EP4622906A1

EP4622906A1 - Vehicle

Info

Publication number: EP4622906A1
Application number: EP23813655.0A
Authority: EP
Inventors: Oliver KIRKBY; Leslie Wynn; Gaurav Mehta
Original assignee: Ocado Innovation Ltd
Current assignee: Ocado Innovation Ltd
Priority date: 2022-11-25
Filing date: 2023-11-24
Publication date: 2025-10-01
Also published as: KR20250111356A; JP2025538612A; CN120202162A; AU2023385517A1; WO2024110652A1

Abstract

There is provided a controller for an autonomous guided vehicle (AGV) such that an AGV can be operated in a semi-autonomous mode when coupled to an AGV controller. In this semi-autonomous mode, an operator can access all of the functionality of the AGV via the AGV controller. The AGV controller may be detached from the AGV and the AGV can revert to autonomous operation.

Description

VEHICLE

The disclosure relates to a vehicle, and in particular to a semi-autonomous guided vehicle which can be operated in a storage facility, such as a warehouse or fulfilment centre, for example.

Introduction

There is a trend towards the use of automated storage and retrieval systems (ASRSs) in order to provide goods to customers who have ordered goods online An ASRS can be used to store product so that it can then be packed and shipped to a customer. An example of such an ASRS is disclosed in the Applicant’s patent application WO 2015/019055. The level of automation within an ASRS can be increased by the use of robotic picking arms, such as is disclosed in WO 2023/285487. Another role for automation is the utilisation of autonomous vehicles, such as that disclosed by the Applicant’s co-pending application GB2217719.0 which relates to an autonomous pallet mover. It has been observed that there are situations in which such autonomous vehicles provide decreased efficiency, for example where there are many pallets packed tightly together, such as in a confined space.

Summary of the Invention

According to a first aspect of the present disclosure there is provided a controller for an autonomous guided vehicle, the controller comprising an coupling configured, in use, to couple to an autonomous vehicle and an interface for controlling the operation of the autonomous vehicle. The controller may further comprise rolling means. The controller may comprise drive means operable to actuate the rolling means. The controller may further comprise a wireless network interface.

According to a second aspect of the present disclosure there is provided a semi- autonomous vehicle comprising an autonomous guided vehicle and a controller for an autonomous guided vehicle as described above wherein the autonomous guided vehicle comprises an aperture configured to receive the coupling of the controller such that, in use, the controller interface is used to control the autonomous guided vehicle. The provision of such an AGV controller enables an operator to take control of an AGV to enable more efficient operation of the vehicle in environments in which it has been observed that AGVs can experience difficulties, for example confined spaces in which multiple pallets are arranged in a closely packed manner and/or next to walls or other structures.

The autonomous guided vehicle may comprise a control system such that, in use, the control system responds to control signals generated by the controller interface. The autonomous guided vehicle may comprise a drive system such that, in use, the drive system is actuated in response to control signals generated by the controller interface. The autonomous guided vehicle may also comprise a fork lift mechanism such that, in use, the fork lift mechanism is actuated in response to control signals generated by the controller interface.

According to a third aspect of the present disclosure, there is provided a method of operating an autonomous guided vehicle within a storage facility, the method comprising the steps of: a) coupling a controller for an autonomous guided vehicle to an autonomous guided vehicle to form a semi-autonomous vehicle; b) controlling the semi-autonomous vehicle via the controller to perform a task; c) decoupling the controller from the semi-autonomous vehicle; d) the autonomous guided vehicle moving autonomously to a first predetermined location within the storage facility.

In step d) the autonomous guided vehicle may carry a load to the first predetermined location. The method may comprise the further step of e) the autonomous guided vehicle depositing the load at the first predetermined location and then moving to a second predetermined location. In step b) the semi-autonomous vehicle may be controlled to move the semi-autonomous vehicle to a storage location to retrieve a load.

According to a fourth aspect of the present disclosure, there is provided a storage facility comprising a first zone and a second zone, in which the first zone is reserved for use by one or more autonomous guided vehicles and the second zone is reserved for use by one or more controllers for autonomous guided vehicles as described above and one or more semi-autonomous vehicles as described above. The separation of a storage facility into such zones assists in separating AGVs from human operators. Such a separation may enable AGVs to operate at increased speeds as the risk of a collision with a human operator is decreased, leading to increased system efficiency. Such a separation should also increase the welfare of the human operators.

A handover location may be defined adjacent to the first zone and a second zone. The storage facility may comprise a physical barrier to separate the first zone from the second zone. The physical barrier may comprise one or more apertures through which an autonomous guided vehicle or a semi-autonomous vehicle may pass. A handover location may be defined adjacent to one or each of the barrier apertures. The first zone may be contiguous with the second zone. Alternatively, the first zone may have an overlap region with the second zone.

