JP7455694B2 - Mobile object control method and mobile object control system - Google Patents

Description

The present disclosure relates to a mobile body control method and a mobile body control system that control the movement of a mobile body based on position information from a position information reading unit.

Conventionally, various techniques have been proposed for controlling the movement of a moving body based on position information from a position information reading unit (for example, Patent Document 1). The linear motor positioning device described in Patent Document 1 is provided with a positioning area where the movable element is positioned and a running area through which the movable element always passes. Additionally, a linear scale that can read position information is installed only in the positioning area. The positioning device executes sensorless vector control without using a linear scale in the travel region.

JP2004-23936A (Paragraph 0011)

The positioning device of Patent Document 1 described above performs sensorless vector control without using a linear scale by constantly moving the movable element at a constant speed in the travel region. For this reason, it is possible to eliminate the linear scale in a travel region where the movable element travels at a constant speed, but in a travel region where it is desired to change the position or speed of the movable element, it becomes necessary to install a linear scale. In other words, although it is desired to control the position and speed of the movable element, there is a possibility that the movement of the movable element cannot be appropriately controlled in a travel area where a linear scale cannot be installed.

The present disclosure has been made in view of the above-mentioned problems, and provides a method for controlling a moving object and a moving object control method that can perform control based on the position of the moving object even in a non-installed section where a position information reading unit is not installed. The challenge is to provide a system.

In order to solve the above problems, the present disclosure provides a method for controlling a moving body that moves along a rail, wherein the rail includes a stator, a first installation section in which a position information reading section is installed, a non-installed section in which the position information reading section is not installed; and a second installation section that is installed between the first installation section and the non-installation section and in which the position information reading section is installed. The movable body includes a movable element that generates thrust using magnetic force generated by the stator, and a position information reading section that reads position information from the position information reading section, A first control step of controlling the movement of the mobile body based on a reading position indicated by the position information read by the position information reading unit from the position information reading unit; a second control step of controlling the movement of the moving object based on the estimated position, and controlling the moving object based on the read position in the second installation section; and controlling the moving object based on the estimated position in the second installation section. Disclosed is a method for controlling a moving body, including a switching step of switching between the first control step and the second control step while performing both control of the moving object.
Further, the content of the present disclosure is useful not only as a method for controlling a moving body but also as a moving body control system including a rail and a moving body.

According to the mobile object control method and mobile object control system of the present disclosure, sensorless vector control is performed based on the estimated position of the mobile object in a non-installed section where no position information reader is installed. This makes it possible to control the position and speed of the moving object based on the estimated position even in non-installed sections. The movement of the moving object can be appropriately controlled even on a running road where a position information reading section cannot be installed.

It is a perspective view of the rail device and carrier with which the conveyance system of a present Example is equipped. 2 is a perspective view showing the inside of FIG. 1. FIG. FIG. 2 is a cross-sectional view of the rail device taken along a plane parallel to the Y direction and the Z direction. FIG. 3 is a side view of the carrier. FIG. 3 is a diagram showing the electrical configuration of the transport system. FIG. 1 is a schematic diagram showing an overview of a transport system. It is a figure which shows the state of switching between 1st control and 2nd control. It is a figure which shows the switching state of 1st control and 2nd control of another example.

Hereinafter, a transport system that is an embodiment of the mobile object control system of the present disclosure will be described. FIG. 1 shows a perspective view of a rail device 11 and a carrier 13 included in a transport system 10 (see FIG. 6), which will be described later. FIG. 1 shows a state in which a carrier 13 is placed on a linear rail device 11. As shown in FIG. 6, the transport system 10 is a system that moves the carrier 13 by driving a linear motor on a traveling path in which rail devices 11 of straight, curved, branched, etc. are combined with each other. The rail devices 11 having a straight line, a curve, a branch shape, etc. have the same configuration. Therefore, in the following explanation, the rail device 11 and carrier 13 having a straight running path shown in FIG. 1 will be explained, and the explanation of the rail device 11 having a curved shape, a branched shape, etc. will be omitted. In the following explanation, the direction in which the carrier 13 is slid in FIG. 1 is the X direction, the direction perpendicular to the The direction will be described as the Z direction.

As shown in FIGS. 1 to 3, the rail device 11 has a substantially U-shape that extends in the X direction and is open at the top in the Z direction. The rail device 11 includes a bottom portion 21, a first side wall 22, and a second side wall 23. A rail control unit 25 (see FIG. 3) is provided at the bottom 21 to control non-contact power supply. The first and second side walls 22 and 23 are provided on the upper surface of the bottom portion 21, face each other in the Y direction, and extend along the X direction. The rail device 11 includes a bottom portion 21, first and second side walls 22, 23, and forms a groove extending in the X direction. This groove is a travel path along which the carrier 13 moves.

