HK1245218B - Robot for transporting storage bins - Google Patents

Description

Robots used to transport storage bins

Technical Field

The present invention relates to a remotely operated vehicle or robot for picking up a storage bin from a storage system, and a storage system for the storage bin.

Background Art

Remotely operated vehicles for picking up storage bins from storage systems are known. A detailed description of a related prior art storage system is presented in WO 98/49075, and details of a prior art vehicle suitable for this storage system are disclosed in detail in Norwegian Patent No. 317366. This prior art storage system comprises a three-dimensional storage grid comprising storage bins stacked on top of each other up to a certain height. The storage grid is typically constructed as aluminum columns interconnected by top rails, onto which a plurality of remotely operated vehicles, or robots, are arranged to move laterally. Each vehicle is equipped with a lifting mechanism for picking up, carrying, and placing bins stored in the storage grid, and a rechargeable battery for supplying power to the vehicle incorporating a motor. The vehicle typically communicates with a control system via a wireless link and is recharged at a charging station when needed (typically, at night).

An example of a prior art storage system is illustrated in FIG1 . The storage system 3 includes a plurality of carriers or robots 1 configured to move in the X-axis and Y-axis directions (see Cartesian coordinate system 100 ) on dedicated support rails 13 and to receive storage boxes 2 from storage columns within a storage grid 15 of a storage bin. The prior art storage system 3 may also include a dedicated bin lift 50 arranged to receive storage boxes 2 from the carriers 1 at the top level of the storage system 3 and to transport the storage boxes 2 vertically downward to a delivery station, or port 60.

However, with this known system, each carrier is covering a cross-section of the underlying storage system corresponding to two storage pens, thereby limiting the maximum number of simultaneously operating carriers.

It is therefore an object of the present invention to provide a carrier and storage system that allows a significant increase in the number of carriers that can be operated simultaneously during the successful loading and unloading of a storage bin.

Summary of the Invention

Specifically, the present invention relates to a remotely operated vehicle adapted to pick up a storage bin from an underlying storage system, the remotely operated vehicle comprising: a vehicle lift adapted to lift the storage bin from the underlying storage system; a first vehicle rolling mechanism comprising a first rolling assembly and a second rolling assembly disposed on oppositely facing side walls of the vehicle body, allowing movement of the vehicle in a first direction (X) on the underlying storage system during use; and a second vehicle rolling mechanism comprising a first rolling assembly and a second rolling assembly disposed on oppositely facing side walls of the vehicle body, allowing movement of the vehicle in a second direction (Y) on the underlying storage system during use, the second direction (Y) being perpendicular to the first direction (X), wherein each of the rolling assemblies comprises at least two rollers. The first and second rolling assemblies may also comprise belts, chain tracks, or any other mechanism or combination of mechanisms that effect forward and/or backward movement of the vehicle on the underlying storage system.

The vehicle further comprises: a first drive means located within or at least partially within the first vehicle rolling means and adapted to provide a rolling assembly specific drive force to the vehicle in a first direction (X); a second drive means located within or at least partially within the second vehicle rolling means and adapted to provide a rolling assembly specific drive force to the vehicle in a second direction (Y); and motor control electronics disposed within a volume between two of the rollers of each rolling assembly, wherein the motor control electronics are configured to supply power to the first vehicle rolling means and the second vehicle rolling means. During use, at least one of the first vehicle rolling means and the second vehicle rolling means is in contact with an underlying storage system.

In an advantageous embodiment, at least one of the drive means comprises an electric motor using permanent magnets, such as a brushless electric direct current (DC) motor.

In another advantageous embodiment, at least one of the first drive means and the second drive means comprises a rotor magnet, which is arranged at the inner surface of the outer periphery of the respective carrier rolling means of the first drive means and the second drive means.