Description of Drawings

Further features and aspects of the present invention will be apparent from the following detailed description of an illustrative embodiment made with reference to the drawings, in which:

Figure 1 shows a schematic depiction of a controller for an autonomous guided vehicle approaching an autonomous guided vehicle;

Figure 2 shows a schematic depiction of an autonomous guided vehicle when coupled to a controller;

Figure 3 shows a schematic depiction of a further example of a controller for an autonomous guided vehicle approaching an autonomous guided vehicles;

Figure 4 shows a schematic depiction of an autonomous guided vehicle when coupled to the controller shown in Figure 3;

Figure 5 shows a schematic depiction of a storage facility in which autonomous guided vehicles and controllers for AGVs may be used;

Figure 6 shows a schematic depiction of a further example of a storage facility in which autonomous guided vehicles and controllers for AGVs may be used; Figure 7 shows a depiction of a flowchart describing the operation of an autonomous guided vehicles with an AGV controller;

Figure 8 shows a schematic depiction of a first example of an autonomous pallet mover approaching a pallet;

Figures 9 (a) to (g) are schematic depictions of the autonomous pallet mover of Figure 8;

Figure 10 is a schematic depiction of a second example of an autonomous pallet mover;

Figures 11 (a) to (c) are schematic depictions of the autonomous pallet mover of Figure 10;

Figure 12 is a block diagram showing the main components of an autonomous pallet mover;

Figure 13 is a flow diagram showing an example of the steps an autonomous pallet mover undertakes when engaging with a pallet; and

Figure 14 (a) to (e) are schematic depictions showing the steps undertaken by an autonomous pallet mover according to the second example.

Detailed Description

Figure 1 shows a schematic depiction of a controller 200 for an autonomous guided vehicle 1. In the example shown in Figure 1 the autonomous guided vehicle (henceforward AGV) comprises a plurality of forks 4 and is designed to lift and move pallets 20. As will become apparent from the following discussion, the exact nature of the AGV is not key to the present disclosure. The AGV 1 is capable of sliding the plurality of forks 4 into the body of a pallet 20, lifting the pallet, moving the pallet to a specific location and then depositing the pallet at that location. The structure and function of the AGV are described below with reference to Figures 8 to 14.

The AGV additionally comprises an aperture 50 which is configured to engage with a coupling 220 of the AGV controller 200. The AGV controller 200 further comprises an interface 210 and rolling means 230. In operation, the AGV controller can be manually manoeuvred into a position adjacent to an AGV and the AGV controller coupling 220 can be inserted into the AGV aperture 50. The coupling of the AGV controller and the AGV causes the autonomous functionality of the AGV to be over-ridden such that the AGV may be operated by an operator, through the manipulation of the controller interface 210. For ease of operation, the controller interface may resemble the interface of a conventional manual vehicle, for example a hand truck or pallet lifter such as may be found in a storage facility. When coupled together, the AGV and the AGV controller can be considered to be a semi-autonomous guided vehicle 201 (henceforth SAGV).

In the example shown in Figures 1 and 2 the controller interface comprises a yoke 212 and a plurality of triggers 214. Figures 3 and 4 show a second example of an AGV controller in which the AGV interface 210 comprises a steering wheel 216. It should be understood that the AGV interface 210 may comprise further controls, actuators, etc. These may be physical controls such as switches, dials, etc. and/or may comprise GUI elements on a touchscreen which can be selected and/or activated by an operator.

Figure 5 shows a schematic depiction of a storage facility 400 in which AGVs 1 , AGV controllers 200 and SAGVs 201 are used to transport pallets. The storage facility comprises a manual operations area 410, autonomous operations area 420 and a plurality of storage areas 430. The plurality of storage areas 430 may be located within the manual operations area 410 or alternatively the plurality of storage areas 430 may be located adjacent to the manual operations area 410 such that the plurality of storage areas can be accessed from the manual operations area.

It can be seen from Figure 5 there is an overlap between the manual operations area 410 and the autonomous operations area 420. It should be understood that in an alternative configuration the manual operations area and the autonomous operations area may be contiguous. In use, a central computing system 450 instructs one of the AGVs 1 to move from its current position (which is likely to be within the autonomous operations area) to a position within the manual zone. In one example, the AGV will move to the edge of the manual zone such that an operator may move an AGV controller to a position adjacent to the AGV. The AGV controller may then be mated to the AGV to form a SAGV. The operator can then move the SAGV into one of the plurality of storage areas and manipulate the SAGV to lift and retrieve a pallet which is stored within the storage area. The operator can then move the SAGV to the edge of the autonomous operations area and cause the AGV controller to disengage from the AGV. The AGV can then perform one or more autonomous actions. For example, the central computing system may communicate a location in the autonomous operations area to the AGV. The AGV will then move autonomously to this location. The location may be adjacent to one of a plurality of stations 422 which are located within the autonomous operations area. The stations may be decant stations which are used to decant product items from the pallets such that they can be inducted into an automated storage and retrieval system. This decant function may be performed by human operators, by robotic picking arms, or by a combination of the two. Once all of the product items have been removed from the pallet then the AGV may deposit the empty pallet at a pallet storage location. Once the AGV has disposed of the pallet then it may return to the manual zone so that the AGV can be attached to a further AGV controller in order to complete a further task.

In an alternative arrangement, an AGV may deposit a loaded pallet adjacent to one of the stations 422 and then return to the manual zone in order to complete a further task as a SAGV. A further AGV may be used autonomously to retrieve empty pallets from locations adjacent to one of the stations and to then deposit them at a pallet storage location.

