JP7386476B2 - Steady rest control system for hoisting conveyor equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a system for controlling the steadying of a suspended load in a hoisting and conveying device that lifts a suspended load from a predetermined loading location and transports it to a prescribed location. The present invention relates to a control system used for hoisting and conveyance when the suspended load is lifted from the ground (the lifting of the suspended load from the surface of the place where it is placed).

2. Description of the Related Art When a suspended load is transported by a transport device such as a crane, the suspended load swings during transportation, so a mechanism has been proposed to prevent the suspended load from swinging. This type of technology is equipped with a slide base that can slide on a trolley, an actuator that reciprocates the slide base with minute strokes in the direction of swing of the suspended load, and a hoisting device (winch) is installed on the slide base. A conveyance device with this configuration has been developed (see Patent Document 1). This technology calculates the natural period when a suspended load swings from the length of the suspended load, and then uses an actuator to linearly reciprocate the slide base at a period greater than the natural period, thereby reducing the swing. It was something to do.

However, when lifting a suspended load from a predetermined placement location and moving it to a predetermined location, in addition to the swinging of the suspended load during transportation, there is also vibration associated with ground cutting. Therefore, in order to suppress the shake caused by the ground break, a technology has been developed that reduces the shake caused by the ground break by moving the trolley directly above the suspended load and then winding up the hoisting rope (Patent Document 2). reference). In addition, in order to reduce the initial swing due to the ground cutting, the hoisting rope is made taut before the ground cutting starts, and the swing angle of the hoisting rope or the length of the hoisting rope is adjusted. A technology has also been developed that detects and moves the trolley in a direction where these detected values become smaller (see Patent Document 3).

Japanese Patent Application Publication No. 2004-277143 JP2002-362880A JP 2019-119583 Publication

The techniques disclosed in Patent Documents 2 and 3 mentioned above are both aimed at reducing the initial swing of a suspended load due to ground cutting, and by moving the trolley or boom, the techniques disclosed in Patent Documents 2 and 3 are designed to reduce the lifting of the suspended load at the time of ground cutting. It guided the direction vertically. In other words, the trolley is moved forward and backward before the ground cutting starts, and after the ground cutting, it is sufficient to suppress the vibration caused by normal conveyance.

However, when the trolley or boom is moved before the start of ground cutting and the hoisting rope is controlled to be in the vertical direction, an event occurs in which the trolley or boom is moved forward or backward relative to the transport direction. Therefore, it takes time to control the position of the trolley or boom before the ground cutting starts, and prompt transportation to the destination position is hindered. Further, even if the initial runout caused by the ground breaking is suppressed, some runout will still occur during the conveyance, so it is necessary to suppress the runout even after the ground breaking.

Further, none of the above-mentioned patent documents take into consideration changes in the posture of the suspended load. That is, it is based on the assumption that when the sling rope is slung onto a hook or the like, the sling position is in the vertical direction of the center of gravity of the suspended load. However, it is not easy to sling the slinging rope directly above the center of gravity of the suspended load, and if the slinging position is offset from the center of gravity, when the suspended load is lifted (i.e., just before it comes off the ground), , the suspended load would be tilted. Due to the inclination of the suspended load, the shake (initial shake) that occurs when the load breaks off the ground can be different from the shake that occurs during transportation, but the above-mentioned patent document does not take into account the suppression of such shake. There wasn't.

The present invention has been made in view of the above-mentioned points, and its purpose is to take into account the occurrence of initial swing due to changes in the attitude of the suspended load during ground cutting, and to It is an object of the present invention to provide a steady rest control system capable of attenuating both vibration and vibration caused by conveyance after cutting off the ground.

Therefore, the inventors of the present invention have determined that, in conveyance work accompanied by a ground breaking phenomenon, by understanding the changes in the posture of the suspended load during the breaking, the initial runout due to the ground breaking and the runout due to the conveyance after the ground breaking can be reduced. It was discovered that the conveyance speed could be improved by comprehensively attenuating, and this led to the completion of the present invention.

That is, the present invention provides a hoisting means for hoisting a hoisting rope to lift a suspended load, a moving means for moving the hoisted load together with the hoisting means, and a first means for providing a driving force to the moving means. a second drive means for providing a driving force to the hoisting means; a rope angle detection means for detecting an angle in the axial direction of the hoisting rope; and a control means for controlling both drive states of the drive means, in the hoisting and conveying device for hoisting a suspended load to a predetermined height and transporting it to a target position, the control means is configured to control the drive state of the first drive means. On the other hand, a transport control section that controls the movement of the moving means from the start of driving until reaching the target position, and a lift control section that controls lifting of the suspended load to a predetermined height for the second driving means. an upper control section; and a determination section that determines the state of the suspended load based on the axial angle and angular velocity of the hoisting rope detected by the rope angle detection means; The present invention is characterized in that the transport speed is controlled so as to guide the axial angle of the hoisting rope in the vertical direction while referring to the determined state of the suspended load.

According to the above configuration, the rope angle detection means detects the angle in the axial direction of the hoisting rope, and the detected angle can detect (or calculate) the angle that occurs between the hoisting rope and the vertical direction, The condition of the suspended load can be determined by changing the angle. In other words, if the hoisting rope is under tension and there is already an angle between the vertical direction and the hoisting rope, the position of the lower end of the hoisting rope (the upper end of the slinging rope) will change when the trolley, etc. It can be determined that it is not directly under the means. Furthermore, by hoisting the hoisting rope, the suspended load is pulled in the axial direction of the hoisting rope, but at this time, the suspended load may be cut off immediately after being pulled, or It is also possible to slide the suspended load along the surface of the location or to tilt the suspended load. Furthermore, the suspended load may be tilted and slid. If the suspended load slides or tilts during the ground cutting, the angle between the hoisting rope and the vertical direction will change to become smaller, but the angle between the hoisting rope and the vertical direction will change, but the angle between the hoisting rope and the vertical direction will change continuously and in both forward and reverse directions, such as swinging after the ground cutting. It does not cause any change in