The carrier 13 is housed in a groove surrounded by a bottom 21, a first side wall 22, and a second side wall 23. A plurality of permanent magnets 26 are attached to the inner walls of the first and second side walls 22, 23. The plurality of permanent magnets 26 are, for example, rectangular plate-shaped extending in the Z direction, and are arranged on the inner walls of the first and second side walls 22, 23 along the X direction, i.e., along the moving direction of the carrier 13, at a predetermined magnetic pole pitch. Each of the permanent magnets 26 has a different polarity (N pole and S pole) between adjacent ones in the X direction, for example, so that N poles and S poles appear alternately on the inner surface facing the carrier 13 in the Y direction. Note that Figures 2 and 3 show a state in which a cover 27 (see Figure 1) covering the carrier 13 side of the permanent magnet 26 has been removed. Also, Figure 2 shows a state in which the second side wall 23 on the front side in the Y direction has been removed.

Furthermore, a rail portion 28 is provided at the top of each of the first and second side walls 22 and 23. The rail portion 28 is, for example, a V-rail with a V-shaped sliding surface, and a groove roller 43 of the carrier 13, which will be described later, is attached to the rail portion 28. Furthermore, a linear scale 29 is attached to the inner wall of each of the first and second side walls 22 and 23. As shown in FIG. 4, a linear head 40 is attached to the carrier 13 at a position facing each of the linear scales 29 of the rail device 11 in the Y direction. As the carrier 13 moves in the X direction, the linear head 40 reads position information PI (see FIG. 5) indicating the position of the carrier 13 in the X direction from the linear scale 29. The linear head 40 outputs the read position information PI to the control device 50 of the carrier 13 (see FIG. 5). Hereinafter, the position indicated by the position information PI may be referred to as a reading position. Note that the mounting positions and numbers of the linear scale 29 and linear heads 40 shown in FIGS. 3 and 4 are merely examples. For example, the linear scale 29 may be provided on the upper surface of the first side wall 22. Further, the carrier 13 may be configured to include the linear head 40 on one side in the Y direction. Further, when the linear scale 29 and the linear head 40 are provided on both sides in the Y direction, either one of the reading positions can be adopted in controlling the carrier 13, or the reading positions read by each can be compared.

Further, on the upper surface of the bottom portion 21, a running rail 30 is provided which extends in the X direction and has a substantially U-shape with an open top. Furthermore, a power transmission coil section 31 that performs non-contact power supply is provided at the top of the bottom section 21 . The power transmission coil section 31 includes a coil holding section 33 extending in the X direction and a power transmission coil 35. Note that FIGS. 1 and 2 show a state in which the power transmission coil 35 is removed. The power transmission coil 35 is wound around a coil holding portion 33 extending in the X direction.

On the other hand, as shown in FIGS. 1 and 2, the carrier 13 includes a main body portion 41 and a workbench 42. As shown in FIGS. The main body portion 41 has a substantially box shape and has various devices built therein. The workbench 42 has a substantially plate shape that is long in the X direction, and is fixed to the upper part of the main body 41 . FIG. 4 is a side view of the carrier 13 viewed from the X direction, showing a state with a part of the main body 41 removed. As shown in FIGS. 2 and 4, a plurality of grooved rollers 43 are attached to the lower surface of the workbench 42. As shown in FIGS. Further, below the groove roller 43, the above-mentioned linear head 40 is attached.

Further, a plurality of running rollers 45 are attached to the lower surface of the main body 41. Each of the plurality of running rollers 45 rotates while contacting the running rail 30 from inside. The main body 41 of the carrier 13 is inserted into the substantially U-shaped groove of the rail device 11 with the workbench 42 disposed above the rail device 11 . Each of the plurality of groove rollers 43 is rotatably attached to a rail section 28 provided at the upper part of the first and second side walls 22 and 23. The carrier 13 is movable in the X direction by rotatably attaching the groove rollers 43 and the traveling rollers 45 to the rail device 11, and moves by placing articles (parts, etc.) on the workbench 42. In this embodiment, for example, as shown in the transport system 10 of FIG. 6, which will be described later, a plurality of carriers 13 move on a travel path 87 configured by connecting a plurality of rail devices 11. The plurality of carriers 13 stop at work process positions 93 and the like, and supply the articles 89 and move the articles 89 after assembly.

Further, as shown in FIG. 4, a power receiving coil section 47 that performs non-contact power supply is provided on the lower surface of the main body section 41. The power receiving coil section 47 includes a coil holding section 48 and a power receiving coil 49. The power receiving coil 49 is wound around a coil holding portion 48 extending in the X direction. When the carrier 13 is disposed within the rail device 11, the power receiving coil section 47 is disposed facing the power transmitting coil section 31 with a predetermined distance therebetween in the Z direction.

As shown in FIG. 5, the rail control unit 25 of the rail device 11 is connected to the power transmission coil 35 and changes the AC voltage supplied to the power transmission coil 35. The rail control unit 25 changes the AC voltage supplied to the power transmitting coil 35 to supply power from the power transmitting coil 35 to the power receiving coil 49 of the carrier 13 in a non-contact manner. Note that the power supply to the carrier 13 is not limited to contactless power supply, and a contact type power supply method may be used.

