acquired, the arithmetic unit 5 performs data processing using multiple coordinate transformation matrices and the position and orientation data D3 to acquire the position and orientation of the controlled object Ca in the reference coordinate system ΣGmn.

Description

[Technical Field]

[0001] The present invention relates to a method and system for acquiring the position and orientation of a crane's controlled object, and to a crane, and more particularly to a method and system for acquiring the position and orientation of a crane's controlled object that can sequentially acquire the position and orientation of the crane's lifting device or the load lifted by the lifting device and the object to which they are to be placed, from an earlier stage, regardless of the positional relationship between the two. [Background technology]

[0002] In the crane device proposed in Patent Document 1, the position of the stacked container is measured by position detection units such as optical cameras and laser sensors installed on the spreader and trolley. In this crane device, position and orientation adjustment is performed based on the relative position of the object to be loaded, which is directly measured using a coordinate system based on the spreader and trolley. Therefore, position and orientation adjustment using relative position, as in this crane device, is performed after the spreader or trolley and the object to be loaded have been brought close enough that the position of the object to be loaded can be measured.

[0003] However, when adjusting the position and orientation of the spreader or trolley after bringing it close to the object to be landed, the relative positional displacement between the two becomes large, resulting in a large and frequent adjustment of the lifting equipment. As a result, the lifting equipment swings, and it cannot be landed until the swing subsides, thus preventing a reduction in the time required for cargo handling. To further reduce the relative positional displacement just before landing, it is effective to acquire the position and orientation of the lifting equipment and the lifted load earlier and perform positional adjustment. Therefore, further development is needed to acquire the position and orientation of the crane's lifting equipment or the load lifted by the lifting equipment and the object to be landed on from an earlier stage, regardless of their positional relationship. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication Number WO2019 / 008914 [Overview of the project] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a method and system for acquiring the position and orientation of a crane's controlled object, as well as a crane, that can acquire the position and orientation of the crane's lifting device or the load lifted by the lifting device and the target to which they are to be lowered, from an earlier stage, regardless of the positional relationship between the two. [Means for solving the problem]

[0006] The present invention provides a method for acquiring the position and orientation of a crane's controlled object, which achieves the above objective. The method comprises a structure having a traveling device, a movable part that operates in contact with the structure, and a lifting device that operates suspended from the movable part via a cable-like material. In this method, the lifting device or a load lifted by the lifting device is used as the controlled object during cargo handling, and the position and orientation of the controlled object is acquired. The method uses a three-dimensional orthogonal coordinate system as the reference coordinate system, where the origin is fixed on the ground where the load is stored, and one of the coordinate axes is the vertical line. The origins of the three-dimensional orthogonal coordinate system are fixed to the structure, the movable part, and the lifting device, respectively, and the coordinate axes of the three-dimensional orthogonal coordinate system change in accordance with the position and orientation of the structure, the movable part, and the lifting device. The system is characterized in that, when cargo handling is performed by the crane, position and orientation data is sequentially acquired by at least three or more position and orientation acquisition devices installed on the structure, the movable part, and the lifting device, which are measured values ​​in each of the coordinate systems of the reference coordinate system, the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system, respectively, as the position and orientation of the structure, the position and orientation of the movable part, and the position and orientation of the lifting device, and each time the position and orientation data is acquired, the system performs data processing using multiple coordinate transformation matrices from each of the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system to the reference coordinate system and the position and orientation data, thereby acquiring the position and orientation of the controlled object in the reference coordinate system.

[0007] The crane control object position and orientation acquisition system of the present invention acquires the position and orientation of a control object, with the lifting device or the load lifted by the lifting device as the control object during cargo handling by a crane comprising a structure having a traveling device, a movable part that operates in contact with the structure, and a lifting device that operates suspended from the movable part via a cable-like material, and the reference coordinate system is a three-dimensional orthogonal coordinate system in which the origin is fixed on the ground where the load is stored and one of the coordinate axes is the vertical line, and the origins of the three-dimensional orthogonal coordinate system are fixed on the structure, the movable part, and the lifting device, respectively, and the coordinate axes of the three-dimensional orthogonal coordinate system are defined as the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system, respectively, with the origins of the structure, the movable part, and the lifting device being fixed on the structure, the movable part, and the lifting device. The system comprises at least three position and orientation acquisition devices installed on each of the parts and the lifting device, which sequentially acquire position and orientation data in which multiple measurements are accumulated in the respective coordinate systems of the reference coordinate system, the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system, respectively, as the position and orientation of the structure, the position and orientation of the movable part, and the position and orientation of the lifting device, and a calculation device, wherein the calculation device has a storage unit that stores multiple coordinate transformation matrices from each of the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system to the reference coordinate system, and each time the position and orientation data is acquired, the calculation device performs data processing to acquire the position and orientation of the controlled object in the reference coordinate system based on the multiple coordinate transformation matrices and the position and orientation data.

[0008] The crane of the present invention is characterized by comprising a system for acquiring the position and attitude of the object controlled by the crane. [Effects of the Invention]

[0009] According to the present invention, by utilizing position and orientation data acquired sequentially during crane loading and unloading, the position and orientation of the controlled object in the reference coordinate system can be acquired sequentially, eliminating the need to directly measure the position of the object to be loaded. Therefore, the position and orientation of the controlled object in the reference coordinate system can be acquired sequentially even before the position of the object to be loaded can be directly measured, and position and orientation matching with the object to be loaded can be started earlier using the acquired position and orientation.

[0010] Furthermore, in cranes, the position and orientation of each part of the structure, movable parts, and lifting equipment change dynamically moment by moment due to external disturbances such as uneven loads and wind during the operation of the movable parts and lifting equipment. According to the present invention, by sequentially acquiring the position and orientation of the controlled object in the reference coordinate system, it is possible to capture these dynamic changes. [Brief explanation of the drawing]

[0011] [Figure 1] This is an explanatory diagram illustrating an embodiment of a crane and a system for acquiring the position and attitude of a controlled object. [Figure 2] This is a flowchart illustrating the procedure for controlling a crane. [Figure 3] This is an explanatory diagram illustrating map data. [Figure 4] This is a flowchart illustrating the procedure for step S110 in Figure 2. [Figure 5] This is an explanatory diagram illustrating the designated section and target value in a given subsection number. [Figure 6] Step S130 in Figure 2 is a flowchart illustrating the procedure of an embodiment of the method for acquiring the position and orientation of the crane's controlled object. [Figure 7] This is an explanatory diagram illustrating the coordinate systems and position vectors for the reference coordinate system, structural coordinate system, trolley coordinate system, and suspension device coordinate system. [Figure 8] This is an explanatory diagram illustrating structural data. [Figure 9] This is an explanatory diagram illustrating position and orientation data. [Figure 10]This is an explanatory diagram illustrating a part of the position and attitude acquisition system in the modified example 1. [Figure 11] This flowchart illustrates the procedure for controlling a crane, including the method for acquiring its position and orientation (Modified Example 1). [Figure 12] This is a cross-section illustrating the position and orientation acquisition system in modified example 2. [Figure 13] This is an explanatory diagram illustrating a part of the position and orientation acquisition system in modified example 3. [Figure 14] This flowchart illustrates the procedure for acquiring position and orientation in modified example 3. [Figure 15] This graph illustrates the displacement of the suspension device and the acceleration of the trolley over time. [Figure 16] This flowchart illustrates the procedure for controlling a crane, including the method for acquiring its position and orientation (Modified Example 4). [Figure 17] This is an explanatory diagram illustrating actual measured data. [Figure 18] This is an explanatory diagram illustrating different measured data. [Modes for carrying out the invention]

[0012] The method and system for acquiring the position and orientation of a crane's controlled object, as well as the crane itself, will be described below based on the embodiments shown in the figures.

[0013] The embodiment of the position and orientation acquisition system 1 illustrated in Figure 1 comprises a position and orientation acquisition device (2a, 2b, 3, 4) and a calculation device 5. This position and orientation acquisition system 1 is mounted on a crane 10 that handles containers Ct as cargo at a container terminal. This position and orientation acquisition system 1 enables the implementation of an embodiment of the crane's controlled object position and orientation acquisition method illustrated in Figure 6. This position and orientation acquisition method is used to acquire the position and orientation of the controlled object Ca when the crane 10 is using a lifting device 13 or a container Ct lifted by the lifting device 13 as the controlled object Ca to be laid down in a designated area Da which is the landing target.

[0014] This section outlines the position and orientation acquisition method. This method is implemented as part of the control method for the crane 10 illustrated in Figure 2. Specifically, step S130, which acquires the control amount Cv in the position and orientation adjustment process S120, corresponds to this position and orientation acquisition method. As illustrated in Figure 6, in the procedure of this position and orientation acquisition method (step S130), position and orientation data D3 is acquired by the position and orientation acquisition device (2a, 2b, 3, 4) (S131). Subsequently, each time position and orientation data D3 is acquired, data processing is performed using multiple coordinate transformation matrices (see equation (2) below), pre-determined structural data D2, and position and orientation data D3, and a position vector is obtained as the position and orientation of the controlled object Ca in the reference coordinate system ΣGmn. G C (see formula (6) or (7) below) and integrated skew angle G ζ C (See formula (11) below) and are calculated (S132). The calculated position vector G C and integrated skew angle G ζ C This is the control amount Cv in the position and orientation adjustment process S120. Finally, as illustrated in Figure 2, the calculated control amount Cv is used to operate the trolley 12 and the lifting device 13 (S140, S150) to bring the controlled object Ca to the designated area Da (S160).

[0015] First, we will describe the embodiment of the crane 10, the container terminal, and the position and orientation acquisition system 1 in detail.

[0016] The crane 10 illustrated in Figure 1 can be any known type of crane, such as a gantry crane, transfer crane, or jib crane. This crane 10 is a transfer crane (gantry crane) that crosses over and travels along the storage lane SL present in a container terminal. The crane 10 may also be a crane used for handling cargo other than containers Ct at a known logistics facility other than a container terminal. Examples of logistics facilities include warehouses for temporarily storing cargo and steel plate manufacturing facilities for manufacturing and shipping steel plates.

[0017] The crane 10 comprises a structure 11, a trolley 12, a lifting device 13, a traveling device 14, a traversing device 15, a lifting device 16, and a fine adjustment device 17. The trolley 12 corresponds to a movable part that operates in contact with the structure 11 of the present invention.

[0018] The structure 11 has multiple running gears 14, a girder 18 extending in the direction (Y direction) that crosses the storage lane SL, and multiple legs 19 to which running gears 14 are attached at the lower end and whose upper ends are connected by the girder 18. The structure 11 travels in the direction of travel (X direction) by the multiple running gears 14, and the multiple running gears 14 are in contact with the ground (yard surface). The multiple running gears 14 are arranged on both the side of one end and the side of the other end of the girder 18. The running gears 14 have multiple tires that roll on the ground of the container terminal, but may also have multiple wheels that roll on rails laid in the container terminal. The running gears 14 only need to be able to drive those tires or wheels, and for example, they have an inverter, an electric motor driven by power supplied from the inverter, and a reduction gear that transmits the rotational power of the electric motor to those tires or wheels.

[0019] The trolley 12 moves along the girder 18 in the traverse direction (Y direction) by a traverse device 15. The traverse device 15 has, for example, a plurality of wheels positioned at the lower end of the trolley 12 that roll along rails laid along the girder 18. The traverse device 15 only needs to be able to operate the trolley 12 by rolling these wheels, and has an inverter, an electric motor driven by power supplied from the inverter, and a reduction gear that transmits the rotational power of the electric motor to these wheels. Alternatively, the traverse device 15 may have a drum that winds up and unwinds a cable-like body (wire rope) connected to the trolley 12, and the plurality of wheels may be rolled by rotating the drum with an electric motor to wind up and unwind the cable-like body.

[0020] The lifting device 13 is suspended from the trolley 12 via a cable-like material (wire rope). The lifting device 16 has a drum for winding in and unwinding the cable-like material. The lifting device 16 only needs to be able to rotate its drum and has an inverter, an electric motor driven by power supplied from the inverter, and a reduction gear that transmits the rotational power of the electric motor to the drum.

[0021] The traverse device 15 and the lifting device 16 may be integrated into a common moving device for the trolley 12 and the lifting device 13. This type of common moving device has, for example, four drums in a four-drum bridge-type unloader, each driven by an inverter motor. The traverse device 15 and the lifting device 16 may be installed on the structure 11 or on the trolley 12.