In another advantageous embodiment, at least one of the first drive means and the second drive means comprises a stator, which is arranged at least partially, preferably completely, in the same rotational plane as the carrier rolling means and at least partially, preferably completely, in the carrier body. In this embodiment, the rotational plane means a plane extending perpendicularly from the rotational axis of the carrier rolling means.

In another advantageous embodiment, the carrier includes means for measuring (at least indirectly) the electromotive force (EMF) of at least one of the carrier's rolling means, in signal communication with one of the stator and rotor, thereby allowing for specific speed alignment of the carrier's rolling assembly during operation. For example, a back-EMF measurement circuit may be installed in signal communication with the carrier's rolling means. Hall sensors may be used alternatively or in combination.

In another advantageous embodiment, the carrier includes a rotary encoder connected (at least indirectly) to at least one of the first carrier rolling means and the second carrier rolling means, thereby allowing angular position feedback during operation. This rotary encoder is suitable for converting the angular motion of the carrier rolling means into an analog or digital code. The rotary encoder (or shaft encoder) can be of the absolute rotary encoder type and/or the absolute multi-turn encoder type. The absolute rotary encoder can be at least one of a mechanical encoder, an optical encoder, a magnetic encoder, and a capacitive encoder. Furthermore, the absolute multi-turn encoder can be at least one of a battery-powered multi-turn encoder, a geared multi-turn encoder, and a self-powered multi-turn encoder.

In another advantageous embodiment, the rotary encoder is a rotary encoder disk which is arranged within the outer periphery of at least one of the first carrier rolling means and the second carrier rolling means, preferably between the outer periphery and the rotor magnets.

In another advantageous embodiment, the carrier further comprises means for measuring the acceleration of at least one of the first carrier rolling means and the second carrier rolling means, the means being in signal communication with the stator. The means preferably comprises one or more piezoelectric sensors, such as accelerometers from PCB ^™ Piezotronics. One or more inductive sensors may be used as an alternative to, or in combination with, the piezoelectric sensors.

In another advantageous embodiment, each rolling assembly comprises at least two rollers, and the carrier further comprises motor control electronics disposed within the volume between two of the rollers of each rolling assembly. In this embodiment, the motor control electronics are configured to supply power to the first and second carrier rolling means and preferably also to transmit communication signals.

In another advantageous embodiment, the first carrier rolling means comprises four X-axis rollers rotating in a first direction with the direction of rotation of the first carrier rolling means, and the second carrier rolling means comprises four Y-axis rollers rotating in a second direction with the direction of rotation of the second carrier rolling means, wherein each of the X-axis rollers and each of the Y-axis rollers are drivingly connected to the first drive means and the second drive means, respectively. Each of the rollers preferably comprises: a plurality of rotor magnets (e.g., in the form of rotor magnet disks) arranged within the inner surface of the roller's outer periphery; and a plurality of stators (e.g., in the form of stator disks) arranged at least partially (e.g., completely) within the carrier body, preferably at the same or approximately the same height relative to the position of the roller's axis of rotation. The height in this document represents the distance from the highest point of the underlying storage system during use. The stators include both windings and yokes, and the stator field windings follow the outer periphery of the roller.

In a further advantageous embodiment, at least a part of the drive means, and preferably all of it, is arranged within the outer circumference of the roller.

For example, when four belts are used to drive the carrier of the present invention in the X-axis and Y-axis directions, a total of four motors can be installed in operative engagement with each of the four belts to achieve the desired specific driving force of the rolling assembly. Similarly, when four belts are used to drive the carrier in the X-axis and Y-axis directions, a total of eight motors can be installed in operative engagement with each of the eight rollers to achieve the desired specific driving force of the rolling assembly.

The present invention also relates to a storage system suitable for a storage silo. The storage system comprises a silo storage structure comprising a plurality of storage pens, wherein each storage pens is arranged to accommodate a vertical stack of storage silos and a remotely operated vehicle according to any of the above-described embodiments.

