WO2022145142A1 - Cargo handling vehicle system - Google Patents

Abstract

This cargo handling vehicle system comprises a control command generation unit (220) that controls a cargo handling vehicle according to a plant model, a travel route generation unit (206) that creates a travel route for the cargo handling vehicle, a nearest node calculation unit (215), a work determination unit (230), and a plant model switching unit (231). The travel route is constructed from a plurality of nodes provided with work IDs indicating work to be implemented by the cargo handling vehicle. The nearest node calculation unit (215) determines a current node that is in the position nearest to the position of the cargo handling vehicle, and a target node through which the cargo handling vehicle should pass after the current node. The work determination unit (230) compares the work IDs of the current node and the target node. The plant model switching unit (231) switches the plant model to a plant model corresponding to the work identified by the work ID of the target node when the work IDs of the current node and the target node are mutually different.

Description

Cargo handling vehicle system

The present invention relates to a cargo handling vehicle system that controls a cargo handling vehicle.

In recent years, with the labor shortage due to the declining birthrate and aging population and the increase in the number of logistics due to the expansion of the e-commerce market, labor saving and improvement of work efficiency in the logistics warehouse have become issues. In order to solve this problem, the introduction of unmanned industrial vehicles that can operate unmanned is being promoted.

A material handling vehicle such as a forklift is used for transporting cargo in the warehouse. In an automatic guided vehicle using a cargo handling vehicle, a cargo handling operation in which the tip of a cargo handling member (fork) is inserted into the opening of a pallet (loading platform) on which the load is placed and lifted, or the load loaded on the cargo handling member is moved to a predetermined position. It is necessary to automatically carry out a series of operations such as loading and unloading operations for letting and unloading and pulling out cargo handling members.

In order to safely and efficiently and automatically carry out the cargo transportation work using the material handling vehicle as described above, a traveling control technology that enables autonomous control of the material handling vehicle is required. One of the travel control techniques is a route tracking function for a cargo handling vehicle to autonomously travel according to a target route. In order to construct the route tracking function, generally, a plant model of the vehicle to be controlled (a model showing the operating characteristics of the vehicle to be controlled) is created based on the geometric conditions of the vehicle structure. After that, for example, a feedback control model that minimizes the difference between the target path and the self-position is constructed, and each parameter of the plant model and the feedback control model is tuned to realize a highly accurate path tracking function.

Cargo handling vehicles such as forklifts not only run and stop, but also turn on the spot (spin turn), lift and lower the transfer device (device that raises and lowers the cargo handling member) accompanying loading and unloading movements, and front and rear of the cargo handling member. Perform multiple tasks such as moving. In addition, the cargo handling vehicle performs a traveling operation according to the presence or absence of a load and a traveling operation (reverse travel) such that the cargo handling member is located behind in the traveling direction in order to prevent the cargo from falling during traveling. There are various driving modes in.

When driving a vehicle having a wide variety of driving modes as described above, it is extremely difficult to construct an accurate plant model and feedback control model corresponding to all the work to be performed.

For such a problem, for example, the invention described in Patent Document 1 has been proposed. The industrial vehicle (forklift) described in Patent Document 1 is provided with a plurality of driving modes according to the work and a plant model corresponding to the driving mode, and the forklift driver manually switches the driving mode according to the work to be performed. ..

JP-A-2017-226514

In the conventional technique such as the invention described in Patent Document 1, a worker such as a forklift driver manually switches the traveling mode according to the work to be performed, thereby switching the plant model. In a cargo handling vehicle that performs autonomous control, it is necessary to automatically perform operations such as traveling, loading, unloading, and in-situ turning, and for this purpose, it is also necessary to automatically switch plant models. be.

An object of the present invention is to provide a cargo handling vehicle system capable of automatically switching plant models.

The cargo handling vehicle system according to the present invention includes a cargo handling member on which a cargo carried by a cargo handling vehicle is placed, a control command generation unit, a travel route generation unit, a nearest neighbor node calculation unit, a work determination unit, and a plant model switching unit. And. The control command generation unit controls the cargo handling vehicle according to a plant model showing operating characteristics when the cargo handling vehicle performs work. The travel route generation unit creates a travel route for the cargo handling vehicle. The traveling route is composed of a plurality of nodes indicating a position through which the cargo handling vehicle passes, and one or more links connecting the two nodes. Each of the nodes is provided with a work ID indicating the work to be performed by the cargo handling vehicle. The nearest node calculation unit inputs the position of the cargo handling vehicle and the travel route, and among the nodes constituting the travel route, finds the node closest to the position of the cargo handling vehicle as the current node. Among the nodes constituting the traveling route, a target node, which is a node to be passed by the cargo handling vehicle next to the current node, is obtained. The work determination unit compares the work ID at the current node with the work ID at the target node. When the work ID at the current node and the work ID at the target node are different from each other, the plant model switching unit responds to the work specified by the work ID at the target node with the plant model. Switch to the plant model.

According to the present invention, it is possible to provide a cargo handling vehicle system capable of automatically switching plant models.

It is a figure which shows the cargo handling vehicle controlled by the cargo handling vehicle system by Embodiment 1 of this invention. It is a functional block diagram which shows the structure of the cargo handling vehicle system by Embodiment 1. FIG. It is a figure which shows the outline of the route information of a cargo handling vehicle. It is a figure which shows the work performed by a cargo handling vehicle for each work ID. It is a flowchart which shows the process flow of a work determination part and a plant model switching part. It is a flowchart which shows the flow of another process of a work determination part and a plant model switching part. It is a conceptual diagram which shows the cargo handling vehicle when switching a plant model. It is a figure which shows the transfer function of a traveling motor. It is a figure which shows the example of the relationship between the command value and the response value of a traveling motor. It is a figure which shows the transfer function of a steering motor. It is a figure which shows the example of the relationship between the command value and the response value of a steering motor. It is a figure which shows the cargo handling vehicle which carries out forward running (rear wheel drive). It is a figure which shows the cargo handling vehicle which runs backward (front wheel drive). It is a functional block diagram which shows the structure of the cargo handling vehicle system by Example 2 of this invention. In Example 2, it is a figure which shows the transfer function which shows the responsiveness of a steering motor. It is a figure which shows the feedforward control using the transfer function which shows the responsiveness of the steering motor obtained by the learning part in Example 2. FIG.

The cargo handling vehicle system according to the present invention can automatically switch the plant model for controlling the cargo handling vehicle according to the work of the cargo handling vehicle. The cargo handling vehicle system according to the present invention automatically acquires, for example, the work to be executed from the information of the traveling route, and automatically switches the plant model based on the acquired work to be executed. Further, the cargo handling vehicle system according to the present invention may be provided with a configuration in which data (learning data) for improving the accuracy of the plant model is automatically generated for each work.

The plant model is a model that shows the operating characteristics when a cargo handling vehicle performs work, and is also called a vehicle model. The plant model is represented by a transfer function or an equation of motion, as will be described later.

Since the cargo handling vehicle system according to the present invention automatically switches the plant model according to the work to be performed, highly accurate traveling control is possible and the transportation operation efficiency of the cargo handling vehicle can be improved. In addition, since the plant model is switched for each work, restrictions on the passage through which the cargo handling vehicle travels can be reduced, and the layout in the warehouse for storing the cargo to be loaded on the cargo handling vehicle can be optimized. Further, if the cargo handling vehicle system according to the present invention is provided with a configuration in which data for improving the accuracy of the plant model is automatically generated for each work, a tuningless control system can be constructed, so that the engineering cost at the time of system introduction can be reduced. Can be reduced.

