TWI397492B - Mobile body, tower crane and tower crane lifting control method - Google Patents

Description

Lifting control method for mobile body, tower crane and tower crane

The present invention relates to vibration suppression of a moving body.

In a tower crane or an unmanned transport vehicle, there is a transport trolley such as a railcar, and an arm that can move forward and backward, such as a sliding fork or a non-vector arm, and an elevating table or a lifter, etc., are used to carry out the transfer of articles. In the top traveling vehicle, the article is clamped by the chuck of the lifting platform, and the lifting is performed to carry out the transfer. In any of these cases, it is required to suppress the vibration of the article during the transfer. When the vibration can be suppressed, the force applied to the article can be reduced during the transfer, the waiting time until the vibration is controlled can be shortened, the height accuracy at the time of transfer can be improved, and the rigidity of the transfer device can be small, and can be moved. The advantage of carrying heavy, easily damaged items, etc. However, in Patent Document 1 (Japanese Patent No. 3526014), it is proposed that in the transfer of a tower crane, when the sliding fork is in contact with the article, the speed is high, and from the vicinity of the start contact period, the lifting platform is raised at a low speed, and the article and the sliding are reduced. Impact when the fork is in contact.

Patent Document 1: Japanese Patent 3252014

A basic problem of the present invention is to perform required motion in a short period of time while suppressing vibration.

An additional object of the present invention is to transfer articles in a short period of time while suppressing vibration of articles.

An additional object of the present invention is to suppress vibration during the transfer of articles of a tower crane, and to form a transferable article in a short time, and to reduce an invalid space such as a scaffold for transferring the other party.

An additional object of the present invention is to provide a configuration of the above-described control system.

The moving body of the present invention is characterized in that: a position detecting means for detecting the position of the moving body, and a vibration detecting means for detecting the vibration of the moving body, and at least the movement of the object to be suppressed by the vibration are provided. The detection result of each of the above means is used to feed back a control unit that controls the drive mechanism of the moving body.

Preferably, the moving body is a transfer device including an article, and the position and vibration of the transfer device are detected by the respective detecting means, and the control unit performs an operation of feeding back the transfer device.

Preferably, the control unit includes a basic command generating means for generating a basic command for opening a loop of the drive mechanism, and a reference signal for converting the basic command into a reference signal of a position and an acceleration of the moving body. a means for generating, and a calculation means for calculating a position of the moving body and a vibration acceleration obtained by each of the detecting means, and an error of a position and an acceleration of the moving body obtained by the reference signal generating means, and calculating the basis The updating means for updating the estimated value of the state of the moving body, and the adding means for controlling the input to the driving means by adding a correction value to the estimated value of the state of the moving body.

The tower crane of the present invention belongs to a tower crane that carries an arm that can move forward and backward on a lifting platform that is lifted and lowered along a mast by a lifting motor, and is characterized in that a height sensor of the lifting platform is provided, and The acceleration sensor is disposed at the front end of the arm to detect the vibration of the front end of the arm portion, and is provided in the state of entering and exiting the arm portion, and the signal and acceleration sensor of the height sensor are used when the lifting platform is lifted and lowered. The signal is fed back to the control unit of the lift motor.

Preferably, the control unit includes a basic command generating means for generating a basic command for opening and closing the lifting motor, and a reference signal for converting the basic command into a height of the lifting platform and an acceleration of the arm portion. The reference signal generating means calculates the height of the lifting platform obtained by the height sensor and the vibration acceleration of the arm obtained by the acceleration sensor, and the reference signal generating means a means for calculating an error between the height of the lifting platform and the acceleration of the arm portion, and an updating means for updating the estimated value of the state of the lifting platform and the arm portion based on the calculated error, and the basic command according to the lifting table and the arm portion The estimated value of the state is added to the correction value, and the addition means used for the control input of the lift motor.

Further, in the present invention, the position and the vibration of the moving body are detected, and at least the motion of the vibration suppression target is fed back to the drive mechanism for controlling the moving body in accordance with the detection result of the position and the vibration, and the position of the movable body is controlled. vibration.