In use, the central computing system may instruct one of the AGVs to move to one of a number of predetermined handover locations such that an operator may couple an AGV controller to it. Similarly, the central computing system may send a message to an operator to instruct the operator to move to one of the handover locations where an AGV may be waiting to have an AGV controller coupled to it. Once an SAGV has been loaded with a pallet from one of the truck trailers then an operator may move the SAGV to the nearest handover location before detaching the AGV controller, causing the AGV to be handed over to autonomous operation. In an alternative, the central computing system may send a message to an operator instructing them to move an SAGV to a specified handover location before detaching the AGV controller from the AGV. Figure 6 shows a schematic depiction of a further example of a storage facility as described above with reference to Figure 5. In this example, the plurality of storage areas 430 comprises a plurality of truck trailers. It is common for truck trailers to hold a plurality of tightly arranged pallets, each of the pallets storing boxes or containers of product items. It has been found that the tight packing of the pallets, in conjunction with the confined space of the interior of the truck trailer, makes it difficult for AGVs to efficiently remove pallets from such a location. Figure 6 also depicts the use of a physical barrier 415 which provides a separation between the manual operations area and the autonomous operations area. The physical barrier 415 may comprise gaps 417 through which an AGV can pass. One or more predetermined handover locations may be defined at, or near to, barrier gaps 417.

Figure 7 shows a depiction of a flowchart in which at step S700 an AGV controller is attached to an AGV to form a SAGV. The SAGV us then used to perform a task (S710, for example the retrieval of a load from a storage location) before the SAGV is moved to the autonomous zone (S720). The operator will then detach the AGV controller, causing the AGV to revert to autonomous operation. The AGV will then perform a task autonomously (S740, for example, moving the pallet to a station for decant activities) before returning to the manual zone (S750). Once the AGV has returned to the manual zone then it may be attached to a controller, such that the method returns to step S700. It should be understood that an AGV may repeat multiple instances of the method until there are no further loads in the storage area(s). An AGV may pause the execution of the method after step S740 if the AGV determines that it has insufficient battery charge to perform a further instance of the method. The AGV may then move to a re-charging station and then recommence the method at step S750 once the AGV has been fully re-charged (or until an appropriate level of charge has been achieved).

The AGV controllers shown in Figures 1 to 4 may take a wide range of forms. For example, the AGV controller may have no motive power such that the operator has to manually move the SAGV. In an alternative, the connection between the AGV controller and the AGV may cause the control system of the AGV to actuate the drive assembly and/or the fork lifting mechanism of the AGV in response to the action of the operator on the AGV interface 210. Additionally, or as a further alternative, the AGV controller may comprise drive means operative to drive the rolling means 230 of the AGV controller (for example one or more electric motors), such that the rolling means assist or replace the physical efforts of the operator. The AGV controller may comprise a power source, for example a battery, or the power for the AGV controller drive means may be supplied from the AGV. The AGV controller may comprise a platform 250 upon which an operator may stand when operating a SAGV (or the AGV controller when the AGV controller is capable of powered movement). The platform 250 may be folded out of the way (for example into a vertical orientation, as is shown in Figure 4) when the AGV controller is being moved manually.

The coupling between the AGV controller and the AGV may be solely mechanical. As an alternative, the coupling may be electro-mechanical such that manipulations of the AGV controller interface 210 by the operator cause one or more of the drive assembly, fork lifting mechanism or other sub-system of the AGV to be actuated. If the coupling is only mechanical then a wireless connection may be made between the AGV controller and the AGV, such that movements of the AGV controller cause elements of the AGV to be actuated. The AGV elements may be directly controlled by the AGV controller interface or the movements of the AGV controller interface may be an input to the AGV control elements, which then controls the AGV elements accordingly. The AGV controller may comprise a display screen which can be used to provide feedback to the operator on the status and operation of the AGV controller (or the SAGV when the AGV controller is attached to an AGV). The display screen may be used to display messages which are transmitted by the central computing system. It will be understood that in such a case, the AGV controller will comprise a wireless network interface, such as for example WiFi, to enable communications with the central computing system. In addition, or as an alternative, messages may be sent to an operator device, for example a hand held device, smartwatch etc. to instruct the operator of a destination for an AGV controller (or a SAGV). The AGV controller may comprise a mounting device which can hold a handheld device such as, for example, a smartphone or a tablet computer such that the operator can view the device whilst operating an AGV controller (or a SAGV).

Figures 1 to 4 show examples of the types of controller interface that may be used. It should be understood that other forms of controller interface are possible. It is thought beneficial that the controller interface closely resembles the interfaces of commonly used manual load-bearing vehicles in order to allow operators to efficiently transition from conventional vehicles to the SAGVs of the present disclosure. It should be understood that in an alternative, the controller interface may comprise a trackball or joystick, either as a replacement to the controller interfaces shown in Figures 1 to 4, or as an augmentation to those controller interfaces . In addition, or as a further alternative, part or all of the controller interface may be provided using a graphical user interface of an AGV controller display screen, or similar display screen.

It should be understood that although the following discussion describes a pallet moving AGV, it will be understood that the concept of an ABV controller than can be coupled to an AGV to provide a semi-autonomous guided vehicle is applicable to all manner of AGVs, regardless of their function.

An example of an autonomous guided vehicle 1 which operates as a AGV is shown in Figure 8 and comprises a main body 2 comprising a drive assembly (not shown) for moving the AGV on the floor, a steering mechanism (not shown) for manoeuvring the AGV 1 and a lifting mechanism (not shown) for raising and lower the plurality of forks 4 extending from the main body 2. In the particular example shown in Figure 8, the AGV 1 comprises two forks defining a left fork 6 and a right fork 8. The first 10 and second 12 sets of wheels are mounted to the left 6 and right 8 forks in the sense that half of the wheels of the first 10 and second 12 sets of wheels are mounted to the left forks 6 and the other half of the wheels of the first 10 and second 12 sets of wheels are mounted to the right fork 8. For ease of explanation, each set of the first and second sets of wheels 10, 12 comprise a first wheel 14 and a second wheel 16. The first wheel 14 and second wheel 16 of each of the first and second sets of wheels 10, 12 are shown mounted to respective left and right forks 6, 8 of the AGV 1 .

