JP6772912B2 - Wagon transport system - Google Patents

Description

The present invention relates to a wagon transport system.

Robots include robots that move on a fixed orbit and robots that perform autonomous movement. As one of the transfer systems in factories and the like, there is a transfer system by a robot. Patent Document 1 discloses a transport system in which a transport robot holds a wagon on which an object is placed and transports the wagon by moving on a predetermined target trajectory.

JP-A-2009-006415

However, with the conventional transfer robot, it is difficult to perform autonomous movement while holding the wagon. The reason is that when the transfer robot holds the wagon, the wagon is located in the transfer direction of the transfer robot, so that the transfer robot recognizes that the wagon is an obstacle.

The present invention has been made in view of the above problems, and provides a wagon transport system capable of autonomously avoiding obstacles while holding a wagon.

The wagon transport system according to the present invention is a wagon transport system that transports a wagon by an autonomous mobile robot, and the autonomous mobile robot holds a recognition sensor that recognizes the wagon and the wagon that is recognized by the recognition sensor. The wagon is provided with a holding portion and an optical sensor for detecting an obstacle located in front of the transport direction of the wagon, and the wagon has a feature portion for being recognized by the recognition sensor and the optical sensor. The columns of the wagon located on the optical path of the sensor light of the above are made of a light-transmitting material that transmits the sensor light by a predetermined amount or more, and the autonomous mobile robot uses the wagon recognized by the recognition sensor. While being held and conveyed by the holding portion, obstacles detected by the optical sensor are autonomously avoided.

In the wagon transport system according to the present invention, the support of the wagon located on the optical path of the sensor light of the optical sensor is composed of a light-transmitting material that transmits the sensor light by a predetermined amount or more, and the autonomous mobile robot recognizes it. While the wagon recognized by the sensor is held by the holding unit and conveyed, obstacles detected by the optical sensor are autonomously avoided. With such a configuration, the autonomous mobile robot can autonomously avoid obstacles while holding the wagon.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a wagon transfer system in which an autonomous mobile robot can autonomously avoid obstacles while holding a wagon.

It is a side view of the wagon transport system which concerns on Embodiment 1. FIG. FIG. 5 is a plan view showing a positional relationship between a laser sensor provided on a leg of a robot according to the first embodiment and a transparent support column provided on a pedestal of a wagon. It is a flowchart which shows the transfer process of the wagon transfer system which concerns on Embodiment 1. FIG. It is a side view of the wagon transport system which concerns on Embodiment 2. FIG.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, the drawings have been simplified as appropriate to clarify the description.
As a matter of course, the right-handed xyz coordinates shown in FIGS. 1, 2 and 4 are for convenience to explain the positional relationship of the components. Usually, the z-axis plus direction is vertically upward, and the xy plane is a horizontal plane, which is common between drawings.

<Embodiment 1>
FIG. 1 is a side view of the wagon transport system according to the first embodiment. In the present embodiment, the robot 10 holds the wagon 20 and starts autonomous movement for carrying while avoiding obstacles. The robot 10 includes a leg portion 11, a body portion 12, and a head portion 13. The wagon 20 includes a pedestal portion 21, wheels 22, a transparent strut 23a, a strut 23b, a basket portion 24a and a basket portion 24b, and a handle 25.

<Structure of robot 10>
First, the configuration of the robot 10 will be described.
The robot 10 includes a leg portion 11, a body portion 12, and a head portion 13. The leg portion 11 includes a laser sensor 14 on the upper surface (the surface on the positive side of the z-axis).

As shown in FIG. 1, the laser sensor 14 is provided on the upper surface (the surface on the positive side of the z-axis) of the leg portion 11 of the robot 10. The laser sensor 14 irradiates the laser beam L (broken line) toward the front of the wagon 20 in the transport direction (positive direction of the x-axis) to detect an obstacle located in front of the transport direction of the wagon 20 (positive direction of the x-axis). It is an optical sensor that detects.

On the optical path of the laser beam L emitted from the laser sensor 14, a transparent column 23a, which is a column of a wagon and is made of a light-transmitting material, is provided. The reason why the transparent support 23a made of a light-transmitting material is used as the support of the wagon is to prevent the laser sensor 14 of the robot 10 from erroneously recognizing that the transparent support 23a of the wagon 20 is an obstacle. Because. Details will be described later.

As shown in FIG. 1, the body portion 12 includes an arm 15 connected to the body portion 12 and a hand 16 provided on the arm 15. The hand 16 is a holding portion that holds the handle 25 of the wagon 20. In the present embodiment, the hand 16 is used to hold the handle 25 of the wagon 20, but any shape can be used as long as it is a holding portion capable of holding the handle 25. Good. Further, the handle 25 of the wagon 20 is not limited to the one that grips the handle 25, and may be held by using a magnetic force or the like.