Moreover, the lifting and lowering control method of the tower crane according to the present invention is a lifting and lowering control method for a tower crane that carries an arm that can move forward and backward on a lifting platform that is lifted and lowered along a mast by a lifting motor, and is characterized in that: The height sensor detects the height of the lifting platform, and the acceleration sensor is disposed at the front end of the arm to detect the vibration of the front end of the arm, and when the lifting platform is lifted and lowered in and out of the arm, The signal of the height sensor and the signal of the acceleration sensor are fed back to control the lifting motor.

In the present invention, since the drive mechanism for controlling the moving body is fed back by the detection result of the position of the moving body and the vibration, the required movement can be performed in a short time while suppressing the vibration.

In particular, when the present invention is applied to the transfer operation of the transfer device, the transfer can be performed in a short time while suppressing the vibration applied to the article at the time of transfer.

Further, when the present invention is applied to the elevation control at the time of transfer of the elevator of the tower crane, the vibration of the tip end of the arm portion is suppressed, and the height of the lifting platform is reduced or the arm is reduced at least without increasing the vibration of the tip end of the arm portion. The deviation of the target height of the height of the front end can be transferred in a short time. Moreover, since the height of the front end of the elevating table or the arm can be accurately controlled, the dead space of the transfer partner or the like can be reduced.

Further, depending on the position and vibration obtained by the detecting means and the position and vibration error calculated from the basic command of the open loop, the state of the moving body is updated, and the deviation from the actual state of the basic command is determined. The state estimation value of the moving body can be corrected. Further, when the correction value based on the estimated value is corrected to the basic command by the addition means, the feedback control in response to the deviation from the basic command can be performed, and the movement of the moving body can be performed following the basic command.

In the following, the most suitable examples for carrying out the invention are shown.

Example

In the first to fifth figures, the control of the elevating table 4 of the tower crane 2 is taken as an example to show an embodiment and its characteristics. In each of the drawings, the elevating table 4 is guided to the mast 6 to be lifted and lowered, and the mast 6 is provided with a linear dimension 8 in the height direction, and the elevating table 4 is read by the line sensor 10 provided on the elevating table 4. Height position x0. Further, the lifting platform 4 is a belt type or a metal wire with a tooth, and the hanging material 12 such as a rope is suspended, and is lifted and lowered by the lifting motor 20 of Fig. 3 together with a weight (not shown).

22 is a sliding fork, and other arms such as a vectorless arm that can advance and retreat freely in a horizontal plane are also possible. 24 is an article support portion formed by the top plate of the slide fork 22, and 26 is an acceleration sensor provided on the article support portion 24. The scaffolding 28, 29 is a pillar thereof, and the article 32 is placed on the scaffolding seat 30 with respect to the traveling path of the tower crane 2.

Here, the tower crane 2 is transported as an article 32 between the scaffolding 28 and a workstation (not shown) as a weight of a liquid crystal substrate or the like. The liquid crystal substrate is easily damaged, and if the rigidity of the sliding fork 22 or the lifting table 4 is increased, the tower crane 2 becomes large and is less preferable. Further, since the scaffolding 28 and the like are disposed in the clean room, it is necessary to reduce the ineffective space for the transfer, and from the viewpoint of the productivity of the liquid crystal display panel, the cycle time of the transfer must be shortened.

The lifting and lowering operation at the time of transfer is explained by taking the picked-up article 32 as an example. The lifting table 4 is stopped at a position sufficiently lower than the bottom surface of the article 32 to advance the sliding fork 22. Thereafter, the article is raised at the first speed, and when the sliding fork 22 approaches the bottom surface of the article 32, the ascending speed is converted to the second speed of the minute speed, and the article 32 is transferred from the shelving base 30. When the article 32 is surely raised to the position transferred to the article support portion 24, it is accelerated to a third speed close to the first speed, then the rise is stopped, and the slide fork 22 is reset. Moreover, the remaining distance between the bottom surface of the article 32 and the sliding fork 22 is not measured, so that the correct timing of the article being transferred from the sliding fork 22 to the scaffolding seat 30 is unpredictable. The stroke of the cargo is related to the flexural amplitude of the sliding fork 22, and the stroke can be shortened if the amplitude is reduced. The scaffolding base 30 is provided with a plurality of upper and lower sides of the scaffolding 28. If the vibration of the sliding fork 22 is regarded as ±h, at least a margin of h is required in the scaffolding seat 30 to avoid interference with the scaffolding seat supporting the article. Moreover, in order to avoid interference of the article with the upper scaffolding seat, a margin of h is required, and an invalid space of 2 hours is required. First, the elevating table 4 is lifted and lowered at a slightly high speed, and then the article 32 is lifted and lowered at a slight speed, and the elevating table 4 is lifted and lowered at a slightly high speed, and the same is true at the time of unloading.