[0022] The number of cable-like bodies supporting the suspension device 13 and the number of drums in the lifting device 16 are not particularly limited and are appropriately selected according to the degree of freedom of operation of the suspension device 13. For example, if the number of cable-like bodies is four and the number of drums is four, the degree of freedom of operation of the suspension device 13 by the lifting device 16 will be six degrees of freedom: translation in the X, Y, and Z directions, trim (rotation around the Y axis), ripping (rotation around the X axis), and skew (rotation around the Z axis). Also, if the number of cable-like bodies is four and the number of drums is two, the degree of freedom of operation of the suspension device by the lifting device 16 will be two degrees of freedom: translation in the Z direction and trim or ripping.

[0023] The fine adjustment device 17 can use various known actuators installed on the trolley 12 or the suspension device 13. Furthermore, the fine adjustment device 17 can also use various known anti-sway devices to suppress vibrations in the suspension device 13, and the actuator and anti-sway device may be used in combination. The fine adjustment device 17 causes tension or slack in the cable-like structure that suspends and supports the suspension device 13, and the resulting tension or slack in the cable-like structure causes the suspension device 13 to move slightly. Multiple fine adjustment devices 17 are provided. For example, if there are four cable-like structures that suspend and support the suspension device 13, two fine adjustment devices 17 are provided, and each fine adjustment device 17 connects the ends of a pair of cable-like structures. Each fine adjustment device 17 causes tension or slack in one of the pair of cable-like structures, or in both cable-like structures. The degree of freedom of the operation of the suspension device 13 by the fine adjustment device 17 may be one degree of freedom due to skew, but it is desirable to have two or more degrees of freedom that include at least translation in the X direction and skew.

[0024] A container terminal stores numerous containers Ct in numerous storage lanes SL. In each storage lane SL, numerous containers Ct are arranged in the longitudinal direction (X direction), the short direction (Y direction), and the vertical direction (Z direction) of the containers Ct. The longitudinal direction of the storage lane SL is oriented toward the longitudinal direction of the containers Ct, and the short direction of the storage lane SL is oriented toward the short direction of the containers Ct. The arrangement of containers Ct in the storage lane SL is called a bay for the X direction, a row for the Y direction, and a tier for the Z direction. Each storage lane SL has numerous compartments D pre-configured for storing containers Ct. In the example shown, the thin dashed rectangles represent compartments D, and the compartments D filled with diagonal lines represent designated compartments Da.

[0025] Section D has a shape similar to the cargo to be handled by crane 10, and its position and orientation virtually represent the position and orientation of cargo stacked in a desired arrangement. Each section D in the illustrated example is a rectangular parallelepiped, similar to container Ct, and virtually represents the position and orientation of container Ct that is to be stored on the ground (yard surface) of the container terminal. The position and orientation of section D uses the reference coordinate system ΣGmn, exemplified in Figure 5 described later, as a local three-dimensional Cartesian coordinate system with its origin on the ground (yard surface) of the container terminal. The position and orientation of section D includes at least the two-dimensional position coordinate of the center of the bottom surface of section D and the skew angle with a vertical line passing through that center as the axis of rotation. Each section D is divided by a designation number (1111~mnij) consisting of lane number (1~m), bay number (1~n), row number (1~i), and tier number (1~j). Therefore, the position and orientation of container Ct in the storage lane SL are managed by its designated number (1111~mnij).

[0026] Designated section Da is section D intended for the landing of the controlled object Ca. Designated section Da is selected from among the sections D by a management system (not shown) that manages containers Ct at the container terminal, and the management system instructs the position and orientation acquisition system 1 of the target crane 10 to select it.

[0027] The position and orientation acquisition system 1 is mounted on each crane 10 of the container terminal. This position and orientation acquisition system 1 functions, for example, as part of an automated system that performs data processing to automatically control the operation of the crane 10. The automated system may consist of the position and orientation acquisition system 1 and the control system that controls the operation of the crane 10 as separate components, or, as in this embodiment, the position and orientation acquisition system 1 and the control system that controls the operation of the crane 10 may be integrated into a single unit.

[0028] The position and attitude acquisition devices (2a, 2b, 3, 4) are installed on the crane 10. The position and attitude acquisition devices (2a, 2b, 3, 4) sequentially acquire position and attitude data D3, which is accumulated from multiple measurements in the reference coordinate system ΣGmn, the structure coordinate system ΣLA, ΣLB, the trolley coordinate system ΣT, and the lifting device coordinate system ΣS, as the position and attitude of the structure 11, the trolley 12, and the lifting device 13. The position and attitude data D3 will be described later. The position and attitude acquisition devices (2a, 2b, 3, 4) consist of multiple devices that can directly or indirectly acquire the three-dimensional position coordinates and skew angles of each part of the structure 11, the trolley 12, and the lifting device 13. The multiple devices can be various known devices such as radio wave positioning devices (including devices that use GNNS), self-position estimation devices, inertial navigation devices, rangefinders, and inclinometers, and are not limited to one type of device, but may be a combination of multiple types of devices. In this embodiment, the structural position and orientation acquisition devices 2a and 2b are installed on the structure 11, the movable part position and orientation acquisition device 3 is installed on the trolley 12, and the suspension device position and orientation acquisition device 4 is installed on the trolley 12 and the suspension device 13, respectively.

[0029] The arithmetic unit 5 receives and stores various data, and performs data processing using this data. The arithmetic unit 5 can use various known computers. The arithmetic unit 5 has an arithmetic processing unit 5a (CPU), a main memory unit 5b (memory), an auxiliary storage unit 5c (for example, an HDD), etc. The auxiliary storage unit 5c corresponds to the storage unit of the present invention and stores map data D1, structure data D2, position and orientation data D3, target value TP, and control variable Cv.

[0030] Next, the control method for the crane 10 will be described. This control method is performed in order to land the controlled object Ca in the designated area Da.

[0031] Figure 2 shows an example of the procedure for controlling the crane 10, and step S130 of this procedure corresponds to the embodiment of the method for acquiring the position and orientation of the crane's controlled object illustrated in Figure 6. In this control method, the position and orientation adjustment process S120 is repeatedly performed every period T [ms] from the start of operation of the trolley 12 until the controlled object Ca is brought to rest in the designated section Da. In the procedure of the control method, once the target value TP is acquired (S110), the position and orientation adjustment process S120 is performed. In the procedure of the position and orientation adjustment process S120, the embodiment of the position and orientation acquisition method is performed and the control amount Cv (position and orientation of the controlled object Ca) is acquired in the same coordinate system as the target value TP (S130). Next, operation commands for the trolley 12 and the lifting device 13 are created to match the control amount Cv to the target value TP (S140), and the trolley 12 and the lifting device 13 are operated based on their respective operation commands (S150). Then, the position and orientation adjustment process S120 is repeated until the controlled object Ca settles in the predetermined section Da (S160:YES), at which point this control method ends.

[0032] In this example, the operation of the trolley 12 is traversal in the Y direction by the traversing device 15. The operation of the suspension device 13 is descent by the lifting device 16 and movement of the suspension device 13 in the X direction and rotation around the vertical line by the fine adjustment device 17. Therefore, in this example, the degree of freedom of movement of the controlled object Ca is four degrees of freedom.

[0033] The position and orientation adjustment process S120 begins when the movement of the structure 11 by the traveling device 14 stops and the trolley 12 starts operating. For example, when the container Ct is lifted by the lifting device 13, the control target Ca rises to a predetermined position and the trolley 12 begins to move horizontally before step S130, which is the position and orientation acquisition method of the present invention, is executed.

[0034] The repetition period T of the position and orientation adjustment process S120 can be arbitrarily set within a range that is shorter than the period from the start of operation of the trolley 12 until the controlled object Ca is brought to rest in the designated section Da. The shorter the period T, the more times the position and orientation adjustment process S120 is repeated until the controlled object Ca is brought to rest, which is advantageous for improving the accuracy of position and orientation adjustment. The period T is preferably 1.0 [s] or less, and more preferably 100 [ms] or less. The sampling period of the position and orientation acquisition device (2a, 2b, 3, 4) can be used for the period T. This sampling period is, for example, 20 ms to 100 ms. By using the sampling period of the position and orientation acquisition device as the period T, the position and orientation of each part of the structure 11, trolley 12, and suspension device 13, which change dynamically moment by moment, can be captured. Therefore, this is advantageous for improving robustness.

[0035] In step S110, the target value TP is acquired. The target value TP may be acquired by being transmitted directly from the management system to the arithmetic unit 5 along with the instruction of the designated section Da for the crane 10 from the management system, or it may be acquired by data processing by the arithmetic processing unit 5a based on the instructed designation number and the map data D1 stored in the auxiliary storage unit 5c. Details of this step S110 will be described later.

[0036] In step S130, an embodiment of the position and attitude acquisition method of the present invention is implemented, and the controlled variable Cv (position and attitude of the controlled object Ca) is acquired in the same coordinate system as the target value TP. Details of this step S130 will be described later.

[0037] In step S140, the calculation processing unit 5a performs data processing to create operation commands for the trolley 12 and the lifting device 13, respectively, to match the controlled variable Cv to the target value TP. The state in which the controlled variable Cv matches the target value TP means that the difference between the controlled variable Cv and the target value TP becomes zero, that is, the controlled object Ca lands in the predetermined section Da without any displacement. Each operation command is created, for example, by decomposing the difference between the controlled variable Cv and the target value TP into four components: X direction, Y direction, Z direction, and skew. Furthermore, each operation command is created based on the amount of variation of the controlled variable Cv, assuming that the controlled variable Cv matches the target value TP. Details of creating operation commands based on the amount of variation of the controlled variable Cv will be described later.

[0038] The operation command for the trolley 12 is an operation command for the traverse device 15. This operation command is created to adjust the traverse distance of the trolley 12 so that the trolley 12 stops at a position where the Y-direction component of the difference between the controlled amount Cv and the target value TP becomes zero. In typical trolley 12 traverse, the acceleration period, rated speed period, and deceleration period are adjusted using the traverse distance from the traverse limit position to the stopping position, and the acceleration, rated speed, and deceleration, which are set to fixed values ​​in advance. The traverse limit position is, for example, p0 in Figure 6, which will be described later. The operation command for the traverse device 15 adjusts either the rated speed period or the deceleration depending on when the operation command is created. In operation commands generated outside of the deceleration period, the length of the rated speed period is adjusted. In operation commands generated during the deceleration period, the fixed deceleration is exceptionally adjusted.

[0039] The operation command for the lifting device 13 is an operation command for the lifting device 16 and the fine-adjustment device 17, respectively. The operation command for the lifting device 16 is created to adjust the descent distance of the lifting device 13 so that the lifting device 13 stops at a position where the Z-direction component of the difference between the controlled amount Cv and the target value TP becomes zero. In the descent of the lifting device 13 in general, similar to the traverse of the trolley 12, the acceleration period, rated speed period, and deceleration period are adjusted using the descent distance from the lower end of the trolley 12 to the stopping position, and the acceleration, rated speed, and deceleration which are set to fixed values ​​in advance. The operation command for the lifting device 16 adjusts either the rated speed period or the deceleration depending on when the operation command is created. In operation commands created outside of the deceleration period, the length of the rated speed period is adjusted. In operation commands created during the deceleration period, the fixed deceleration is exceptionally adjusted.

[0040] The operation command to the fine adjustment device 17 is designed to adjust the amount of movement of the suspension device 13 in the X direction, stopping the suspension device 13 at a position where the X-direction component of the difference between the controlled quantity Cv and the target value TP becomes zero. Furthermore, the operation command to the fine adjustment device 17 adjusts the angle of rotation around a vertical line passing through the center of the lower end of the suspension device 13 as the axis of rotation, thereby controlling the integrated skew angle of the controlled quantity Cv. G ζ C It is created so that it matches the skew angle of the target value TP.

[0041] In step S150, the calculation processing unit 5a performs data processing to operate the trolley 12 and the lifting device 13 based on the respective operation commands created. Specifically, the calculation unit 5 transmits the created operation commands to the traverse device 15, the lifting device 16, and the fine-movement device 17, causing the trolley 12 and the lifting device 13 to operate simultaneously by each device. Simultaneous operation means that the traverse of the trolley 12, the descent of the lifting device 13, the movement of the lifting device 13 in the X direction, and the rotation of the lifting device 13 around its vertical axis are all performed at a timing that can be considered approximately simultaneous. Depending on the operation command, only some of these operations may be performed.