The first and second sets of wheels 10, 12 are shown rotatably mounted on the inside of the forks 4 but other means to rotatably mount the first and second sets of wheels 10, 12 to the plurality of forks 4 in order for the plurality of forks 4 to move on the floor are permissible in the present invention. The number of forks is not limited to two forks and can include any number of forks, e.g. a pallet mover3 with triple forks. To be able to move in a vertical direction, each wheel of the first and second sets of wheels 10, 12 can be pivotably mounted to the plurality of forks 4. For example, each wheel of the first and second sets of wheels 10, 12 can be mounted to levers (not shown) pivotally mounted to the plurality of forks 4 that retract in a vertical direction to retract each wheel towards the inside of their respective fork and thereby, disengage from the floor and extend outwardly of their respective fork in the deployed position to engage with the floor. However, other means to mount each set of the first and second sets of wheels 10, 12 to enable vertical movement relative to the plurality of forks 4 is permissible in the present invention. An actuation mechanism (not shown) coupled to the first and second sets of wheels 10, 12 is configured to independently move each set of the first and second sets of wheels in the vertical direction. Further detail of the actuation mechanism is discussed below.

Connected to the plurality of forks is the lifting mechanism (not shown) for raising and lowering the plurality of forks. Various lifting mechanisms commonly known in the art can be used to raise and lower the plurality of the forks. These include but is not limited to a hydraulic pump, electric motor etc. Typically, the plurality of forks are connected to a frame forming the main body of the AGV and the lifting mechanism is connected to the plurality of forks and the frame such that the lifting mechanism is configured to raise and lower the frame and the plurality of forks. The lifting mechanism can cooperate with the first or the second set of wheels to raise or lower the plurality of forks. For example the plurality of forks can be raised by lowering the first or second sets of wheels. The first set of wheels can be mounted on levers attached to linkages that go to levers attached to the hydraulic pump in the main body of the AGV that lowers the first or second set of wheels so as to raise the plurality of forks. As the first set of wheels may be primarily the load bearing wheels, the first set of wheels can be lowered to raise the plurality of forks. The lower the first set of wheels relative to the plurality of forks, the higher the plurality of forks is raised. Alternatively, the lifting mechanism for raising the plurality of forks can be separate to the first and second sets of wheels. However, the first or second set of wheels lowers as the plurality of forks are lifted. A locking mechanism locks the first or second set of wheels in the lowered positioned when the plurality of forks is in the raised position so as to raise a pallet engaged with the plurality of forks off the ground. A drive assembly (not shown) comprising one or more drive wheels propels the AGV on the floor. The drive assembly comprises a drive mechanism, e.g. drive motor, for driving rotation of one or more drive wheels about a drive axis. The drive assembly is located at the rear of the AGV within the main body. The drive wheel for propelling the AGV on the floor can be connected to a steering mechanism (not shown) for manoeuvring the AGV on the floor. The steering mechanism can be configured to rotate the one or more of the drive wheels about a steering axis that is substantially perpendicular to their drive axis to change direction of the AGV on the floor. Various steering mechanisms known in the art can be used to change direction of the AGV. These include but is not limited to a steering driving unit coupled to the one or more drive wheels that is configured to rotate one or more of the drive wheels about the steering axis. For example, the main body of the AGV may include swivel casters located at four corners of the main body of the AGV. The drive wheel and steering wheels respectively propels and changes direction of the main body of the AGV. The steering mechanism can be separate to the drive assembly in the sense that a separate steering wheel can be used to change direction of the AGV independent to propelling the AGV by the drive assembly.

The AGV comprises a guidance system (not shown) coupled to the drive assembly and steering mechanism to control the movement of the AGV on the shop floor. The guidance system may include but is not limited to wire guidance, laser guidance, magnetic tape guidance, odometry guidance, inertial guidance or optional guidance. For example, laser guidance systems use special markers that the AGV senses and uses to control its travel. The guidance system is controlled by a control system comprising a controller, e.g. processor and a memory storage device for storing instructions executed by the controller for controlling the operation of the AGV. The memory storage device can be any storage device commonly known in the art and include but is not limited to RAM, computer readable medium, magnetic storage medium, optical storage medium or other electronic storage medium which can be used to store data and accessed by the controller. Controlling the operation of the AGV include but is not limited to controlling the drive assembly and the steering mechanism in response to signals from the guidance system to control the travel of the AGV; controlling the vertical movement of the first and second sets of wheels mounted to the plurality of forks to engage with a pallet and controlling the lifting mechanism to raise and lower a pallet.

