JP6910790B2 - Automatic guided vehicle control system - Google Patents

Description

The present invention relates to an automatic guided vehicle (AGV) control system and an automatic guided vehicle control system that do not require removal and re-installation of derivatives and the like when traveling even if the traveling route is changed. The present invention relates to a method of setting coordinates of a traveling area.

Automatic guided vehicles (AGVs), which automatically transport a predetermined load to a destination without being directly operated by an operator, have been widespread since the 1980s and are widely used mainly at production sites. Further, it is being widely introduced not only at production sites but also in fields other than the manufacturing industry such as distribution centers for storing and shipping products or hospitals (see, for example, Patent Document 1).

In order to realize the automatic traveling of the automatic guided vehicle, a control system for guiding the automatic guided vehicle to the destination is required, and the guidance method constituting the system is, for example, a route scheduled to be traveled. The magnetic induction type using a magnetic tape, a magnetic marker, or the like that is laid and guides the automatic guided vehicle directly to the destination is the mainstream.

In addition, as other guidance methods, a system using some derivative such as a barcode guidance method or a laser guidance method, a self-position estimation method using a gyro sensor or a laser, etc. are known, and introduction is being considered at various sites. (See, for example, Patent Documents 2 and 3).

Japanese Patent No. 4617293 Japanese Unexamined Patent Publication No. 2016-55963 Japanese Unexamined Patent Publication No. 2011-141665

In the system for controlling the automatic guided vehicle using the above-mentioned derivatives, some derivative (guidance line such as magnetic tape, magnetic marker, bar code, reflector, etc.) for guiding the automatic guided vehicle to the destination is used as the transport path. It is necessary to install it on the floor along the floor or on the surrounding walls, but the transportation route at the production site where automatic guided vehicles are introduced is not limited to automatic guided vehicles, but also large forklifts, hand lifts (manual forklifts), etc. Alternatively, an operator or the like frequently passes through the transport path. Therefore, there is a problem that the derivative installed on the floor or the wall surface is gradually worn and damaged, which hinders the running of the automatic guided vehicle. In order to ensure the correct running of the automatic guided vehicle, the derivative is regularly used. Maintenance is indispensable. In addition, when reviewing the production process or changing the layout of the production site, the transport route of the automatic guided vehicle will also change, so after removing the derivative before the layout is changed, a new layout will be created. It is necessary to design a new transport route according to the above, and to re-install the derivative corresponding to the transport route, and there is a problem that it takes a considerable amount of time to change the route of the automatic guided vehicle.

In addition, in the automatic guided vehicle control system based on the gyro guidance method using a gyro sensor, the gyro sensor mounted on the automatic guided vehicle detects changes in the attitude angle of the automatic guided vehicle and integrates the mileage to self-calculate. The position is calculated and controlled to run along the running route set on the computer, but due to the influence of individual differences (running accuracy) of the automatic guided vehicle and minute irregularities on the running surface, the calculation is performed. There is a problem that it is not possible to completely eliminate the deviation between the estimated self-position and the actual position, and it is necessary to periodically confirm and correct the self-position.

Furthermore, as one of the self-position estimation methods, a method of irradiating a laser beam from an automatic guided vehicle to the surroundings and analyzing the reflected light to estimate the self-position and travel has been proposed. Based on this, in order to drive an automatic guided vehicle, it is necessary to perform a sufficient trial run on the planned transport route and create an electronic map on a computer from the information learned by the trial run. There is a problem that it is necessary to recreate the electronic map each time with the change of the above, which is unbearable.

The present invention has been made in view of the above facts, and its main technical problem is that there is no need to install or repair the derivative, and even if there is a change in the route to which the automatic guided vehicle should travel, it is automatic. It is an object of the present invention to provide an automatic guided vehicle control system capable of traveling along a transport route without requiring a large amount of time for resetting a transport route on which the transport vehicle travels.