[0042] In step S160, the arithmetic processing unit 5a performs data processing to determine whether the controlled object Ca has landed in the designated area Da. If it is determined that it has landed in the designated area Da (S160: YES), the repetition of the position and orientation adjustment process S120 ends. If it is determined that it has not landed in the designated area Da (S160: NO), the process returns to the above step (S130) and the position and orientation adjustment process S120 is repeated. The detection value of a known landing sensor installed on the lifting device 13 can be used for the determination. Alternatively, the determination may be based on whether the controlled amount Cv and the target value TP match. Specifically, the controlled amount Cv and the target value TP are compared to determine whether they are within the allowable range set as an approximation. The allowable range can be set arbitrarily.

[0043] The position and orientation adjustment process S120 is repeated every period T, continuously adjusting the position and orientation of the controlled object Ca and the designated area Da, until finally the controlled object Ca lands in the designated area Da. In other words, each time the position and orientation adjustment process S120 is repeated, the controlled variable Cv gradually approaches the target value TP. Furthermore, even if the controlled variable Cv fluctuates significantly during this process, each operation command is generated taking this fluctuation into account, so the fluctuation is gradually corrected. As a result, the controlled variable Cv gradually approaches the target value TP.

[0044] Thus, in the position and orientation adjustment process S120, which is repeated every period T, the trolley 12 and lifting device 13 are operated each time to adjust the position and orientation of the controlled object Ca. In other words, the position and orientation adjustment between the controlled object Ca and the designated section Da proceeds continuously in real time from an earlier stage, even before just before landing. As a result, by the time the controlled object Ca lands in the designated section Da, the position and orientation adjustment with the designated section Da is largely completed, thus reducing the positional deviation of the controlled object Ca relative to the designated section Da just before landing. This reduces the amount of operation required for position and orientation adjustment just before landing, and also reduces the frequency of such operations, thereby effectively suppressing the sway of the controlled object Ca just before landing. As a result, the time required for cargo handling is shortened, greatly contributing to improved cargo handling efficiency.

[0045] Furthermore, in the crane 10, the three-dimensional position coordinates and skew angles of the structure 11, trolley 12, and lifting device 13 change dynamically moment by moment due to disturbances such as uneven loads and wind during the operation of the trolley 12 and lifting device 13, and consequently the controlled variable Cv also changes dynamically. With this control method, by repeating the position and attitude adjustment process S120 at each period T, the control variable Cv can be adjusted by operating the trolley 12 and lifting device 13 while capturing these dynamic changes. In this way, by considering the effects of dynamic changes due to disturbances, more robust and highly accurate position and attitude adjustment can be performed.

[0046] Furthermore, this control method only requires that the position and orientation of each section D, which is a candidate for the target value TP, be obtained by measurement during the construction of the storage lane SL. Therefore, it is not necessary to install white lines or targets on the storage lane SL, which were essential in conventional methods to serve as indicators of loading. In this way, the cost and effort of installing these white lines and targets, as well as the maintenance of them, can be eliminated, which greatly contributes to a significant reduction in the cost required to maintain the container terminal.

[0047] If no restrictions are placed on the operation of the trolley 12 and lifting device 13 during the position and orientation adjustment process S120, the controlled object Ca will land in the designated area Da at the shortest distance. However, if the movement of the controlled object Ca at the shortest distance would cause a collision with another container Ct, it is advisable to restrict the operation of the trolley 12 and lifting device 13 to avoid such a collision. For example, a restriction can be placed to prohibit the lowering of the lifting device 13 until the controlled object Ca has overtaken the container Ct that could potentially collide at the shortest distance. Alternatively, a restriction can be placed to limit the lowering of the lifting device 13 so that the lower surface of the controlled object Ca does not fall below the upper surface of the container Ct. These restrictions are released when the controlled object Ca has overtaken the container Ct.

[0048] The ground (yard surface) that forms the bottom surface of each section D at the lowest level of the storage lane SL includes a horizontal plane with no inclination and an inclined surface with an inclination such as a water gradient. As methods of stacking containers Ct, there are vertical stacking in the direction of the gravity line and diagonal stacking perpendicular to the inclined surface. When the inclination of the ground of each section D is zero and it is a horizontal plane, the stacking methods of both are the same. According to this control method, regardless of the inclination of the ground, if the Z direction of the coordinate system defining the target value TP and the control amount Cv is defined to coincide with the vertical line direction (gravity line direction), vertical stacking becomes possible, and if the Z direction of that coordinate system is defined in the direction perpendicular to the ground, diagonal stacking becomes possible. Therefore, vertical stacking and diagonal stacking are selected according to the Z direction of the coordinate system. When the inclination of the ground is large, it is advisable to select vertical stacking that is mechanically stable. Hereinafter, the stacking method of the container Ct will be described using the case of vertical stacking.

[0049] Next, an example of the above-described step S110 will be described. In this step S110, the designated numbers (1111~mnij) instructed from the management system and the map data D1 illustrated in FIG. 3 described later are used.

[0050] The map data D1 illustrated in FIG. 3 is stored in advance in the auxiliary storage unit 5c of the arithmetic unit 5. The map data D1 is a table data in which the two-dimensional position coordinates and skew angles for each partial number (111~mni) composed of the lane number (1~m), bay number (1~n), and row number (1~i), which are a part of the designated number, are accumulated as candidates for the target value TP of the designated section Da. This map data D1 uses the reference coordinate system ΣGmn as the coordinate system.

[0051] Specifically, the map data D1 accumulates the two-dimensional position coordinates and skew angles for the partial numbers (111, ···, 11i, ···) in the leftmost column of the table. Also, the map data D1 has different reference coordinate systems ΣGmn set for each combination number (11~mn) composed of a part of the partial number, the lane number (1~m), and the bay number (1~n). The two-dimensional position coordinates ((0, Y 111 )、···、(0,Y 11iThe skew angles (0, 0, 0) and the reference coordinate system ΣGmn corresponding to the combination number are measured individually. For example, the two-dimensional position coordinates (0, Y) of sub-number (111) are measured using a reference coordinate system ΣGmn corresponding to the combination number. 111 The skew angle (0) of ) is measured using the reference coordinate system ΣG11.

[0052] The centers of the lower surfaces of sections D with the same section number lie on the same vertical line. Therefore, the two-dimensional position coordinates for each section number represent the two-dimensional position coordinates of that vertical line. The skew angle represents the rotation angle around that vertical line.

[0053] The reference coordinate system ΣGmn can be arbitrarily set as long as the origin is fixed to the ground (yard surface) of the container terminal, but a three-dimensional orthogonal coordinate system in which the origin gmn is fixed to the ground (road surface) on which the running device 14, adjacent to the side of the storage lane SL, travels is preferred. The Z axis of the reference coordinate system ΣGmn is the vertical line (gravity line). The X axis indicates the direction of extension of the storage lane SL (the direction of travel of the crane 10), that is, the longitudinal direction of the container Ct stored in the storage lane SL. The Y axis indicates the direction perpendicular to the direction of extension of the storage lane SL, that is, the traverse direction of the trolley 12 and the short direction of the container Ct stored in the storage lane SL, and indicates a straight line passing through the center of the lower surface of sections D with the same combination number in a plan view.

[0054] The reference coordinate system ΣGmn is preferably set for each storage lane SL, and more preferably for each combination number. Sections D with the same combination number have their respective bottom surfaces centered on a line perpendicular to the direction of extension of the storage lane SL in a plan view. Therefore, each reference coordinate system ΣGmn set for each combination number uses the vertical line and the line perpendicular to it as axes of the coordinate system, making it possible to more easily represent the three-dimensional position coordinates and skew angle of section D. In the illustrated example, since the bottom surfaces of sections D with the same combination number are each located on the Y axis, the X coordinate is "0". The Y coordinate differs for each row number (1 to i). Also, since the X axis of the reference coordinate system ΣGmn indicates the longitudinal direction of the container Ct and the Y axis indicates the short direction of the container Ct, the skew angle using the reference coordinate system ΣGmn is "0".

[0055] Map data D1 can be created simply by defining the two-dimensional position coordinates and skew angle for each sub-number using the reference coordinate system ΣGmn for each combination number. In other words, map data D1 can be created more easily during container terminal construction without the need to actually stack containers Ct or measure the two-dimensional position coordinates and skew angle. Furthermore, by using the reference coordinate system ΣGmn as the local three-dimensional Cartesian coordinate system, map data D1 can represent the X-coordinate and skew angle as "0", which is advantageous in reducing the processing load in calculating operation commands.

[0056] Map data D1 may contain a collection of three-dimensional position coordinates and skew angles for each specified number. In this case, steps S113 and S114, illustrated in Figure 4 above, can be omitted. In this case, the Z coordinate for each specified number can be calculated using the procedure of steps S113 and S114, eliminating the need to actually stack the containers Ct and take measurements.

[0057] Step S110, illustrated in Figure 4, is executed when the designated number of a designated section Da instructed by the management system is input to the arithmetic unit 5. In this step S110, the arithmetic processing unit 5a selects a sub-number from the input designated number (S111), and uses the map data D1 to obtain the two-dimensional position coordinates and skew angle corresponding to that selected sub-number (S112). Next, the arithmetic processing unit 5a selects a tier number from the input designated number (S113), and uses the selected tier number to calculate the Z coordinate (S114). Finally, the obtained two-dimensional position coordinates and skew angle, along with the calculated Z coordinate, are obtained as the target value TP.

[0058] The Z coordinate is calculated as the height in the Z direction from the XY plane of the reference coordinate system ΣGmn. If the position and orientation of the center of the lower surface of the specified section Da is taken as the target value TP, then the three-dimensional position coordinates of that target value TP are the position vector in the reference coordinate system ΣGmn. G TP(X TP , Y TP , Z TP ) T This can be expressed by the following formula (1). Here, the height of container Ct is Hc, and the height of the j-th container Ct in the stacked tier (distance between the top and bottom surfaces) is ΣH cj Let the correction value be ΔH. If the tier number of the specified number is j, then the height is ΣH. cj This represents the height from the XY plane of the reference coordinate system ΣGmn to the top surface of (j-1) containers Ct, assuming there is no slope on the ground of the storage lane SL. The correction value ΔH is a value that corrects the Z coordinate of the target point TP to a value that can be considered as the height from the XY plane of the reference coordinate system ΣGmn to the center of the bottom surface of the actual designated section Da.

[0059]

number

[0060] Container Ct height H cThe correction value ΔH may be a fixed value, but it may also vary depending on the specifications of the container Ct (for example, normal type and high cube type). The correction value ΔH is a fixed value that has been pre-stored in the auxiliary storage unit 5c. The correction value ΔH may be a value that corrects the Z coordinate of the target value TP to be equivalent to the height of the center of the bottom surface of the actual designated section Da, but it is preferable to correct the Z coordinate to a height lower than that height. If the Z coordinate of the target value TP is equivalent to the center of the bottom surface of the actual designated section Da, there is a risk that the repetition of the position and orientation adjustment process S120 will stop just before the controlled object Ca lands on the designated section Da. Therefore, by correcting the Z coordinate of the target value TP to a height lower than the height of the center of the bottom surface of the actual designated section Da using the correction value ΔH, it becomes possible to reliably repeat the position and orientation adjustment process S120 until the controlled object Ca lands.

[0061] The correction value ΔH is equal to the height H of the container Ct. c It can be arbitrarily set within a smaller range than the specified value. The correction value ΔH is preferably between 300mm and 1000mm, and more preferably between 500mm and 700mm. Even if there is a slope on the ground (yard surface), the slope is at most about 1%, so the change in height of the center of the bottom surface of the designated section Da due to the slope is about ±250mm. Therefore, even at the maximum slope, by using the correction value ΔH, the Z coordinate of the target value TP will reliably point to a position lower than the center of the bottom surface of the designated section Da. The correction value ΔH may be a common value for multiple storage lanes SL, or different values ​​may be set for each combination number (mn). If multiple correction values ​​ΔH are set for a single container terminal, it is preferable that the correction values ​​ΔH for each combination number be accumulated in map data D1.