In the following description, specific details are introduced to provide a thorough understanding of the embodiments of the claimed carrier and storage system. However, one skilled in the art will recognize that these embodiments can be practiced without one or more of the specific details, or with other components, systems, etc. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring aspects of the disclosed embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a perspective view of a prior art storage system including a grid and a plurality of remotely operated vehicles/robots;

FIG2 is a perspective view from above of a remotely operated vehicle according to one embodiment of the present invention;

FIG3 is a perspective view of the carrier in FIG2 as seen from below;

FIG4 is a cross-sectional view of the carrier of FIG2 and FIG3 , viewed along one principal orientation of the carrier;

FIG5 is a perspective view from above of a storage system according to one embodiment of the present invention, wherein a carrier of the present invention is shown arranged directly above five adjacent storage pens;

6A and 6B are cross-sectional views of the storage system of FIG. 5 , illustrating the carrier of the present invention above adjacent columns along two primary directions of the carrier;

FIG7 is a perspective view of a rolling assembly constituting a portion of a carrier according to one embodiment of the present invention;

8A and 8B are perspective views of rollers constituting part of a carrier according to one embodiment of the present invention; and

Figures 9A, 9B and 9C illustrate the rolling assembly of Figure 7 with one of the rollers removed, wherein Figures 9A and 9B are cross-sectional views of the rolling assembly as seen along each major orientation of the carrier, and Figure 9C is a perspective side view of a portion of the rolling assembly with the rollers removed.

DETAILED DESCRIPTION

All relative terms (such as above, below, sideways, vertical, X-axis direction, Y-axis direction, Z-axis direction, etc.) used to describe the vehicle (hereinafter referred to as the robot) of the present invention should be interpreted using the above-mentioned prior art storage system (Figure 1) as a reference system. For clarity, the X-axis direction, Y-axis direction, and Z-axis direction are described using the Cartesian coordinate system 100 in Figures 1 to 7 and 9.

Figures 2 and 3 show two different angles of a robot 1 comprising a rectangular carrier body or frame 4, which shows: a cavity centrally located within the rectangular carrier body or frame; a top cover 72 covering the top of the carrier body 4; a first carrier rolling mechanism 10 comprising four X-axis rollers 101 to 104 that move in the X-axis direction on support rails 13 of an underlying bin storage grid 15; and a second carrier rolling mechanism 11 comprising four Y-axis rollers that move in the Y-axis direction on support rails 13 of the underlying bin storage grid 15, with both first rolling mechanism 10 and second rolling mechanism 11 being mounted on the outer wall of the carrier body 4. The cavity within the robot 1 (Figure 3) is sized to contain at least a substantial portion, and most preferably an entire bin, of the largest bin 2 intended to be picked up by the robot 1. Picking up a bin 2 is performed by a lifting mechanism 7, which is shown in a retracted position at the top of the cavity in Figure 3.

FIG. 4 illustrates a cross section of the robot 1 when viewed along the X-axis direction.

Figures 5 and 6 illustrate a portion of a storage system 3, in which robots 1 are arranged in various adjacent positions atop a warehouse storage grid 15. In four of the five positions, the robots 1 are positioned directly above a storage column of the grid 15. As is apparent in Figures 6A and 6B, which illustrate the storage system 3 of Figure 5 in cross-sectional views along the Y-axis and X-axis, respectively, the robots 1 are sized so that their maximum cross-sectional area along the X-Y plane does not exceed the cross-sectional area of the corresponding (underlying) storage column. Thus, two or more robots 1 can operate simultaneously above adjacent columns of the grid 15, freeing up more space than in prior art systems.

One side of the first carrier rolling means 10 is shown in a perspective side view in FIG7 . In this particular embodiment of the invention, the rolling means 10 comprises two rollers 101, 102 having outer rims/edges 9, which are located near the corners of the carrier body 4 along the X-axis. A cover plate 25, which forms part of the carrier body 4, is arranged between the two rollers 101, 102.