In order to solve the above-mentioned main technical problem, according to the present invention, an automatic guided vehicle control system for controlling an automatic guided vehicle, the automatic guided vehicle provided with a guide sign recognizing means for recognizing a guide mark, and the automatic guided vehicle. It is composed of at least a control means for controlling automatic traveling, and the control means is based on a coordinate storage unit that stores coordinates with an invariant feature point selected from an environment including a traveling area as a guideline and a coordinate storage unit based on the coordinates. A travel route storage unit that stores a travel route to be set and a destination setting unit that sets a destination to be reached by the automatic guided vehicle based on the travel route are provided, and the guideline constitutes a floor surface. a mesh shape of embedded rebar in concrete to, signpost recognition means the automatic guided vehicle is equipped with the assembled form of reinforcing bars under the floor surface by rebar exploration means, have a variation according to the detected position floor It is detected as a mesh shape showing different characteristics depending on the position in the plane and used as a guide, and the coordinate storage unit previously travels the automatic guided vehicle in the traveling area where the traveling route is set. A plurality of mesh shapes of reinforcing bars embedded under the floor surface are detected in the traveling area by using a reinforcing bar exploration means, and the coordinates of the traveling area set in association with the image information of each mesh shape are stored. The automatic guided vehicle is provided with an automatic guided vehicle control system that recognizes the guideline, travels along a traveling route, and reaches the destination.

The "immutable feature point" of the present invention means that even if it is necessary to change the traveling route on which the automatic guided vehicle travels and set a new traveling route, there is no need to change the traveling route. It shows the feature points in the area.

In the automatic guided vehicle control system of the present invention, the automatic guided vehicle includes a guide recognition means for recognizing a guide, and the control means for controlling the automatic traveling of the automatic guided vehicle is an invariant selected from an environment including a traveling area. A coordinate storage unit that stores coordinates with a feature point as a guide, a travel route storage unit that stores a travel route set based on the coordinates, and a purpose to be reached by the automatic guided vehicle based on the travel route. The guide is provided with a destination setting unit for setting the ground, the guide is a mesh shape of reinforcing bars embedded in concrete constituting the floor surface, and the guide recognition means provided by the automatic guided vehicle is provided by the reinforcing bar exploration means. the assembly forms rebar under floor, there is to be detected to signpost as a network shape showing different characteristics depending on the position in the have a variation according to the detected position the floor, the coordinate storing unit, In the traveling region where the traveling route is set, the automatic guided vehicle is traveled in advance, and a plurality of mesh shapes of reinforcing bars embedded under the floor surface are detected in the traveling region by using the reinforcing bar exploration means, and each of them is detected. It stores the coordinates of the traveling area set in association with the image information of the mesh shape, and the automatic guided vehicle recognizes the guideline and travels along the traveling route to reach the destination. It is not necessary to install a derivative for the automatic guided vehicle to travel in the transport path. For example, if it is applied to a production site, even if the production process is changed or the layout of the site is changed, the derivative of the derivative There is no need to remove or re-lay it, and a new transport route can be easily set, improving production efficiency.

It is a drawing which shows the outline of the automatic guided vehicle applied to the automatic guided vehicle control system of this invention. It is explanatory drawing for demonstrating the function provided by the control means of this invention. It is explanatory drawing for demonstrating the traveling area setting step, the feature point selection step, and the coordinate creation step of this invention. It is explanatory drawing explaining the traveling route set in this embodiment. It is explanatory drawing for demonstrating automatic traveling of the automatic guided vehicle of this invention.

Hereinafter, the automatic guided vehicle control system according to the present invention and the method of setting the coordinates will be described in more detail with reference to the accompanying drawings.

FIG. 1 shows a schematic view of an automatic guided vehicle 10 applied to an automatic guided vehicle control system configured based on the present invention, (a) is a side view, and (b) is a plan view. .. The automatic guided vehicle 10 has, for example, a width of about 1 m and a length of about 1.5 m in the front-rear direction, and is configured to travel on four wheels. It has a rear wheel 11b. As shown in (a) and (b) in the figure, an operation panel 12 for operating the automatic guided vehicle 10 is arranged on the front side of the upper surface 10a, which is a loading surface for loading the transported cargo, and the lower surface 10b. Reinforcing bar exploration means 13a and 13b arranged as the guidepost recognition means of the present invention are arranged on the front side and the rear side of the side. Further, in the center of the lower surface 10b, an antenna 14 for wireless communication with a computer on which a control means provided separately from the automatic guided vehicle 10 is constructed is arranged. A computer 15 for operating various devices provided in the automatic guided vehicle 10 is arranged in the vicinity of the operation panel 12 inside the automatic guided vehicle 10. In addition to these, the automatic guided vehicle 10 is informed that it has approached an automatic steering mechanism for automatically steering the front wheels 11a, a drive motor and a battery for driving the drive wheels 11b, and an obstacle. A proximity sensor, an emergency stop button, and the like for detecting and stopping the automatic guided vehicle 10 are provided, but the general device provided in the automatic guided vehicle 10 is not shown.