Hereinafter, the cargo handling vehicle system according to the embodiment of the present invention will be described. In the embodiment described below, the cargo handling vehicle controlled by the cargo handling vehicle system is a cargo handling vehicle capable of unmanned operation and autonomous control for automatically performing work, for example, a forklift traveling in a warehouse. Is.

In the drawings used in the present specification, the same or corresponding components may be designated by the same reference numerals, and repeated description of these components may be omitted.

The cargo handling vehicle system according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 10.

First, the cargo handling vehicle controlled by the cargo handling vehicle system according to this embodiment will be described.

(Cargo handling vehicle 100)
FIG. 1 is a diagram showing a cargo handling vehicle 100 controlled by the cargo handling vehicle system according to the present embodiment. The cargo handling vehicle 100 can be autonomously controlled and carries a load.

The cargo handling vehicle 100 includes a vehicle frame 101, a transfer device 102 provided on the vehicle frame 101 so as to be able to move up and down, and a cargo handling member 103 capable of moving in and out of the transfer device 102 to load a load. For example, the cargo handling vehicle 100 is a forklift traveling in a warehouse, and the cargo handling member 103 is a fork. In FIG. 1, the raised transfer device 102 and the cargo handling member 103 are shown by broken lines.

The cargo handling vehicle 100 is equipped with an outside world sensor 104 that acquires position information of objects around the cargo handling vehicle 100. The outside world sensor 104 is installed, for example, on the upper part of the vehicle frame 101. The cargo handling vehicle 100 may be equipped with one or a plurality of external world sensors 104. The outside world sensor 104 is, for example, a LiDAR (Light Detection and Ringing) device, and changes the irradiation direction of the laser beam at predetermined angles (for example, every 0.5 degree) to surround the cargo handling vehicle 100. The position information and shape information of the object are detected as a point cloud.

The cargo handling vehicle 100 is equipped with an acceleration sensor 105 that acquires the acceleration when the vehicle body travels. The acceleration sensor 105 can also acquire the angular velocity when the vehicle body of the cargo handling vehicle 100 turns. The acceleration sensor 105 is installed, for example, on the side surface of the vehicle frame 101. The cargo handling vehicle 100 may be equipped with one or a plurality of acceleration sensors 105.

In the cargo handling vehicle 100, a load sensor 106 for acquiring the mass of the cargo is installed on the cargo handling member 103. The load sensor 106 is, for example, a pressure sensor. The cargo handling vehicle 100 can be equipped with one or a plurality of load sensors 106. For example, in the cargo handling vehicle 100, a plurality of load sensors 106 arranged in the front-rear direction of the cargo handling member 103 and an inclination sensor for detecting the inclination angle of the cargo handling member 103 are installed, and the position of the center of gravity in the vertical direction of the load is more accurately determined. May be provided with the configuration required for.

The cargo handling vehicle 100 is equipped with an in-vehicle controller 107 that performs an operation for autonomously controlling the cargo handling vehicle 100. The in-vehicle controller 107 is installed, for example, on the upper surface of the vehicle frame 101. One or a plurality of vehicle-mounted controllers 107 are installed in the cargo handling vehicle 100. For example, in the cargo handling vehicle 100, a plurality of vehicle-mounted controllers 107 may be installed, and the vehicle-mounted controllers 107 may perform different processes from each other.

(Cargo handling vehicle system 200)
FIG. 2 is a functional block diagram showing the configuration of the cargo handling vehicle system 200 according to the present embodiment. The cargo handling vehicle system 200 controls a cargo handling vehicle 100 capable of autonomous control. The cargo handling vehicle system 200 can control one or more cargo handling vehicles 100. In FIG. 2, the solid line with an arrow represents the flow of data with an arrow.

The cargo handling vehicle system 200 includes a traffic control unit 201 and an in-vehicle controller 107 installed in the cargo handling vehicle 100. The traffic control unit 201 includes a communication device 203. The in-vehicle controller 107 includes a communication device 202. The traffic control unit 201 and the vehicle-mounted controller 107 are connected to each other and communicate with each other via the respective communication devices 203 and 202. The traffic control unit 201 and the vehicle-mounted controller 107 can transmit and receive necessary data to and from each other by using a wireless network or the like.

Further, the cargo handling vehicle system 200 includes an outside world sensor 104, an acceleration sensor 105, and a load sensor 106 installed in the cargo handling vehicle 100. The vehicle-mounted controller 107 is connected to the external world sensor 104, the acceleration sensor 105, and the load sensor 106, and inputs the information acquired by these sensors.

The in-vehicle controller 107 includes a plant model switching unit 231 described later, and the plant model switching unit 231 automatically switches the plant model according to the work to be performed.

The traffic control unit 201 and the vehicle-mounted controller 107 include processors such as a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit) for performing operations for controlling the cargo handling vehicle 100, and a memory for storing programs and data. It can be configured with a computer.

(Traffic Control Department 201)
First, the traffic control unit 201 will be described. The traffic control unit 201 includes an operation management unit 204, a route map management unit 205, a travel route generation unit 206, a plant model management unit 232, and the communication device 203 described above, and manages the operation of the cargo handling vehicle 100.

(Operation Management Department 204)
The operation management unit 204 determines a task command to be executed by the cargo handling vehicle 100, and outputs the task command to the travel route generation unit 206. A plurality of task commands that determine which cargo is to be transported from where to where are stored in advance in the operation management unit 204. The operation management unit 204 assigns these task commands to a plurality of cargo handling vehicles 100, and determines the task commands to be executed by each cargo handling vehicle 100. For example, the operation management unit 204 can assign a task command to the cargo handling vehicle 100 according to the position of the cargo handling vehicle 100.

(Route Map Management Department 205)
The route map management unit 205 stores the data of the two-dimensional map of the range in which the cargo handling vehicle 100 travels. Information (route information) about the route on which the cargo handling vehicle 100 can travel is given to this two-dimensional map by the operator of the cargo handling vehicle system 200. The two-dimensional map is, for example, a map of the entire warehouse in which the cargo handling vehicle 100 travels. For example, the route map management unit 205 can input the point cloud data acquired by the outside world sensor 104 while the cargo handling vehicle 100 is traveling, and create a two-dimensional map in advance using SLAM (Simultaneus Localization and Mapping).

FIG. 3 is a diagram showing an outline of route information of the cargo handling vehicle 100. FIG. 3 shows, as an example, a route in which the cargo handling vehicle 100 approaches the shelves 307 and the pallets 304 on which the cargo is placed. A reference coordinate system 310 is set in the two-dimensional map stored by the route map management unit 205. In FIG. 3, the reference coordinate system 310 is represented by the _XG axis and the _YG axis.

The route information is composed of a plurality of traveling nodes 301 and 302 indicating a position through which the cargo handling vehicle 100 passes, and one or more links 303 connecting the two traveling nodes 301 and 302. One link 303 or a plurality of links 303 connected to each other constitutes segment 305. The route information is composed of one or more segments 305. The traveling node located at the end of the segment 305 (the end of the route) is the end node 306.