Further, as shown in FIGS. 2 and 4, a control device 50 and a winding section 53 are built into the main body section 41. Therefore, the conveyance system 10 of this embodiment is a so-called moving coil type linear motor in which the permanent magnet 26 is arranged on the rail device 11 and the winding part 53 is arranged on the carrier 13. Note that the conveyance system 10 may be a so-called moving magnet type linear motor.

Further, the carrier 13 of this embodiment moves based on the control data CT received from the management device 73 of the transport system 10. Furthermore, the carrier 13 performs sensorless vector control based on the estimated position depending on the section where a linear scale 29, which will be described later, is not installed. More specifically, as shown in FIG. 5, the control device 50 includes a voltage control section 51, a command generation section 52, a position/speed control section 54, a position estimation section 55, and a switching section 56. The voltage control section 51, the command generation section 52, the position speed control section 54, the position estimation section 55, and the switching section 56 may be realized by processing using hardware such as an IC or FPGA, or by executing a program on a CPU. This may be realized by software processing, or may be realized by combining hardware processing and software processing.

The management device 73 is capable of wireless communication with the carrier 13 via the command generation unit 52. For example, the command generation unit 52 transmits usage position information PI3 of the switching unit 56 indicating the position of the carrier 13, which will be described later, to the management device 73. For example, the management device 73 appropriately determines the destination of each carrier 13 in accordance with the work of the transport system 10. The management device 73 determines the current location of the carrier 13 based on the usage location information PI3 etc. received from the carrier 13, and determines the next destination. After determining the destination, the management device 73 includes information on the current position of the carrier 13, information on the target position indicating the destination, etc. in the control data CT, and transmits the control data CT to the command generation unit 52. The command generation unit 52 sets, for example, a target speed, target acceleration, etc. for movement to the target position, based on the current position and target position received from the management device 73. The command generation unit 52 outputs information on the set target speed and target acceleration to the position and speed control unit 54. Note that the carrier 13 may be equipped with a GPS device or the like, and may detect information on the current position in its own device.

Further, the position and speed control unit 54 of the control device 50 changes the torque command for the torque control of the voltage control unit 51 based on the usage position information PI3 input from the switching unit 56. The used position information PI3 is information indicating the position of the carrier 13, and is position information determined by the switching unit 56 based on the position information PI and estimated position information PI2 of the position estimating unit 55, which will be described later. The position and speed control section 54 detects the speed and acceleration of the carrier 13 based on the used position information PI3, and outputs a torque command to the voltage control section 51 so as to achieve the target speed and target acceleration input from the command generation section 52. (for example, target torque, torque (thrust) constant, etc.).

The voltage control unit 51 outputs a voltage command value CV to the winding unit 53 and controls the voltage and current applied to the winding unit 53. As shown in FIGS. 2 and 4, the winding portions 53 are provided on both sides of the main body portion 41 in the Y direction, and are provided at positions facing the permanent magnets 26. In the winding portion 53, a coil 53B is wound around each of the plurality of yokes 53A (see FIG. 2). As shown in FIG. 5, a detection section 57 is attached to the winding section 53 to detect a current value A1 flowing through the coil 53B. The detection unit 57 outputs the detected current value A1 to the voltage control unit 51. The voltage control unit 51 outputs a voltage command value CV based on the torque command input from the position speed control unit 54 and the current value A1 input from the detection unit 57 to the winding unit 53, and energizes the winding unit 53. Feedback control of alternating current. Further, the voltage control unit 51 detects the position of the permanent magnet 26 based on the usage position information PI3 input from the switching unit 56. The voltage control unit 51 controls the current in the winding part 53 based on the detected position (polarity position) of the permanent magnet 26 and the position of the magnetic pole of the winding part 53, and switches the magnetic pole of the winding part 53.

The winding unit 53 generates a magnetic field by changing the voltage applied to the coil 53B and the alternating current flowing through the coil 53B based on the voltage command value CV input from the voltage control unit 51 (inducing N and S poles). A thrust force (magnetic attraction force or magnetic repulsion force) is generated between the permanent magnet 26 of the rail device 11 and the permanent magnet 26 of the rail device 11. Thereby, the control device 50 controls the direction and speed in which the carrier 13 is moved.

Further, the management device 73 is connected to the rail control section 25 of each rail device 11, and controls the rail control section 25 based on the usage position information PI3 etc. received from the carrier 13. The management device 73 controls contactless power feeding from the power transmission coil 35 of the rail device 11 to the power reception coil 49 of the carrier 13 in accordance with the movement of the carrier 13.

Further, the position estimating unit 55 estimates the current position of the carrier 13. The position estimation unit 55 estimates the current position of the carrier 13 based on, for example, the voltage command value CV input from the voltage control unit 51 and the current value A1 input from the detection unit 57. The position estimating unit 55 outputs estimated position information PI2 indicating the estimated value to the switching unit 56. Further, the switching unit 56 inputs position information PI from the linear head 40. As described later, the switching unit 56 determines whether to use the position information PI, the estimated position information PI2, or both as the used position information PI3, depending on the section where the linear scale 29 is not installed. Switch whether to do it or not. Thereby, in the section where the linear scale 29 is not installed, sensorless vector control that controls the movement of the carrier 13 based on the estimated position information PI2 can be performed without using the linear head 40. Note that the method for estimating the position of the carrier 13 is not particularly limited. For example, the position estimation unit 55 may detect a change in the magnetic field generated in the coil 53B from the voltage applied to the winding part 53 or the current flowing through the winding part 53, and estimate the position based on the change in the magnetic field. .