As shown in FIG. 1, the head 13 includes a camera 17. The camera 17 is provided on the head 13 of the robot 10. The camera 17 is an AR (Augmented Reality) marker provided on the handle 25 of the wagon 20, or an optical recognition sensor that detects a characteristic pattern, shape, or the like. Examples of the characteristic pattern provided on the handle 25 of the wagon 20 include a black-and-white pattern, a striped pattern, and an uneven texture, but any pattern or shape that easily appears as an image feature amount may be used.

In the present embodiment, the detection area of the camera 17 is indicated by a long-dotted line, which is an example. Since the head 13 is movable, the camera 17 provided on the head 13 can be moved in any direction up, down, left, and right. Therefore, the detection area of the camera 17 changes each time as the head 13 moves.

Further, in the present embodiment, the camera 17 which is an optical recognition sensor is used, but the sensor is not limited to this as long as it can recognize the handle 25 of the wagon 20. As a substitute for the camera 17 and the AR marker, for example, an RFID (Radio Frequency Identifier) or the like capable of non-contact reading using radio waves may be used.

<Structure of wagon 20>
Next, the configuration of the wagon 20 will be described.
As shown in FIG. 1, the wagon 20 includes a pedestal portion 21, wheels 22 and transparent columns 23a provided on the pedestal portion 21, a basket portion 24a supported by the transparent columns 23a, columns 23b, and columns. It includes a basket portion 24b supported by the 23b and a handle 25 provided on the basket portion 24b.

As shown in FIGS. 1 and 2, the pedestal portion 21 is, for example, a rectangular plate-shaped member in a plan view provided at the bottom of the wagon 20. As shown in FIG. 1, the wheels 22 are fixed to the four corners of the lower surface (the surface on the negative side of the z-axis) of the pedestal portion 21. The number of wheels of the wheel 22 is, for example, four wheels, but it may be three wheels or six wheels, and the number of wheels does not matter as long as it can carry luggage on the wagon 20. .. Further, it is preferable that the wheel 22 is provided so as to be rotatable around the z-axis.

As shown in FIGS. 1 and 2, the transparent column 23a is a columnar member fixed to the four corners of the upper surface (the surface on the positive side of the z-axis) of the pedestal portion 21 and is vertically upward (positively oriented on the z-axis). It has been extended. The transparent column 23a is made of a light-transmitting material.

The light-transmitting material in the present embodiment refers to a material that transmits a predetermined amount or more of the laser light L emitted from the laser sensor 14 provided on the leg 11 of the robot 10. Examples of the light-transmitting material constituting the transparent support column 23a include glass, acrylic, and polycarbonate, but the light-transmitting material is not limited to this as long as it is a light-transmitting material that transmits laser light L in a predetermined amount or more. The shape of the transparent column 23a is preferably cylindrical from the viewpoint of reducing the reflected light R from the transparent column 23a, but the laser beam L can be transmitted by a predetermined amount or more and the strength of the wagon 20 can be maintained. The shape is not particularly limited as long as it is a thing.

Further, the transparent support column 23a can be adjusted to an arbitrary height. Therefore, it is possible to change the position (z-axis direction) of the transparent support column 23a according to the optical path of the laser beam L emitted from the laser sensor 14. When the transparent column 23a is provided on the wagon 20, a combination having a high transmittance of the laser light L in the transparent column 23a is selected in consideration of the relationship between the wavelength of the laser beam L and the thickness of the material used for the transparent column 23a. To do.

As shown in FIG. 1, the basket portion 24a and the basket portion 24b have, for example, a box-shaped shape in which the upper surface (the surface on the positive side of the z-axis) is open, and are suitable for transporting a target load. The shape can be changed as appropriate. The basket portion 24a is provided on the upper side (the surface on the positive side of the z-axis) of the transparent support column 23a. That is, the basket portion 24a is supported by the transparent support column 23a. Further, the columns 23b are provided at the four corners of the bottom surface of the basket portion 24a. The basket portion 24b is provided on the upper side (the surface on the positive side of the z-axis) of the support column 23b. That is, the basket portion 24b is supported by the support column 23b.

The support column 23b is a support column made of a material having a lower transparency of the laser beam L than the transparent support column 23a. The support column 23b may be made of a material that can maintain the strength of the wagon 20. For example, it may be composed of the same light-transmitting material as the transparent column 23a, or may be composed of an opaque substance such as metal.