Each of the traveling nodes 301 and 302 has data such as a target position, a target posture, a target speed, and a turning radius R with respect to the reference coordinate system 310 for the cargo handling vehicle 100. The target position, target posture, and target speed are the positions, postures, and speeds that the cargo handling vehicle 100 should take at the traveling nodes 301 and 302, respectively. The turning radius R is a radius to be taken when the cargo handling vehicle 100 turns at the traveling nodes 301 and 302, respectively. These data are added to the two-dimensional map by the operator of the cargo handling vehicle system 200 as route information.

The posture of the cargo handling vehicle 100 is the yaw angle (azimuth angle) of the vehicle body of the cargo handling vehicle 100 with respect to the reference coordinate system 310.

The current position of the cargo handling vehicle 100 is called the self-position 311, and the current posture of the cargo handling vehicle 100 is called the self-position 312. In FIG. 3, the self-posture 312 of the cargo handling vehicle 100 is represented by the angle of the cargo handling vehicle 100 in the front-rear direction _YV with respect to the _YG axis (equal to the angle of the cargo handling vehicle 100 in the lateral direction _XV with respect to the _XG axis).

In addition, a work ID is preset in the route map management unit 205. The work ID indicates the work performed by the cargo handling vehicle 100. The work ID is provided in each of the traveling nodes 301 and 302 in the route information stored by the route map management unit 205. The work to be performed by the cargo handling vehicle 100 at the traveling nodes 301 and 302, respectively, is specified by the work ID. One traveling node can include a plurality of work IDs.

FIG. 4 is a diagram showing the work performed by the cargo handling vehicle 100 for each work ID. The work carried out by the cargo handling vehicle 100 includes, for example, straight line running (running in which the turning radius R is larger than the predetermined radius R0), turning running (running in which the turning radius R is less than or equal to the radius R0), and spin turn (running in which the turning radius R is equal to or less than the radius R0). There are on-the-spot turns without moving) and cargo handling. The radius R0 can be arbitrarily determined in advance and is, for example, 360 m. Further, in the work performed by the cargo handling vehicle 100, for example, a moving direction, a turning direction, a type of cargo handling (loading operation or unloading operation), and the like are defined as subtasks. Further, the work to be performed by the cargo handling vehicle 100 is also specified by the work ID depending on whether or not the cargo handling vehicle 100 is loaded with cargo (presence or absence of cargo).

Returning to FIG. 2, the explanation of the traffic control unit 201 is continued.

(Traveling route generation unit 206)
The travel route generation unit 206 inputs a task command to be executed by the cargo handling vehicle 100 from the operation management unit 204, and inputs route information from the route map management unit 205 to drive the cargo handling vehicle 100 for executing the task command. Create a route. The travel route generation unit 206 can create a travel route for the cargo handling vehicle 100 by using the existing technique. The travel route created by the travel route generation unit 206 is, for example, as shown in FIG. 3, one or more links connecting a plurality of travel nodes 301, 302 including the terminal node 306 and the two travel nodes 301, 302. It is composed of 303. As described above, the traveling nodes 301 and 302 are provided with work IDs.

The travel route generation unit 206 transmits the travel route of the created cargo handling vehicle 100 to the self-position / posture calculation unit 214 of the vehicle-mounted controller 107 via the communication device 203 of the traffic control unit 201 and the communication device 202 of the vehicle-mounted controller 107. ..

The plant model management unit 232 will be described later.

(In-vehicle controller 107)
Subsequently, the vehicle-mounted controller 107 will be described. The in-vehicle controller 107 includes a self-position attitude calculation unit 214, a nearest node calculation unit 215, a load load calculation unit 216, a vehicle body behavior calculation unit 217, a control command generation unit 220, a steering motor drive unit 221 and a traveling motor drive unit 222, and a brake. A drive unit 223, a transfer device / cargo handling member motor drive unit 224, a work determination unit 230, a plant model switching unit 231 and the above-mentioned communication device 202 are provided, and calculations are performed using these elements.

(Self-position / posture calculation unit 214)
The self-position / attitude calculation unit 214 uses the information of the point cloud about the object around the cargo handling vehicle 100 acquired by the outside world sensor 104 and the data of the two-dimensional map provided in the route map management unit 205 to be used in the reference coordinate system 310. The self-position 311 and the self-position 312 (FIG. 3) of the cargo handling vehicle 100 are acquired. The self-position attitude calculation unit 214 transmits the acquired self-position 311 and self-posture 312 to the nearest node calculation unit 215. Further, the self-position / attitude calculation unit 214 transmits the travel route of the cargo handling vehicle 100 received from the traffic control unit 201 to the nearest node calculation unit 215.

The self-position / posture calculation unit 214 may acquire the self-position 311 and the self-posture 312 of the cargo handling vehicle 100 by using other means. For example, the self-position / attitude calculation unit 214 uses information such as the angular velocity of the cargo handling vehicle 100 during turning, the rotation speed of the wheels of the cargo handling vehicle 100, and the radius of the wheels detected by the acceleration sensor 105 in combination to achieve higher accuracy. The position 311 and the self-position 312 may be obtained. The rotation speed of the wheels of the cargo handling vehicle 100 can be detected by an encoder installed in the cargo handling vehicle 100.

(Nearest Neighbor Node Calculation Unit 215)
The nearest neighbor node calculation unit 215 calculates the travel node closest to the self-position 311 of the cargo handling vehicle 100 as the nearest neighbor node among the travel node group constituting the travel path of the cargo handling vehicle 100. As described above, the travel route of the cargo handling vehicle 100 is created by the travel route generation unit 206 of the traffic control unit 201. As described above, the self-position attitude calculation unit 214 acquires the self-position 311 of the cargo handling vehicle 100.

The nearest neighbor node calculation unit 215 inputs the self-position 311 and the travel route of the cargo handling vehicle 100, and calculates the distance difference between the travel node group constituting the travel route and the self-position 311 to calculate the distance difference between the self-position 311 and the nearest neighbor of the cargo handling vehicle 100. Find the node. The nearest node of the cargo handling vehicle 100 is called a "current node". In the example shown in FIG. 3, the traveling node 301 is the current node.

Further, among the traveling node group constituting the traveling route of the cargo handling vehicle 100, the traveling node (traveling node 302 in FIG. 3) to which the cargo handling vehicle 100 should pass next to the current node (traveling node 301 in FIG. 3) is referred to as "traveling node 302". Called the "target node". The target node is a traveling node (traveling node 302 in FIG. 3) other than the current node of the link 303 existing in the traveling direction of the cargo handling vehicle 100 among the links connected to the current node (traveling node 301). The link 303 connecting the current node (traveling node 301) and the target node (traveling node 302) is referred to as a "target link". In the target link (link 303), the direction from the current node (traveling node 301) toward the target node (traveling node 302) is referred to as a "target traveling direction".

The nearest node calculation unit 215 obtains the current node 301, the target node 302, and the target link 303, and generates a control command for the information of the current node 301, the target node 302, and the target link 303 and the information defined therein. It is transmitted to the unit 220 and the work determination unit 230. The nearest neighbor node calculation unit 215 also transmits the work ID provided in the current node 301 and the target node 302 and the self-position 311 of the cargo handling vehicle 100 to the control command generation unit 220 and the work determination unit 230.