Further, the position estimation unit 55 inputs position information PI from the linear head 40. The position estimation unit 55 corrects errors in estimating the estimated position information PI2 based on the position information PI. The read position of the position information PI is information indicating the actual position of the carrier 13, which is obtained by reading the linear scale 29 with the linear head 40. The position estimation unit 55 corrects variables, coefficients, processing details, etc. in the estimation process so that the read position matches or approximates the estimated position indicated by the estimated position information PI2. The position estimating unit 55 periodically executes the correction process in a section where the linear scale 29 can be read by the linear head 40. Thereby, the accuracy of estimation can be improved.

FIG. 6 schematically shows an overview of the transport system 10. As shown in FIG. 6, the transport system 10 includes, for example, a traveling path 87 by connecting a plurality of rail devices 11 to each other. The carrier 13 travels on the travel path 87 based on instructions from the management device 73. A plurality of work robots 91 are arranged on the travel path 87 of the transport system 10. The work robot 91 is, for example, an articulated robot and performs various tasks. The carrier 13 stops, for example, at a work process position 93 of each work robot 91. The work robot 91 performs work on an article 89 placed on the workbench 42.

Here, as shown in FIG. 2, the rail device 11 of this embodiment is provided with a linear scale 29 along the X direction, which is the moving direction of the carrier 13. Further, as described above, the transport system 10 connects the plurality of rail devices 11 to each other to form the travel path 87. In this case, there may be a section where the linear scale 29 is not provided at the boundary portion (connection portion) between adjacent rail devices 11. For example, as shown in FIG. 6, the rail device 11 has a first installation section SC1 in which the linear scale 29 is installed, and a non-installation section SC3 having a section in which the linear scale 29 is not installed. Furthermore, in this embodiment, the section between the first installation section SC1 and the non-installation section SC3, where the linear scale 29 is installed, is set as the second installation section SC2 in which control switching is performed. In the following explanation, the control executed by the position speed control section 54 and the voltage control section 51 based on the read position of the position information PI will be referred to as first control, and the control executed by the position speed control section 54 and the voltage control section 51 based on the estimated position of the estimated position information PI2 will be referred to as first control. The sensorless vector control executed by 54 and the voltage control unit 51 will be described as second control.

FIG. 7 shows the state of switching between the first control and the second control. The vertical axis in FIG. 7 indicates the ratio (degree) used for controlling the movement of the carrier 13 as a weight for each of the first control and the second control. 100 on the vertical axis indicates that one of the controls is executed with a weight (ratio) of 100%. In this case, the other control is 0% on the vertical axis, and that control is not being executed. The horizontal axis indicates the position of the carrier 13. A waveform L1 indicated by a solid line indicates the weight of the first control. Furthermore, a waveform L2 indicated by a broken line indicates the weight of the second control.

In the following description, for convenience of explanation, the source rail device 11 will be referred to as a first rail device 11A, and the destination rail device 11 will be referred to as a second rail device 11B, as an example, as shown in FIG. . FIG. 7 shows, for example, a state in which the carrier 13 moves from left to right from the first rail device 11A to the second rail device 11B.

The position P1 is at the boundary between the first installation section SC1 and the second installation section SC2 in the first rail device 11A as the movement source. The control device 50 of the carrier 13 controls movement only by the first control in the first installation section SC1 until reaching the position P1. That is, since the linear scale 29 can be read until the position P1, movement is controlled only by control based on the read position. Further, the control device 50 also performs estimation by the position estimation unit 55 in the first installation section SC1, and performs a process of correcting an error in the estimation of the estimated position information PI2 in parallel with the movement control by the first control. Thereby, the estimated position can be made to match the reading position as much as possible in the first installation section SC1.

Furthermore, the position P2 is the position of the boundary between the second installation section SC2 and the non-installation section SC3. When the control device 50 reaches the position P1 and enters the second installation section SC2, it starts switching between the first control and the second control, and completes the switching by the position P2. Further, the end point P3 indicates the end of the linear scale 29 of the first rail device 11A. For example, when the control device 50 detects that the linear scale 29 has reached the position P1 a predetermined distance 61 from the end point P3 based on the use position information PI3 (position information PI) in the first installation section SC1, Start the switch. The distance 61 may be a uniform value for all rail devices 11, or may be a different value depending on the installation status of the linear scale 29 of the rail device 11.