The reinforcing bar exploration means 13a and 13b of the automatic guided vehicle 10 will be described more specifically. As described above, the reinforcing bar exploration means 13a and 13b for detecting the assembled form of the reinforcing bars embedded in the floor surface to be traveled are arranged on the front side and the rear side of the lower surface 10b of the automatic guided vehicle 10. It is installed. As the reinforcing bar exploration means 13a and 13b, various methods known as non-destructive inspection means for inspecting the inside of concrete can be adopted, but in the reinforcing bar exploration means 13a and 13b of the present embodiment, the reinforcing bar exploration means 13a and 13b of the present embodiment can be used. For example, a configuration that implements the electromagnetic radar method can be adopted. The automatic guided vehicle 10 of the present invention radiates electromagnetic waves toward the concrete floor surface from the transmitting antennas constituting the reinforcing bar exploration means 13a and 13b while traveling. The electromagnetic waves pass through the concrete constituting the floor surface, are reflected by the reinforcing bars embedded inside the floor surface, return to the concrete surface, and are received by the receiving antennas built in the reinforcing bar exploration means 13a and 13b, respectively. The position of the reinforcing bar can be detected. In addition, the distance to the reflecting object, that is, the depth to the reinforcing bar can be known at the same time from the time from the transmission to the reception. The position information of the reinforcing bars detected by the reinforcing bar inspection means 13a and 13b is transmitted from the antenna 14 at any time and sent to the computer in which the control means is constructed to recognize the assembled form of the reinforcing bars inside the floor surface.

The automatic guided vehicle control system of the present invention includes the control means 20 for controlling the traveling of the automatic guided vehicle 10 described above (see FIG. 2). The control means 20 is composed of, for example, a computer arranged in an office or the like at a production site, and has a central processing unit (CPU) that performs arithmetic processing according to a control program and a read-only memory (ROM) that stores the control program and the like. It is provided with a readable and writable random access memory (RAM) for temporarily storing detected detection values, calculation results, etc., an input interface, and an output interface (details are not shown). The control means 20 includes at least a coordinate storage unit 201, a travel route setting unit 202, a destination setting unit 203, a communication unit 204, and a travel control unit 205, and the operation of the control means 20 will be described in detail. do.

The present invention includes a method in which an invariant feature point included in a traveling area of an automatic guided vehicle is used as a guidepost and coordinates for specifying a position on the traveling area are set based on the signpost. , The method of setting the coordinates will be described.

In the present embodiment, the mesh shape is used as a guidepost as an assembling form of the reinforcing bars embedded in the concrete floor surface in a mesh shape. More specifically, as shown in FIG. 3A, reinforcing bars 21 shown by dotted lines are embedded in a space formed by pouring concrete into the floor surface 2 in a mesh shape at intervals of approximately 20 cm. Since the work of assembling the reinforcing bars 21 is usually performed manually before the concrete is poured, the intervals of the reinforcing bars forming the mesh shape include a considerable variation, and strictly speaking, at any place. However, once the floor surface 2 is formed, the shape of each mesh does not change unless the floor surface 2 is destroyed. Therefore, in the present embodiment, the mesh shape of each place having this variation is detected as the assembling form of the reinforcing bar, this is selected as an invariant feature point, and the coordinates are set based on this mesh shape .