To engage the plurality of forks 4 with the pallet 18, the control system in cooperation with the actuation mechanism and drive mechanism is configured to move the AGV so as to fully engage with the pallet. The term “fully” engage the plurality of forks with the pallet is used to describe the condition where the plurality of forks are inserted within the pallet so that it can be lifted off the floor. The actuation mechanism can comprise a linear actuator to move each of the first and second sets of wheels in a vertical direction via one or more linkages. The control system can be configured to actuate the actuation mechanism to independently move the first and the second set of wheels in the vertical direction. For example, the actuation mechanism can comprise a first linear actuator for raising and lowering the first set of wheels and a second linear actuator for raising and lowering the second set of wheels. To independently move the first set of wheels and the second set of wheels in the vertical direction, the control system can be configured to independently actuate the first linear actuator to deploy or retract the first set of wheels and the second linear actuator to deploy or retract the second set of wheels. Alternatively or in combination with the linear actuator, the actuation mechanism can comprise a cam mechanism comprising one or more cams and a cam follower moveable along the one or more cams to move the cam follower from a raised position to retract the first and/or second sets of wheels and a lowered position to deploy the first and/or second sets of wheels.

Figures 9a to g are schematic drawings showing the stages the plurality of the forks 4 engaging with the pallet 18. The engagement operation involves independently retracting and deploying the first and second set of wheels 10, 12 in a predetermined sequence in conjunction with driving the AGV 1 towards the pallet 18. The operation begins with retracting the first set of wheels 10 proximal the distal end of the plurality of forks 4 (i.e. front set of wheels) so as to allow the front portion of the plurality of forks 4 to be inserted into the opening provided by the space between the upper 20 and lower 22 decks of the pallet 18. In Figure 9b, the AGV 1 moves a first distance Li towards the pallet 18 so that the front portion of the plurality of forks 4 clears a plank or runner 24 in the lower deck 22 of the pallet 18. The first distance is dependent on the spacing between the first and second sets of wheels 10, 12. In this particular example, the first distance is sufficient to step over a single plank 24 in the lower deck 22 of the pallet 18 without the second set of wheels 12 proximal to the main body 2 of the AGV 1 physically riding or bumping over the single plank as shown in Figure 9b. The first distance Li can be a predetermined distance applicable to a type of pallet stored in the memory storage device and can be dependent on the width of one or more planks 24 in the lower deck 22 of the pallet 18. Once the AGV 1 has moved the first distance Li towards the pallet 18 so that the front portion of the plurality of forks 4 enters the pallet 18, the engagement operation proceeds with the deploying the first set of wheels 10 into engagement with the floor followed by retracting the second set of wheels 12 as shown in Figure 2c. Deploying the first set of wheels 10 prior to retracting the second set of wheels 12 maintains the stability of the AGV 1 and prevent it from tipping when the second set of wheels 12 are retracted. This enables the AGV 1 to move a second distance L2 towards the pallet 18 to cause the plurality of forks 4 to be inserted further into the pallet 18 as shown in Figure 9d. Like the first distance, the second distance can be a predetermined distance applicable to a type of pallet that is stored in the memory storage device. The predetermined sequence of operations of; (i) retracting the first set of wheels, (ii) moving the AGV a first distance towards the pallet; (iii) deploying the first set of wheels and retracting the second set of wheels; (iii) moving the AGV a second distance towards the pallet; repeats when stepping over a second plank in the lower deck of the pallet as shown in Figure 9e and 9f. As there are typically three planks or runners 24 in the lower deck of the pallet, once the first and second set of wheels have cleared the first and second planks, the plurality of forks are considered to have fully engaged with the pallet as shown in Figure 2f. Once the plurality of forks are fully engaged with the pallet, the next operation would be to lift the pallet 18 off the floor as shown in Figure 9g so that it can be moved on the floor. Lifting the pallet 18 involves lowering or deploying the first set of wheels 10 relative to the plurality of forks by means of the actuation mechanism such that the plurality of forks 4 are raised. Alternatively, the plurality of forks is separately raised causing the first set of wheels 10 to lower so as to engage with the floor. A locking mechanism (not shown) locks the first set of wheels in the lowered or deployed position so as to lift the pallet engaged with the plurality of forks off the floor.

The first set of wheels 10 proximal the distal end of the plurality of forks 4 are load bearing wheels as these wheels bear the weight of the pallet 18 and any loads on the pallet when lifting the pallet off the ground. The second set of wheels 12 proximal to the main body 2 of the AGV 1 function as balancing wheels to prevent the AGV 1 from tipping when the first set of wheels 10 retract. This allows the first and second sets of wheels 10, 12 to step over one or more planks 24 in the lower deck 22 of the pallet 18 as shown in Figure 2(a to g). The spacing between the first and second sets of wheels 10, 12 is dependent on the number of planks 24 in the lower deck of the pallet 18 and the number of operations required for the first and second sets of wheels 10, 12 to step over the one or more planks 24 in the lower deck of the pallet when fully engaging with the pallet.

In a second example of an AGV 101 , as shown in Figure 10, the spacing, S, between the first and second sets of wheels 110, 112 is such that the plurality of forks 104 fully engage with the pallet 18 in a fewer number of operations than in example shown in Figure 8. In comparison to the first example shown in Figures 9a to g requiring multiple movements of the first and second sets of wheels 10, 12 to fully engage with the pallet 18, in the second example shown in Figure 10, a single operation is required for the AGV 101 to move the first distance Li towards the pallet 18 corresponding to the distance the first set of wheels 110 steps over two planks 24 in the lower deck 22 of the pallet 18, i.e. the first distance Li corresponds to the spacing between the two planks 24 in the lower deck of the pallet inclusive of the width of the two planks. Thus, the process of fully engaging with the pallet shown in Figure 4(a and b) begins with retracting the first set of wheels 110 so that they clear a first plank at the perimeter of the pallet 18 and inserting the plurality of forks into the pallet. Because the spacing between the first and the second sets of wheels is sufficiently large to clear or step over two spaced apart planks in the lower deck of the pallet, the plurality of forks 104 can be inserted further into the pallet so as to step over two planks in the lower deck of the pallet in a single movement operation.