Therefore, during the ground cutting, the angle of the hoisting rope changes gradually. Further, when the hoisting load is lifted by hoisting the hoisting rope, the hoisting load is grounded and swings. A state in which a suspended load swings is a state in which an event occurs in which the angle of the hoisting rope exceeds the vertical state and is angled in the opposite direction. Therefore, when the swinging state of the suspended load is detected, the acceleration of the moving means is changed by moving the moving means such as a trolley in the direction of the target position while controlling the speed of the movement, thereby reducing the swinging of the hanging load. It is something that can be attenuated. Through such control, it is possible to simultaneously stop the initial runout due to ground cutting and the runout due to conveyance. By starting the steady rest control after the ground cutting, it is possible to omit the position control of the moving means according to the angle of the hoisting rope during the ground cutting, and the entire runout including the initial runout is treated as the conveyance runout. It can be stopped. In addition, even if you control the position of the transportation means before (including during) the ground cutting, by setting the time from the start of the ground cutting operation to the ground cutting in a short time, it will be easier to prevent the ground cutting from occurring. It is possible to reduce the initial runout due to ground cutting while shortening the previous control time, and to quickly realize steady rest when damping together with conveyance runout.

Feedforward control and feedback control are possible methods for controlling the steady rest, but at least the control after breaking the ground is based on feedback control, and the angle and angular velocity of the hoisting rope detected by the rope angle detection means are input. value, and the moving means is accelerated in a state where the inclination angle increases in the same direction as the moving direction of the trolley, etc. In addition, when simply controlling the movement of the moving means so that the angle of the hoisting rope becomes smaller, the moving means may not only move forward but also move backward (move in forward and backward directions), and the control policy In this case, the conveyance speed can be improved by giving priority to the forward direction. In addition, even if feedback control is used before (including during) the ground cutting, if the hoisting rope continues to be hoisted up, the ground cutting will be completed in a short time, so the means of transportation during the ground cutting will be The control time for advancing and retreating can be short.

In the invention having the above configuration, the state of the suspended load is that it is being cut off the ground or after it has been cut off the ground. In addition to being able to calculate based on the angle and length of the upper rope, it can also be determined by inputting the condition of the suspended load as an image. If the above-mentioned control is started after the vehicle has cut off the ground, steady rest control can be performed without reversing the conveyance means. In addition, even if the control is performed during the ground cutting, the steady rest control can be performed without significantly affecting the conveyance speed of the moving means after the ground cutting due to the short ground cutting.

According to the present invention, in addition to reducing the occurrence of initial runout due to ground cutting during ground cutting, it is also possible to attenuate the conveyance runout that accompanies the initial runout. In addition, since it is possible to grasp the change in the attitude of the suspended load during the ground cutting, it is also possible to start steady rest control after the ground cutting, and the initial swing due to the ground cutting is attenuated together with the transport swing. be able to. Since the steady rest control after the ground crossing is performed by controlling the moving state of the moving means, it is possible to stabilize the moving means while moving it to the target position. Therefore, the travel time to the target position can be shortened.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram schematically showing an embodiment of the present invention. It is an explanatory view showing the change of the aspect of hanging load in ground cutting. It is an explanatory view showing the state of a suspended load during ground cutting. It is an explanatory view showing the state of the suspended load after breaking the ground. It is an explanatory view showing the state of a suspended load at ground cutting. It is an explanatory view showing the state of a suspended load during ground cutting. It is an explanatory view showing the state of the suspended load after breaking the ground. It is an explanatory view showing the state of a suspended load during ground cutting. It is an explanatory view showing the state of a hanging load in steady rest control. It is an explanatory view showing the state of a hanging load in steady rest control. 3 is a graph showing the results of Experiment 1. 3 is a graph showing a comparative example with Experiment 1. 3 is a graph showing the results of Experiment 1. 3 is a graph showing a comparative example with Experiment 1.

<Device overview>
Embodiments of the present invention will be described below based on the drawings. FIG. 1 is a schematic diagram showing an example of an embodiment of the present invention. As shown in FIG. 1, this embodiment is a control system for a trolley-type hoisting and conveying device. This hoisting and conveying device includes a trolley (moving means) 1 that moves linearly along a predetermined rail L, and a motor (first driving means) 2 that provides the driving force necessary for moving the trolley 1. It is equipped with Further, the trolley 1 is equipped with a winch 3 and a drive motor (second drive means) 4, and is capable of hoisting a hoisting rope 5 suspended from the trolley 1 (winch 3).

In order to transport the suspended load M, the hoisting rope 5 is wound up by the winch 3 to levitate the suspended load M, and the trolley 1 is moved to the desired position. To move the trolley 1, it is necessary to accelerate initially and finally decelerate and stop at the target position. Therefore, during acceleration and deceleration, vibration occurs when transporting the suspended load. is requested to stop. At the same time, it is also required to prevent the swinging caused by ground cutting (which refers to lifting the suspended load M and levitating the suspended load M from the surface N of the loading place. The same applies hereinafter).

In this embodiment, a laser sensor (rope angle detection means) 7 is installed in the trolley 1 to detect the angle in the axial direction of the hoisting rope 5 (the angle formed between it and the vertical direction). If the angle detected by this laser sensor 7 coincides with the vertical direction, it can be determined that the suspended load M exists directly below the trolley 1, and therefore, when steadying the load, the angle should be The trolley 1 is accelerated and decelerated in the traveling direction so as to match the vertical direction.

Further, in order to control the movement (speed/acceleration) of the trolley 1, the motor 2 is a servo motor, and an encoder provided on the servo motor can feed back the state of the driving force (motor speed). Note that the driving means is not limited to the servo motor, and other driving means may be used as long as the speed can be controlled. Further, the sensing of the driving state does not need to be an encoder. For example, it may be possible to analyze the position, speed, acceleration, etc. of the trolley 1 by processing images obtained through a photographing means.

Furthermore, in order to control the hoisting state of the hoisting rope 5, the motor 4 that drives the winch 3 is also a servo motor, and the drive state (hoisting speed) of the winch 3 can be fed back by an encoder provided on this servo motor. It is. Note that, similarly to the above, the driving means is not limited to the servo motor, but other driving means can be used as long as the speed can be controlled, and the sensing of the driving state does not need to be an encoder. .