Further details of one of these rollers 101, 102 are provided in Figures 8A and 8B, showing the outer and inner sides, respectively. In Figure 8B, a rotary encoder 23 of the optical rotary quadrature encoder type has been arranged within the inner diameter surface of the outer rim 9. Other types of encoders can be used, such as magnetic encoders, linear encoders, voltage-based analog encoders, etc. The rotor 5, shown in Figure 8B as a set of permanent magnets 5, is arranged within the circumference established by the rotary encoder 23, that is, closer to the axis of rotation of the roller 101.

The corresponding stator 19 is visible in Figure 9 in the form of electrical windings 19a wrapped around a yoke 19b. However, those skilled in the art will appreciate that the stator 19 and rotor 5 may (in other embodiments of the invention) be configured with stator magnets and rotor yokes/windings respectively.

9B and 9C also illustrate that the means 24 for measuring acceleration, for example by using piezoelectric sensors, is connected in signal communication with the stator 19 of each roller 101, 102. FIG9A is a cross-section of a portion of the first carrier rolling means 10 as viewed along the X-axis, showing the stator 19 enclosed by the outer rim 9.

All elements and the interaction/configuration of these elements may also be valid for the second carrier rolling means 11 .

The fact that the driving means are arranged near or within the rolling means 10 , 11 of the robot 1 helps to free up space on the storage system during operation, allowing a more compact design of the robot 1 compared to prior art robots.

All operations of the robot 1 are controlled by wireless communication means and a remote control unit, including one or more of the robot's motion control, the carrier lifting device 7 control, and the measurement of the robot's position, velocity, and acceleration.

In the foregoing description, various aspects of the carrier and storage system according to the present invention have been described with reference to illustrative embodiments. For illustrative purposes, the system and configurations have been described to provide a thorough understanding of the system and its operation. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiments, as well as other embodiments of the system, that are apparent to those skilled in the art are considered to be within the scope of the present invention.

List of symbol descriptions:

1 Vehicle/Robot

2 storage boxes

3 Storage System

4 Rectangular vehicle body/frame

5 Rotor/Permanent Magnet

7 Lifting device

9 Outer rim/edge of rolling means

10 First carrier rolling means/first unit roller

11 Second carrier rolling means/second unit roller

13 Support rails

15 Storage Grid

19 stator

19a Electrical winding

19b Yoke

23 Rotary encoder

24 Means of measuring acceleration

25 Cover

50 Bin lifting device

60 delivery stations/ports

72 Top Cover

100 Cartesian coordinate system

101 First X-axis roller

102 Second X-axis roller

103 Third X-axis roller

104 Fourth X-axis roller

111 First Y-axis roller

112 Second Y-axis roller

113 Third Y-axis roller

114 Fourth Y-axis roller

Claims (15)