(Load capacity calculation unit 216)
The load load calculation unit 216 acquires the mass of the load using the load sensor 106. The load load calculation unit 216 transmits the acquired mass of the load to the work determination unit 230 and the control command generation unit 220.

(Vehicle behavior calculation unit 217)
The vehicle body behavior calculation unit 217 acquires the acceleration of the vehicle body when the cargo handling vehicle 100 travels by using the acceleration sensor 105. The vehicle body behavior calculation unit 217 transmits the acquired acceleration to the work determination unit 230 and the control command generation unit 220.

(Control command generator 220)
The control command generation unit 220 inputs information as described below, for example, and controls the cargo handling vehicle 100 according to the plant model using the input information.

The control command generation unit 220 inputs a target speed defined in the target node 302, and controls the cargo handling vehicle 100 so as to travel at this target speed. For example, when the cargo handling vehicle 100 travels by a motor, the control command generation unit 220 generates a command value for the traveling motor of the drive wheel of the cargo handling vehicle 100, and feeds back the difference between the current command value and the response value of the traveling motor. Then, control is performed to reduce this difference.

Further, the control command generation unit 220 inputs the target traveling direction defined in the target link 303, and controls the cargo handling vehicle 100 so as to travel along the target traveling direction. For example, the control command generation unit 220 generates a command value for the steering motor of the cargo handling vehicle 100, feeds back the difference between the current command value and the response value of the steering motor, and performs control to reduce this difference.

Further, the control command generation unit 220 inputs a work ID provided in the target node 302, and the work specified by the work ID includes, for example, a stop of traveling of the cargo handling vehicle 100 at the target node 302. Generates a brake command for the cargo handling vehicle 100.

Further, the control command generation unit 220 inputs a work ID provided in the target node 302, and when the work specified by the work ID includes, for example, a loading operation of the cargo handling vehicle 100 at the target node 302. Generates a command for raising and lowering the transfer device 102 and a command for moving the cargo handling member 103 in the front-rear direction so that the tip of the cargo handling member 103 can be inserted into the opening of the pallet 304 on which the target load is placed. ..

The control command generation unit 220 outputs the generated command value and command to the drive units 221 to 224 described below.

(Steering motor drive unit 221)
The steering motor drive unit 221 drives a motor (steering motor) that transmits power to the steering wheels of the cargo handling vehicle 100 according to a command value input from the control command generation unit 220.

(Traveling motor drive unit 222)
The traveling motor driving unit 222 drives a motor (traveling motor) that transmits power to the drive wheels of the cargo handling vehicle 100 according to a command value input from the control command generation unit 220.

(Brake drive unit 223)
The brake drive unit 223 drives a motor that transmits power to the hydraulic pump that drives the brake pads in accordance with a brake command input from the control command generation unit 220 in order to stop the rotation of the drive wheels included in the cargo handling vehicle 100. The drive wheels of the cargo handling vehicle 100 stop rotating when the hydraulic pump operates and the brake pads are pressed against the drive wheels.

(Transfer device / cargo handling member motor drive unit 224)
The transfer device / cargo handling member motor drive unit 224 is a control command generation unit 220 that transmits power to a hydraulic pump that drives each of the transfer device 102 and the cargo handling member 103 included in the cargo handling vehicle 100. It is driven according to the command input from. The transfer device 102 moves up and down by operating the hydraulic pump that drives the transfer device 102. The cargo handling member 103 moves in the front-rear direction by operating the hydraulic pump that drives the cargo handling member 103.

(Outline of work determination unit 230)
The work determination unit 230 determines the work performed by the cargo handling vehicle 100 at the target node 302. Hereinafter, the processing of the work determination unit 230 will be briefly described. Details of the processing of the work determination unit 230 will be described later.

The work determination unit 230 compares the work IDs of the current node 301 and the target node 302 obtained by the nearest node calculation unit 215 with each other. Currently, the node 301 and the target node 302 may be given a plurality of work IDs. In this case, the work determination unit 230 selects and compares one work ID according to the state of the cargo handling vehicle 100 (for example, the presence or absence of a load).

The work determination unit 230 determines whether or not the work ID in the target node 302 is different from the work ID in the current node 301. When the work ID in the target node 302 is different from the work ID in the current node 301, the work determination unit 230 assigns a plant model for controlling the cargo handling vehicle 100 to the work specified by the work ID in the target node 302. The plant model switching unit 231 is requested to switch to the corresponding plant model.

Further, in the work determination unit 230, when the work ID in the target node 302 is different from the work ID in the current node 301 and is a work ID preset in the route map management unit 205 of the traffic control unit 201, the work determination unit 230 has a work ID. It is also possible to request the plant model switching unit 231 to switch the plant model for controlling the cargo handling vehicle 100 to the plant model corresponding to the work specified by the work ID at the target node 302. The work ID in the target node 302 is a work ID preset in the route map management unit 205, that is, the work ID in the target node 302 is prepared for the traveling node 302 in the route information stored in the route map management unit 205. It means that it is a work ID that has been created.

(Outline of plant model switching unit 231)
The plant model switching unit 231 switches the plant model for controlling the cargo handling vehicle 100. The plant model switching unit 231 switches the plant model to the plant model corresponding to the work specified by the work ID in the target node 302 in response to the request from the work determination unit 230, and switches the switched plant model to the control command generation unit. Output to 220. Details of the processing of the plant model switching unit 231 will be described later.

(Outline of Plant Model Management Department 232)
Here, the plant model management unit 232 of the traffic control unit 201 will be briefly described. Details of the processing of the plant model management unit 232 will be described later.

The plant model management unit 232 stores the plant model in advance for each work ID shown in FIG. The plant model management unit 232 outputs a plant model (that is, a plant model corresponding to the work specified by the work ID in the target node 302) in response to the request from the plant model switching unit 231 to the plant model switching unit 231.

Hereinafter, the details of the processing of the work determination unit 230 of the in-vehicle controller 107, the plant model switching unit 231 and the plant model management unit 232 of the traffic control unit 201 will be described.

First, the details of the processing of the work determination unit 230 and the plant model switching unit 231 will be described.

(Details of work determination unit 230 and plant model switching unit 231)
FIG. 5A is a flowchart showing a processing flow of the work determination unit 230 and the plant model switching unit 231. The work determination unit 230 and the plant model switching unit 231 perform the processing shown in FIG. 5A after the cargo handling vehicle 100 currently performs the work at the node 301 (nearest neighbor node) and before the work is performed at the target node 302. The work determination unit 230 acquires the work performed by the cargo handling vehicle 100 at the target node 302 (work ID at the target node 302), and determines whether or not it is necessary to switch the plant model for controlling the cargo handling vehicle 100. The plant model switching unit 231 switches the plant model of the cargo handling vehicle 100 in response to a request from the work determination unit 230.

In the process 501, the work determination unit 230 acquires the current node 301 and the target node 302 of the cargo handling vehicle 100 obtained by the nearest node calculation unit 215 from the nearest node calculation unit 215.