[0062] Figure 5 shows an example of the storage state of container Ct in section number (111). The thick solid rectangles in the figure represent the stored container Ct, and the thin dashed rectangles represent section D and designated section Da. The white dots are the centers O of the bottom surface of each section D. 1111 , O 1112 , O 1113The diagram shows the coordinate system, with the large black dot indicating the target value TP and the small black dot indicating the origin g11 of the reference coordinate system ΣG11. The bottom surface of each section D is the storage surface where the container Ct is actually stored, and represents the ground of the storage lane SL or the top surface of the stored container Ct. Therefore, the bottom surface of section D with designation number (1111) is the ground of the storage lane SL, and the bottom surface of section D with designation numbers (1112, 1113) is the top surface of the stored container Ct.

[0063] Sections D with the same part number (111) but different tier numbers are located at the center O of the bottom surface of each section D. 1111 , O 1112 , O 1113 These lie on the same vertical line L111. The vertical line L111 is a straight line parallel to the Z11 axis of the reference coordinate system ΣG11, regardless of the slope of the ground (yard surface) in the storage lane SL, and is centered at the bottom surface O of each section D. 1111 , O 1112 , O 1113 It is passing through.

[0064] If the management system specifies the number (1113), the three-dimensional position coordinates of the target value TP are (0, Y 111 , 2H c The result is -ΔH). In the diagram, the centers of the bottom surfaces of the two stored containers Ct are desirable to be on the vertical line L111, but in reality, due to control errors during landing, they may not be on line L111 but may be in a position shifted from line L111. Even if the centers of the bottom surfaces of the stored containers Ct are in a position shifted from line L111, the target value TP will not shift from line L111 and will always be on line L111.

[0065] When the controlled object Ca is the lifting device 13, it is desirable to align the center of the lower surface of the lifting device 13 with the center of the upper surface of the container Ct being handled. However, since the target value TP obtained in step S110 roughly indicates the position and orientation of the center of the lower surface of the designated area Da, a discrepancy occurs between the center of the upper surface of the container Ct and the target value TP when the ground is sloped. This discrepancy between the lifting device 13 and the container Ct being handled is resolved by using the flippers on the lifting device 13. The lifting device 13 is equipped with flippers at at least four corners as a device that physically guides the lifting device 13 directly above the container Ct being handled. For example, one end of the flipper is pivotally attached to the body of the lifting device 13, and by tilting around the pivotally attached end, the other end comes into contact with the side of the container Ct being handled. This operation of the flippers resolves the discrepancy between the lifting device 13 and the container Ct being handled.

[0066] In the position and orientation alignment process S120, by using map data D1, containers Ct can be automatically stacked vertically regardless of the slope of the ground in the storage lane SL relative to the horizontal plane. Generally, in order to stack containers Ct vertically, it is necessary to directly measure the slope of the ground in the storage lane SL relative to the horizontal plane, or to measure and acquire the slope as data in advance, but by using map data D1, this effort can be eliminated. Furthermore, by using map data D1, the effects of slope changes due to aging or crustal deformation are completely eliminated, and more accurate vertical stacking can be performed consistently.

[0067] Map data D1 only needs to be created during the preparation phase before the repetition of the position and orientation adjustment process S120. Map data D1 can be used repeatedly once it has been created, but it is advisable to correct it if the three-dimensional position coordinates of each section D change due to earthquakes, crustal movements, etc.

[0068] Next, we will describe the procedure for step S130 illustrated in Figure 2, that is, the embodiment of the method for acquiring the position and attitude of the crane controlled by the present invention. In the following, the control point c is defined as the point indicated by the three-dimensional position coordinates of the controlled quantity Cv, that is, the center of the lower surface of the controlled object Ca.

[0069] The procedure for acquiring position and orientation as illustrated in Figure 6 (the procedure in step S130) uses the reference coordinate system ΣGmn, the structural coordinate systems ΣLA and ΣLB, the trolley (movable part) coordinate system ΣT, and the suspension device coordinate system ΣS, as described in the map data D1 illustrated in Figure 3 above. The details of each coordinate system and each step (S131, S132) are described below.

[0070] Figure 7 shows the coordinate systems of the reference coordinate system ΣGmn, the structural coordinate systems ΣLA and ΣLB, the trolley coordinate system ΣT, and the suspension coordinate system ΣS, and their respective position vectors ( G la, G p, G t, G q, G s, G This represents c). In the diagram, thin arrows indicate the axes of each coordinate system, and thick arrows indicate the position vectors. The direction indicated by the arrow is considered positive, and the opposite direction is considered negative. The black dots indicate the origin gmn of the reference coordinate system ΣGmn, and the white dots indicate the origins, intersections, and control points c of coordinate systems other than the reference coordinate system ΣGmn.

[0071] The structural coordinate systems ΣLA, ΣLB, the trolley coordinate system ΣT, and the lifting device coordinate system ΣS are three-dimensional Cartesian coordinate systems in which the origins la, lb, t, and s are fixed to the structure 11, trolley 12, and lifting device 13, respectively, and the coordinate axes change with the position and orientation of the structure 11, trolley 12, and lifting device 13. Each origin represents the center of the lower surface of each part of the crane 10, which is treated as a rigid body. In the structure 11, the traveling devices 14 located below each end of the girder 18 in the direction of extension are treated as a pair of rigid bodies spaced apart in the direction of extension, and a separate coordinate system is set for each traveling device 14. In these coordinate systems, the position and orientation of each origin changes with the movement and change in orientation of the crane 10, relative to a fixed reference coordinate system ΣGmn.

[0072] The structural coordinate systems ΣLA and ΣLB are fixed to each of the pair of running gears 14 that are spaced apart in the Y direction. Since the structural coordinate systems ΣLA and ΣLB differ only in the positions of their origins la and lb and the orientation of their axes, only the details of structural coordinate system ΣLA will be described, and the details of structural coordinate system ΣLB will be omitted. The origin la is the center of the lower surface of the running gear 14, that is, the center of the running gear 14 on the ground of the storage lane SL, which is the contact surface of the tires of the running gear 14. LA The axial direction of the axis is not the vertical direction, but rather the direction in which the structure 11 is erected (for example, the direction in which the leg portion 19 extends). LA The axial direction of the axis indicates the extension direction of girder 18.

[0073] The trolley coordinate system ΣT is fixed relative to the trolley 12. The origin t is the center of the lower surface of the trolley 12, that is, the center of the trolley 12 in the horizontal plane of the girder 18 directly below the trolley 12 (the plane including the upper surface of the rail on which the wheels of the traverse device 15 roll). T The axial direction of the axis indicates the height direction of the trolley 12. T The axial direction of the axis is the direction of extension of the girder 18, which is the traverse direction of the trolley 12 (Y in the structural coordinate system ΣLA). LA This indicates the axis direction.

[0074] The lifting device coordinate system ΣS is fixed to the lifting device 13. The origin s is the center of the lower surface of the lifting device 13, that is, the center of the lifting device 13 at the contact surface with the container Ct (the lower end surface of the lifting device 13). S The axis direction of the shaft indicates the height direction of the suspension device 13. S The axial direction of the shaft is the longitudinal direction of the suspension device 13, Y S The axis directions indicate the short-side directions of the suspension device 13. Note that the Z coordinate system is ΣS. S The axis direction is not necessarily vertical. S The axial direction of the shaft may be tilted in directions other than the vertical due to the influence of the cable-like structure and vibration damping devices.

[0075] Z coordinate system of the structural coordinate system ΣLA LA Axis and the Y coordinate system ΣT T It intersects the axis. p is Z LA Axis and Y T This is the intersection of the axes. po is the traverse limit position of trolley 12. Structural coordinate system ΣLB and Z LB Axis and the Y coordinate system ΣT T It intersects the axis. r is Z LB Axis and Y T It is the intersection of the axes. q is the Z coordinate system of the suspension device coordinate system ΣS. S This is the intersection point between the shaft and the upper end surface of the lifting device 13. Depending on the specifications of the crane 10, the intersection point p and the traverse limit position po may coincide.

[0076] Structural data D2 is obtained during the preparation phase before cargo handling is performed by crane 10. Structural data D2 is data that complements the position and orientation data D3, which is illustrated in Figure 8 later, and is not essential if the control amount Cv can be calculated using only the position and orientation data D3. In other words, if the control amount Cv can be calculated using only the position and orientation data D3 obtained in step S131 later, the acquisition of structural data D2 in this preparation phase can be omitted.

[0077] The structural data D2 illustrated in Figure 8 is obtained during the preparation stage before cargo handling is performed by the crane 10 and is stored in the auxiliary storage unit 5c of the computing unit 5. This structural data D2 includes the height dimension of the structure 11, the width dimension of the structure 11, the thickness dimension of the lifting device 13, and the thickness dimension of the container Ct. More specifically, the height dimension of the structure 11 is the distance H between the origin la and the intersection point p. p The width dimension of structure 11 is the distance L between the origin la and the origin lb. ab The distance L between intersection point p and intersection point r pr The thickness dimension of the suspension device 13 is the distance H between the intersection point p and the origin s. s The thickness dimension of container Ct is the height H of container Ct. c The distance between the bottom and top surfaces is shown. Note that if the intersection point p and the traverse limit point po of the trolley 12 are different, the structural data D2 will show the distance Y between the intersection point p and the traverse limit point po of the trolley 12. to This is included. In the diagram, the numerical values ​​of each data are abbreviated with "...". Structural data D2 may use actual measured values, but it may also use design values ​​from the design stage of crane 10.

[0078] Structural data D2 can be used repeatedly if the specifications of crane 10 do not change, and can be applied to other cranes 10 with the same specifications. Therefore, once structural data D2 for cranes 10 with the same specifications has been obtained, obtaining structural data D2 in the preparation stage can be omitted as long as cranes 10 with the same specifications are used.

[0079] In step S131, position and orientation data D3 is acquired by the position and orientation acquisition devices (2a, 2b, 3, 4). The position and orientation data D3 includes multiple measurements of the position and orientation of the structure 11, the trolley 12, and the lifting device 13 in each of the following coordinate systems: the reference coordinate system ΣGmn, the structure coordinate system ΣLA, ΣLB, the trolley coordinate system ΣT, and the lifting device coordinate system ΣS. The position and orientation data D3 includes at least the measurements in the reference coordinate system ΣGmn, the structure coordinate system ΣLA, ΣLB, and the trolley coordinate system ΣT.

[0080] The position and orientation data D3 illustrated in FIG. 9 is acquired by the position and orientation acquisition devices (2a, 2b, 3, 4) and stored in the auxiliary storage unit 5c of the arithmetic unit 5. This position and orientation data D3 accumulates a plurality of measurement values acquired by the position and orientation acquisition devices (2a, 2b, 3, 4).

[0081] Specifically, the measurement values acquired by the structure position and orientation acquisition device 2a are the coordinates of the origin la of the structure coordinate system ΣLA in the reference coordinate system ΣGmn ( G la X , G la Y ) and the inclination ( G ξ LA , G η LA ). The measurement values acquired by the structure position and orientation acquisition device 2b are the coordinates of the origin lb of the structure coordinate system ΣLB in the reference coordinate system ΣGmn ( G lb X ) and the inclination ( G ξ LB , G η LB ). Note that the same Y coordinate as that of the origin la ( G la Y ) can be used for the Y coordinate of the origin lb. The measurement values acquired by the moving part position and orientation acquisition device 3 are the lateral travel distance of the trolley 12 in the trolley coordinate system ΣT T Y t and the inclination of the trolley 12 in the reference coordinate system ΣGmn ( G ξ T , G η T ). As illustrated in FIG. 7 described above, the structure coordinate system ΣLA and the trolley coordinate system ΣT intersect at the intersection point p, and the Y LA axis and the Y T axis are parallel. Therefore, the lateral travel distance of the trolley 12 in the trolley coordinate system ΣT T Y t can also be converted into the lateral travel distance of the trolley 12 in the structure coordinate system ΣLA. The lateral travel distance T Y t is from the lateral limit position po to Y TIt shows the distance that the trolley 12 travels horizontally in the axial direction. The measurement values acquired by the spreader position and orientation acquisition device 4 are the three-dimensional coordinates of the intersection point q in the trolley coordinate system ΣT ( T q X , T q Y , T q Z ) and the inclination of the spreader 13 in the reference coordinate system ΣGmn ( G ξ S , G η S ) and the skew angle of the spreader 13 in the trolley coordinate system ΣT T ζ S .