Furthermore, the method for determining the timing to start switching is not limited to the method using the distance 61 from the end point P3 described above. For example, the control device 50 may determine the switching timing based on a position at a predetermined distance from the starting point, midpoint, or the like of the linear scale 29. Further, the control device 50 may obtain the timing to start switching from another device, such as the rail device 11 or the management device 73, for example. For example, each time the carrier 13 enters a new rail device 11, it may acquire information on the position P1 at which switching starts from the new rail device 11.

The control device 50 switches between the first control and the second control in stages in the second installation section SC2. For example, the switching unit 56 calculates and outputs the usage position information PI3 every time the usage position information PI3 is output to the position speed control unit 54 and the voltage control unit 51 a predetermined number of times. The switching unit 56 calculates the value of the position indicated by the usage position information PI3, for example, using the following equation.
Value of used position information PI3=K1*value of reading position of position information PI+K2*value of estimated position of estimated position information PI2 In the above formula, K1 is the first weighting coefficient for the reading position of position information PI. K2 is a second weighting coefficient for the estimated position of the estimated position information PI2.

For example, the switching unit 56 changes the first weighting coefficient K1 to 1, 0.9, 0.8, 0.7...0.1, 0 every time the usage position information PI3 is output a predetermined number of times. and decrease it by 0.1. Moreover, the switching unit 56 changes the second weighting coefficient K2 to 0, 0.1, 0.2, . . . 0.8, 0.9, 1, 0, . Increase by 1. The weighting coefficients are the first weighting coefficient K1=1 and the second weighting coefficient K2=0 at the position P1, and the first weighting coefficient K1=0 and the second weighting coefficient K2=1 at the position P2. As a result, the ratio between the read position and the estimated position relative to the used position information PI3 changes relatively (inversely proportionally). The position speed control section 54 and the voltage control section 51 execute control using the used position information PI3, so that the weights of the first and second controls in the control of the winding section 53 can be changed in stages. can. Note that the control device 50 may execute the correction process of the estimated position information PI2 based on the above-described position information PI while performing the switching in the second installation section SC2.

The timing of changing the weighting coefficient in the second installation section SC2 is not particularly limited. For example, the switching unit 56 may change the weighting coefficient each time the usage position information PI3 is output. In this case, the weighting coefficient is changed only 11 times in the second installation section SC2. Alternatively, the switching unit 56 may, for example, reduce the amount of change in the first and second weighting coefficients K1 and K2 at the initial stage of entering the second installation section SC2, and gradually increase the amount of change. Specifically, the switching unit 56 sets the first weighting coefficient K1 to 1, 0.99, 0.98, 0.97...0.91, 0.9, 0.85, 0.8, 0. 7...0.1, 0, and the second weighting coefficient K2 is 0, 0.01, 0.02, 0.03...0.09, 0.1, 0.15, It may be changed to 0.2, 0.3...0.9, 1. Furthermore, the number of times the first and second weighting coefficients K1 and K2 are changed and the length of the second installation section SC2 are determined based on the cycle of feedback control using the position information PI3 of the position speed control unit 54 and the voltage control unit 51. You can also set

As shown in FIG. 7, the control device 50 sets the first weighting coefficient K1=0 and the second weighting coefficient K2=1 at position P2, and completes the switching from the first control to the second control. The control device 50 executes sensorless vector control (second control) based on the estimated position in the non-installation section SC3 from position P2 to position P5.

Further, P7 in FIG. 7 indicates the boundary between the first rail device 11A and the second rail device 11B. For example, the boundary P7 is the midpoint of the non-installation section SC3. In this embodiment, the end point P3 of the linear scale 29 is located outside (on the boundary P7 side) of the position P2 (the end point of the second installation section SC2). In other words, there is a section in which the linear scale 29 is provided in a part of the non-installation section SC3. Thereby, the reading of the linear scale 29 can be reliably executed until the switching is completed at the position P2. Note that the end point P3 and the position P2 may be made to coincide. In this case, the entire non-installation section SC3 may be a section in which no linear scale 29 is installed.

The carrier 13 moves in the non-installation section SC3, and transfers from the source first rail device 11A to the destination second rail device 11B at the boundary P7. When the control device 50 reaches position P5, which is the starting point of the second installation section SC2 of the second rail device 11B, it starts switching from the second control to the first control. For example, similarly to the position P1, the control device 50 detects that the position P5, which has passed a predetermined distance 62 from the starting point P4 of the linear scale 29 of the second rail device 11B, is reached based on the use position information PI3. Then, the switching begins. Note that the control device 50 may detect the position P5 using a method other than the distance 62. For example, the control device 50 may detect a position a predetermined distance away from the end point P3 as the position P5, and start switching. Further, the starting point P4 and the position P5 may be made to coincide with each other. For example, the control device 50 may start switching when the linear scale 29 of the second rail device 11B can be read, that is, when the starting point P4 of the linear scale 29 is detected.

Similarly to the switching from the first control to the second control in the second installation section SC2, the control device 50 increases the first weighting coefficient K1 while decreasing the second weighting coefficient K2, and gradually switches from the second control to the first control. Switch to control. At position P6, which is the end point of the second installation section SC2 of the second rail device 11B, the control device 50 sets the first weighting coefficient K1=1 and the second weighting coefficient K2=0, and switches the second control to the first control. Complete the switch. Similarly, the control device 50 executes the above-described switching control every time the rail device 11 moves between the rail devices 11 forming the travel path 87.