In process 502, the work determination unit 230 acquires the state of the cargo handling vehicle 100. The state of the cargo handling vehicle 100 is, for example, whether or not the cargo handling vehicle 100 is loaded with cargo (presence or absence of cargo) and the posture of the cargo handling vehicle 100. For example, the work determination unit 230 acquires the mass of the current load of the cargo handling vehicle 100 from the load calculation unit 216, and determines whether or not the cargo handling vehicle 100 is loaded based on the acquired mass of the load. When the work determination unit 230 determines that the cargo handling vehicle 100 is loaded with a load, the work determination unit 230 obtains the mass of the load. Although the work determination unit 230 depends on the accuracy of the load sensor 106, for example, if the mass acquired from the load calculation unit 216 is less than 10 kg, the cargo handling vehicle 100 does not carry a load (no load). to decide.

In process 503, the work determination unit 230 compares the work IDs (FIG. 4) of the current node 301 and the target node 302 with each other. The work ID at the current node 301 is a work ID that identifies the work currently performed by the cargo handling vehicle 100 at the node 301. When a plurality of work IDs are given to the target node 302, the work determination unit 230 has one, depending on the state of the cargo handling vehicle 100 acquired in the process 502 (for example, the presence or absence of cargo of the cargo handling vehicle 100). A work ID is selected, and the selected work ID is set as the work ID in the target node 302.

If the work ID at the current node 301 and the work ID at the target node 302 are different from each other, the process proceeds to process 504. If these work IDs are the same as each other, the process ends.

In the process 504, the work determination unit 230 determines whether or not the distance Lv from the current position (self-position 311) of the cargo handling vehicle 100 to the target node 302 is equal to or less than the predetermined distance L. The distance L is a threshold value indicating whether or not the distance to the traveling node of the cargo handling vehicle 100 is large, that is, whether or not the cargo handling vehicle 100 has reached the traveling node, and can be arbitrarily determined in advance. When the distance Lv is equal to or less than the distance L, it means that the distance to the traveling node of the cargo handling vehicle 100 is small and the cargo handling vehicle 100 has reached the traveling node. The distance L may be different for each work ID and traveling node.

When the distance Lv is less than or equal to the distance L, the cargo handling vehicle 100 has reached the target node 302, so the process proceeds to the process 505. When the distance Lv is larger than the distance L, the cargo handling vehicle 100 has not reached the target node 302, so the process ends.

In the process 505, the work determination unit 230 determines that the cargo handling vehicle 100 has reached the target node 302 (Lv ≦ L), and therefore the plant model for controlling the cargo handling vehicle 100 is switched.

FIG. 6 is a conceptual diagram showing cargo handling vehicles 100a and 100b when switching plant models.

In the following, the following two cases will be described as examples of switching the plant model.
(B) When the cargo handling vehicle 100a shifts from the forward straight line running without a load (work ID 1-2 in FIG. 4) to the forward right turn running without a load (work ID 3-2 in FIG. 4). ..
(B) When the cargo handling vehicle 100b shifts from a right spin turn with a load (work ID 8-1 in FIG. 4) to a reverse straight line running with a load (work ID 2-1 in FIG. 4).

In FIG. 6, the cargo handling vehicle 100a is in the situation of (a) described above, and is moving forward without a load at the target node 302 from the forward straight line running without a load at the current node 301 (work ID 1-2 in FIG. 4). It is assumed that the work shifts to the right turn running (work ID 3-2 in FIG. 4). For example, when the cargo handling vehicle 100a is located in a circle having a radius L centered on the target node 302, the work determination unit 230 has a distance Lv of the distance L or less (Lv ≦ L), and the cargo handling vehicle 100a is the target. Since the node 302 has been reached, it is determined that the plant model for controlling the cargo handling vehicle 100a is switched.

In FIG. 6, the cargo handling vehicle 100b is in the situation of (b) described above, and when it travels straight (forward travel) and reaches the current node 601 from the traveling node 600 (that is, from the self-position 311 of the cargo handling vehicle 100b to the present). When the distance Lv to the node 601 becomes less than or equal to the distance L), the pallet 304 is currently loaded as a load on the node 601 and the right spin turn with the load (work ID 8-1 in FIG. 4) is executed on the current node 601. do. Then, when the right spin turn with the load is completed, the cargo handling vehicle 100b is assumed to execute the reverse straight line running with the load (work ID 2-1 in FIG. 4). The target link 603 of the cargo handling vehicle 100b is a link connecting the current node 601 and the target node 602.

In the process 505 of FIG. 5, the work determination unit 230 checks whether or not the self-posture 312 has reached the target posture at the current node 601 when the cargo handling vehicle 100b executes a spin turn at the current node 601. It may be determined that the plant model for controlling the cargo handling vehicle 100b is switched when the self-posture 312 of the 100b is currently the target posture at the node 601. In this case, the work determination unit 230 determines that the plant model for executing the spin turn is switched to the plant model for traveling straight. For example, when the plant model is switched, the cargo handling vehicle 100b executes the work of traveling in a reverse straight line with a load (work ID 2-1 in FIG. 4) at the current node 601.

For example, when the cargo handling vehicle 100b executes a right spin turn, the work determination unit 230 has a self-posture 312 with respect to the target link 603 (the angle _φv of the cargo handling vehicle 100b in the front-rear direction YV with respect to the target link 603) at an angle φ or less. If so, it is determined that the self-attitude 312 is currently the target attitude at the node 601 and that the plant model for controlling the cargo handling vehicle 100b is switched. The angle φ is a threshold value indicating whether or not the difference between the self-posture 312 of the cargo handling vehicle 100b and the target posture is large, and can be arbitrarily determined in advance.

If the self-posture 312 (angle φv) is less than or equal to the angle φ, the work determination unit 230 switches the plant model and causes the cargo handling vehicle 100b to execute the reverse straight line running with the load at the current node 601. In this way, the work determination unit 230 switches the plant model that executes the spin turn to the plant model that runs in the reverse straight line according to the self-posture 312 of the cargo handling vehicle 100b, and performs the work of the cargo handling vehicle 100b from the spin turn. It is possible to shift to reverse straight running.

In the process 505 of FIG. 5A, the work determination unit 230 reaches the target node 302 (Lv ≦ L) when the work ID in the target node 302 is different from the work ID in the current node 301 (process 503). In this case, it is determined that the plant model for controlling the cargo handling vehicle 100 is to be switched, and the plant model switching unit 231 is requested to switch the plant model. The work determination unit 230 transmits to the plant model switching unit 231 a request to switch the plant model for controlling the cargo handling vehicle 100 to the plant model corresponding to the work specified by the work ID in the target node 302.

Further, the work determination unit 230 examines whether or not the work ID in the target node 302 is a work ID preset in the route map management unit 205, and the work ID in the target node 302 is the work ID in the current node 301. If the work ID is different from the ID and is preset in the route map management unit 205, the plant model switching unit 231 may be requested to switch the plant model.

FIG. 5B is a flowchart showing another processing flow of the work determination unit 230 and the plant model switching unit 231. In the flowchart shown in FIG. 5B, in the flowchart shown in FIG. 5A, the process 505a is executed instead of the process 505. Only the process 505a will be described with respect to the flowchart shown in FIG. 5B.

In the process 505a, the work determination unit 230 examines whether or not the work ID in the target node 302 is a work ID preset in the route map management unit 205, and the work ID in the target node 302 is the route map management. When the work ID is preset in the unit 205, the plant model switching unit 231 is requested to switch the plant model.