1. A remotely operated vehicle (1) for retrieving a storage bin (2) from a self-lowering storage system (3), comprising: A vehicle lifting device (7) is used to lift the storage bin (2) from the underlying storage system (3); A first vehicle rolling means (10) includes a first rolling assembly (101-102) and a second rolling assembly (103-104) disposed on opposite sidewalls of a vehicle body (4), allowing the vehicle (1) to move along a first direction (X) on the underlying storage system (3) during use; and A second vehicle rolling means (11) includes a first rolling unit (111-112) and a second rolling unit (113-114) arranged on opposite sidewalls of the vehicle body (4), allowing the vehicle (1) to move along a second direction (Y) on the underlying storage system (3) during use, the second direction (Y) being perpendicular to the first direction (X); Each of these rolling units contains at least two rollers (101-104, 111-114); The vehicle (1) further includes: Motor control electronics are configured to supply power to the first vehicle rolling means (10) and the second vehicle rolling means (11). The vehicle (1) is characterized in that it further comprises: A first drive means is located or at least partially within the first vehicle rolling means (10) to provide a rolling unit-specific driving force to the vehicle (1) in the first direction (X); A second drive means, located or at least partially within the second vehicle rolling means (11), to provide a rolling unit-specific driving force to the vehicle (1) in the second direction (Y); and The motor control electronics are arranged within the volume between the rollers of each rolling unit (101-104, 111-114). 2. The vehicle (1) as claimed in claim 1, wherein at least one of the first driving means and the second driving means comprises an electric motor using a permanent magnet. 3. The vehicle (1) as claimed in claim 1 or 2, characterized in that at least one of the first driving means and the second driving means includes a rotor magnet disposed on the inner surface of the outer periphery (9) of the first vehicle rolling means and the second vehicle rolling means. 4. The vehicle (1) as claimed in claim 3, wherein at least one of the first driving means and the second driving means comprises a stator, the stator being at least partially arranged in the same plane of rotation as the first vehicle rolling means and the second vehicle rolling means and at least partially within the vehicle body (4). 5. The vehicle (1) as described in claim 1 or 2, characterized in that, At least one of the first driving means and the second driving means includes an electric motor, the electric motor including a rotor and a stator, and the carrier (1) further includes: The means for measuring back electromotive force communicates with one of the stator and the rotor, allowing the rolling mill of the carrier (1) to be aligned at a specific speed during operation. 6. The vehicle (1) as claimed in claim 1 or 2, characterized in that the vehicle (1) includes a rotary encoder (23) connected to at least one of the first vehicle rolling means and the second vehicle rolling means (10, 11), allowing angular position feedback during operation. 7. The carrier (1) as claimed in claim 6, wherein the rotary encoder (23) is an optical encoder type. 8. The vehicle (1) as claimed in claim 7, wherein the rotary encoder (23) is a rotary encoder disk arranged within the outer periphery (9) of at least one of the first vehicle rolling means and the second vehicle rolling means (10, 11). 9. The vehicle (1) as claimed in claim 1 or 2, characterized in that, At least one of the first driving means and the second driving means includes an electric motor, the electric motor including a rotor and a stator and The vehicle (1) further includes means for measuring the acceleration of at least one of the first vehicle rolling means and the second vehicle rolling means (10, 11), the means being in communication with the stator signal. 10. The vehicle (1) as claimed in claim 9, wherein the means for measuring acceleration comprises at least one of a piezoelectric sensor and a sensing sensor. 11. The vehicle (1) as claimed in claim 1 or 2, characterized in that, The first vehicle rolling means (10) includes four X-axis rollers (101-104), which have a rotational direction in the first direction and The second vehicle rolling means (11) includes four Y-axis rollers (111-114), which have a rotation direction in the second direction; Each of these X-axis rollers and each of these Y-axis rollers are respectively driven to the first drive means and the second drive means. 12. The carrier (1) as claimed in claim 11, characterized in that each of the four X-axis rollers and the four Y-axis rollers has: a plurality of rotor magnets arranged within the inner diameter surface of the outer periphery (9) of the roller; and a plurality of stator magnetic field windings (19a) arranged at least partially within the carrier body (4). 13. The carrier (1) as claimed in claim 12, characterized in that the stator magnetic field windings (19a) follow the outer periphery (9) of the four X-axis rollers and the four Y-axis rollers. 14. The vehicle (1) as claimed in claim 13, wherein for each of the four X-axis rollers and the four Y-axis rollers, at least a portion of the first driving means and the second driving means are arranged within the outer periphery (9) of the roller. 15. A storage system (3) for a storage bin (2), characterized in that it comprises: - A single-warehouse storage structure (15) includes multiple storage compartments, among which Each storage compartment (8, 8a, 8b) is arranged to accommodate a vertical stack of storage bins (2), and - A remotely operated vehicle (1) as described in any one of claims 1 to 14 is arranged on top of the storage structure (15).