[0082] In step S132, data processing for calculating the position vector G c and the integrated skew angle G ζ c as the position and orientation of the control target Ca in the reference coordinate system ΣGmn is executed. In step S132 of the embodiment, data processing using a plurality of coordinate transformation matrices from each of the structure data D2, the position and orientation data D3, the structure coordinate systems ΣLA, ΣLB, the trolley coordinate system ΣT, and the spreader coordinate system ΣS to the reference coordinate system ΣGmn (see formula (2) described later) is executed. Note that in this step S132, depending on the position and orientation data D3, data processing using the position and orientation data D3 and a plurality of coordinate transformation matrices may be executed without using the structure data D2. The position vector G c is a vector from the origin g of the reference coordinate system ΣGmn to the control point c of the control target Ca. The integrated skew angle G ζ c is an angle obtained by integrating the skew angles (rotation angles around the Z axis) of each coordinate system (ΣLA, ΣLB, ΣT, ΣS) in the reference coordinate system ΣGmn.

[0083] Specifically, the position vector G c is the position vector from the origin gmn to the origin la of the structure coordinate system ΣLa, the intersection point p between the structure coordinate system and the trolley coordinate system ΣT, the origin t of the trolley coordinate system ΣT, the intersection point q between the trolley coordinate system ΣT and the spreader coordinate system ΣS, and the origin s of the spreader coordinate system ΣS ( G la, G p, Gt, G q, G Calculated based on s). Integrated skew angle G ζ S This is calculated by integrating the skew angles of each coordinate system.

[0084] The coordinate transformation matrices from each coordinate system (ΣLA, ΣLB, ΣT, ΣS) to the reference coordinate system ΣGmn are stored in the auxiliary storage unit 5c of the arithmetic unit 5. These coordinate transformation matrices can be expressed using the following known equation (2), and are expressed by substituting the angles of motion of each coordinate system as seen from the reference coordinate system ΣGmn into the respective rotation angles (ξ, η, ζ) in equation (2). The respective angles of motion of each coordinate system are the respective angles of motion of the structural coordinate system ΣLA ( G ξ LA , G η LA , G ζ LA ), the respective angles of motion of the structural coordinate system ΣLB ( G ξ LB , G η LB , G ζ LB ), the respective angles of motion of the trolley coordinate system ΣT ( G ξ T , G η T , G ζ T ), the respective angles of motion of the suspension coordinate system ΣS ( G ξ S , G η S , G ζ S ) . Each coordinate transformation matrix is ​​a coordinate transformation matrix from the structural coordinate system ΣLA to the reference coordinate system ΣGmn. G R LA , Coordinate transformation matrix from structural coordinate system ΣLB to reference coordinate system ΣGmn G R LB , coordinate transformation matrix from trolley coordinate system ΣT to reference coordinate system ΣGmn G R T , Coordinate transformation matrix from the suspension coordinate system ΣS to the reference coordinate system ΣGmn G R SThe skew angles of the structural coordinate systems ΣLA, ΣLB, trolley coordinate system ΣT, and suspension coordinate system ΣS are as follows: G ζ LA , G ζ LB , G ζ T , G ζ S ) is the integrated skew angle, which will be discussed later. G ζ S It is calculated during the calculation process.

[0085]

number

[0086] Position vector of origin la G la is the coordinate of the origin la of the structural coordinate system ΣLA in the reference coordinate system ΣGmn. G la X , G la Y ,0) T This is represented by the following. When the structure 11 is moved by the traveling device 14, the origin gmn is the target stopping position, and at the time the movement is completed (when the movement stops), the origin la and the origin gmn are close together. That is, the amount of displacement in the Z direction between the origin la and the origin gmn is small and can be considered to be zero.

[0087] Position vector of intersection point p G p is expressed by the following formula (3): Position vector LA p is the coordinate of the intersection point p using the structural coordinate system ΣLA (0, 0, H p ) T This indicates that.

[0088]

number

[0089] Position vector of the origin t G t is expressed by the following formula (4): Position vector Tp is the coordinate of the intersection point p in the trolley coordinate system ΣT (0, -( T Y t + T Y to ), 0) T This indicates that.

[0090]

number

[0091] Position vector of intersection point q G q is expressed by the following formula (5): Position vector T q is the coordinate of the intersection point q in the trolley coordinate system ΣT. T q X , T q Y , T q Z ) T This indicates that.

[0092]

number

[0093] Position vector of origin s G s is expressed by the following formula (6): Position vector S q is the coordinate of the intersection point q in the suspension coordinate system ΣS (0, 0, H q ) T This shows that when the origin s is treated as the control point c (when the controlled object Ca is only the suspension device 13), the position vector G s is used as the position vector of the control point c.

[0094]

number

[0095] Position vector of control point c G c is expressed by the following formula (7): Position vector Sc is Z in the ΣT coordinate system of the suspension device. S The coordinates of control point c, which is the intersection of the axis and the lower end face of container Ct, are (0, 0, -H c ) T This indicates that.

[0096]

number

[0097] Skew angle of structure 11 G ζ LA and skew angle G ζ LB Although these can be treated individually, we consider structure 11 as a single rigid body and treat them as having the same value. Skew angle G ζ LA This is expressed by the following formula (8). Skew angle of this structure 11 G ζ LA This is used in the above-mentioned formula (2).

[0098]

number

[0099] Skew angle of trolley 12 G ζ T This is the skew angle of digit 18. G ζ GDR This can be considered as such. Skew angle of digit 18 G ζ GDR This is the skew angle of structure 11. G ζ LA This reflects the distortion of leg section 19. Skew angle of beam 18 G ζ GDR This is expressed by the following formula (9): X-coordinate of intersection point p G p X This is expressed by the above formula (3). The x-coordinate of the intersection point r G r X This is the position vector represented by the following formula (10). G The position vector of the origin lb can be obtained from r. Glb is the coordinate of the origin lb of the structural coordinate system ΣLB in the reference coordinate system ΣGmn. G lb X , G la Y ,0) T It is represented by the position vector. LB r is the coordinate of the intersection point r using the structural coordinate system ΣLB (0, 0, H p ) T This indicates that.

[0100]

number

[0101]

number

[0102] Integrated skew angle G ζ S That is, the skew angle of the suspension coordinate system ΣS G ζ S This is the skew angle of the lifting device 13 in the trolley coordinate system ΣT, acquired by the lifting device position and orientation acquisition device 4. T ζ S The skew angle of trolley 12 in the trolley coordinate system ΣT was calculated as follows: G ζ T It is the sum of and , and is expressed by the following formula (11). Therefore, the integrated skew angle G ζ S The skew angles of the structure 11, the trolley 12, and the suspension device 13 are integrated.

[0103]

number

[0104] As described above, according to this embodiment, by utilizing the position and orientation data D3 that is acquired sequentially during the loading and unloading of the crane 10, the control quantity Cv (position vector) is used as the position and orientation of the controlled object Ca in the reference coordinate system ΣGmn. G c, integrated skew angle G ζ c ) can be acquired sequentially. In other words, in this embodiment, it is not necessary to directly measure the position and orientation of the designated area Da. Therefore, in the process of cargo handling by the crane 10, the position and orientation of the controlled object Ca in the reference coordinate system ΣGmn can be acquired at an earlier stage than when it becomes possible to directly measure the relative position between the trolley 12 or lifting device 13 and the designated area Da, and the position and orientation adjustment with the designated area Da can be started earlier using the acquired position and orientation.

[0105] Furthermore, in the crane 10, the position and orientation of each part of the structure 11, trolley 12, and lifting device 13 change dynamically moment by moment due to disturbances such as uneven loads and wind while the trolley 12 and lifting device 13 are in operation. According to this embodiment, these dynamic changes can be captured by sequentially acquiring the position and orientation of the controlled object Ca in the reference coordinate system ΣGmn.

[0106] By installing a radio wave positioning device such as a satellite positioning system antenna (GNSS) on the suspension device 13, the control quantity Cv can be directly acquired using the World Geodetic System. However, with radio wave positioning devices, the control quantity Cv may not be acquired depending on the radio wave conditions. Therefore, the target value TP is acquired using a local three-dimensional Cartesian coordinate system, the reference coordinate system ΣGmn, and the position vector is obtained using that reference coordinate system ΣGmn as the control quantity Cv. G c and integrated skew angle G ζ S By identifying this, the position and orientation adjustment process S120 can be performed regardless of radio wave conditions.

[0107] Next, we will describe in detail the procedure for creating each operating command based on the variation of the controlled variable Cv, assuming that the controlled variable Cv matches the target value TP, as illustrated in step S140 in Figure 2 above.

[0108] In this procedure, the data processing for calculating the variation amount of the vector that can be operated and the integrated skew angle among the vectors constituting the position vector G c when it is assumed that the control amount Cv matches the target value TP is executed by the arithmetic processing unit 5a. Hereinafter, the control amount Cv when it is assumed that it matches the target value TP is defined as the target position vector G ζ S is executed. Hereinafter, the control amount Cv when it is assumed that it matches the target value TP is defined as the target position vector G c * and the target skew angle G ζ S * . The target position vector G c * matches the three-dimensional position coordinates G TP of the target value TP. Similarly, the target skew angle G ζ S * also matches the skew angle G ζ TP of the target value TP.

[0109] The position vector G c is represented by the following formula (12) using the above formulas (3) to (7). Among the position vectors G c, the vectors that can be operated by the operation of the trolley 12 and the spreader 13 are the position vector T p of the intersection point p in the trolley coordinate system ΣT and the position vector T q of the intersection point q. That is, the target position vector G c * is represented by the following formula (13) with those operable vectors as the variation vectors T p * and the variation vector T q * .

[0110]

Equation

[0111]

Equation

[0112] Assuming that the controlled variable Cv matches the target value TP, the target position vector G c * and the position vector of the target value TP G TP becomes equal to this. The following equation (14) is the target position vector of the above equation (13). G c * position vector G This is a modified version with TP replaced.

[0113]

number

[0114] Variation vector T p * This shows the coordinates of intersection point p in the trolley coordinate system ΣT. The coordinates of intersection point p are such that the X and Z coordinates are fixed values, and the Y coordinate is expressed as the traverse distance of trolley 12 from the traverse limit point po and a fixed value. Specifically, the variation vector T p * However, the target coordinates (0, -( T Y t * + T Y to ), 0) T This indicates the amount of variation. T Y t * This is the traverse distance of the trolley 12 from the traverse limit position po, assuming that the controlled variable Cv matches the target value TP.

[0115] Variation vector T q * This shows the coordinates of the intersection point q in the trolley coordinate system ΣT. The coordinates of the intersection point q are such that the Y coordinate is the observed value (see position and orientation data D3 in Figure 9), the X coordinate is the amount of movement of the suspension device 13 in the X direction, and the Z coordinate is the amount of movement of the suspension device 13 in the Z direction. Specifically, the fluctuation vector T q * is the target coordinates ( Tq X * , T q Y , T q Z * ) T This indicates the amount of variation. T q X * This is the amount of movement of the suspension device 13 in the X direction, assuming that the controlled variable Cv matches the target value TP. Also, the fluctuation amount T q Z * This is the amount of descent of the suspension device 13 in the Z direction, assuming that the controlled variable Cv matches the target value TP.

[0116] The right-hand term of the above formula (14) can be quantified from the map data D1, structural data D2, and position and orientation data D3. Therefore, each variation can be calculated using the above formula (14). T Y t * , T q X * , T q Z * It can be quantified.

[0117] Integrated skew angle G ζ S Among these, the angle that can be operated by the operation of the trolley 12 and the suspension device 13 is the skew angle. T ζ C That is the skew angle. T ζ C This is the skew angle of the controlled object Ca in the trolley coordinate system ΣT, and is expressed by the following equation (15) using the above equation (11). Therefore, the target skew angle G ζ C * The amount of variation is the fluctuating skew angle. T ζ S * This can be expressed by the following formula (16).

[0118]

number

[0119] [Number] ···(16)

[0120] When it is assumed that the control amount Cv matches the target value TP, the target skew angle G ζ S * and the skew angle G ζ TP of the target value TP become equal. The following formula (17) is obtained by replacing the target skew angle G ζ S * with the skew angle G ζ TP of the target value TP and transforming the above formula (16). The variation amount T ζ S * indicates the rotation angle of the skew of the spreader 13 by the fine movement device 17 when it is assumed that the control amount Cv matches the target value TP.

[0121] [Number] ···(17)

[0122] The right side of the above formula (17) can be quantified from the map data D1, the structure data D2, and the position and orientation data D3. Therefore, the variation amount T ζ S * can be quantified.