If the work ID in the target node 302 is different from the work ID in the current node 301 but is not a work ID preset in the route map management unit 205, the work specified by this work ID in the target node 302 is cargo handling. It is not the work performed by the vehicle 100. It can be inferred that this work ID at the target node 302 is an erroneously obtained work ID. Therefore, in this case, the cargo handling vehicle 100 stops the work. In this case, the control command generation unit 220 controls to stop the cargo handling vehicle 100, for example, by outputting a command to stop the cargo handling vehicle 100 to the traveling motor drive unit 222. By doing so, the cargo handling vehicle system 200 according to the present embodiment can confirm that the work specified by the work ID at the target node 302 is definitely the work to be performed by the cargo handling vehicle 100.

In the process 506 of FIG. 5A, the plant model switching unit 231 switches the plant model to the plant model corresponding to the work specified by the work ID in the target node 302 in response to the request from the work determination unit 230. When the plant model switching unit 231 inputs a request for switching the plant model from the work determination unit 230, the plant model switching unit 231 transfers the plant model corresponding to the work specified by the work ID in the target node 302 to the plant model management unit 232 of the traffic control unit 201. And output the acquired plant model to the control command generation unit 220. In this way, the plant model switching unit 231 switches the plant model for controlling the cargo handling vehicle 100.

The plant model switching unit 231 is provided in the vehicle-mounted controller 107 in this embodiment, but may be provided in the traffic control unit 201. When the traffic control unit 201 includes the plant model switching unit 231, the in-vehicle controller 107 connects the plant model to the plant model switching unit 231 of the traffic control unit 201 via the communication device 202 and the communication device 203 of the traffic control unit 201. Request a switch.

The plant model in this embodiment will be described together with the explanation of the plant model management unit 232.

Next, the plant model management unit 232 of the traffic control unit 201 will be described.

(Details of Plant Model Management Department 232)
The plant model management unit 232 stores the plant model for each work ID. The plant model is a model showing operating characteristics when a cargo handling vehicle 100 that performs autonomous control performs work. That is, the plant model corresponding to the work specified by the work ID shows the operating characteristics of the cargo handling vehicle 100 when the work specified by the work ID is executed. The plant model is represented by, for example, a transfer function showing the relationship between the command value of the steering motor and the response value thereof, or the equation of motion of the cargo handling vehicle 100. The plant model management unit 232 manages a model (mathematical formula) of a transfer function and an equation of motion and parameters (coefficient values, etc.) for each work ID.

The plant model management unit 232 is provided by the traffic control unit 201 in this embodiment, but may be provided by the vehicle-mounted controller 107.

(Plant model represented by transfer function)
In the following, as an example of the plant model, the transfer function of the traveling motor and the steering motor of the cargo handling vehicle 100 will be described.

FIG. 7A is a diagram showing _a transfer function G1 (s) of the traveling motor. FIG. 7B is a diagram showing an example of the relationship between the command value 701 and the response value 702 of the traveling motor. The transfer function G ₁ (s) of the traveling motor indicates the relationship between the command value 701 (vr) and the response value 702 (vy) of the traveling motor.

_The plant model management unit 232 constructs the transfer function G1 (s) shown in FIG. 7A from the relationship between the command value 701 and the response value 702 of the traveling motor as shown in FIG. 7B by using the traveling data acquired in advance. do. For example, it is assumed that the relationship of the response value 702 (vy) with respect to the command value 701 (vr) of the traveling motor can be expressed by using the transfer function G ₁ (s) shown in the equation (1-1).

In the equation (1-1), s is a variable of the Laplace transform, and a, b, and c are arbitrary constants.

FIG. 8A is a diagram showing a transfer function of the steering motor. FIG. 8B is a diagram showing an example of the relationship between the command value 801 and the response value 802 of the steering motor. FIG. 8B also shows the relationship between the command value 701 and the response value 702 of the traveling motor shown in FIG. 7B. The transfer function of the steering motor indicates the relationship between the command value 801 (θr) and the response value 802 (θy) of the steering motor.

The plant model management unit 232 constructs the transfer function shown in FIG. 8A from the relationship between the command value 801 and the response value 802 of the steering motor as shown in FIG. 8B by using the driving data acquired in advance.

When both the steering motor and the traveling motor are composed of a hydraulic mechanism (for example, a hydraulic motor), the hydraulic oil used to drive the traveling motor is distributed to the steering motor when the steering motor is driven during the turning operation. Sometimes. Therefore, in this embodiment, it is assumed that the response value 802 (θy) of the steering motor is affected by the command value 801 (θr) of the steering motor and the response value 702 (vy) of the traveling motor, and the plant model management unit 232 2. Create a transfer function with 2 inputs and 1 output. In this embodiment, the transfer function G ₂ (s) representing the relationship between the command value 801 (θr) of the steering motor and the response value 802 (θy) of the steering motor is represented by the first-order transfer function of the equation (1-2). It is assumed that the transfer function G ₃ (s) representing the relationship between the response value 702 (vy) of the traveling motor and the correction command value θu of the steering motor can be expressed by the first-order transfer function of Eq. (1-3). do.

In equations (1-2) and (1-3), K1 and K2 are gains (steady value / command value), and t1 and t2 are time constants (response value is 63.2% of steady value (= 1). -1 / e) is the difference between the time when the command is reached and the time when the command is started).

In the cargo handling vehicle system 200 according to the present embodiment, for example, by using transfer functions (plant models) different from each other when the cargo handling vehicle 100 travels in a straight line and when the cargo handling vehicle 100 makes a turn, control with high follow-up accuracy to the target route is performed. Can be realized. For example, it is conceivable to use the transfer function properly according to the following conditions.

Condition 1) Transfer function G ₁ (s)
When the turning radius R at the target node 302 is larger than the radius R0, it is regarded as _a straight line running, and the transfer function G1 (s) showing the relationship between the command value 701 (vr) and the response value 702 (vy) of the running motor. ) Only.

Condition 2) Transfer function G ₂ (s) + G ₃ (s)
When the turning radius R at the target node 302 is less than or equal to the radius R0, it is regarded as turning, and the relationship between the steering motor command value 801 (θr) and the response value 802 (θy) is regarded as the steering motor correction command value (). G ₂ (s) + G ₃ (s), which is a transfer function expressed in consideration of θu), is used.

(Plant model represented by the equation of motion)
In the following, the equation of motion of the cargo handling vehicle 100 will be described as an example of the plant model.

When controlling the speed and angular velocity of the drive wheels of the cargo handling vehicle 100, it is necessary to define the equation of motion of the vehicle such as the vehicle dynamics of the cargo handling vehicle 100. The equation of motion of a vehicle is determined using geometric conditions between wheels such as the wheelbase and tread. In the cargo handling vehicle 100, assuming that the traveling in which the cargo handling member 103 is located in front of the traveling direction is forward, the rear wheel drive is performed during forward traveling, and the front wheels are driven in reverse traveling (travel in which the cargo handling member 103 is located behind in the traveling direction). It becomes a drive. Therefore, for example, even in straight-line traveling, it is necessary to prepare different equations of motion for forward traveling and reverse traveling. Hereinafter, an example of the equation of motion (plant model) will be described for the case where the cargo handling vehicle 100 travels forward (rear wheel drive) and the case where the cargo handling vehicle 100 travels backward (front wheel drive).