The method of setting the coordinates described above will be described more specifically. In the present embodiment, when the production site is newly constructed, the coordinates are set before the equipment such as the production equipment is brought in, that is, when there is nothing on the floor surface 2. FIG. 3A shows a floor surface 2 (100 m × 100 m) constituting the production site, and the operator can set the coordinates of the area that defines the traveling area of the automatic guided vehicle. A predetermined area of 2 is set on the control means 20 as a traveling area (traveling area setting step). As described above, a reinforcing bar 21 having a diameter of about 1 cm, which is assembled in a mesh shape shown by a dotted line, is embedded inside the floor surface 2 and has a depth of about 15 cm. The position cannot be seen from above.

When the outer edge of the traveling area is determined by the traveling area setting step, the feature point selection step is executed. More specifically, as shown in FIG. 3B, the automatic guided vehicle 10 is operated from the feature point setting start point (the point where the automatic guided vehicle 10 is positioned), and the arrow in the figure. Start in the direction indicated by. At the same time as starting the automatic guided vehicle 10, the reinforcing bar exploration means 13a and 13b irradiate the electromagnetic waves transmitted through the concrete and reflected by the reinforcing bars 21 to receive the reflected electromagnetic waves. By arithmetically processing the electromagnetic waves received in this way, as shown in FIG. 3C, the mesh shape of the reinforcing bar 21 embedded inside the floor surface 2 can be detected. Since this mesh shape already has variation at the installation stage, the mesh shape detected at each place becomes an invariant feature point indicating the detected position. In order to extract such a mesh shape from the entire floor surface 2, the automatic guided vehicle 10 is run on the path indicated by the solid line and the arrow in FIG. 3B, and the detected mesh shape is determined by the control means 20 at any time. Memorize at time intervals. In addition, in FIG. 3B, for convenience of explanation, the route through which the automatic guided vehicle 10 travels and executes the inspection of the reinforcing bar 21 is schematically shown, but the detection widths of the reinforcing bar detecting means 13a and 13b are automatically conveyed. Since the width is approximately 1 m, which is the same as the width of the vehicle 10, it is necessary to travel at least 100 round trips in order to detect the reinforcing bars 21 on the entire floor surface 2. In this way, if the automatic guided vehicle 10 travels on the entire surface of the floor surface 2 forming the traveling region and all the mesh shapes of the reinforcing bars 21 embedded in the traveling region can be detected, the mesh shapes are combined and shown in FIG. A mesh shape of the entire floor surface 2 as shown in 3 (d) is generated (feature point selection step). For convenience of explanation, the mesh shape of the reinforcing bars 21 shown in FIG. 3 is shown with a larger interval than the original dimensional ratio with the floor surface 2, and according to the actual dimensional ratio, it is larger than the illustrated one. It has a fine mesh shape.

If the mesh shape of the entire traveling region is detected by the feature point selection step, the coordinates of the traveling region are created using the plurality of the feature points, that is, each mesh shape as a guidepost. More specifically, the coordinates are created as shown in FIG. 3D on the image information of the mesh shape of the entire floor surface 2 formed in the feature point selection step described above. In the figure, the horizontal direction is the X-axis direction and the vertical direction is the Y-axis direction, and the coordinates of the lower left intersection of the mesh-shaped intersections are the reference of the coordinates (X ₁₁ , Y ₁₁ ). _{Then, coordinates (X 11} , Y ₁₁ ) to (X _qn , Y _mp ) are attached to the intersections of the mesh shapes, and the coordinates are associated with the image information of the mesh shape, and the coordinate information is combined with the image information. It is stored in the storage unit 201 (coordinate creation step). The mesh shape shown in FIG. 3 (c) shows the range shown by the dotted line W in FIG. 3 (d), and the coordinates created by the coordinate creation step are also shown in FIG. 3 (c). .. This completes the coordinate setting method based on the present invention.