Here, the section without the linear scale 29 that occurs at the boundary P7 of the rail device 11 (the section between the end point P3 and the start point P4 in FIG. 7) is a short section where the carrier 13 travels for less than 1 second. Might happen. However, even in such a short section, loss of position information may cause unstable control and vibration in the carrier 13. On the other hand, in the carrier 13 of this embodiment, by switching to sensorless vector control that does not use the linear scale 29 according to the non-installed section SC3 where the linear scale 29 is not installed, the vibration of the carrier 13 is suppressed and stable. The carrier 13 can be run.

Furthermore, in the switching control in the second installation section SC2 (an example of the switching process of the present disclosure), the control device 50 of the present embodiment performs the first control based on the reading position and the second control based on the estimated position in stages. Switch. Depending on the accuracy of the estimation process, an error may occur between the estimated position and the read position read from the linear scale 29. When an error occurs between the estimated position and the read position, vibration may occur in the carrier 13 if the first control based on the read position and the second control based on the estimated position are switched exclusively. Therefore, by switching between the first control and the second control in stages, it is possible to suppress fluctuations in the use position information PI3 used for control and suppress the occurrence of vibrations in the carrier 13.

Note that the control device 50 does not need to switch between the first control and the second control in a stepwise manner. For example, as shown in FIG. 8, the control device 50 may stop the first control at position P2 and start the second control based on the estimated position. Specifically, the first weighting coefficient K1 may be switched from 1 to 0, and the second weighting coefficient K2 may be switched from 0 to 1. As described above, the control device 50 corrects the estimated position in the first installation section SC1. Therefore, the estimated position is highly likely to match or be similar to the read position. Therefore, switching from the first control to the second control is performed at once. On the other hand, when switching from the second control to the first control, an error may occur between the estimated position and the read position during the second control (during the non-installation section SC3). Therefore, as shown in FIG. 8, in the second installation section SC2 of the second rail device 11B, which is the destination, the second control is switched to the first control in stages. Note that when switching from the second control to the first control, the switching may be performed all at once instead of in stages.

Further, as described above, the control device 50 uses the sum of the value obtained by multiplying the reading position value by the first weighting coefficient K1 and the value obtained by multiplying the estimated position value by the second weighting coefficient K2. Controls movement of carrier 13. The control device 50 switches between the first and second control in a stepwise manner by increasing one of the first and second weighting coefficients K1 and K2 in a stepwise manner and decreasing the other in a stepwise manner. According to this, by relatively changing the weighting coefficients to be multiplied by each of the reading position value and the estimated position value, the ratio between the reading position and the estimated position in the used position information PI3 used for controlling the carrier 13 is adjusted in stages. can be changed accordingly.

Further, as shown in FIG. 7, the control device 50 performs the first and second controls in stages in both cases of switching from the first control to the second control and switching from the second control to the first control. I'm switching over. According to this, it is possible to perform control switching in stages and suppress generation of vibration of the carrier 13 both when entering the non-installation section SC3 and when exiting from the non-installation section SC3.

Moreover, the linear scale 29 is installed along the moving direction of the carrier 13 (the X direction in this embodiment) in the first installation section SC1 and the second installation section SC2. When the carrier 13 reaches a position P1 that is a predetermined distance 61 away from the end point P3 of the linear scale 29, the control device 50 starts switching from the first control to the second control. Further, when the carrier 13 reaches a position P5 that is a predetermined distance 62 away from the starting point P4 of the linear scale 29, the control device 50 starts switching from the second control to the first control.

According to this, for example, when the carrier 13 reaches positions P1 and P5 that are separated by predetermined distances 61 and 62 from the end point P3 and the start point P4, switching is started. This makes it possible to unify the switching start position and simplify the control details required for switching.

Furthermore, the control device 50 corrects an error in estimating the estimated position in the first installation section SC1 based on the reading position and the estimated position. According to this, the estimated position is estimated also in the first installation section SC1 where the linear scale 29 is installed, and the error in estimating the estimated position is corrected based on the reading position and the estimation. Switching can be performed by reducing the error between the estimated position and the reading position. Note that the control device 50 may perform the above-described correction process in at least one of the first installation section SC1 and the second installation section SC2.

In addition, in the rail device 11 of this embodiment, the linear scale 29 is installed along the moving direction of the carrier 13, and the outside of the terminal point P3 of the linear scale 29 in the moving direction is a non-installed section SC3 (non-installed section SC3), and connects the non-installed section SC3 to another rail device 11 to form a running path 87 for the carrier 13.