FIG. 9 is a diagram showing a cargo handling vehicle 100 traveling forward (rear wheel drive). FIG. 10 is a diagram showing a cargo handling vehicle 100 traveling in reverse (front wheel drive). In FIGS. 9 and 10, X and Y indicate the self-position 311 of the cargo handling vehicle 100. That is, X indicates the position of the cargo handling vehicle 100 in the reference coordinate system 310 in the X direction, and Y indicates the position of the cargo handling vehicle 100 in the reference coordinate system 310 in the Y direction. Further, in FIGS. 9 and 10, l is the wheelbase, tr is the tread, θ is the rotation angle of the vehicle body, δ is the rotation angle of the drive wheels, Vd is the forward speed of the drive wheels, and V is the cargo handling vehicle. The forward speeds of 100 are shown respectively. Although not shown, if the radius of the drive wheel is rd and the rotation speed of the drive wheel is ω, the forward speed Vd of the drive wheel can be expressed by Vd = ω × rd.

Generally, in the case of a vehicle with a maximum speed of about 10 km / h such as a cargo handling vehicle 100, a Kinematic Model (a model derived from a geometrical relationship) that does not consider the slip angle of the wheels can be used for sufficiently accurate control. can. Therefore, in this embodiment, a plant model is defined using the Kinematic Model in order to reduce the number of control elements.

In this embodiment, the equation of motion of the cargo handling vehicle 100 is defined assuming that the slip angles and speeds of the four wheels included in the cargo handling vehicle 100 are equal to each other.

In the case of forward traveling (rear wheel drive) shown in FIG. 9, the equations of motion of the cargo handling vehicle 100 are the equations of motion (1-4), (1-5), and equations of the rear wheel drive shown below. It can be expressed by (1-6).

In the case of reverse traveling (front wheel drive) shown in FIG. 10, the equations of motion of the cargo handling vehicle 100 are the equations of motion (1-7), (1-8), and (1) shown below, which are the equations of motion for front wheel drive. It can be expressed by -9).

In the cargo handling vehicle system 200 according to the present embodiment, for example, by using different equations of motion (plant model) for the case where the cargo handling vehicle 100 travels forward and the case where the cargo handling vehicle 100 travels backward, the tracking accuracy with respect to the target route is high. Control can be realized. For example, it is conceivable to use the equation of motion properly according to the following conditions.

Condition 1) Rear-wheel drive equation of motion When the cargo handling vehicle 100b in FIG. 6 reaches the current node 601 from the traveling node 600 (that is, the distance Lv from the self-position 311 of the cargo handling vehicle 100b to the current node 601 is the distance L). In the larger case), the rear-wheel drive equation of motion is used because the cargo handling vehicle 100b travels forward.

Condition 2) Front-wheel drive equation of motion When the cargo handling vehicle 100b performs a right spin turn at the current node 601 in FIG. 6, if the self-attitude 312 (angle φv) with respect to the target link 603 is an angle φ or less, the cargo handling vehicle 100b Ends the right spin turn and runs backwards, so the front-wheel drive equation of motion is used.

In the cargo handling vehicle system 200 according to this example, the cargo handling vehicle 100 automatically acquires the work to be performed and automatically switches the plant model according to the acquired work (work ID), so that the cargo handling vehicle 100 travels at a high speed. It is possible to control with precision. Further, by using the cargo handling vehicle system 200 according to this embodiment, the traveling of the cargo handling vehicle 100 can be controlled with high accuracy. Therefore, when the cargo handling vehicle 100 is traveling, for example, the amount of deviation from the desired route is smaller, and the target position is reached. It is possible to shorten the route when moving to, and it is possible to improve the transport efficiency of the cargo handling vehicle 100. Further, by using the cargo handling vehicle system 200 according to this example, the arrangement of the cargo in the warehouse can be designed according to the plant model, so that the restrictions on the arrangement of the cargo in the warehouse are reduced and the transport efficiency of the cargo handling vehicle 100 is improved. Not only can it be made to, but it can also be optimized for the placement of cargo in the warehouse.

The cargo handling vehicle system 200 according to the second embodiment of the present invention will be described with reference to FIGS. 11 to 12B. The cargo handling vehicle system 200 according to the present embodiment has substantially the same configuration as the cargo handling vehicle system 200 according to the first embodiment, but differs from the cargo handling vehicle system 200 according to the first embodiment in that the traffic control unit 201 includes a learning processing unit. The learning processing unit includes a learning data selection unit 1100, a learning unit 1101, and a database update unit 1102, and updates the plant model corresponding to the work specified by the work ID.

Hereinafter, the learning data selection unit 1100, the learning unit 1101, and the database update unit 1102, which are the learning processing units included in the cargo handling vehicle system 200 according to the present embodiment, will be described.

FIG. 11 is a functional block diagram showing the configuration of the cargo handling vehicle system 200 according to the present embodiment. In the cargo handling vehicle system 200 according to the present embodiment, in the cargo handling vehicle system 200 according to the first embodiment (FIG. 2), the traffic control unit 201 further adds a learning processing unit (learning data selection unit 1100, learning unit 1101 and database update unit 1102). It is configured to be prepared.

(Learning data selection unit 1100)
The learning data selection unit 1100 inputs the work ID of the current node 301 of the cargo handling vehicle 100 from the work determination unit 230 of the vehicle-mounted controller 107. Further, the learning data selection unit 1100 receives command values for controlling the cargo handling vehicle 100 at the current node 301 from the control command generation unit 220 (for example, steering motor drive unit 221, traveling motor drive unit 222, brake drive unit 223, etc.). (Command value to the transfer device / cargo handling member motor drive unit 224) and the response value of the cargo handling vehicle 100 to this command value (response value of each drive unit to the command value) are input. The learning data selection unit 1100 outputs the input work ID, command value, and response value in the current node 301 to the learning unit 1101 as learning data.

(Learning unit 1101)
The learning unit 1101 inputs the work ID in the current node 301, the command value to the cargo handling vehicle 100, and the response value of the cargo handling vehicle 100 to the command value from the learning data selection unit 1100, and uses the command value and the response value for learning. Update the plant model by machine learning used as data.

In the following, as an example, the learning unit 1101 uses a command value for the steering motor of the cargo handling vehicle 100 and a response value from the steering motor, and a plant model (a plant represented by a transmission function) by machine learning using feed forward control. An example of updating the parameters of the model) will be described.

The learning unit 1101 acquires the command value θr and the response value θy of the steering motor when the cargo handling vehicle 100 makes a turn during forward traveling or a turning during reverse traveling from the learning data selection unit 1100. In this embodiment, the learning unit 1101 obtains a different transfer function for turning during forward traveling and turning during reverse traveling as a transfer function indicating the responsiveness of the cargo handling vehicle 100. The learning unit 1101 can reduce the error between the command value and the response value by obtaining the inverse response by using the obtained transfer function, and can improve the accuracy of the path tracking function.

FIG. 12A is a diagram showing a transfer function showing the responsiveness of the steering motor. It is assumed that the relationship of the response value θy with respect to the command value θr of the steering motor is expressed by the transfer function P (s). It is assumed that the transfer function P (s) is expressed by the equation (2-1).