When the coordinates are set and the coordinate information associated with the mesh shape formed by the reinforcing bars 21 is stored in the coordinate storage unit 201, the traveling route can be set based on the coordinates. After the above-mentioned coordinates are set, the production equipment and the like configured on the floor surface 2 are carried in and the layout is fixed. When the layout of the production equipment on the floor surface 2 is determined, the travel route R for traveling the automatic guided vehicle 10 is set while avoiding the production equipment. More specifically, as shown in FIG. 4, the operator sets a travel path R on which the automatic guided vehicle 10 travels based on the information of the coordinates. At this time, although omitted in FIG. 4, it is preferable to superimpose the layout of the production equipment on the image of the traveling region and set the traveling route R so as to avoid the production equipment. When the travel route R is set in this way, the information on the travel route R is stored in the travel route setting unit 202 together with the information on the coordinates. In this way, if the coordinates for specifying the position of the floor surface 2 are generated and the traveling path R is set, the automatic guided vehicle 10 can actually travel automatically.

As described above, when the traveling route R is set on the floor surface 2 based on the information of the coordinates and the automatic guided vehicle can travel, the destination to be reached by the automatic guided vehicle by the operator. Is set. The process in which the three automatic guided vehicles 10A, 10B, and 10C automatically travel to the destinations P1, P2, and P3 will be described with reference to FIG.

As shown in FIG. 5A, the automatic guided vehicles 10A to 10C are positioned at a standby position in which luggage such as parts to be transported is stocked when the transport operation is not executed. In this state, the load to be transported is loaded, and when the load is transported, the operator tells the destination setting unit 203 of the control means 20 to the destination P1 for the automatic transfer vehicle 10A and the automatic transfer vehicle. The destination P2 for the 10B and the destination P3 for the automatic guided vehicle 10C are set and stored. Then, each automatic guided vehicle 10A to 10C calculates the shortest route for each destination P1 to P3, and the traveling control unit 205 determines a necessary traveling instruction for each automatic guided vehicle 10A to 10C and communicates with them. Travel instruction information is transmitted via unit 204. The traveling instructions determined by the traveling control unit 205 are traveling speed (including acceleration, deceleration, and stop), forward movement, reverse movement, left turn, right turn, and the like.

Based on the travel instruction determined and transmitted by the travel control unit 205, the automatic guided vehicles 10A to 10C start traveling. At the same time as the running is started, the reinforcing bar detecting means 13a and 13b are operated to transmit the electromagnetic wave to the floor surface 2 and receive the reflected electromagnetic wave, and detect the reinforcing bar embedded in the floor surface 2. When the detection is carried out, the mesh shape of the reinforcing bar inside the floor surface 2 as shown in FIG. 3C is detected. As described above, the mesh shape varies in its interval at the time of installation, and the shape differs depending on the detection location. Therefore, if the mesh shape formed by the reinforcing bars 21 embedded in the floor surface 2 at the current position is detected, the image recognition process is executed to determine which position of the mesh shape is stored in the coordinate storage unit. The images are collated to see if they match, and the current position and direction of each automatic guided vehicle 10A to 10C are specified on the coordinates. By repeating such processing at predetermined time intervals (for example, every 0.1 seconds), the vehicle travels from the travel control unit 205 while always checking which position on the transport route calculated as the shortest route. The instruction is transmitted, and the vehicle continues traveling toward the destinations P1 to P3 (see FIG. 5B). Then, when approaching the destinations P1 to P3, the vehicle gradually decelerates, stops at the destinations P1 to P3, and the workers at the destinations P1 to P3 carry in the transported luggage. , The worker gives an instruction to complete the delivery to each of the automatic guided vehicles 10A to 10C. Each of the automatic guided vehicles 10A to 10C for which the carry-in completion instruction has been given resumes traveling toward the next destination if there is a next destination, and returns to the above-mentioned standby position if there is no instruction for the destination. do.