[0123] Next, a method and system for acquiring the position and orientation of the object controlled by the crane, as well as a modified example 1 of the crane's embodiment, will be described. Modified example 1 is suitable when the Z coordinate of the target value TP indicates a position lower than the height of the center of the actual lower surface of the designated area Da due to the correction value ΔH. In modified example 1, the relative position acquisition device 6 is used to acquire the vertical relative position of the object controlled Ca and the container Ct located directly below the designated area Da. That is, in the control method of the crane 10 using the position and orientation acquisition system 1A of modified example 1, the repetition of the position and orientation adjustment process S120 is terminated just before the object controlled Ca lands on the designated area Da, so that the object controlled Ca lands on the designated area Da in a way that further reduces the impact that occurs when it lands.

[0124] In the modified example 1 shown in Figure 10, a relative position acquisition device 6 is installed on the suspension device 13. The position and orientation acquisition system 1A in modified example 1 differs from the position and orientation acquisition system 1 in Figure 1 above only in the addition of a relative position acquisition device 6, so the overall configuration is not shown. In the illustrated example, an example of part number (111) is shown, similar to Figure 4 above.

[0125] The relative position acquisition device 6 can use known distance meters such as two-dimensional or three-dimensional laser sensors or stereo cameras. The relative position acquisition device 6 acquires the shape of the top surface of container Ct located directly below the designated area Da and the distance to that top surface and the ground (yard surface). The relative position acquisition device 6 may also be installed on the trolley 12.

[0126] Figure 11 shows an example of the procedure for controlling a crane using the position and orientation acquisition system 1A in Modified Example 1. In this control method, steps S170 to S200 are added between the position and orientation adjustment process S120 and step S160 compared to the procedure in Figure 2 described above. The added step S170 corresponds to the process added in Modified Example 1. That is, in the procedure of this control method, the repetition of the position and orientation adjustment process S120 ends just before the controlled object Ca lands in the designated area Da (S170, S180). Just before the controlled object Ca lands in the designated area Da, the controlled amount Cv is roughly in line with the target value TP, except for the difference in the Z direction. Therefore, after the repetition of the position and orientation adjustment process S120 ends, only the amount of movement in the Z direction is generated as an operation command for the lifting device 13 (S190), and the lifting device 13 is operated based on the generated operation command to land the controlled object Ca in the designated area Da (S200). The details of each step (S170-S200) are described below.

[0127] In step S170, the relative position acquisition device 6 is used to determine the vertical distance H from the control point c, which is the center of the lower surface of the controlled object Ca, to the upper surface of the container Ct located directly below the designated section Da. O Obtain the distance H. O Distance H0 is selected from the measurements obtained by the relative position acquisition device 6 as the maximum vertical distance to the top surface of container Ct located directly below the designated area Da. If there is no container Ct directly below the designated area Da, distance H0 is selected as the maximum vertical distance to the bottom surface (ground) of the designated area Da. If the bottom surface of the designated area Da is not inclined with respect to the horizontal plane, distance H O This indicates the distance from control point c to the center of the lower surface of the designated area Da. If the lower surface of the designated area Da is inclined with respect to the horizontal plane, the distance H OThis represents the vertical distance from control point c to a point on the lower surface of the designated area Da that is lower than the center of the lower surface. A point lower than the center of the lower surface means the edge of the lower surface of the designated area Da or the vicinity of that edge. Specifically, based on the measurement value measured by the relative position acquisition device 6, the calculation processing unit 5a identifies the point on the upper surface of container Ct located directly below the designated area Da that is furthest from the center downwards, and the vertical distance from control point c to that identified point is distance H. O The data processing to obtain the data is then performed.

[0128] In step S180, the calculation processing unit 5a performs data processing to determine whether the controlled object Ca is about to implant in the designated section Da. Indicators for determining whether it is about to implant include the difference in the Z direction between the controlled quantity Cv and the target value TP, and the distance H obtained using the relative position acquisition device 6. O This can be used. The criteria for determining whether implantation is imminent can be set arbitrarily. If it is determined in step S180 that implantation is imminent (S180: YES), the position and orientation adjustment process S120 is terminated. If it is determined that implantation is not imminent (S180: NO), the position and orientation adjustment process S120 is repeated again.

[0129] In step S190, the correction value ΔH and the distance H obtained using the relative position acquisition device 6 are used. O Based on this, the calculation processing unit 5a performs data processing to create the amount of movement of the lifting device 13 in the Z direction as an operation command for the lifting device 13. The center of the lower surface of the designated section Da lies between the target point TP and a point located above the target point TP by a correction value ΔH in the Z direction. Furthermore, its center lies between the control point c and a distance H from the control point c. O It exists between the point located below by a certain distance. Based on these two conditions, the calculation processing unit 5a searches for the amount of downward movement of the suspension device 13 in the Z direction. The amount of movement to be searched may be a value that makes the Z coordinate of control point c exactly match the Z coordinate of the center of the lower surface of the designated section Da, or it may be a value that moves the Z coordinate of control point c above the Z coordinate of the target point TP and below the Z coordinate of the center of the lower surface of the designated section Da.

[0130] In step S200, the calculation processing unit 5a performs data processing to operate the lifting device 13 based on the created operation command. Specifically, the calculation unit 5 transmits the created operation command to the lifting device 16, causing the lifting device 16 to lower the lifting device 13 in the Z direction.

[0131] As described above, in Modification 1, just before the controlled object Ca lands in the designated area Da, the relative position acquisition device 6 acquires the relative position between the controlled object Ca and the lower surface of the designated area Da. Then, based on the acquired relative position, the controlled object Ca lands in the designated area Da. Specifically, just before landing, the repetition of the position and orientation adjustment process S120 is completed, and the correction value ΔH and the distance H acquired using the relative position acquisition device 6 are acquired. O The suspension device 13 is lowered by the amount of movement determined based on the calculation. Since the amount of movement determined is a value that moves the control point c closer to the center of the lower surface of the designated section Da, the impact that occurs when the controlled object Ca lands on the designated section Da can be further mitigated.

[0132] In Modification 1, since the relative position acquisition device 6 acquires the relative position between the controlled object Ca and the lower surface of the designated area Da, the three-dimensional position coordinates of the target value TP in the position and orientation adjustment process S120 can also be changed based on the relative position. This method is suitable when the controlled object Ca is only the lifting device 13. In detail, when the controlled object Ca is only the lifting device 13, from the time the relative position acquisition device 6 becomes able to acquire the relative position in step S170 until the position and orientation adjustment process S120 is completed in step S180, the calculation processing unit 5a performs data processing to acquire the three-dimensional position coordinates of the center of the upper surface of the container Ct located directly below the designated area Da based on the measurement values ​​measured by the relative position acquisition device 6. Next, the calculation processing unit 5a performs data processing to change the three-dimensional position coordinates of the target value TP to the three-dimensional position coordinates of the center of the upper surface of the container Ct from which the three-dimensional position coordinates were acquired. Then, by repeating the position and orientation adjustment process S120 using the three-dimensional position coordinates of the center of the top surface of the container Ct, it becomes possible to adjust the position and orientation of the center of the bottom surface of the lifting device 13 to the center of the top surface of the container Ct located directly below the designated area Da. Thus, in this modified example 1, by using the relative position acquisition device 6, it is also possible to adjust the position and orientation of the center of the bottom surface of the lifting device 13 to the center of the top surface of the container Ct to be handled.

[0133] Next, a method and system for acquiring the position and attitude of a crane-controlled object, as well as a modified example 2 of the crane's embodiment, will be described. In modified example 2, a filtered value obtained by removing the effects of dynamic disturbances from the measured values ​​of some of the position and attitude data D3 is used instead of the measured values, thereby enabling the position and attitude of the controlled object Ca to be determined with higher accuracy.

[0134] As illustrated in Figure 12, the position and attitude acquisition system 1B of Modified Example 2 has a notch filter 7 added to the configuration of the position and attitude acquisition system 1 in Figure 1 described above. The notch filter 7 is interposed between the position and attitude acquisition devices (2a, 2b, 3, 4) and the arithmetic unit 5. That is, in Modified Example 2, at least some of the measured values ​​of the position and attitude data D3 are replaced with filtered values ​​obtained by applying the notch filter 7.

[0135] A known notch filter is used for the notch filter 7. The notch filter 7 may be applied to all measurements acquired by the position and attitude acquisition devices (2a, 2b, 3, 4), but it is sufficient to apply it only to measurements that become statically indeterminate due to the influence of dynamic disturbances. The measurements to which the notch filter 7 is applied should be appropriately selected according to the dynamic disturbances.

[0136] Dynamic disturbances include, for example, acceleration during the traverse of the trolley 12 and wind. Acceleration during the traverse of the trolley 12 causes periodic swings in the suspension device 13, affecting the Y coordinate of point q in the trolley coordinate system ΣT. T q Y This becomes an indeterminate value. In addition, periodic fluctuations occur in the pitch direction in the structure 11 that receives the reaction force of the trolley 12, and the rotation angle of the pitch in the structural coordinate systems ΣLA and LB. G ξ LA , G ξ LB This also becomes an indeterminate value. The wind causes vibration in the structure 11, and the rotation angle of the roll in the structure coordinate system ΣLA, LB G η LA , G η LB This becomes an indeterminate value. Therefore, the notch filter 7 is the Y coordinate of point q. T q Y , rotation angle of the pitch of the structural coordinate system ΣLA,LB G ξ LA , G ξ LB , roll direction angle G η LA , G η LB It is set to act on each of the measured values. Multiple notch filters 7 may be set up to adapt to each dynamic disturbance, and the setting parameters may be variable.

[0137] The notch filter 7, for example, when its order is second, can be expressed by the following formula (18). The notch filter 7 has the notch center frequency ω as a setting parameter. n , Notch width (bandwidth) ζ n , Notch depth (center frequency ω n (Attenuation amount at) d nIt has.

[0138]

number

[0139] The setting parameters can be arbitrarily set within a range where the filter value is quasi-statically determinate or can be considered statically determinate. However, the depth d within the setting parameters is limited. n If the value exceeds "1.0", the notch filter 6 becomes an amplified filter, so it should be kept below "1.0". The center frequency ωn is, for example, the natural frequency of the deflection or vibration that affects the measured value being applied. This natural frequency can be determined in advance by analyzing the vast amount of data accumulated by the crane 10 manufacturer over the years, or by analyzing laboratory data such as the results of numerous experiments, tests, and computer simulations conducted during the research and development of the crane 10. Alternatively, this natural frequency may be calculated using the dynamic model described in Modification 3 below. Notch width ζ n This involves the Q-factor (quality factor Q) and the center frequency ω n It is calculated using [the specified formula]. The depth dn can be set appropriately according to the amplitude of the runout or vibration.

[0140] The fluctuations and vibrations that affect the measured values ​​decrease as the controlled object Ca approaches the designated area Da. Therefore, it is preferable that the notch filter 7 is gradually released as the fluctuations in the measured values ​​decrease. Specifically, as the controlled object Ca approaches the designated area Da, the depth d of the set parameter n The value gradually increases and is set to approximate "1.0". The notch filter 7 is completely released when the controlled Cac is about to implant in the designated compartment Da.

[0141] As described above, according to Example 2 of the change, the filter value obtained by applying the notch filter 7 has the effect of dynamic disturbances largely eliminated from the measured value and can be considered a statically determinate value. Therefore, the control variable Cv (position vector) obtained using the position and attitude data D3 including that filter value is... G c, integrated skew angle G ζc This largely eliminates the effects of dynamic disturbances. As a result, the position and orientation of the controlled object Ca can be determined more accurately, which is advantageous for performing position and orientation adjustments with higher precision.

[0142] Next, a method and system for acquiring the position and orientation of a crane-controlled object, as well as a modified example 3 of the crane's embodiment, will be described. In modified example 3, instead of some of the measured values ​​of the position and orientation data D3, estimated values ​​obtained by removing the effects of dynamic disturbances from those measured values ​​are used, thereby obtaining the position and orientation of the controlled object Ca with higher accuracy. The position and orientation acquisition system 1C in modified example 3 calculates estimated values ​​by processing the measured values ​​using a dynamic model 8 that is pre-stored in the auxiliary storage unit 5c.