Note that there may be various forms of the mechanism for moving the trolley 1, but in this embodiment, for convenience of explanation, a mechanism installed on the opposite side to the drive pulley 21 driven by the motor (first drive means) 2 is used. In this example, a driven pulley 22 is provided, a toothed belt 23 is suspended between the two pulleys 21 and 22, and a trolley is fixed to a part of the toothed belt 23. However, the trolley 1 in the transport device is not limited to the illustrated mechanism, and may be self-propelled, or a boom-type crane may be used as long as it is to be moved linearly. Further, an inertial measurement unit (IMU) may be installed on the suspended load M to detect the angle, angular velocity, acceleration, etc. of the suspended load M. In this case, as will be described later, the attitude of the suspended load M can be determined based on the measurement results.

As described above, the encoder information and the laser sensor 7 information (and the IMU 8 information) of both motors 2 and 4 are processed by the control device (control means) 9, and a control signal is output to both motors 2 and 4. I take it as a thing. This control device 9 has a configuration including a processing section 91 and a servo driver 92. Each detection information is input to the processing section 91, and in order to drive both motors 2 and 4 in a desired state, the servo driver 92 outputs control signals (voltage values) for the respective servo motors 2 and 4. Control signals from the servo driver 92 are output to the trolley motor 2 and winch motor 4 individually. Although the figure shows a single servo driver 92 for convenience of explanation, it may be controlled by individual servo drivers.

In this way, the processing section 91 and the servo driver 92 form individual control sections (transfer control section and lifting control section) for controlling the respective motors 2 and 4. The processing unit 91 also includes a determining unit that receives input of angle information of the hoisting rope 5 detected by the laser sensor (rope angle detecting means) 7 and determines the state of the suspended load M. Note that the configuration includes an interface (input/output unit) for inputting and outputting data as described above.

By the way, in this embodiment, the initial swing that occurs due to ground cutting is stopped, but it is assumed that this initial swing is due to a mismatch between the center of gravity G of the suspended load M and the direction in which it is hoisted by the hoisting rope 5. be done. That is, for example, if the hoisting rope 5 is aligned in the vertical direction and the center of gravity G of the hanging load M is located on the extension line, initial swing will not occur when the hoisting rope 5 breaks the ground by hoisting. When the hoisting rope 5 is inclined, or when the center of gravity G of the hanging load M does not exist on the extension line of the hoisting rope 5, the hoisting force (pulling force) when hoisting with the hoisting rope 5 is: This will act as a couple on the suspended load M. The action of this couple destabilizes the attitude of the suspended load M, resulting in initial swinging due to ground breaking.

Such destabilization of the posture of the suspended load M varies depending on, for example, the relationship between the bottom surface of the suspended load M shown in FIG. 1 and the surface N of the loading place. Assuming that the front end in the transport direction is the front end (right side in the figure) C, and the rear end in the transport direction is the rear end D (left side in the figure), one of the ends C and D is There may be a situation where one is floating and the other is on the ground. In this case as well, it is possible that one side may slide while being in contact with the ground. Furthermore, it may slide with both ends C and D in contact with the ground (that is, the entire bottom surface is installed). Even if the hoisting rope 5 hanging from the trolley 1 is vertical from the beginning, such an unstable state can occur if the center of gravity G is deviated.

<Changes in the appearance of suspended loads>
Therefore, the state of the suspended load M when applying the pulling force by the hoisting rope 5 can be classified into the following eight modes. This can be illustrated as a transition mode as shown in FIG. Note that "Swing" in the figure indicates a floating state, but it means that the suspended load M is in a swinging state. Further, "slide" means a sliding state, and "stick" means a stopped state. "C" is the state where only the front end C of the above (in Figure 1) is in contact with the ground, "D" is the state where only the rear end D of the above (in Figure 1) is in contact with the ground, and "Planar" is the state where the entire bottom surface is in contact with the ground. (Both ends C and D) are in a state of being in contact with the ground.

As shown in FIG. 2, the suspended load M subjected to a tensile force by the hoisting rope 5 passes through one of the modes and finally becomes a floating state "Swing". As a pre-stage to floating, there can be either a sliding state "slide" or a stopped state "stick". In both the sliding state "slide" and the stopped state "stick", there are modes in which the entire bottom surface "Planar" slides (slide) and modes in which it stops (stick). In addition, when one of the ends C and D floats and the other touches the ground, there are two modes: a "slide" mode and a "stick" mode when only the front end C is in contact with the ground. , even when only the rear end D is in contact with the ground, there is a mode in which the device slides, and a mode in which it stops and “sticks”.

Therefore, since the sliding state "slide" and the stopped state "stick" can occur in three types of grounding states, a total of six modes occur, and the "swing" mode of floating (swinging) after the sliding mode "slide" If we distinguish between the "swing" mode, which floats (swings) after stopping "stick", there can be a total of eight modes.

These eight aspects can be determined by detecting the tension of the hoisting rope 5, its reaction force and angle, the inclination angle and angular velocity of the suspended load M, and the frictional resistance with the surface N of the loading place. It is possible to understand this through calculation, but here we will only explain that it emerges via one of the modes.

<Position of suspended load>
As mentioned above, the state in which the suspended load M floats through the "slide" and stop "stick" states will be explained using a specific suspended load M. FIGS. 3 and 4 show state changes when transporting an L-shaped hanging load M. In the figure, the hanging load M is a heavy three-dimensional object with an appropriate thickness (thickness in the direction perpendicular to the plane of the figure), and its center of gravity G is located on the rear side of the center of the hanging load M when viewed from the front. shall be located at . Further, as shown in FIG. 1, sling ropes 6 are installed at two locations in front and rear of the suspended load M in the transport direction, and the sling rope 6 is attached to one location of the tip 51 of the hoisting rope 5. Although they are connected, the connection position is assumed to be fixed. Generally, the sling rope 6 is hung by a hook provided at the tip of the hoisting rope 5. Furthermore, the hoisting rope 5 is assumed to have flexibility. The hoisting rope 5 is configured to be wound around the winch 3, but for convenience of explanation, it is shown extending from the center of the trolley 1.