For example, when a plurality of rail devices 11 are connected to each other to form one travel path 87, it may be structurally difficult to install the linear scale 29 at the joint portion. If the position information is lost even if the distance between the joints is small, the carrier 13 may vibrate during or after passing through the joints. Therefore, in such a configuration in which a plurality of rail devices 11 are connected to each other, the carrier 13 can be stably moved between the rails by switching to sensorless vector control based on the estimated position. As a result, rail devices 11 of various shapes can be easily connected, and the degree of freedom in the shape of the running path 87 can be improved.

Further, the carrier 13 of the present embodiment includes a coil 53B as a movable element, a voltage control unit 51 that controls the power supplied to the coil 53B, and a current value A1 generated in the coil 53B (an example of the power value of the present disclosure). a position estimation section 55 that estimates the estimated position based on the voltage command value CV that controls the electric power supplied to the coil 53B by the voltage control section 51 and the current value A1 detected by the detection section 57; , is provided. According to this, in the moving coil type carrier 13, the estimated position is estimated based on the voltage command value CV of the voltage control section 51 and the current value A1 of the detection section 57. Therefore, control switching can be performed on the carrier 13 side. Note that the control switching determination may be performed by other devices such as the rail control unit 25 or the management device 73. For example, the management device 73 may instruct the carrier 13 about the switching timing and the first and second weighting coefficients K1 and K2 based on the usage position information PI3 received from FIG.

Incidentally, the transport system 10 is an example of the mobile object control system of the present disclosure. The rail device 11, the first rail device 11A, and the second rail device 11B are examples of rails. The carrier 13 is an example of a moving body. Permanent magnet 26 is an example of a stator. The linear scale 29 is an example of a position information reading section. The linear head 40 is an example of a position information reading section. Coil 53B is an example of a movable element. The end point P3 and the start point P4 are examples of end points of the position information reading section. The voltage command value CV is an example of a control value. Current value A1 is an example of a power value.

As described above, the present embodiment described above provides the following effects.
In one aspect of the present embodiment, the control device 50 of the carrier 13 controls the movement of the carrier 13 in the first installation section SC1 based on the read position indicated by the position information PI read from the linear scale 29 by the linear head 40. (An example of the first control step and first control process of the present disclosure). Further, the control device 50 performs sensorless vector control of the movement of the carrier 13 in the non-installation section SC3 based on the estimated position of the carrier 13 (an example of a second control step and second control process of the present disclosure). . Then, in the second installation section SC2, the control device 50 performs both the first control based on the reading position and the second control based on the estimated position, and switches between the first and second control. (An example of the switching process and switching process of the present disclosure).

According to this, in the second installation section SC2 between the first installation section SC1 and the non-installation section SC3, two controls are performed while executing the first control based on the reading position and the second control based on the estimated position. Execute the switch. In the non-installation section SC3 where the linear scale 29 is not installed, sensorless vector control is performed based on the estimated position. Thereby, even in the non-installation section SC3, the position and speed of the carrier 13 can be controlled based on the estimated position. Even on the travel path 87 where the linear scale 29 cannot be installed, the movement of the carrier 13 can be appropriately controlled.

Note that the present application is not limited to the above-mentioned embodiments, and can be implemented in various forms with various changes and improvements based on the knowledge of those skilled in the art.
For example, in the above embodiment, a so-called moving coil type structure is adopted as the structure of the linear motor, but the structure is not limited to this. A moving magnet system may be adopted as the structure of the linear motor. In this case, a coil can be used as the stator of the present disclosure, and a permanent magnet can be used as the mover. Further, for example, the rail control unit 25 of the rail device 11 may control the first and second wires based on the read position and the estimated position in controlling the winding portion 53 provided in the rail device 11, similar to the control device 50 of the above embodiment. Switching of the second control may also be performed.
Further, in the above embodiment, sensorless vector control is applied only to a small section of the boundary P7 of the rail device 11, but the invention is not limited to this. For example, in controlling the movement of the carrier 13, a section where high accuracy is required by control, such as movement of a curve or a branch point, may be set as the first installation section SC1, and the first control may be executed. Further, the second control may be performed by setting a section where high accuracy is not required, such as constant speed movement or constant acceleration/deceleration movement, to the non-installation section SC3.

In the above embodiment, the first and second controls are switched in stages using the first and second weighting coefficients K1 and K2, but other methods may be used. For example, the control device 50 may switch the first and second control in stages using combinations of several ratios such as 1:9, 4:5, 6:3, and 10:0.
Further, the control device 50 does not need to perform the estimated position correction process in the first installation section SC1 and the second installation section SC2.
Further, the rail device 11 is not limited to a configuration in which the running path 87 is formed by combining a plurality of rail devices 11. The rail device 11 may have a configuration including a plurality of first installation sections SC1, second installation sections SC2, and non-installation sections SC3 (a section with and without the linear scale 29) in one rail device 11.

