Adjustable Spacers

Abstract

An adjustable spacer (80) for adjusting a spacing between two objects, comprising: i) a first rotatable indexing mechanism (82), the first rotatable indexing mechanism (82) configured to rotate in a first rotational direction about an axis of rotation; and ii) a second rotatable indexing mechanism (84), the second rotatable indexing mechanism (84) configured to rotate in a second rotational direction about an axis of rotation, the second rotational direction being opposite to the first rotational direction, wherein the first and second rotatable indexing mechanisms The indexing mechanisms (82, 84) are configured to change the length of the adjustable spacer (80) along the axis of rotation by a first length when the first rotatable indexing mechanism (82) rotates a given angular rotation in a first rotational direction about the axis of rotation, and to change the length of the adjustable spacer (80) along the axis of rotation by a second length when the second rotatable indexing mechanism (84) rotates the same given angular rotation in a second direction about the axis of rotation, the second length being the same or different from the first length of the adjustable spacer (80).

Description

[Technical field]

[0001] The present invention relates to the field of adjustable spacers for varying the spacing between two objects, and more specifically in the application of a grid framework structure to support remotely operated material handling equipment for handling storage containers or receptacles stacked within the grid framework structure. [Background technology]

[0002] Storage systems 1 are known that comprise a three-dimensional storage grid framework structure within which storage containers / receptacles are stacked on top of each other. PCT Publication No. WO2015 / 185628A (Ocado) describes a known storage and fulfilment or distribution system in which a stack of receptacles or containers are arranged within the grid framework structure. The receptacles or containers are accessed by remotely operated material handling equipment on a truck located on top of the grid framework structure. A system of this type is illustrated diagrammatically in Figures 1 to 3 of the accompanying drawings.

[0003] As shown in Figures 1 and 2, stackable containers known as storage receptacles or containers 10 are stacked on top of each other to form a stack 12. The stack 12 is arranged within a three-dimensional grid framework structure 14 in a warehouse or manufacturing environment. The grid framework is made up of a number of storage or grid columns. Each grid of the grid framework structure has at least one grid column for storing a stack of containers. Figure 1 is a schematic perspective view of the grid framework structure 14, and Figure 2 is a top view showing the stack 12 of receptacles 10 arranged within the framework structure 14. Each receptacle 10 typically holds multiple product items (not shown), which may be the same or may be of different product types depending on the application.

[0004] In particular, the three-dimensional grid framework structure 14 comprises a plurality of vertical uprights or upright members or upright columns 16 that support horizontal grid members 18, 20. A first set of parallel horizontal grid members 18 are positioned at right angles to a second set of parallel horizontal grid members 20 to form a grid structure or grid 15 comprising a plurality of grid cells 17. The grid cells have openings that allow loading and unloading equipment to lift containers or storage receptacles through the grid cells. In the grid structure, the first set of parallel horizontal grid members 18 intersect with the second set of parallel horizontal grid members at nodes. The grid structure is supported by upright members 16 at each of the nodes or at the points where the grid members intersect, whereby the upright members are interconnected at their upper ends by the intersecting grid members. The grid members 16, 18, 20 are typically fabricated from metal and are typically welded or bolted together, or a combination of both. The storage receptacles or containers 10 are stacked between upright members 16 of a grid framework structure 14 such that the uprights 16 prevent horizontal movement of the stack 12 of receptacles 10 and guide vertical movement of the storage receptacles 10 .

[0005] The top level of the grid framework structure 14 includes rails 22 arranged in a grid pattern across the top of the stacks 12. With further reference to FIG. 3, the rails 22 support a plurality of load handling devices 30. A first set 22a of parallel rails 22 guides movement of the robotic load handling device 30 in a first direction (e.g., X direction) across the top of the grid framework structure 14, and a second set 22b of parallel rails 22 arranged at right angles to the first set 22a guides movement of the load handling device 30 in a second direction (e.g., Y direction) that is at right angles to the first direction. In this manner, the rails 22 enable lateral movement of the robotic load handling device 30 in two dimensions in the horizontal XY plane, such that the load handling device 30 can be moved to a position above any of the stacks 12.

[0006] A known load handling apparatus, otherwise known as a bot 30, shown in Figures 4 and 5 and described in PCT Patent Publication No. WO2015 / 019055 (Ocado), incorporated herein by reference, comprises a vehicle body 32, each of which covers only a single grid space or grid cell of a grid framework structure 14. Here, the load handling apparatus 30 comprises a wheel assembly comprising a first set of wheels 34, consisting of a pair of wheels at the front of the vehicle body 32 and a pair of wheels 34 at the rear of the vehicle 32, for engaging a first set of rails or tracks that guide the movement of the apparatus in a first direction, and a second set of wheels 36, consisting of a pair of wheels 36 on each side of the vehicle 32, for engaging a second set of rails or tracks that guide the movement of the apparatus in a second direction. Each set of wheels is driven to enable the vehicle to move along the rails in the X and Y directions, respectively. One or both sets of wheels can be moved vertically to lift each set of wheels off their respective rails, thereby allowing the vehicle to move in a desired direction on the grid structure, e.g., in the X or Y direction.