In the present embodiment, the transparent columns 23a are provided at the four corners of the upper surface (the surface on the positive side of the z-axis) of the pedestal portion 21, but the transparent columns 23a transmit the laser beam L and carry the load on the wagon 20. The number of transparent columns 23a does not matter as long as it can be configured. Similarly, the columns 23b are provided at the four corners of the bottom surface of the basket portion 24a, but the number of columns 23b does not matter as long as the wagon 20 can carry the load.

As described above, the handle 25 is provided with an AR (Augmented Reality) marker, or a characteristic pattern or shape. Examples of the characteristic pattern provided on the handle 25 include a black-and-white pattern, a striped pattern, and an uneven texture. The pattern or shape may be easily detected by the camera 17 of the robot 10 as an image feature amount. Anything is fine.

FIG. 2 is a plan view showing the positional relationship between the laser sensor provided on the leg portion of the robot according to the first embodiment and the transparent support column provided on the pedestal portion of the wagon. 1 and 2 correspond to each other. Similar to FIG. 1, the robot 10 holds the wagon 20 and starts autonomous movement for carrying while avoiding obstacles. Here, the state in which the robot 10 holds the wagon 20 means that the wagon 20 is located in the transport direction (x-axis positive direction) for the robot 10. Since the laser beam L emitted from the laser sensor 14 of the robot 10 detects an obstacle located in the transport direction (positive direction on the x-axis), the robot 10 mistakenly determines that the wagon 20 is an obstacle to the robot 10. It is necessary to prevent it from being recognized.

Therefore, in the present embodiment, the columns of the wagon 20 provided on the optical path of the laser beam L emitted from the laser sensor 14 are composed of the transparent columns 23a as described above. Since the transparent support column 23a is made of glass, which is a light-transmitting material, the laser beam L can be transmitted by a predetermined amount or more. The fact that the transparent support column 23a constituting the wagon 20 transmits the laser beam L means that the laser sensor 14 does not detect the wagon 20 as an obstacle.

By making the support of the wagon 20 a transparent support 23a in this way, it is possible to prevent the robot 10 from erroneously recognizing that the wagon 20 is an obstacle to the robot 10. Therefore, the robot 10 can detect obstacles by the laser beam L emitted from the laser sensor 14 while transporting the wagon 20, and can perform autonomous movement to avoid the detected obstacles.

However, as shown in FIG. 2, reflected light R may occur. The reflected light R refers to a case where the laser light L is reflected without partially passing through the transparent support column 23a depending on the conditions of the laser sensor 14 and the material of the transparent support column 23a. When the reflected light R is generated, the robot 10 erroneously recognizes the wagon 20 as an obstacle based on the reflected light R, and it is necessary to prevent such erroneous recognition. Therefore, when the reflected light R is generated, a process of removing the reflected light R is performed.

The robot 10 holds information on the relative positional relationship between the laser sensor 14 of the robot 10 and the transparent support column 23a of the wagon 20 in a state where the robot 10 holds the wagon 20 in advance. Based on the information on the relative positional relationship between the laser sensor 14 and the transparent column 23a, it is detected whether or not the reflected light R is generated by the transparent column 23a. Here, since the reflected light R generated by the reflection region RA (thick solid line portion of the transparent support column 23a) in FIG. 2 is detected as the reflected light R generated by the transparent support column 23a, the reflected light R is the control unit. Is removed by. By performing such a removal process of the reflected light R, it is possible to prevent the robot 10 from erroneously detecting the wagon 20 as an obstacle.

As described above, the reflected light R is not always generated in the reflection region RA of the transparent support column 23a, and whether the laser light L is transmitted or reflected depends on the conditions of the laser sensor 14 and the material of the transparent column 23a. Further, in the present embodiment, the robot 10 holds in advance the information on the relative positional relationship between the laser sensor 14 of the robot 10 and the transparent support column 23a of the wagon 20, but the relative position between the laser sensor 14 and the transparent support column 23a. As the positional relationship, the result of recognizing a marker or the like by the camera 17 can also be used.

<Transport process of wagon transfer system>
Hereinafter, a series of flows of the wagon transport system according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 3 is a flowchart showing a transfer process of the wagon transfer system according to the first embodiment. Hereinafter, the details of each step will be described with reference to FIGS. 1 and 2. Note that FIGS. 1 and 2 show step S4, and steps S1 to S3 and S5 are not shown. Therefore, steps S1 to S3 and S5 will be described with reference to FIGS. 1 and 2. Further, all of the series of controls are performed by the control unit (not shown).

<Step S1>
First, the robot 10 moves on the floor F and heads for the storage place of the wagon 20. The location of the wagon 20 is known to the robot 10. Here, "known" means, for example, having the robot 10 hold xy coordinate information in a map in the environment in which the robot 10 operates. When the robot 10 autonomously moves to the place where the wagon 20 is placed, both the laser sensor 14 provided on the leg 11 of the robot 10 and the camera 17 provided on the head 13 are in operation. While the robot 10 autonomously moves to the storage place of the wagon 20, the robot 10 irradiates the laser beam L from the laser sensor 14 provided on the leg 11 of the robot 10 to detect an obstacle in the traveling direction (x-axis positive direction). Detect and avoid.