As described above, the automatic guided vehicles 10A to 10C in the present embodiment recognize the mesh shape formed by the reinforcing bars 21 embedded in the floor surface 2 as a guidepost, and use the coordinates defined based on the mesh shape. The position and direction on the floor surface 2 are specified, and the vehicle travels to the destination based on the coordinates. The position of the reinforcing bar 21 in the floor surface 2 is an immutable feature point that does not change unless the floor surface is destroyed. Alternatively, no matter how much the worker passes by, there is no risk of wear or damage, and even if the surface on the floor surface 2 is slightly damaged, or if paint or the like is applied to change the pattern. Not affected. Therefore, even if the layout of the production equipment installed on the floor surface 2 is changed, there is no need to remove or re-install the derivative, and there is no need to repeatedly carry out the coordinate creation step, resulting in a new layout. After that, it is possible to reset a new travel route R for traveling the automatic guided vehicle simply by setting the travel route R by the control means 20 based on the coordinates based on the mesh shape of the reinforcing bar 21 already stored. can. Since the reinforcing bar inspection means 13a and 13b are arranged in front of and behind the automatic guided vehicle 10, the recognition accuracy of the current position including the orientation of the automatic guided vehicle can be improved as compared with the case of detecting at one location. Can be improved.

Further, when a plurality of automatic guided vehicles 10A to 10C are driven, a detour can be set if necessary by notifying each other of the positions of the automatic guided vehicles by wireless communication. Further, in the present embodiment, the traveling control unit 205 is constructed in the control means 20 on a computer arranged separately from the automatic guided vehicle, but the present invention is not limited to this. The function of the control means 20 described above can also be built on the computer 15 loaded on the automatic guided vehicles 10A to 10C. That is, the coordinate information of the floor surface 2 created in the coordinate creation step described above is stored in the computer 15 of the automatic guided vehicles 10A to 10C. Then, a running instruction calculated based on the current position information recognized by the automatic guided vehicles 10A to 10C is given from the computer 15 mounted on the automatic guided vehicles 10A to 10C. By doing so, even if the number of automatic guided vehicles traveling on the floor surface 2 increases, the computing load of the computer that manages a plurality of automatic guided vehicles at the same time does not become excessive, and the traveling route can be smoothly routed. It can be run. In this way, since the automatic guided vehicle itself can run completely on its own, it is possible to obtain the effect that the luggage can be carried without relying on wireless communication from the start of running to the arrival at the destination.

In the present embodiment, as a means for detecting the reinforcing bars in the concrete which is mounted on the automatic transport vehicle and constitutes the floor surface, an electromagnetic laser method for irradiating an electromagnetic wave to detect the position thereof has been carried out, but the present invention is limited to this. Instead, the floor can be detected by irradiating the floor surface with X-rays to detect the internal reinforcing bars, or by positioning the reinforcing bars, which are the objects to be detected, in the magnetic field created by passing an AC current through the detection coil. Various methods used in non-destructive inspections for detecting the arrangement of reinforcing bars in concrete, such as a method for detecting reinforcing bars inside a surface, can be adopted.

2: Floor surface 10, 10A, 10B, 10C: Automatic guided vehicle 10a: Upper surface 10b: Lower surface 11a: Front wheel 11b: Rear wheel 12: Operation panel 13a, 13b: Reinforcing bar detecting means (signpost recognition means)
14: Antenna 15: Computer 20: Control means 21: Reinforcing bar R: Travel path

Claims (1)

It is an automatic guided vehicle control system that controls automatic guided vehicles.
It is composed of at least an automatic guided vehicle provided with a signpost recognition means for recognizing a signpost and a control means for controlling the automatic traveling of the automatic guided vehicle.
The control means includes a coordinate storage unit that stores coordinates with an invariant feature point selected from an environment including a travel area as a guidepost, and a travel route storage unit that stores a travel route set based on the coordinates. A destination setting unit that sets a destination to be reached by the automatic transport vehicle based on the travel route.
The signpost has a mesh shape of reinforcing bars embedded in the concrete constituting the floor surface.
The signpost recognition means automatic guided vehicle is equipped with the detecting assembly forms rebar under the floor by rebar exploration means, as a network shape showing different characteristics depending on the position of the chromatic and the floor variations according to the detected position And use it as a guidepost
The coordinate storage unit travels the automatic guided vehicle in advance in the traveling area where the traveling route is set, and uses the reinforcing bar exploration means to form a mesh shape of the reinforcing bars embedded under the floor surface in the traveling area. Multiple detection is performed, and the coordinates of the traveling area set in association with the image information of each mesh shape are stored.
The automatic guided vehicle is an automatic guided vehicle control system that recognizes the signpost, travels on a traveling route, and reaches the destination.

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