The voltage control section 51 controls the voltage of the winding section 53 using the voltage command value CV, and controls the voltage value applied to the coil 53B and the current value flowing through the coil 53B. The voltage value and current value of the coil 53B may be controlled based on the current value by outputting the value.
The detection unit 57 may detect the voltage value of the coil 53B and output it to the voltage control unit 51 and the position estimation unit 55.
Although the carrier 13 that transports the article 89 on the travel path 87 of the rail device 11 is employed as the moving body of the present disclosure, the present disclosure is not limited thereto. The movable body of the present disclosure may be, for example, a movable body of a slider device that moves a work head in the X-axis direction or the Y-axis direction in an XY robot. Therefore, the moving object may be a moving object that does not transport the article 89 or the like.

10 conveyance system (moving object control system), 11 rail device (rail), 11A first rail device (rail), 11B second rail device (rail), 13 carrier (moving object), 26 permanent magnet (stator), 29 linear scale (position information reading section), 40 linear head (position information reading section), 50 control device, 51 voltage control section, 53B coil (mover), 55 position estimation section, 57 detection section, 61, 62 distance , SC1 first installation section, SC2 second installation section, SC3 non-installation section, P1 position, P5 position, PI position information, K1 first weighting coefficient, K2 second weighting coefficient, P3 end point (end point), P4 starting point (endpoint).

Claims (9)

A method for controlling a moving object moving along a rail, the method comprising:
The said rail is
a stator;
a first installation section in which the position information reading section is installed;
a non-installed section having a section where the position information reading section is not installed;
a second installation section installed between the first installation section and the non-installation section, and in which the position information reading section is installed;
Equipped with
The mobile body is
a mover that generates thrust using magnetic force generated by the stator;
a position information reading unit that reads position information from the position information reading unit;
Equipped with
In the first installation section, a first control step of controlling movement of the mobile body based on a reading position indicated by the position information read by the position information reading unit from the position information reading unit;
a second control step of performing sensorless vector control of the movement of the mobile body in the non-installation section based on the estimated position of the mobile body;
In the second installation section, the first control step and the second control step are performed while controlling the moving body based on the reading position and controlling the moving body based on the estimated position. a switching step for performing switching;
A method of controlling a moving object, including: The switching step includes:
2. The method of controlling a moving object according to claim 1, wherein control is performed in the second installation section to stepwise switch between control based on the read position and sensorless vector control based on the estimated position. The switching step includes:
Controlling the movement of the moving object using a total value obtained by adding a value obtained by multiplying the value of the reading position by a first weighting coefficient and a value obtained by multiplying the value of the estimated position by a second weighting coefficient, The control based on the reading position and the sensorless vector control based on the estimated position are switched in stages by increasing one of the weighting coefficient and the second weighting coefficient in stages and decreasing the other in stages. Item 2. The method for controlling a moving body according to item 2. The switching step includes:
When moving the movable body from the first installation section to the non-installation section via the second installation section, switching from the first control step to the second control step, and switching from the non-installation section to the non-installation section. Control based on the reading position in both cases of switching from the second control process to the first control process when moving the movable body to the first installation area via the second installation area; The method of controlling a moving body according to claim 2 or 3, wherein sensorless vector control based on the estimated position is switched in stages. The position information reading unit is
installed along the moving direction of the moving body in the first installation section and the second installation section,
The switching step includes:
When the moving object reaches a position a predetermined distance away from the end point of the position information reading section, it is assumed that the moving object has reached the second installation section, and switching between the first control step and the second control step is started. , A method for controlling a moving body according to any one of claims 1 to 4. In at least one of the first installation section and the second installation section, the estimated position is estimated, and the read position read by the position information reading section from the position information reading section and the estimated position are The method for controlling a moving body according to any one of claims 1 to 5, further comprising a correction step of correcting an error in estimating the estimated position based on the estimated position. The said rail is
The position information reading section is installed along the moving direction of the moving body, and the outside of the end point of the position information reading section in the moving direction is the non-installation section, and the non-installation section is used as the non-installation section. The method for controlling a moving body according to any one of claims 1 to 6, further comprising connecting to a rail to form a travel path for the moving body. The mobile body is
a coil as the movable element;
a power control unit that controls power supplied to the coil;
a detection unit that detects a power value generated in the coil;
a position estimation unit that estimates the estimated position based on a control value for controlling power supplied to the coil by the power control unit and a power value detected by the detection unit;
The method for controlling a moving body according to any one of claims 1 to 7, comprising: rail and
a moving body that moves along the rail;
a control device;
Equipped with
The said rail is
a stator;
a first installation section in which the position information reading section is installed;
a non-installed section having a section where the position information reading section is not installed;
a second installation section installed between the first installation section and the non-installation section, and in which the position information reading section is installed;
Equipped with
The mobile body is
a mover that generates thrust using magnetic force generated by the stator;
a position information reading unit that reads position information from the position information reading unit;
Equipped with
The control device includes:
In the first installation section, a first control process of controlling movement of the mobile body based on a reading position indicated by the position information read by the position information reading unit from the position information reading unit;
a second control process that performs sensorless vector control of the movement of the mobile body in the non-installation section based on the estimated position of the mobile body;
In the second installation section, the first control process and the second control process are executed while controlling the mobile body based on the reading position and controlling the mobile body based on the estimated position. a switching process that performs switching;
A mobile control system that executes

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