Therefore, first, when the hoisting rope 5 is appropriately hoisted, the hoisting rope 5 having flexibility is brought into a sufficiently tensioned state. This state is the initial state (see FIG. 3(a)). In addition, in this initial state, for convenience of explanation, the hoisting rope 5 is purposely set at a predetermined angle θ ₁ with respect to the vertical direction, and the center of gravity G of the suspended load M is on the rear side of the center of the suspended load M. (to the left in the figure).

From the above initial state, only the hoisting rope 5 is operated (driven by the motor 4) and the trolley 1 is stopped. It is assumed that the hoisting rope 5 starts hoisting at a predetermined acceleration and then hoists at a constant speed. However, the speed and acceleration of these windings shall not be large. By starting to wind up the hoisting rope 5, a tensile force will act on the suspended load M, and the suspended load M will be drawn in the axial direction of the hoisting rope 5. At this time, if the angle θ ₁ of the hoisting rope 5 is large, the entire bottom surface of the suspended load M will slide (planar slide) while being installed on the surface N of the loading place (Fig. 3 (b) reference). Thereafter, the planar sliding state ends as the angle θ ₁ of the hoisting rope 5 becomes smaller. Note that if the angle θ ₁ of the hoisting rope 5 in the initial state is small, planar sliding due to the entire bottom surface of the hanging load M may not occur. Furthermore, when the trolley 1 is made movable in the forward and backward directions (in a controlled state to be described later), the trolley 1 moves so as to reduce the angle θ ₁ of the hoisting rope 5. Planar sliding due to the entire bottom surface of the load M may not occur.

If the above-mentioned planar slide by the entire bottom surface of the suspended load M does not occur, or after that, the lighter side of the front end C or the rear end D of the suspended load M (front end C in the figure) rises, and only the other end (rear end D in the figure) is in contact with the surface N of the mounting place (see FIG. 3(c)). The reason why one end (front end C) rises and the suspended load M tilts is when the center of gravity of the suspended load M is not located on the extension line on which the tensile force of the hoisting rope 5 acts. This is how it appears.

Since the state in which the rear end D touches the ground occurs continuously from the planar slide caused by the entire bottom surface, the state in which the rear end D touches the ground may result in a slide caused only by the rear end D (D-slide). This is the case if the slide continues. Another aspect is that after sliding (planar slide) with the entire bottom surface in contact with the surface N of the mounting location, it temporarily stops (planar stick), and then only the front end C rises. . In this case, the vehicle is stopped (D-stick) with only the rear end D in contact with the ground (see FIG. 3(c)). In the initial state, if the angle θ ₁ of the hoisting rope 5 is smaller than the initial value, a sliding state (planar slide) by the entire bottom surface of the hanging load M does not appear, and the rear end D Only the ground can be a sliding (D-slide) or a stationary (D-stick) mode.

Note that since the hoisting operation on the hoisting rope 5 continues, the tensile force of the hoisting rope 5 acts on the suspended load M as a sideways force rather than as an upward force. If the force is superior and the frictional resistance becomes small with the front end C floating and only the rear end D touching the ground, the system will temporarily stop (D-stick) and then slide further (D-slide). ).

When the rear end D is in contact with the ground and slides (D-slide) or stops without sliding (D-stick), the hoisting rope 5 is continuously wound up. Eventually, the rear end D will also be in a floating state (see FIG. 4(a)). This state is a grounded state.

Immediately after breaking the ground, as shown in FIG. 4(a), the center of gravity G of the suspended load M is located on the extension line of the hoisting rope 5 in the axial direction, or is approximately on the extension line. It is assumed that the location will be the same. This is because the pulling force by the hoisting rope 5 acts toward the center of gravity G of the suspended load M, so there is a planar slide by the entire bottom surface of the suspended load M, or a sliding movement by only the rear end D. This is because the attitude of the suspended load M changes in this way during the D-slide.

However, for example, if the coefficient of friction between the suspended load M and the surface N of the loading place is extremely small, the center of gravity G of the suspended load M will be shifted from the hoisting rope 5 due to the inertial force caused by the sliding of the suspended load M. It may move further forward than on the extension line (see Fig. 4(b)). On the contrary to the above, when the frictional resistance is large, the center of gravity G may be delayed from the extension line of the hoisting rope 5 (see FIG. 4(c)). However, since the hoisting rope 5 is flexible and the suspended load M is heavy, the center of gravity G of the suspended load M will be located on the extension line of the hoisting rope 5 at an early stage after breaking the ground. It is assumed that this will be the case.

On the other hand, when the center of gravity of the suspended load M is located in the front, a different aspect occurs. For example, as shown in Fig. 5, when transporting an L-shaped suspended load M similar to the above, if the direction is reversed, the center of gravity G will be lower than the center of the suspended load M. is also in the initial state located on the front side (see FIG. 5(a)). In such a case, for example, if only the rear end D is floated without sliding and the front end C is in contact with the ground (C-slide), or without sliding. It is also conceivable that the vehicle may be stopped (C-stick). Even in such a case, the angle θ ₁ of the hoisting rope 5 becomes smaller as the posture (inclination) of the suspended load M changes (see FIG. 5(b)). After that, by continuing to wind up the hoisting rope 5, the entire body floats up while maintaining that state, or after the front end C slightly slides (C-slide) and stops again (C-stick). (see FIG. 5(c)).

On the other hand, FIGS. 6 and 7 show a state in which a long rod-shaped hanging load M is transported. It is assumed that the suspended loads M have the same thickness and the center of gravity is located at the center in the longitudinal direction. When transporting such a rod-shaped suspended load M, as shown in these figures, the tip of the hoisting rope 5 is directly connected to the front end C of the suspended load M without using a sling rope. It may be raised. In this case as well, although the above-mentioned eight aspects are possible, the state in which the hanging load M slides or stops (planar stick) by the entire bottom surface is considered to be omitted. Then, by winding up the hoisting rope 5 connected to the front end C, only the front end C rises, and only the other rear end D is in contact with the surface N of the mounting place, causing sliding (D-slide). ) (see FIGS. 6(b) and (c)). The distance traveled by this sliding (D-slide) can be relatively long, and it continues until the axis of the rod-shaped suspended load M is in an upright state to the same extent as the axis of the hoisting rope 5. It is assumed that (see FIG. 7(a)). Thereafter, as the hoisting rope 5 continues to be hoisted up, the rear end D also rises, and the whole is grounded (see FIG. 7(b)).