In Fig. 2, a control model of the lifting table and the articles on the sliding fork or the sliding fork is shown. The base of the mass m3 in which the posture is horizontally held, and the rigid body (mass m) which is joined by the pin at an inclination angle θ with respect to the inclination are modeled. Further, the rigid body and the base are connected by a spring k3 and a frictional resistance C3. The sliding fork and the article supported by the sliding fork are represented by a mass point m1, and are formed by connecting the spring k1 and the frictional resistance C1 to the rigid body. Moreover, the mass of the mass point m1 is rapidly changed by picking up the item. The lifting platform is connected to the counterweight (mass point m2) via the hanging material, and the counterweight is connected to the lifting motor by the hanging material. The spring constant of the suspension material between the counterweight and the lifting platform is taken as k2, and the frictional resistance is taken as C2. Further, the spring constant between the counterweight and the lift motor is taken as k4, and the frictional resistance is taken as C4. The absolute height of the base of the lifting platform is taken as x0, and the height of the front end of the sliding fork on the opposite coordinate with x0 as the reference is taken as x1, and the height of the weight is taken as x2, and from the weight to the command position of the lifting motor. The height is taken as x3.

The state X of the system of Fig. 2 is expressed by the four variables x0 to x3 indicating the height, and the time differentiation of these, as well as the inclination angle θ of the lifting platform and its time differentiation. Moreover, the state X is a state which shows the system which consists of a lifting platform and a sliding fork in a tower crane. Further, the variables F1 to F4 are determined as variables of the H ^∞ filter used for the strong control, and the state X is represented by a total of 14 variables. Also, u is a control input to the lift motor.

Fig. 3 shows the control system of the embodiment. The target height storage unit 34 is a pattern for storing the basic command for the lift motor 20, and is a pattern for elevating and lowering speed for loading or unloading while suppressing the vibration of the slide fork 22. However, the correct timing of handing over the article with the scaffolding seat is unclear. Therefore, in the model of Fig. 2, the mass of the mass point m1 is only the case of the sliding fork, or the sliding fork + article can suppress The basic command is determined in the natural vibration. The reference signal generating unit 36 is a two-dimensional reference signal ref formed by converting the basic command to the height of the lifting platform and the acceleration of the sliding fork of the lifting table. Moreover, the acceleration does not include the vibration component of the sliding fork.

The differentiator 38 is an error vector e formed by the difference between the signal of the output sensor 10, 26 and the reference signal ref, which is a representation of the displacement from the basic command by the height position of the lifting platform and the vibration of the front end of the sliding fork. . The multiplying means 44 multiplies the error vector by the rank B, and the multiplying means 48 multiplies the estimated value of the state X by the rank A, adds the adders 40, integrates by the integrating means 46, and updates the state X. The multiplying means 44 corrects the estimated value of the state X based on the error vector, and the multiplying means 48 corrects X in accordance with the estimated value of the state X itself. For example, the state Xm+1 at the time n+1 is the state Xn from the time n, represented by Xn+1=Xn+AXn+Ben, and the word added here indicates the time. When the time scale between the times is taken as Δ, the second term is considered, for example, Xn+1=(1+A.Δ+A ² /2.Δ ² )Xn+(B.Δ+B ² /2.Δ ² )en.

The multiplication means 50 is, for example, multiplied by the rank C in the state X of the 14-dimensional vector, and the output CX is generated. The output CX is based on the control input of state X, and the basic command FF is corrected in response to the displacement component from the height position of the basic command or the vibration acceleration. The multiplication means 52 multiplies the error vector e by the rank D and adds the output De to the control input. The adder 42 adds CX and De to the basic command FF as the control input u. Also, the De item is not set. The control input u is robust with H ^∞ control, and for the worst-case interference, the effect is below the specified value. Further, the degree of freedom in lifting and lowering the lifting platform is 5, but the feedback of the sensors 10 and 26 is performed on the vibration of the front end of the sliding fork and the height position of the lifting table. Therefore, the control of the embodiment is a strong control of 2 degrees of freedom.