[0143] The block diagram illustrated in Figure 13 shows the dynamic model 8 under disturbance. Examples of disturbances include vibrations caused by the traverse of the trolley 12, vibrations caused by wind, vibrations caused by the movement of the running gear 14, and swings of the suspension device 13 due to the traverse of the trolley 12. The dynamic model 8 is a model of a one-degree-of-freedom vibration system where the mechanical equilibrium point and the geometric equilibrium point (geometric center) are different. The dynamic model 8 is, for example, a model of a spring-mass damper system supported by two springs with different natural lengths. Estimated values ​​are calculated using the equation of state of the dynamic model 8. Various known estimation methods can be used to estimate the values ​​using the dynamic model 8, such as methods using disturbance observers, methods using Kalman filter state estimation algorithms, and methods using successive least squares methods.

[0144] In the illustrated example, the dynamic model 8 has a disturbance observer 9. The disturbance observer 9 calculates the deviation between the mechanical equilibrium point and the geometric equilibrium point in the dynamic model 8 as x Δ Let the deviation xΔ be the disturbance. Disturbance observer 9 detects the incoming disturbance (deviation x Δ This state estimator estimates all state variables, including ), and can use a known same-dimensional disturbance observer. Details of disturbance observer 9 will be described later.

[0145] Figure 14 shows an example of the procedure for acquiring the position and attitude of the crane's controlled object in Modification 3. In Modification 3, another step S133 is added to the procedure in Figure 6 described above. That is, in the procedure of Modification 3, an estimated value is calculated using the dynamic model 8 due to disturbances for the measured values ​​acquired by the position and attitude acquisition devices (2a, 2b, 3, 4) (S133). Therefore, in each step of the subsequent position and attitude adjustment process S120 (S140, S150), at least some of the measured values ​​in the position and attitude data D3 are replaced with the calculated estimated values.

[0146] More specifically, in step S133, the arithmetic processing unit 5a performs data processing to calculate estimated values ​​for some of the measured values ​​of the position and attitude data D3 using the dynamic model 8 due to disturbances. Specifically, the disturbance observer 9 calculates the estimated values. In this step, first, the equations of motion are created using the dynamic model 8 (equations of state) which models the vibration and oscillation due to disturbances, and each parameter of the dynamic model 8 is calculated using the created equations of motion. Next, the dynamic model 8 is considered as a model of a one-degree-of-freedom vibration system where the mechanical equilibrium point and the geometric equilibrium point (geometric center) are different, and the estimated values ​​are estimated using the equations of state of that model.

[0147] As an example of the procedure for calculating each parameter of the dynamic model 8, we will explain the procedure for the vibration of the structure 11 of the crane 10 due to the traverse of the trolley 12 using the modal method. The finite element equation of state for the vibration of the structure 11 due to the traverse of the trolley 12 is expressed by the following equation (19). In the following equation (19), the relative displacement vector of the structure 11 from the ground is x r Let M, C, and K be the matrices for mass, damping, and stiffness, respectively, and let f be the reaction force that the structure 11 receives when the trolley 12 is driven. t Let the elements corresponding to the nodes of structure 11 on which the trolley reaction force acts be 1, and the vectors of all the others be 0, be V. t do.

[0148]

number

[0149] Eigenvalue analysis using the above formula (19) shows that the vibrational characteristics (natural frequencies, natural modes) of crane 10 are expressed by the following formula (20). In the following formula (20), let q be the mode coordinate vector and Φ be the mode matrix, and from left to right Φ T It is putting that into action.

[0150]

number

[0151] Due to the orthogonality of the natural modes, the matrices M, C, and K for mass, damping, and stiffness in equation (20) above can be diagonalized. By extracting only the vibration modes that affect a given measurement value from equation (20) above and converting from the modal coordinate system to the physical coordinate system, the equation of motion that describes the vibration of the given measurement value is expressed by the following equation (21). In the following equation (21), the natural angular frequency is ω i Let the damping ratio be σ i The excitation coefficient from the ground is ψ ig Let ψ be the coefficient that shows the contribution of the reaction force from the trolley 12 to the mode acceleration. iT The mode value corresponding to the position of the position and attitude acquisition device (any of 21 to 23) that acquires predetermined measurement values ​​is φ is Let's assume that.

[0152]

number

[0153] The equation of motion shown in equation (21) above represents the vibration of the measurement point due to the traverse of the trolley 12. Similarly, vibrations due to movement by the running device 14 and wind disturbances can also be modeled and equations of motion can be created. Each parameter (ω) in equation (21) above i , σ i ψ ig ψ iT, φ is These parameters can be determined from the results of known finite element method analyses. Alternatively, each parameter can be identified and determined from measurements obtained by position and attitude acquisition devices (2a, 2b, 3, 4) during the actual operation of the crane 10, or it can be determined using both the results of finite element method analyses and the identification of the measured values.

[0154] As an example of the procedure for calculating each parameter of the dynamic model 8, the procedure for the swing of the suspension device 13 due to the traverse of the trolley 12 will be explained. The vibration of the suspension device 13 due to the traverse of the trolley 12 can be represented by an equation of motion that approximates a simple pendulum with small swing, and this equation of motion is expressed by the following equation (22). In the following equation (22), the displacement of the trolley 12 is x T Let x be the displacement of the pendulum (suspension device 13) as seen from the trolley 12. S Let the natural angular frequency of the pendulum be ω S Let ζ be the natural damping ratio of the pendulum. S Let's assume that.

[0155]

number

[0156] Each parameter (ω) in the above formula (22) S ζ S ) can also be identified and determined from measurements obtained by position and attitude acquisition devices (2a, 2b, 3, 4) during the actual operation of the crane 10.

[0157] As an example of the procedure for estimating the estimated value, we will explain the procedure for the swing of the suspension device 13 due to the traverse movement of the trolley 12. The equation of motion when the swing of the suspension device 13 due to the traverse movement of the trolley 12 is considered as vibration of the spring-mass damper system is expressed by the following equation (23). Its state equation is expressed by the following equation (24), and the observation equation is expressed by the following equation (25). In the following equations (23), (24), and (25), the deviation between the mechanical equilibrium point and the geometric equilibrium point is x. Δ Let's assume that.

[0158]

number

[0159]

number

[0160]

number

[0161] The deviation x in the above formula (24) Δ Considering this as a disturbance, the estimated value is calculated using the disturbance observer 9 exemplified in Figure 13 above. In disturbance observer 9, the matrices that model the object are A, b, and C, and the matrix of the nominal model is A en , b en , C en , C en2 Let the gain matrix be L0. The disturbance observer 9 will be an online operation, but the gain matrix L0 cannot be designed online, so it is designed offline beforehand. Specifically, the gain matrix L0 is designed using the pole configuration (A en -L0C en The eigenvalues ​​of the model are designed to be arbitrary poles.

[0162] The disturbance observer 9, which uses the gain matrix L0 designed offline by pole configuration, is expressed by the following equation (26).

[0163]

number

[0164] Figure 15 shows an example of the simulation results of estimated values ​​using the disturbance observer 9. The displacement of the suspension device 13 from the start to the end of the trolley 12's traverse motion was simulated as an estimated value. In the example shown, the horizontal axis shows the time elapsed from the start to the end of the trolley 12's traverse motion, and the vertical axis shows the displacement of the suspension device 13, the acceleration of the trolley 12, and the change in the estimated value. The dashed line shows the change in acceleration during the trolley 12's traverse motion. The dashed line shows the actual displacement of the suspension device 13. The three solid lines show the estimated values ​​obtained using the procedure of step S133 described above, and are the results of changing the desired pole configuration in three different ways.

[0165] The actual displacement of the suspension device 13, shown by the dashed line, follows the change in acceleration due to the traverse of the trolley 12, shown by the dashed line. After the displacement changes significantly due to the change in acceleration, it settles to a statically determinate value (0.05 [m]). The estimated value shown by the three solid lines asymptotically approaches the statically determinate value (0.05 [m]) at a stage before the dashed line reaches the statically determinate value. Therefore, it can be seen that the estimated value estimated in step S133 can estimate the statically determinate value earlier.

[0166] In variation 3, the Y coordinate of point q in the trolley coordinate system ΣT is T q Y The estimated value x was calculated by disturbance observer 9. Δ (The correct term is ^x Δ ) is used. Similarly, the rotation angle of the pitch of the structural coordinate systems ΣLA and LB. G ξ LA , G ξ LB , roll direction angle G η LA , G η LB The estimated value obtained using the state equation based on the above formula (21) is used.

[0167] As described above, according to Modification 3, for some measured values ​​that become statically indeterminate due to dynamic disturbances, estimated values ​​obtained using a dynamic model due to disturbances are used. As shown in Figure 15 above, these estimated values ​​asymptotically approach statically indeterminate values ​​early on. Therefore, the control variable Cv (position vector) obtained using the estimated values ​​instead of the measured values ​​of the position and attitude data D3 is used. G c, integrated skew angle G ζ c This approach largely eliminates the effects of dynamic disturbances. This allows for a more accurate understanding of the position and orientation of the controlled object Ca, which is advantageous for performing position and orientation alignment with higher precision.

[0168] Next, a method and system for acquiring the position and orientation of the crane's controlled object, as well as a modified example 4 of the crane's embodiment, will be described. Modified example 4 has the same configuration as the position and orientation acquisition system 1 illustrated in Figure 1 above. In the position and orientation acquisition method of modified example 4, measured data D4a and D4b based on the position and orientation of the controlled object Ca at the time it was landed are stored in the auxiliary storage unit 5c of the arithmetic unit 5. That is, when the controlled object Ca is to be landed again in a designated area Da where it has landed at least once, the measured values ​​of the measured data D4a and D4b are used instead of at least some of the measured values ​​in the map data D1 and position and orientation data D3.

[0169] Figure 16 shows an example of the procedure for acquiring the position and orientation of the crane's controlled object in Modification 4. In the procedure of Modification 4, step S130 is added after the controlled object Ca has been grounded (S160:YES) compared to the control method procedure in Figure 2 described above, and another step S210 is added. That is, in the procedure of Modification 4, the actual value data D4a and D4b are updated based on the acquired control amount Cv (S210). Therefore, in the next position and orientation adjustment process S120, the updated actual value data D4a and D4b are used.

[0170] In step S210, the calculation processing unit 5a performs data processing to update the actual value data D4a and D4b based on the control quantity Cv when the controlled object Ca lands in the designated section Da. In step S210, the two-dimensional position coordinates and skew angles for each sub-number that the map data D1 originally possesses are maintained without being changed.

[0171] The actual data D4a shown in Figure 17 is updated several times as the controlled object Ca has landed in several designated areas Da. The actual data D1a is created based on map data D1, with the Z coordinate added as an actual value. This Z coordinate is the position and orientation (position vector) of the controlled object Ca acquired at the time of landing. G c) is based on the following: That is, the actual value data D4a is the three-dimensional position coordinate ((0,Y) for each specified number (1111~mnij). 111 ,Z 1111 ), , , (0, Y 111 It has ,-) and ····). For designation numbers where the controlled Ca has not implanted, it is represented by "-" because the Z coordinate of the three-dimensional position coordinate is not specified.

[0172] In the section D of the specified number (1111) in the actual data D4a, the controlled object Ca has implanted at least once, and the three-dimensional position coordinate Z coordinate (Z 1111 ) is added as an actual value. Therefore, if section D with designated number (1111) is designated as designated section Da in position and orientation adjustment process S120, by using this actual value data D4a instead of map data D1, the three-dimensional position coordinates described in the actual value data D4a will be used as the target value TP. In this way, when actual value data D4a is used instead of map data D1, the Z coordinate added as an actual value is the position vector acquired when the controlled object Ca lands. G It is preferable to use the value obtained by subtracting the correction value ΔH from the Z coordinate of c.

[0173] The actual value data D4b exemplified in Figure 18 is updated several times as the controlled object Ca has been grounded in several designated areas Da. The measured value data D4b contains actual values ​​for each designated number (1111~mnij). The actual values ​​can be arbitrarily selected from the measured values ​​of the position and orientation data D3 exemplified in Figure 9 above, but it is preferable to select measured values ​​that are greatly influenced by the characteristics of the ground on which the crane 10 is grounded. The actual values ​​include, for example, the pitch direction angle of the structural coordinate system ΣLA, LB. G ξ LA , G ξ LB , angle in the roll direction G η LA , G η LB , angle in the pitch direction of the trolley coordinate system ΣT G ξ T , angle in the roll direction G η T That is the case.