Further, the ground cutting condition described above is the same in jib cranes as well. FIG. 8 shows the ground cutting state when using the jib crane 10. As shown in this figure, a hoisting rope 5 is suspended from the tip of an arm 11 of a jib crane 10, and is connected to a sling rope 6 at the lower end of the hoisting rope 5. The arm 11 extends from the main body at the top of the mast and can change its angle in the upright direction and in the tilting direction, and is equipped with a winch 3 on the main body to wind up the hoisting rope 5. It is something that can be done. Therefore, when moving the suspended load M, the arm 11 can be raised up, and the winch 3 can be operated at the same time. Since it is possible to raise the hoisting rope 5 and move the suspended load M in the horizontal direction only by raising the arm 11, the driving of the arm 11 can be regarded as a moving means and a lifting means. Further, the winch 3 can be used as a lifting means, and the arm 11 can be raised or turned as a moving means.

By the way, in order to move the suspended load M to a predetermined target position, the arm 11 (or the winch 3 at the same time) must be operated. At this time, if the hoisting for ground cutting is to be carried out first, the hoisting rope 5 is started from the initial state (see Fig. 8(a)), similar to the above-mentioned state in which the trolley 1 is used (see Fig. 3). to raise (or wind up). As a result, a tensile force will act on the suspended load M, and the suspended load M will be drawn in the axial direction of the hoisting rope 5. When the angle θ ₁ of the hoisting rope 5 is large, the entire bottom surface of the suspended load M slides (planar slide) while being installed on the surface N of the loading place (see FIG. 8(b)). ). Moreover, after that, if the angle θ ₁ of the hoisting rope 5 becomes smaller, the planar sliding state ends. In addition, even in this case, depending on the relationship between the suspended load M and the hoisting rope 5, there is a possibility that planar sliding due to the entire bottom surface of the suspended load M does not occur. After that, since the lighter side (front end C in the figure) rises, only the other side (rear end D in the figure) is in contact with the mounting surface N (see FIG. 8(c)). Then, as the hoisting rope 5 is continuously raised (or wound up), the suspended load M is lifted off the ground.

Although not particularly shown, even in the case of the jib crane 10, a laser sensor for detecting the angle of the hoisting rope 5 is provided at the tip of the arm 11, and the angle and angular velocity of the arm 11 as well as the winch 3 The winding speed and the like are detected by an encoder or other detection device. It is also possible to transport the suspended load M by the jib crane 10 in this way, but since the transportation state of the suspended load M is substantially the same as that by the trolley 1, the following description will focus on transportation by the trolley 1. Let me explain. Therefore, hereinafter, the portions related to conveyance of the trolley 1 and hoisting of the hoisting rope 5 will be explained as including the case of changing the angle of the arm 11 in the jib crane 10 and operating the winch 3.

<Detection of ground break>
As mentioned above, even when transporting suspended loads M of various shapes, when hoisting only the hoisting rope with the trolley 1 stopped, the hoisting rope The angle θ ₁ of 5 gradually decreases. When hoisting a long rod-shaped hanging load M, the angle _θ1 of the hoisting rope 5 may temporarily increase, but it will eventually gradually decrease. In this embodiment, as described above, since the angle θ ₁ of the hoisting rope 5 is detected by the laser sensor 7, it is possible to detect that the ground cutting is in progress based on the amount of change in this angle θ ₁ . can.

That is, the suspended load M floating from the surface N of the loading place will swing around the trolley 1 (base point of the hoisting rope 5), and after the angle θ ₁ of the hoisting rope 5 has decreased to "0". , furthermore, a value of "-" is detected. Since the angular velocity of the angle change at this time is also detected, it is possible to detect that the angle θ ₁ is not simply decreasing based on the angular velocity when the angle θ ₁ of the hoisting rope 5 goes toward “0”. Since this state does not occur in the above-mentioned sliding (slide) and stopping (stick), it can be detected that this is an initial swing of the suspended load M after breaking off the ground. In this way, when the initial shake is detected, the movement of the trolley 1 is started and steady rest control is performed.

In addition to detecting the ground breaking state by the detected value of the angle θ ₁ of the hoisting rope 5 as described above, it may also be detected by an image, or by detecting a change in the attitude of the suspended load M by an IMU. However, it may be detected by detecting the angular velocity related to the inclination, the acceleration related to the movement, etc.

This means that if the control system is to move the trolley 1 from the beginning, that is, if the drive control of the trolley 1 and the hoisting control of the hoisting rope 5 are performed at the same time, grounding can be achieved by changing only the angle θ ₁ of the hoisting rope 5. Since it is difficult to determine the state of the suspended load M, the state of the suspended load M is detected by image processing or IMU to determine the state of breaking.

In the case of image detection, by analyzing the image obtained by the photographing means, the entire position of the suspended load M (the positions of the front end C and the rear end D) can be detected, and the state of the ground breaking can be detected. It can be detected. Furthermore, only the boundary part between the suspended load M and the surface N of the loading place is analyzed, and the threshold value is a state in which there is no continuous part between the two, and a gap has occurred in the entire range from the front end C to the rear end D. , the state of ground cutting may be detected.

In addition, in the case of detection by IMU, by detecting changes in the posture (inclination angle) of the suspended load M and changes in position associated with the inclination angle, it is possible to determine whether the suspended load M is rising due to the inclination or rising due to cutting off the ground. By distinguishing between the two, it is possible to detect the timing of ground cutting. In particular, since the suspended load M changes its posture but does not change its shape, if the initial position information of the IMU is given in advance and the inclination angle of the suspended load M and the height of the IMU are calculated, The heights of the front end C and the rear end D can be calculated. Based on the calculation result, a state in which both ends C and D have moved until they float can be detected as a ground break.