Fig. 4 shows an operation waveform of the embodiment at the time of unloading. A) indicates an input speed command for the lift motor, and non-control indicates an example in which only the basic command is added but the feedback control is not performed, and the 2-degree-of-freedom robust control indicates that the line-sensing detector 10 and the acceleration sensing are added. The result of the feedback control of the device 26. In B), the deviation from the target height position of the lifting platform is indicated, and in C), the acceleration of the workpiece of the article to be transferred is indicated. Moreover, the unloading of the sliding fork from the scaffolding seat itself is performed in the vicinity of the first second of the time. It can be seen from Fig. 4C) that the degree of vibration applied to the workpiece is the same degree of shift in the embodiment or only the basic command, but in the embodiment, the height deviation of the lifting platform is almost 0 after the third time from the time. . Therefore, the lifting platform can be quickly lowered to the target height, and the sliding can be reversed, and the transfer time can be shortened. The basic command is designed to sufficiently suppress the vibration of the workpiece. Even if the additional feedback control is such that the height of the lifting platform quickly converges at the target position, the vibration of the workpiece is not increased.

Fig. 5 is a view showing the characteristics at the time of picking up the goods, and A) is an input speed command according to the command FF, and a speed command based on the two degrees of freedom strong control, and B) is a deviation indicating the target height position from the lift table, C ) is the acceleration indicating the front end of the sliding fork, and D) is the acceleration applied to the workpiece. The pickup is performed near the first second of the time, and correspondingly, the input speed command changes from the basic command FF in the vicinity of the first second. In the acceleration of the workpiece, there is a peak of acceleration in the second second of the time, and only the basic command FF, but in the embodiment, the peak disappears. Regarding the height of the lifting platform, in the embodiment, after the 5th second of the time, the deviation is almost 0, but the deviation is not eliminated only in the basic command FF.

In the embodiment, as described above, the deviation of the height position of the elevating table can be solved in a short time. The acceleration applied to the front end of the workpiece or the sliding fork with the picking or unloading is the same as the basic command. As a result, the workpiece can be transferred in a short time without applying a large impact to the front end of the workpiece or the sliding fork, and the positioning accuracy of the lifting platform is high, so that the ineffective space on the side of the scaffold can be reduced.

In the embodiment, the lifting platform of the tower crane will be described, but the carrying device without the vector arm or the sliding fork may be carried on the lifting platform which is lifted and lowered by the hanging material along the fixed guiding member. . Further, the same applies to the control of the stacker of the transfer device in which the sliding fork or the non-vector arm is carried on the stacker for transfer. In addition, the vibration suppression of the traveling control of the conveyance trolley such as a tower crane is similarly applicable to the embodiment. Further, from the top traveling vehicle body, the lifting material is suspended by the hanging material, and the lifting control of the lifting table for supporting the articles by the chuck is also applicable to the embodiment. At this time, the vibration of the front end of the sliding fork is replaced by the vibration of the lifting table in the lateral direction, and the lifting and lowering of the lifting table of the sliding fork can be replaced by the lifting and lowering of the lifting table of the overhead traveling vehicle. The H ^∞ control is used as an example of the strong control, but is not limited thereto, and H ² control or u control may be used.

At the front end of the sliding fork, a sensor that detects the distance of the article or the presence or absence of load from the article is provided, and the state can be estimated more accurately. Further, the height of the elevating table is not limited to a linear scale, but is an encoder that reads the rotational speed of the roller for the elevating guide of the elevating table, or an absolute distance sensor such as a laser distance meter. Also.

2. . . Tower crane

4. . . Lifts

6. . . Mast

8. . . Linear scale

10. . . Line sensor

12. . . Hanging material

16. . . Feedback controller

20. . . Lift motor

twenty two. . . Sliding fork

twenty four. . . Item support

26. . . Acceleration sensor

28. . . Scaffolding

29. . . pillar

30. . . Scaffolding

32. . . article

34. . . Target height memory

38. . . Differentiator

40,42. . . Adder

46. . . Integral means

44,48~52. . . Multiplication method

Fig. 1 is a view schematically showing an article of an elevator of an embodiment, a tower crane, and a scaffold.