<Step S2>
The robot 10 that has moved to the storage place of the wagon 20 recognizes the wagon 20. Specifically, the robot 10 recognizes the wagon 20 by detecting the AR marker provided on the handle 25 of the wagon 20 by the camera 17 of the robot 10.

<Step S3>
The robot 10 that recognizes the wagon 20 holds the handle 25 of the wagon 20 by the hand 16. When the robot 10 recognizes the wagon 20, the distance by which the robot 10 moves the arm 15 and the hand 16 to the handle 25 of the wagon 20 in order to hold the handle 25 of the wagon 20 is known. Here, what is known means that the robot 10 holds in advance the relative position information between the hand 16 of the robot 10 and the handle 25 of the wagon 20.

<Step S4>
As shown in FIGS. 1 and 2, the robot 10 holding the wagon 20 detects an obstacle by the laser beam L emitted from the laser sensor 14 while transporting the wagon 20 and avoids the detected obstacle. Start autonomous movement.

<Step 5>
As for the destination, the user can set an arbitrary destination using a tablet or the like. The robot 10 holding the wagon 20 recognizes the coordinates of the destination given to the user (xy coordinates of the map in the environment in which the robot operates) as the transport destination, and transports the robot 10 by autonomous movement avoiding obstacles.
The above is a series of flow of the wagon transport system according to the first embodiment.

With a conventional transfer robot, it has been difficult to perform autonomous movement while holding the wagon. The reason is that when the transfer robot holds the wagon, the wagon is located in the traveling direction of the transfer robot, so that the transfer robot recognizes that the wagon is an obstacle.

Therefore, in the wagon transport system 1 of the present embodiment, the support columns 23a of the wagon 20 located on the optical path of the laser beam L of the optical sensor 14 are made of a light transmitting material that transmits the laser beam L by a predetermined amount or more. There is. Then, the autonomous mobile robot 10 autonomously avoids the obstacle detected by the optical sensor 14 while holding and transporting the wagon 20 recognized by the recognition sensor 17 by the holding unit 16. With such a configuration, the autonomous mobile robot 10 can autonomously avoid obstacles while holding the wagon 20.

<Embodiment 2>
FIG. 4 is a side view of the wagon transport system according to the second embodiment. In the present embodiment, the robot 30 holds the wagon 40 and starts autonomous movement for carrying while avoiding obstacles. The robot 30 includes legs 11, a body 12, and a head 13. In the first embodiment, the laser sensor 14 of the robot 10 is provided on the leg portion 11 (z-axis direction), whereas in the second embodiment, the laser sensor 34 of the robot 30 is provided on the body portion 12. Has been done.

Specifically, the laser sensor 34 is provided so as to be adjacent to the arm 15 of the body portion 12 of the robot 30. The laser beam L emitted from the laser sensor 34 passes between the basket portions 24a and 24b. In the present embodiment, the transparent support column 43a is provided between the basket portion 24a and the basket portion 24b, and the support column 43b is provided between the pedestal portion 21 and the basket portion 24a. Similar to the first embodiment, the transparent support column 43a is made of a light-transmitting material, and the support column 43b is a support column made of a material having a lower transparency of laser light L than the transparent support column 43a. Other than this, it is the same as that of the first embodiment.

The present invention is not limited to the above embodiment, and can be appropriately modified without departing from the spirit.

1, 2 Wagon transfer system 10, 30 Robot 11 Leg 12 Body 13 Head 14, 34 Laser sensor 15 Arm 16 Hand 17 Camera 20, 40 Wagon 21 Pedestal 22 Wheels 23a, 43a Transparent columns 23b, 43b Supports 24a, 24b Basket 25 Handle F Floor L Laser light R Reflected light RA Reflected area

Claims (1)

A wagon transport system that transports wagons using autonomous mobile robots.
The autonomous mobile robot
A recognition sensor that recognizes the wagon and
A holding unit that holds the wagon recognized by the recognition sensor,
An optical sensor for detecting an obstacle located in front of the wagon in the transport direction is provided.
The wagon has a feature portion for being recognized by the recognition sensor, and also
The columns of the wagon located on the optical path of the sensor light of the optical sensor are made of a light-transmitting material that transmits the sensor light in a predetermined amount or more.
The autonomous mobile robot autonomously avoids obstacles detected by the optical sensor while holding and transporting the wagon recognized by the recognition sensor by the holding unit.
Wagon transport system.

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