<Steady rest control>
As shown in FIGS. 9 and 10, the swing of the suspended load M is controlled by moving the trolley 1. As shown in FIGS. The control method is feedback control, and basically it detects the angle θ ₁ created between the hoisting rope 5 and the vertical direction and reduces this angle θ ₁ (eventually it becomes “0”). ”), the trolley 1 is moved in the forward and backward direction. The steady rest control based on the movement of the trolley 1 may be started during the ground cutting, but may also be started after the ground cutting. When the steady rest control is started after the ground is cut, the hanging load M is ground while changing its posture as described above, and immediately after that, the movement of the trolley 1 is controlled and the trolley 1 is transported to the target position. That will happen. Immediately after breaking the ground, the suspended load M begins to swing, and if it is determined that it is in a swinging state based on changes in the angle θ ₁ of the hoisting rope 5 (angle and angular velocity), steady rest control is performed by moving the trolley 1. is started. On the other hand, if the steady rest control is started during the ground cutting, the trolley 1 will move forward and backward during the ground cutting, and the steady rest control will also act on changes in the attitude of the suspended load M. However, in cases where the time during ground cutting (time from the start of control to ground cutting) is extremely short due to the hoisting speed of the hoisting rope 5, or when the attitude of the suspended load M is stable from the beginning, If there are circumstances, the state will be approximated to the state in which control is started after the ground has been cut.

The control method is such that when the angle θ ₁ of the hoisting rope 5 changes greatly, that is, when the angle θ ₁ changes from “+” to “0”, the angular velocity reaches “−” (see FIG. 9(a)). (see FIG. 10(a)), and the trolley 1 is moved forward according to the degree of "-". At this time, the forward speed (acceleration) is adjusted to prevent steady movement (see FIG. 9(b) and FIG. 10(b)). Further, by swinging back, the angle θ ₁ changes from "-" to "0" or "+" (see FIG. 9(c) and FIG. 10(c)). The trolley 1 is moved backward according to the extent to which the angular velocity reaches "+" at this time. Note that since the trolley 1 moves to the target position (transports the suspended load M), the hoisting rope 5 The purpose is achieved by moving the trolley 1 forward greatly when the angle θ ₁ changes from "+" to "0" and "-".

Furthermore, as shown in FIGS. 9 and 10, the attitude of the suspended load M after breaking the ground is such that the position of the center of gravity G is not necessarily on the extension line of the hoisting rope 5. In order to completely stabilize the suspended load M, it is necessary that the center of gravity G of the suspended load M be located on the extension line of the hoisting rope 5 with the hoisting rope 5 aligned vertically. Therefore, if the angle that the line connecting the tip of the hoisting rope 5 (the connection position with the slinging rope 6) and the center of gravity G has with respect to the vertical direction is θ ₂ , this angle θ ₂ will ultimately be “0”. ” is requested. Therefore, in the steady rest control by moving the trolley 1 back and forth, the angle θ ₂ is detected and the trolley 1 is moved so as to make it smaller. In this case as well, the trolley 1 is moved forward or backward in accordance with the angular velocity when the angle changes from "-" to "0" to "+". In reality, the specific advancing and retreating speed (acceleration) will be determined by adding up the change in the angle θ ₁ of the hoisting rope 5.

Note that the change in the angle θ ₂ related to the position of the center of gravity G can be obtained by changing the inclination angle by the IMU described above. Generally, the swing at the center of gravity G lags behind the swing of the hoisting rope 5, so it can be detected by comparison with the swing of the hoisting rope 5. Furthermore, since the change in the angle θ ₂ applied to the position of the center of gravity G (inherent swing of the suspended load M) is eventually converged by the change in the angle θ ₁ of the hoisting rope 5 (total swing), Even in the case of a configuration in which only the angle θ ₁ of the hoisting rope 5 is feedback-controlled, the steady rest control as a whole is possible.

In this way, since the trolley 1 is used to transport the trolley 1 to the target position, it detects the vibration caused by the transport and ultimately attenuates the vibration until the trolley 1 reaches the target position. Note that the movement of the trolley 1 is controlled by controlling the speed, and as a result, the acceleration of the trolley 1 is changed to stop the trolley from swaying. Moreover, since the trolley 1 is involved in transportation, it basically moves more in the forward direction, and depending on the conditions, it may repeat acceleration and deceleration without causing a backward phenomenon. This is due to the result that the acceleration of the trolley 1 for steady resting and the acceleration for transportation are added or subtracted.

Control related to the movement of the trolley 1 is performed by the output of a servo driver 92 to a servo motor (first driving means) 2 for the trolley, and hoisting control of the hoisting rope 5 is performed by a motor for driving the winch 3. This is similarly performed by the output of the servo driver 92 for the servo motor 4 . Therefore, the control signal is a voltage value for controlling the speed, and by changing this, acceleration control can be performed. Furthermore, the information of the encoders provided in both servo motors 2 and 4 is input to the processing unit 91 together with the angle information (angle and angular velocity) of the hoisting rope 5 obtained by the laser sensor 7, and the output of the servo motors 2 and 4 is controlled by feedback control. The value is controlled.

In the case of a configuration in which only the angle θ ₁ of the hoisting rope 5 is feedback-controlled, the length of the hoisting rope 5 is l ₁ , the length of the hoisting rope 5 at the target position is l d , and the length of the hoisting rope 5 is l 1 ; the length of the hoisting rope 5 at the target position is l _d ; 5 (angle with the vertical direction) is θ ₁ , the moving distance of trolley 1 is x , and the moving distance of trolley 1 and trolley 1 to the target position is x _d . On the other hand, the value of the acceleration to be controlled can be calculated using the following equation.

Note that k ₁ to k ₃ and K ₁ , K ₂ , α ₁ and α ₂ in the above equation represent respective control parameters, and the values of each parameter are k ₁ =14, k ₂ =16.5, k ₃ = 35, K ₁ = 5.95, K ₂ = 0.4, α ₁ = 1, α ₂ = 1.5.

As is clear from the above equation, the hoisting rope 5 is controlled to the target hoisting position (length) without being based on the angle of the hoisting rope 5, but the movement of the trolley 1 is controlled by the hoisting rope 5. It changes depending on the angle.

On the other hand, if the movement of the trolley 1 is to be controlled from the beginning, it is necessary to further consider the posture of the suspended load M, and the angle of the center of gravity G of the suspended load M (the angle between it and the vertical direction) is calculated, and the Setting the angle of the center of gravity to θ ₂ , the acceleration can be calculated using the following equation.