Fig. 2 is a view showing a model of the embodiment from the command position to the lift motor to the slide fork.

Fig. 3 is a block diagram showing a feedback controller of the embodiment.

Fig. 4 is a view showing the characteristics of the embodiment at the time of unloading, A) is an input speed command, B) is a deviation of a basic command from a height position of the elevating table, and C) is an acceleration indicating an article.

Fig. 5 is a view showing characteristics of an embodiment at the time of stocking, A) is an input speed command, B) is a deviation of a basic command from a height position of the lift table, and C) is an acceleration indicating a front end of the slide fork, D) Is the acceleration of the item.

2. . . Tower crane

4. . . Lifts

6. . . Mast

8. . . Linear scale

10. . . Line sensor

twenty two. . . Sliding fork

twenty four. . . Item support

26. . . Acceleration sensor

28. . . Scaffolding

29. . . pillar

30. . . Scaffolding

32. . . article

12. . . Hanging material

Claims (4)

A moving body characterized by: a position detecting means for detecting a position of a moving body, and a vibration detecting means for detecting vibration of the moving body, and at least for the movement of the object to be suppressed by the vibration, in response to the above The detection result of the means is for feeding back a control unit for controlling a driving mechanism of the moving body, and the control unit is provided with a basic command generating means for generating a basic command for opening a loop of the driving mechanism, and for using the basic command a reference signal generating means for converting the position of the moving body and the reference signal of the acceleration, and calculating the position and the vibration acceleration of the moving body obtained by the respective detecting means, and the moving body obtained by the reference signal generating means a means for calculating the error of the position and the acceleration, and an updating means for updating the estimated value of the state of the moving body based on the calculated error, and adding a correction value to the estimated value of the state of the moving body based on the basic command The addition means used by the drive mechanism to control the input. The moving body according to claim 1, wherein the moving body is a transfer device including an article, and the position and vibration of the transfer device are detected by the respective detecting means, and the transfer is performed in the control unit. The action of the device. A tower crane belongs to a tower crane that carries an arm that moves forward and backward on a lifting platform that is lifted and lowered along a mast by a lifting motor, and is characterized in that a height sensor of the lifting platform is provided, and a sense of acceleration is provided. The detector is located at The front end of the arm detects the vibration of the front end of the arm, and is provided with the signal of the height sensor and the signal of the acceleration sensor, and the feedback control rises and falls when the lifting platform is lifted and lowered in the state of entering and leaving the arm. In the motor control unit, the control unit includes a basic command generating means for generating a basic command for opening and closing the lift motor, and a base command for converting the basic command into a height of the lift table and an acceleration of the arm portion. Referring to the reference signal generating means of the signal, and calculating the height of the lifting platform obtained by the height sensor and the vibration acceleration of the arm portion obtained by the acceleration sensor, and the reference signal generating means a means for calculating an error between the height of the lifting platform and the acceleration of the arm portion, and an updating means for updating the estimated value of the state of the lifting platform and the arm portion based on the calculated error, and the basic command according to the lifting table and The addition value of the state of the arm is added to the correction value, and the addition means for the control input of the lift motor. A lifting control method for a tower crane belongs to a lifting and lowering control method for a tower crane that carries an arm that moves forward and backward on a lifting platform that is lifted and lowered along a mast by a lifting motor, and is characterized in that: a height sensor Detecting the height of the lifting platform, and providing an acceleration sensor at the front end of the arm to detect the vibration of the front end of the arm, and moving the lifting platform up and down in the state of entering and leaving the arm, by using the height sensor Signal and acceleration sensor signal, feedback control lift motor, The basic command for generating the open loop of the lift motor is generated by the basic command generating means, and the reference signal is converted into a reference signal of the height of the lift platform and the acceleration of the arm by the reference signal generating means, and the calculation means calculates the height at the height. The height of the lifting table obtained by the sensor and the vibration acceleration of the arm obtained by the acceleration sensor, and the error of the height of the lifting platform and the acceleration of the arm obtained by the reference signal generating means And updating the estimated value of the state of the lifting platform and the arm portion based on the calculated error by the updating means, and adding the correction value to the estimated value of the state of the lifting platform and the arm portion by the adding means, for the lifting motor Make control inputs.