To fully engage with the pallet 18, the first set of wheels 110 deploy and the second set of wheels 112 retract as shown in Figure 4b so as to allow the AGV to move a second distance L2 closer towards the pallet 18 as shown in Figure 4c. Once the plurality of forks are fully engaged with the pallet, the plurality of forks 104 can be raised to lift the pallet off the floor. Raising the plurality of forks can involve lowering or deploying the first set of wheels 110. Alternatively, the plurality of forks is independently raised causing the first set of wheels 110 to lower so as to engage with the floor. A locking mechanism (not shown) locks the first set of wheels in the lowered position so as to lift the pallet engaged with the plurality of forks off the floor.

The spacing S between the first and second set of wheels can be varied by varying the position of the first set of wheels 10, 110 relative to the second sets of wheels 12, 112. The closer the second set of wheels 12, 112 is to the main body 2, 102 of the AGV 1 , 101 without causing the AGV to tip when the first set of wheels 10, 110 are retracted, the greater the spacing between the first and second sets of wheels. Typically, the spacing S between first and second sets of wheels has to exceed 100 cm in order for the first set of wheels 110 to step over two planks in the lower deck of the pallet in a single movement operation.

To automate the independent movement of the first and second set of wheels when engaging with the pallet as shown in Figures 8 and 10, the AGV 1 , 101 comprises one or more proximity sensors to sense the presence of nearby obstacles or objects, in this case, the one or more planks in the lower deck of the pallet. Examples of proximity sensors to sense the presence of objects include but is not limited to LiDAR sensors comprising a laser beam source and an optical receiver, ultrasonic sensors. Other examples of sensing the presence of nearby object is use of one or more cameras or depth cameras for visualising the presence of nearby objects or obstacles. The proximity sensor or camera can be mounted to the plurality of forks, particularly at the distal end of one or more of the plurality of forks. Alternatively, the proximity sensor or the camera can be mounted to the main body of the AGV. The control system is coupled to the proximity sensor and/or camera and is configured to independently retract or deploy the first and second sets of wheels in response to one or more signals from the proximity sensor and/or camera.

Figure 12 is a simplified block diagram 30 showing the main components of the AGV for engagement with a pallet and Figure 13 is a flow diagram 1300 showing an example of the steps the AGV undertakes when engaging with the pallet. The main components of the AGV for engagement with a pallet can be summarised in Figure 12 to comprise an actuation mechanism 38 that is configured to move the first and second set of wheels in a vertical direction, a proximity sensor 44 to senses a nearby object, a drive assembly 40 to manoeuvre the AGV and a fork lifting mechanism 42 to raise and lower the plurality of forks. Each of the components for engagement with a pallet is controlled by a control system 32 comprising a controller 34, e.g. a processor, and a memory storage device 36 for storing instructions to be executed by the controller 34. For example, the instructions include actuating the actuation mechanism 38 to independently move the first and second set wheels in a vertical direction in response to one or more signals from the proximity sensor 44. In addition to these components, the AGV will further comprise a battery (or some other power source) to power the different components discussed above with reference to Figure 5. The AGV will comprise a interface such that a battery may be re-charged or the battery may be hot- swapped to enable continued AGV operation. The AGV further comprises a wireless interface to allow it to receive data from the central computing system and to send data back to the central computing system, for example status message, data logs, etc.

The steps in the engagement of the plurality of forks with the pallets can be summarised in the flowchart 1300 shown in Figure 13 in conjunction with Figure 12. The process begins S1302 with the proximity sensor detecting the presence of a plank in the lower deck of the pallet S1304. In response to detecting the presence of a plank, the controller 34 actuates the actuation mechanism 38 to retract the first set of wheels and deploy the second set of wheels S1306. This allows the AGV to move a first distance towards the pallet as the first set of wheels steps over the plank S1308. If, however, the AGV does not detect the presence of a pallet, the AGV is instructed to continue moving S1316 until a pallet is detected. To fully engage with the pallet, the controller 34 actuates the actuation mechanism 38 to deploy the first of wheels and retract the second set of wheels so as to allow the second set of wheels to step over the plank when the AGV moves a second distance towards the pallet S1312.

Depending on the spacing between the first and second sets of wheels, the next stage will determine whether the plurality of forks has fully engaged with the pallet S1314. In the case where the spacing between the first and second sets of wheels is relatively small (see Figure 8) necessitating that the first and second sets of wheels has to step over two planks in two sets of multiple operations or procedures (e.g. four operations) to fully engage with the pallet. After stepping over the first plank of the pallet, the controller 34 in response to one or more signals from the proximity sensor 44 is configured to actuate the actuation mechanism 38 to independently move the first and second sets of wheels to step over a second plank in the lower deck of the pallet. One set of operations or procedures to step over one or more planks in the lower deck of the pallet may involve:- i) retracting the first set of wheels and deploying the second set of wheels; ii) moving the AGV a first distance so as to insert a portion of the plurality of forks into the pallet and to step over a first plank in the lower deck of the pallet; iii) deploying the set of wheels and retracting the first set of wheels to stabilise the plurality of forks; iv) moving the AGV a second distance so as to insert an increased portion of the plurality of forks into the pallet;