Note that k ₁ to k ₄ and K ₁ , K ₂ , α ₁ and α ₂ in the above equation represent respective control parameters, and the values of each parameter are k ₁ =14, k ₂ =16.5, k ₃ = 35, k ₄ = 5, K ₁ = 5.95, K ₂ = 0.4, α ₁ = 1, α ₂ = 1.5.

In this case as well, the hoisting rope 5 is controlled without being based on both angles, but the movement of the trolley 1 is controlled while changing the acceleration according to the state of change in both angles. .

Here, in the control during ground cutting, the attitude of the suspended load varies depending on the friction state between the bottom surface of the suspended load M and the surface N of the loading place, so in order to create a robust controller, the gain K is calculated. There is a need. Therefore, the gain K of the controller has eight modes depending on the state of the suspended load, and among these, there are six modes if the swing state is excluded. Therefore, K _i (i=1 to 6 (each slide and each stick)) is calculated. Furthermore, the frictional state μ is determined by the friction coefficients of the two in contact, and is determined for a plurality of frictional states (μ ₁ to μ _j ). This can be summarized as shown in the table below.

Here, in order to find the optimal controller gain K from among the plurality of friction states (μ ₁ to μ _n ) as described above, the gain K _i ^j (i= 1, 2, ... 6; j = 1, 2, ... n), and find the gain of the robust controller that minimizes θ ₁ and θ _2, as shown in the formula below. . The gains K _i ^j in the plurality of friction states in this case may be based on simulation or experiment. The goal is to find a common gain that can reduce the influence of friction under multiple assumed conditions. That is, as shown in the following formula, the gain of the controller that minimizes the evaluation function J is determined.

Note that after breaking the ground, the suspended load swings in the air and the friction state becomes irrelevant, so the gain of the controller that minimizes θ ₁ and θ ₂ is determined as shown in the equation below.

<Experiment 1>
Using the above-mentioned control system, we experimented with the state of steady rest control when lifting a suspended load from a loading location and transporting it to a target position. In this experiment, the height from the surface of the loading place to the trolley was 1.2 m, the weight of the approximately L-shaped (shape shown in Figure 1) when viewed from the front was 5 kg, and the length of the hoisting rope was 0. This is a simulation of the steady rest condition when hoisting up to 3 m and transporting by trolley to 1.2 m ahead. The configuration of the transport device and steady rest control system is as shown in Figure 1, and the tests were carried out for two cases: one in which the movement of the trolley was controlled at the same time as the hoisting rope started to be hoisted, and the other in which the movement of the trolley was controlled after the hoisting rope began to be hoisted. . The experimental results are shown in FIG. In the graphs in the figure, all horizontal axes are time (seconds), and the solid line indicates the case where steady rest control is performed from the time of breaking the ground, and the broken line indicates the case where steady rest control is started immediately after breaking the ground. It is. For comparison, FIG. 12 shows a state in which the device is lifted and conveyed to a predetermined position without steady rest control.

The winding speed of the hoisting rope was constant except for acceleration immediately after the start of hoisting and deceleration immediately before reaching a predetermined hoisting rope length. In addition, "Mode" indicates changes in the eight modes described above (a total of seven modes with one type of runout), and "0" to "6" on the vertical axis are as noted in the figure. , each aspect is shown.

Referring to this result, when the hoisting rope starts to be hoisted, after a short period of time when the hoisting rope stops due to the bottom surface of the load (planar stick), it becomes a sliding condition due to the bottom surface of the suspended load (planar slide), and then It can be clearly determined that the front end C is lifted up (off the ground) through a state in which only the front end C floats and slides (sliding state due to the rear end D: D-slide). Note that the time until ground cutting was approximately 1.7 seconds.

As shown in this figure, as a result of this experiment, hoisting the hoisting rope and moving the trolley reached the target position before reaching the target position approximately 8 seconds after the start of the operation, and the steady rest state was initially In the case of more control, the steady rest state is reached in about 8 seconds, and even in the case where control is started after the ground has been cut, the steady rest state is reached in about 10 seconds. On the other hand, when the suspended load was moved to the target position after about 8 seconds in an uncontrolled state (see Figure 12), it began to sway after reaching the ground, and the sway did not attenuate even after reaching the ground. . From the difference between the two, the effect of the steady rest control in this experimental example became clear.

Furthermore, according to the above experimental results, the angle θ ₁ of the hoisting rope and the angle θ ₂ of the center of gravity fluctuate to gradually decrease the angle for about 1.7 seconds until the rope is cut off. Later, it passes through "0" and reaches "-". Thereafter, as the trolley moved, the vibration was gradually attenuated, and the vibration was resolved after approximately 7 seconds when trolley control was performed from the beginning, and after 9 seconds when trolley control was performed after the ground crossing. At this time, the angle θ ₂ of the center of gravity immediately after the ground breaking fluctuates greatly, whereas the angle θ ₁ of the hoisting rope fluctuates relatively gently, except immediately after the ground breaking. This can be seen as an effect of initial swing due to ground cutting, but it can also be seen as a minute fluctuation in the large fluctuation of the angle θ ₁ of the hoisting rope as a whole. Therefore, the swing of the suspended load due to ground cutting changes the angle θ ₂ of the center of gravity, but as a result, the swing transmitted to the hoisting rope changes the angle θ ₁ of the hoisting rope. Therefore, it is determined that by controlling the movement of the trolley so as to reduce the angle θ ₁ of the hoisting rope, it is possible to attenuate both the shake caused by ground cutting and the shake caused by conveyance.

<Experiment 2>
An experiment was conducted under the same conditions as above, only changing the shape of the suspended load. In this experiment, a long rod-shaped suspended load was lifted and transported by connecting a hoisting rope to the front end, and other conditions were the same as in Experiment 1. The results are shown in FIG. The display of the horizontal axis, solid line, and broken line in the graph in the figure is the same as in the case of FIG. 11. For comparison, FIG. 14 shows a state in which the device is lifted and conveyed to a predetermined position without steady rest control.