In the equation (2-1), s is a variable of the Laplace transform, and a, b, and c are arbitrary constants (parameters).

In the learning unit 1101, the relationship of the response value θy with respect to the command value θr of the steering motor is expressed by the transfer function P (s) of FIG. 12A, and the transfer function P (s) is expressed by the equation (2-1).

The learning unit 1101 can obtain the inverse response P ^-1 (s) using the transfer function P (s) shown in the equation (2-1), and constitutes the feed forward control F (s) shown in FIG. 12B. It is possible to do.

FIG. 12B is a diagram showing feedforward control using a transfer function indicating the responsiveness of the steering motor obtained by the learning unit 1101.

It is desirable that the response value θy of the steering motor has as high a response as possible to the command value θr. Therefore, consider the feedforward control F (s) as shown in FIG. 12B. The output of the feedforward control F (s) is the correction command value θu of the steering motor. Therefore, the correction command value θu of the steering motor calculated by the control command generation unit 220 is transmitted to the steering motor drive unit 221 (FIG. 11).

The feedforward control F (s) is given by, for example, the equation (2-2).

In equation (2-2), ωc and ηc are arbitrary constants.

Equation (2-2) can be expressed as equation (2-4) using the transfer function L (s) shown in equation (2-3).

As shown in FIG. 12B, the response value θy with respect to the command value θr of the steering motor can be arbitrarily designed by the transfer function L (s) shown in the equation (2-3). Therefore, if the transfer function P (s) indicating the relationship of the response value θy with respect to the command value θr of the steering motor is obtained in advance, the steering motor can be adjusted to give a desired response.

The learning unit 1101 acquires a data set of the command value θr and the response value θy of the steering motor as learning data, and uses the command value θr and the response value θy to identify the system focusing on the least squares method and the frequency response. The transfer function P (s) can be appropriately calculated and the transfer function P (s) can be updated sequentially. The learning unit 1101 obtains and updates the three parameters a, b, and c of the transfer function P (s) shown in the equation (2-1) to obtain and update the plant model (plant model represented by the transfer function). The parameters can be updated.

(Database update unit 1102)
The database update unit 1102 acquires the parameters of the plant model updated by the learning unit 1101 (for example, the parameters a, b, c of the transfer function P (s) shown in the equation (2-1)) from the learning unit 1101. The parameter values of this plant model are updated for each work ID. The database update unit 1102 outputs the updated plant model to the plant model management unit 232.

The plant model management unit 232 stores the plant model updated by the database update unit 1102 for each work ID.

The cargo handling vehicle system 200 according to the present embodiment includes a learning processing unit (learning data selection unit 1100, learning unit 1101, and database update unit 1102) for updating the plant model, and learning data for improving the accuracy of the plant model. Can be appropriately and automatically generated for each work ID. Therefore, the cargo handling vehicle system 200 according to the present embodiment can be provided with a tuningless control system, so that the engineering cost at the time of introducing the system can be reduced.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and the present invention is not necessarily limited to the embodiment including all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to delete a part of the configuration of each embodiment and add / replace another configuration.

100, 100a, 100b ... Cargo handling vehicle, 101 ... Vehicle frame, 102 ... Transfer device, 103 ... Cargo handling member, 104 ... External sensor, 105 ... Acceleration sensor, 106 ... Load sensor, 107 ... In-vehicle controller, 200 ... Cargo handling vehicle system , 201 ... Traffic control unit, 202 ... Vehicle-mounted controller communication device, 203 ... Traffic control unit communication device, 204 ... Operation management unit, 205 ... Route map management unit, 206 ... Travel route generation unit, 214 ... Self-position / attitude calculation 215 ... Nearest node calculation unit 216 ... Load load calculation unit 217 ... Vehicle body behavior calculation unit, 220 ... Control command generation unit 221 ... Steering motor drive unit 222 ... Travel motor drive unit 223 ... Brake drive unit , 224 ... Transfer device / cargo handling member motor drive unit, 230 ... Work determination unit, 231 ... Plant model switching unit, 232 ... Plant model management unit, 301 ... Travel node (current node), 302 ... Travel node (target node) , 303 ... link (target link), 304 ... pallet, 305 ... segment, 306 ... terminal node, 307 ... shelf, 310 ... reference coordinate system, 311 ... self-position, 312 ... self-attitude, 600 ... traveling node, 601 ... present Node, 602 ... Target node, 603 ... Target link, 701 ... Travel motor command value, 702 ... Travel motor response value, 801 ... Steering motor command value, 802 ... Steering motor response value, 1100 ... Learning data selection unit 1101 ... Learning unit 1102 ... Database update unit.

Claims (5)

1. It is equipped with a cargo handling member on which the cargo carried by the cargo handling vehicle is placed, a control command generation unit, a travel route generation unit, a nearest neighbor node calculation unit, a work determination unit, and a plant model switching unit.
   The control command generation unit controls the cargo handling vehicle according to a plant model showing the operating characteristics when the cargo handling vehicle performs work.
   The travel route generation unit creates a travel route for the cargo handling vehicle, and the travel route is composed of a plurality of nodes indicating positions through which the cargo handling vehicle passes and one or more links connecting the two nodes. Each of the nodes is provided with a work ID indicating the work to be performed by the cargo handling vehicle.
   The nearest node calculation unit inputs the position of the cargo handling vehicle and the travel route, and among the nodes constituting the travel route, finds the node closest to the position of the cargo handling vehicle as the current node. Among the nodes constituting the travel route, the target node, which is the node to be passed by the cargo handling vehicle next to the current node, is obtained.
   The work determination unit compares the work ID at the current node with the work ID at the target node.
   When the work ID at the current node and the work ID at the target node are different from each other, the plant model switching unit responds to the work specified by the work ID at the target node with the plant model. Switch to the plant model
   A cargo handling vehicle system characterized by that.
2. The work determination unit determines whether or not the distance from the position of the cargo handling vehicle to the target node is equal to or less than a predetermined distance.
   In the plant model switching unit, the work ID at the current node and the work ID at the target node are different from each other, and the distance from the position of the cargo handling vehicle to the target node is equal to or less than the predetermined distance. In that case, the plant model is switched to the plant model corresponding to the work specified by the work ID at the target node.
   The cargo handling vehicle system according to claim 1.
3. It is equipped with a route map management unit that stores two-dimensional map data of the range in which the cargo handling vehicle travels and has a preset work ID.
   The plant model switching unit is
   When the work ID at the current node and the work ID at the target node are different from each other, and the work ID at the target node is the work ID set in the route map management unit, the work ID is the same. The plant model is switched to the plant model corresponding to the work specified by the work ID at the target node.
   The cargo handling vehicle system according to claim 1 or 2.
4. In the control command generation unit, the work ID at the current node and the work ID at the target node are different from each other, and the work ID at the target node is set in the route map management unit. If not, the control for stopping the cargo handling vehicle is carried out.
   The cargo handling vehicle system according to claim 3.
5. It is equipped with a learning processing unit that updates the plant model.
   The learning processing unit inputs a command value for controlling the cargo handling vehicle and a response value of the cargo handling vehicle to the command value from the control command generation unit, and the machine using the command value and the response value. Update the parameters of the plant model by learning,
   The cargo handling vehicle system according to claim 1.

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