As the spacing between the first and second sets of wheels is relatively small, the operation above (i) to (iv) is repeated for stepping over the second plank in the lower deck of the pallet. In the case where the spacing between the first and second sets of wheels is relatively large as shown in Figure 10, the plurality of forks fully engage with the pallet after stepping over two planks in the lower deck of the pallet in one set of operations ((i) to (iv)), i.e. movement of the plurality of forks along a first distance and a second distance. When approaching a pallet, the first and second sets of wheels may already be deployed, in which case step (i) may involve retracting the first set of wheels as the second set of wheels is already deployed so as to step over the plank in the lower deck of the pallet. Data associated with the type of plurality of forks which include the spacing between the first and second sets of wheels are stored in the memory storage device 36. The controller in cooperation with the memory storage device is able to determine the type of the plurality of forks when engaging with the pallet.

The frequency by which the first and second set of wheels would need to step over the one or more planks in the lower deck of the pallet in order for the plurality of forks to fully engage with the pallet will depend on the separation, S, between the first and second set of wheels along the plurality of forks. The closer the separation, S, between the first and second sets of wheels, the greater the number of times the first and second sets of wheels would need to step over the one or more planks in the lower deck of the pallet. In a second embodiment of the AGV 301 shown in Figures 14a to e, the second set of wheels 212 can be configured to be retractable longitudinally along the plurality of forks 204 to vary the separation between the first 210 (not shown) and second 210 sets of wheels rather than in the substantially vertical direction as in the first embodiment of the present invention discussed above with reference to Figures 1 to 6. Movement of the second set of wheels 212 along the axis, X-X, as shown in Figure 14(a) removes the need to have predetermined separations between the first and the second set of wheels and thus, removes the need for the second sets of wheels 212 to step over the one or more planks in the lower deck 22 of the pallet 18.

To ensure the stability of the AGV 201 when the first set of wheels 210 retract, the second set of wheels 212 remain engaged with the floor but retract in a longitudinal direction along the plurality of forks 204 when the second set of wheels 212 approaches the lower deck 22 of the pallet 18. Once inserted into the pallet 18, the lifting mechanism (not shown) is configured to extend or deploy the first set of wheels 210 relative to the plurality of forks 204 in a vertical direction to engage with the floor. Further extension of the first set of wheels 210 relative to the plurality of forks 204 raises the plurality of forks 204 and the pallet supported by the plurality of forks. In the particular example shown in Figure 14e, the second set of wheels 212 separates from the plurality of forks 204 to maintain the stability of the main body of the AGV 202 when the plurality of forks are raised. As shown in Figure 14 a to e, the second set of wheels 212 are mounted on a plurality of runners 216 that enable the second set of wheels to be retractable in a longitudinal direction parallel to the plurality of forks. The plurality of runners 216 are mounted to the main body 202 of the AGV such that when the plurality of forks are raised, the second set of wheels 212 separate from the plurality of forks as shown in Figure 14e.

Like the first embodiment of the present invention, the first and the second sets of wheels 210, 212 can be independently moveable relative to the plurality of forks 204. Independent movement of the first and second sets of wheels can be controlled by an actuating mechanism as discussed above. Movement of the second set of wheels 212 in a longitudinal direction from a forward position as shown in Figure 14(b) to a rearward position as shown in Figure 14(d) occurs when the second set of wheels approaches the lower deck 22 of the pallet 18. Various means can be used to move the second set of wheels 212 in the longitudinal (substantially horizontal direction) direction along the plurality of forks 204. One example, is the second set of wheels 212 can be resi I iently biased in the forward direction by a resilient member (e.g. spring) such that they are closer to the first set of wheels 210 in a resting position providing increased stability of the AGV 201 when the first set of wheels is in the retracted configuration vertically within the plurality of forks 204. The resilient member (not shown) is configured to retract the second set of wheels 212 in a longitudinal direction away from the first set of wheels when the bias of the resilient member is overcome. For example, the resiliency of the resilient member can be chosen such that the bias of the resilient member is overcome by the drive assembly (e.g. a motor) of the AGV. The second set of wheels 212 is arranged to butt up against the lower deck 22 of the pallet 18 when the plurality of forks 204 are initially inserted into the pallet (see Figure 14c). The bias is overcome by virtue of the drive assembly moving the pallet 18 and the plurality of forks into engagement with the pallet. In the particular example shown in Figures 14(a) to (e), the drive assembly comprises a drive wheel 214 rotatable about a drive axis for driving movement of the AGV on the floor. The mere driving action of the AGV towards the pallet may be sufficient to overcome the bias of the second set of wheels to retract away from the first set of wheels as the plurality of forks progressively engages with the pallet (see Figure 14d).