Referring to this result, when the hoisting rope starts to be hoisted, initially only the front end C floats, the rear end D remains stationary (D-stitch), and then the rear end D causes the oscillation. It can be clearly seen that the ship has been lifted (off the ground) after going through a D-slide state. Note that the time until ground cutting was approximately 2 seconds.

As shown in this figure, as a result of this experiment, the hoisting rope was hoisted and the trolley moved to the target position before reaching the target position approximately 5 seconds after the start of the operation, and the steady rest state was eventually reached. Even in the control state, the steady rest state is reached after about 5 seconds. On the other hand, when the suspended load was moved to the target position after about 5 seconds in an uncontrolled state (see Figure 14), it began to sway after reaching the ground, and the sway did not attenuate even after reaching the ground. . In particular, after the ground breaking, there was not a regular runout but a small vibration, which is thought to be due to the mutual influence of the initial runout and the conveyance runout. In this way, it has become clear that steady rest can be achieved by the control according to this embodiment even under conditions where the initial runout greatly affects the conveyance runout.

Further, according to the above experimental results, the angle θ ₁ of the hoisting rope gradually increases for about 2 seconds until the rope is cut off, and then it is significantly reversed after the cut. On the other hand, the angle θ ₂ of the center of gravity, on the contrary, fluctuates so as to gradually become smaller, and fluctuates little by little after the grounding. After that, it is gradually attenuated by the movement of the trolley. At this time, the angle θ ₂ of the center of gravity immediately after the ground-off fluctuates little by little, whereas the angle θ ₁ of the hoisting rope fluctuates relatively gently. In this case as well, as in Experiment 1, there is an influence of initial deflection due to ground cutting, but overall this can be seen as a minute fluctuation in the large fluctuation of the angle θ ₁ of the hoisting rope. Therefore, as in Experiment 1, the swing of the suspended load due to ground cutting changes the angle θ ₂ of the center of gravity, but as a result, the swing transmitted to the hoisting rope changes the angle θ ₁ of the hoisting rope. This shows that by controlling the movement of the trolley to reduce the angle θ ₁ of the hoisting rope, it is judged that both the shake caused by ground cutting and the shake due to transportation can be attenuated. .

Although the embodiments and examples of the present invention are as described above, these are merely examples of the present invention, and the present invention is not limited to these embodiments. Therefore, the transportation means is not limited to a trolley, but may be any other self-propelled traveling body. Furthermore, although the embodiments of the present invention have been described with a focus on a trolley-type conveyance device, even in the case of a boom-type conveyance device (jib crane), ground cutting is performed in the same way, and the angle θ ₁ with respect to the hoisting rope is (and the angle θ ₂ of the suspended load) and by feedback control, it is possible to carry the load to the target position and keep it steady.

1 Trolley (transportation means)
2 Motor (first driving means)
3 Winch 4 Drive motor (second drive means)
5 Hoisting rope 6 Slinging rope 7 Laser sensor (rope angle detection means)
8 Inertial measurement unit (IMU)
9 Control device (control means)
10 Jib crane 11 Arm 21 Drive pulley 22 Followed pulley 23 Toothed belt 51 Hoisting rope tip 91 Processing section 92 Servo driver C Bottom end of suspended load (front end)
D End of the bottom of the suspended load (rear end)
G Center of gravity position of hanging load L Rail M Hanging load N Surface of loading place

Claims (4)

a hoisting means for hoisting a hoisting rope to hoist a suspended load;
A moving means for moving the suspended load together with the lifting means;
a first driving means for providing driving force to the moving means;
a second driving means for providing driving force to the lifting means;
rope angle detection means for detecting an angle in the axial direction of the hoisting rope;
A hoisting and conveying device that lifts a suspended load to a predetermined height and conveys it to a target position, the hoisting and conveying device comprising a control means for controlling the driving states of both the first and second driving means,
The hoisting and conveying device includes a hanging load angle detection means for detecting an inclination angle of the hanging load,
The control means includes, for the first drive means, a transport control section that controls the movement of the moving means from the start of driving until reaching the target position; a hoisting control section that controls lifting of the hoisting rope to a predetermined height; an axial angle and angular velocity of the hoisting rope detected by the rope angle detection means; and a hoisting load detected by the hoisting angle detection means. and a determination unit that determines the condition of the suspended load based on the inclination angle and angular velocity of the
The transport control unit controls the transport speed so as to guide the axial angle of the hoisting rope in the vertical direction while referring to the condition of the suspended load determined by the determination unit. Steady rest control system for hoisting and conveying equipment. The determination unit determines whether the suspended load is in a state of being cut off or after being cut off,
The steady rest control system for a hoisting conveyance device according to claim 1, wherein the conveyance control section starts control when the determination by the discriminating section indicates that the ground has been cut. a hoisting means for hoisting a hoisting rope to hoist a suspended load;
A moving means for moving the suspended load together with the lifting means;
a first driving means for providing driving force to the moving means;
a second driving means for providing driving force to the lifting means;
rope angle detection means for detecting an angle in the axial direction of the hoisting rope;
A hoisting and conveying device that lifts a suspended load to a predetermined height and conveys it to a target position, the hoisting and conveying device comprising a control means for controlling the driving states of both the first and second driving means,
The hoisting and conveying device includes a photographing means ,
The control means includes, for the first drive means, a transport control section that controls the movement of the moving means from the start of driving until reaching the target position; a lifting control unit that controls lifting of the rope to a predetermined height, an image acquisition unit that acquires an image photographed by the photographing means, an analysis unit that analyzes the image, and a rope angle detected by the rope angle detection means. and a determination unit that determines the condition of the suspended load based on the axial angle and angular velocity of the hoisting rope,
The determination unit determines, based on the image analyzed by the analysis unit, at least whether the suspended load is in a state of being cut off or after being cut off ,
The conveyance control section controls the conveyance speed so as to guide the axial angle of the hoisting rope in the vertical direction while referring to the condition of the suspended load determined by the discrimination section.
A steady rest control system for a hoisting conveyance device , characterized by : 4. The steady rest control system for a hoisting and conveying device according to claim 3, wherein the conveyance control section starts control when the determination by the discriminating section indicates that the ground has been cut.

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