[0174] In the section D of the specified number (1111) in the actual data D4b, the controlled object Ca has landed at least once, and the angle in the pitch direction of the structural coordinate system ΣLA, LB G ξ LA , G ξ LB , angle in the roll direction G η LA , G η LB , angle in the pitch direction of the trolley coordinate system ΣT G ξ T , angle in the roll direction G η T The following has been added. Therefore, if section D with designated number (1111) is designated as section Da in the position and orientation adjustment process S120, the actual measured value of the actual value data D4b is used instead of the measured value of the position and orientation data D3 for data processing of the controlled variable Cv and the operation command value. The actual value data D4b may be added to the map data D1, or it may be stored as data separate from the map data D1.

[0175] As described above, according to Modification 4, the actual value data D4a is updated each time the controlled object Ca lands in the designated area Da. The Z coordinate added or changed by this update approximates the center of the bottom surface of area D more accurately than the Z coordinate calculated based on the tier number of the designated number. Therefore, in subsequent position and orientation adjustment processes S120, using the updated actual value data D4a is advantageous for more accurately determining the three-dimensional position coordinate of the center of the bottom surface of the designated area Da. This enables more accurate position and orientation adjustment between the controlled object Ca and the designated area Da.

[0176] The actual data D4a can be updated each time the controlled object Ca lands in the designated section Da, but the update may be restricted to when the controlled object Ca is a container Ct lifted by the lifting device 13, and not updated when the controlled object Ca is the lifting device 13. Section D virtually represents a container Ct stored in the target position and orientation. Therefore, restricting the update of the actual data D1a, and updating the actual data D4a only when the controlled object Ca is a container Ct, is advantageous for improving the accuracy of position and orientation alignment.

[0177] Furthermore, the actual values ​​added to the actual value data D4b faithfully represent the position and orientation of each part of the crane 10 structure 11, trolley 12, and lifting device 13 when the controlled object Ca lands in the designated area Da, and the effects of dynamic disturbances are eliminated. Therefore, in subsequent position and orientation adjustment processes S120 for the same designated area D, by using the added actual values ​​instead of the measured values ​​in the position and orientation data D3, the values ​​obtained by excluding the fluctuations in the creation of the operation command become fixed values. Thus, by repeating the position and orientation adjustment process S120 using the actual value data D4b, the effects of dynamic disturbances are corrected (eliminated). As a result, if interference is included in the characteristics of the repeated position and orientation adjustment process S120, it can be compensated with good responsiveness, which is advantageous for higher-precision position and orientation adjustment.

[0178] The above variations 1 to 4 can be selected as appropriate. Furthermore, for example, variations 1 can be combined with any of variations 2 to 4. Also, variations 2 to 4 can be combined as appropriate, dividing the period from the start of operation of the trolley 12 to implantation into sections.

[0179] Although embodiments of the present invention have been described above, the method and system for acquiring the position and orientation of a crane's controlled object, as well as the crane itself, are not limited to specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0180] The crane 10 described above is not limited to the configuration of the embodiment. For example, the crane 10 can be a known overhead crane in which the structure 11 does not have legs 19. Alternatively, the crane 10 can be a known gantry crane in which the girder 18 of the structure 11 extends to one side in the Y direction. The movable part of the crane 10 is not limited to the trolley 12. The movable part can be any part whose position and orientation relative to the structure 11 changes as a result of its operation. The movable part can be, for example, a boom that rotates with a slewing device or a boom that extends and retracts with a telescopic device, and the crane 10 can also be a known jib crane or a mobile crane (truck crane, railway crane).

[0181] In the example control method described above, the traverse device 15 controls the traverse of the trolley 12 in the Y direction, the lifting device 16 controls the lifting of the suspension device 13 in the Z direction, and the fine adjustment device 17 controls the movement of the suspension device 13 in the X direction and skew around the vertical line. However, the configuration is not limited to this. For example, instead of the fine adjustment device 17, the traveling device 14 may move the structure 11 in the X direction to control the movement of the suspension device 13 in the X direction. Similarly, instead of the fine adjustment device 17, the traveling device 14 may skew the structure 11 around the vertical line to control the skew of the suspension device 13 around the vertical line. In addition, the fine adjustment device 17 may be used in conjunction with the traverse device 15 to control the fine movement of the suspension device 13 in the Y direction. The degrees of freedom of the controlled object Ca are not limited to four degrees of freedom, but may be five or six degrees of freedom, and the lifting device 16 and the fine adjustment device 17 may trim or list the suspension device 13. In other words, in the position and orientation adjustment process S120, the trim angle and wrist angle may be adjusted as orientation. When a common moving device is used for the trolley 12 and the lifting device 13, which integrate the traversing device 15 and the lifting device 16, the moving device may be configured to perform traversal in the Y direction of the trolley 12, lifting in the Z direction of the lifting device 13 and skew around the vertical line, while the fine adjustment device 17 performs movement of the lifting device 13 in the X direction. [Explanation of Symbols]

[0182] 1, 1A, 1B, 1C Position and Attitude Acquisition System 2a, 2b, 3, 4 Position and orientation acquisition device 5 Computing device 5a Arithmetic Processing Unit 5b Main memory 5c Auxiliary storage section (storage section) 6. Relative position acquisition device 7 Notch Filter 8. Dynamic Models 9. Disturbance Observer 10 Cranes 11 Structures 12 Trolley (movable part) 13 Hanging equipment D1 Map Data D2 Structural Data D3 Position and Orientation Data D4a, D4b Actual Value Data TP target value Cv control variable ΣGmn reference coordinate system ΣLA, ΣLB Structural Coordinate System ΣT Trolley coordinate system (movable part coordinate system) ΣS Lifting device coordinate system

Claims

1. In a method for acquiring the position and orientation of a crane's controlled object during cargo handling using a crane comprising a structure having a traveling mechanism, a movable part that operates in contact with the structure, and a lifting device that operates suspended from the movable part via a cable-like material, the method involves acquiring the position and orientation of the lifting device or the load lifted by the lifting device as the controlled object, The reference coordinate system is a three-dimensional orthogonal coordinate system in which the origin is fixed on the ground where the cargo is stored and one of the coordinate axes is the vertical line. The three-dimensional orthogonal coordinate systems in which the origins of the structure, the movable part, and the lifting device are fixed to the structure, the movable part, and the lifting device respectively, and whose coordinate axes change according to the position and orientation of the structure, the movable part, and the lifting device, are designated as the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system. During cargo handling by the crane, position and orientation data is sequentially acquired by at least three or more position and orientation acquisition devices installed on the structure, the movable part, and the lifting device, which collect multiple measurements in the respective coordinate systems of the reference coordinate system, the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system, respectively, as the position and orientation of the structure, the position and orientation of the movable part, and the position and orientation of the lifting device. A method for acquiring the position and orientation of a crane's controlled object, wherein, each time the position and orientation data is acquired, a computing device performs data processing using a plurality of coordinate transformation matrices from the structural coordinate system, the movable part coordinate system, and the lifting device coordinate system to the reference coordinate system, and the position and orientation data, thereby acquiring the position and orientation of the controlled object in the reference coordinate system.

2. The method for acquiring the position and orientation of a crane-controlled object according to claim 1, wherein in the handling of the crane, the controlled object is grounded in a designated area where the position and orientation in a predetermined coordinate system is specified, and the predetermined coordinate system is used as the reference coordinate system.

3. Prior to the loading and unloading operation by the crane, structural data including at least the height dimension of the structure, the width dimension of the structure, and the thickness dimension of the lifting device should be known in advance. The method for acquiring the position and orientation of a crane's controlled object according to claim 1, wherein the data processing uses the plurality of coordinate transformation matrices, the position and orientation data, and the structural data.

4. The method for acquiring the position and orientation of a crane's controlled object according to claim 1, wherein the data processing involves calculating a position vector from the origin of the reference coordinate system to the origin of the structure coordinate system, from the origin of the reference coordinate system to the intersection of the structure coordinate system and the movable part coordinate system, from the origin of the reference coordinate system to the origin of the movable part coordinate system, from the origin of the reference coordinate system to the intersection of the movable part coordinate system and the lifting device coordinate system, and from the origin of the reference coordinate system to the origin of the lifting device coordinate system, based on the respective position vectors, and also by integrating the skew angles of the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system in the reference coordinate system to calculate an integrated skew angle, and acquiring the position vector from the origin of the reference coordinate system to the controlled object and the integrated skew angle as the position and orientation of the controlled object in the reference coordinate system.

5. In a crane control object position and orientation acquisition system that acquires the position and orientation of a control object, during cargo handling by a crane comprising a structure having a traveling device, a movable part that operates in contact with the structure, and a lifting device that operates suspended from the movable part via a cable-like material, the system controls the lifting device or the load lifted by the lifting device as the control object, and acquires the position and orientation of the control object. The reference coordinate system is a three-dimensional orthogonal coordinate system in which the origin is fixed on the ground where the cargo is stored and one of the coordinate axes is the vertical line. The three-dimensional orthogonal coordinate systems in which the origins of the structure, the movable part, and the lifting device are fixed to the structure, the movable part, and the lifting device respectively, and whose coordinate axes change according to the position and orientation of the structure, the movable part, and the lifting device, are designated as the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system. The structure, the movable part, and the suspension device are each installed on the structure, the movable part, and the suspension device, and each of these devices sequentially acquires position and orientation data in which multiple measurements are accumulated in the respective coordinate systems of the reference coordinate system, the structure coordinate system, the movable part coordinate system, and the suspension device coordinate system, respectively, as the position and orientation of the structure, the position and orientation of the movable part, and the position and orientation of the suspension device, and the calculation device has a storage unit that stores multiple coordinate transformation matrices from each of the structure coordinate system, the movable part coordinate system, and the suspension device coordinate system to the reference coordinate system, and a calculation processing unit, A crane control target position and attitude acquisition system configured such that each time the position and attitude data is acquired, the calculation processing unit performs data processing to acquire the position and attitude of the control target in the reference coordinate system based on the plurality of coordinate transformation matrices and the position and attitude data.

6. The crane's cargo handling system is configured such that the controlled object is grounded in a designated area where its position and orientation in a predetermined coordinate system is specified, and the reference coordinate system is the same as the predetermined coordinate system, as described in claim 5.

7. The storage unit has pre-stored structural data including at least the height dimension of the structure, the width dimension of the structure, and the thickness dimension of the lifting device. The crane control target position and orientation acquisition system according to claim 5, wherein the data processing uses the plurality of coordinate transformation matrices, the position and orientation data, and the structural data.

8. In the data processing described above, a position vector from the origin of the reference coordinate system to the controlled object is calculated based on the position vectors from the origin of the reference coordinate system to the origin of the structure coordinate system, from the origin of the reference coordinate system to the intersection of the structure coordinate system and the movable part coordinate system, from the origin of the reference coordinate system to the origin of the movable part coordinate system, from the origin of the reference coordinate system to the intersection of the movable part coordinate system and the lifting device coordinate system, and from the origin of the reference coordinate system to the origin of the lifting device coordinate system. At the same time, an integrated skew angle is calculated by integrating the skew angles of the structure coordinate system, the movable part coordinate system, and the lifting device coordinate system in the reference coordinate system, and the position vector from the origin of the reference coordinate system to the controlled object and the integrated skew angle are obtained as the position and orientation of the controlled object in the reference coordinate system, as described in claim 5.

9. A notch filter that acts on at least a portion of the measured values ​​in the position and orientation data is stored in the storage unit, The crane control target position and attitude acquisition system according to claim 5, wherein in the data processing, the filtered values ​​obtained by the notch filter are used instead of the measured values ​​for at least some of the position and attitude data.

10. The crane control target position and attitude acquisition system according to claim 5, wherein in the data processing, an estimated value is calculated by applying a dynamic model due to disturbances to at least some of the measured values ​​in the position and attitude data, and the estimated value calculated by applying the dynamic model is used instead of the measured values ​​in at least some of the position and attitude data.

11. The actual measured data based on the position and orientation data at the time when the controlled object has landed and the cargo handling by the crane has been completed is stored in the storage unit. The crane control target position and attitude acquisition system according to claim 5, wherein, when the control target is to be placed again at a location where the control target has been placed at least once, the data processing uses the actual measured values ​​of the actual measured value data instead of at least some of the measured values ​​in the position and attitude data.

12. A crane equipped with a position and attitude acquisition system for a crane's controlled object as described in any one of claims 5 to 11.

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