Instead of the second set of wheels butting up against the lower deck of the pallet, each wheel of the second set of wheels can be mounted to a cradle that is moveable in a longitudinal direction along its respective fork and is arranged to butt up against the lower deck when the plurality of forks enters the pallet. The use of a cradle to carry each of the second set of wheels mitigate the risk of the second set of wheels riding over the one or more of the planks in the lower deck of the pallet when the plurality of forks enters into the pallet. Alternatively, a drive mechanism in response from a signal from a suitable sensor (e.g. proximity sensor) can be configured to progressively retract the second set of wheels as the plurality of forks increasingly engage with the pallet. In all cases, the first set of wheels remain retracted until the plurality of forks are fully engaged with the pallet. The steps of engagement of the plurality of forks of AGV 201 according to the second embodiment of the present invention with a pallet 18 can now be described with reference to Figures 7(a to e). The position of the first 210 and second 212 sets of wheels relative to the plurality of forks 204 in a normal configuration is shown in Figure 14(a) and shows the first set of wheels 210 is in in the retracted position and the second set of wheels 212 in the forward position relative to the plurality of forks to maintain the stability of the AGV as the AGV moves on the floor. The second set of the wheels 212 is shown mounted to a cradle that is moveable in a longitudinal or axial direction, X-X. Also shown is the drive wheel 214 mounted to the main body 201 of the AGV 201 for moving the AGV. The second set of wheels 212 approaches the lower deck 22 of the pallet 18 as the plurality of forks 204 enters the pallet as shown in Figure 14(b). Further movement of the AGV 201 towards the pallet not only increases the proportion of the plurality of forks entering the pallet but cause the second set of wheels 212 to butt up against the lower deck 22 of the pallet 18, more specifically, a plank in the lower deck of the pallet as shown in Figure 14(c). This causes the second set of the wheels 212 to retract in a rearward direction away from the first set of wheels 210 as the plurality of forks are driven into the pallet as shown in Figure 14(d). Once the plurality of forks have fully engaged with the pallet as shown in Figure 14(e), the lifting mechanism is actuated to extend the first set of wheels 210 in a vertical direction to engage with the floor to stabilise the AGV on the floor as the plurality of forks are raised. Further extension or lowering of the first set of wheels raises the plurality of forks, which in turn raises the pallet off the floor. Like the first embodiment of the AGV, the lifting mechanism can comprise a hydraulic pump and/or electric motor which is coupled to the first sets of wheels by one or more levers to raise or lower the plurality of forks.

It will be understood that various changes, modification, alterations, and combination in the details, materials and arrangements of the parts and components that have been described and illustrated in order to explain the AGV controller as described herein may be made by those skilled in the art within the principle and scope of this disclosure.

According to an aspect there is provided a controller for an autonomous guided vehicle (AGV) such that an AGV can be operated in a semi-autonomous mode when coupled to an AGV controller. In this semi-autonomous mode, an operator can access all of the functionality of the AGV via the AGV controller. The AGV controller may be detached from the AGV and the AGV can revert to autonomous operation.

Claims

1. A controller for an autonomous guided vehicle, the controller comprising an coupling configured, in use, to couple to an autonomous vehicle and an interface for controlling the operation of the autonomous vehicle.

2. A controller according to claim 1 , the controller further comprising rolling means.

3. A controller according to claim 2, the controller further comprising drive means operable to actuate the rolling means.

4. A controller according to any of claims 1 to 3, the controller further comprising a wireless network interface.

5. A semi-autonomous vehicle comprising an autonomous guided vehicle and a controller for an autonomous guided vehicle according to any of claims 1 to 4 wherein the autonomous guided vehicle comprises an aperture configured to receive the coupling of the controller such that, in use, the controller interface is used to control the autonomous guided vehicle.

6. A semi-autonomous vehicle according to claim 5, wherein the autonomous guided vehicle further comprises a control system such that, in use, the control system responds to control signals generated by the controller interface.

7. A semi-autonomous vehicle according to claim 5 or claim 6, wherein the autonomous guided vehicle further comprises a drive system such that, in use, the drive system is actuated in response to control signals generated by the controller interface.

8. A semi-autonomous vehicle according to any of claims 5 to claim 7, wherein the autonomous guided vehicle further comprises a fork lift mechanism such that, in use, the fork lift mechanism is actuated in response to control signals generated by the controller interface.

9. A method of operating an autonomous guided vehicle within a storage facility, the method comprising the steps of: a) coupling a controller for an autonomous guided vehicle to an autonomous guided vehicle to form a semi-autonomous vehicle; b) controlling the semi-autonomous vehicle via the controller to perform a task; c) decoupling the controller from the semi-autonomous vehicle; d) the autonomous guided vehicle moving autonomously to a first predetermined location within the storage facility.

10. A method according to claim 9, wherein in step d) the autonomous guided vehicle carries a load to the first predetermined location.

11. A method according to claim 10, the method comprising the further step of e) the autonomous guided vehicle depositing the load at the first predetermined location and then moving to a second predetermined location.

12. A method according to any of claims 9 to 11 , wherein in step b) the semi- autonomous vehicle is controlled to move the semi-autonomous vehicle to a storage location to retrieve a load.

13. A storage facility comprising a first zone and a second zone, in which the first zone is reserved for use by one or more autonomous guided vehicles and the second zone is reserved for use by one or more controllers for autonomous guided vehicles according to any of claims 1 to 4 and one or more semi-autonomous vehicles according to any of claims 5 to 8.

14. A storage facility according to claim 13, wherein the storage facility comprises a physical barrier to separate the first zone from the second zone.

15. A storage facility according to claim 14, wherein the physical barrier comprises one or more apertures through which an autonomous guided vehicle or a semi- autonomous vehicle may pass.

16. A storage facility according to claim 15, wherein a handover location may be defined adjacent to one or each of the barrier apertures.

17. A storage facility according to any of claims 13 to 16, wherein the first zone is contiguous with the second zone.

18. A storage facility according to any of claims 13 to 16, wherein the first zone is has an overlap region with the second zone.