[0007] The loading device 30 is equipped with a lifting device or crane mechanism for lifting the storage container from above. The crane mechanism comprises a winch tether or cable 38 wound on a spool or reel (not shown) and a grabber device 39 in the form of a lifting frame. The lifting device comprises a set of vertically extending lifting tethers 38 connected near or to the four corners of the lifting frame 39, otherwise known as grabber devices, for releasably connecting to the storage container 10 (one tether near each of the four corners of the grabber device). The grabber device 39 is configured to releasably grip the top of the storage container 10 and lift it from a stack of containers in a storage system of the type shown in Figures 1 and 2.

[0008] The wheels 34, 36 are arranged around a cavity or recess known as a container receiving recess 41 in the lower portion. The recess is sized to accommodate the container 10 when it is lifted by the crane mechanism as shown in Figures 5(a) and (b). When in the recess, the container is lifted away from the underlying rail so that the vehicle can move laterally to a different location. Upon reaching the target location, for example another stack, an access point in a storage system, or a conveyor belt, the receptacle or container can be lowered from the container receiving portion and released from the grabber device. The container receiving space may comprise a cavity or recess located in the vehicle body, for example as described in WO2015 / 019055 (Ocado Innovation Limited). Alternatively, the vehicle body of the load handling device may comprise a cantilever as taught in WO2019 / 238702 (Autostore Technology AS), in which case the container receiving space is located below the cantilever of the load handling device. In this case, the grabber device is lifted by the cantilever so that it can engage a container and lift it out of the stack and into the container-receiving space below the cantilever.

[0009] To construct a grid framework structure in the art, a plurality of vertical uprights are individually positioned in a grid-like pattern on the ground. Subgroups of the vertical uprights are braced together to provide structural stability to the grid framework structure. The vertical uprights are interconnected at their upper ends by grid members such that the grid members adopt the same grid pattern as the vertical uprights, i.e., the vertical uprights support the grid members at the points where they intersect in the grid pattern. For the purposes of the present description, the points or junctions where the grid members intersect or are interconnected form the nodes of the grid structure and correspond to the areas where the grid structure is supported by the vertical uprights. The resulting grid framework structure can be considered as a free-standing linear assembly of upright columns supporting a grid formed from intersecting horizontal grid members, i.e., a four-wall shaped framework.

[0010] When one or more load handling devices operate on the grid structure, it is of utmost importance that the grid structure is in a substantially horizontal plane, as this affects the direction in which the container or storage receptacle is lifted into position through the grid cells. If the level of the grid structure is misaligned from the horizontal plane, this will not only strain the one or more load handling devices moving on the grid structure, but will also cause the lifting tethers to swing to one side depending on the direction of misalignment, and in a worst case scenario, cause the grabber device to fail to engage the container or storage receptacle below. This problem is exacerbated when the floor on which the grid framework structure is installed is uneven. Conventionally, the level of a grid structure attached to vertical uprights is adjusted by having adjustable leveling feet at the base or bottom end of the vertical uprights to compensate for uneven floors. The level of the grid structure is adjusted by trial adjustment of adjustable leveling feet at the base of one or more vertical uprights in the grid framework structure and checking the level of the grid structure at the top of the grid structure each time an adjustment is made, for example by using a suitable leveling measuring tool such as a laser level as is commonly known in the art. In many cases, this requires the use of a specialist tool to rotate a threaded shaft to allow the height of the adjustable leveling feet to be varied. However, the problem with this approach is that the separation between the adjustable feet and the grid structure, which may exceed the height of 21 containers or storage vessels, makes incremental adjustments of the level of the grid structure at the top level difficult and time-consuming due to this separation. Furthermore, given the weight and variable forces that the grid framework structure is continuously subjected to during its operation, an initially flat grid structure may become uneven over time, necessitating periodic adjustments of the level of the grid structure. This requires the user to identify uneven areas in the grid structure and adjust the base of the grid framework structure, which involves adjusting one or more adjustable leveling feet at the base of one or more vertical uprights, and periodically checking the level of the grid structure at the top.The time and effort required to periodically check the level of the grid structure at the top of the structure and adjust adjustable leveling feet at the base of the grid framework structure is problematic because checking the level of the grid is not actually performed in real time where the adjustments are made.

[0011] US 10,660,438 (Autostore Technology AS) attempts to alleviate this problem by providing a self-adjusting leveling foot with a base having a raised hollow column. A spring is disposed within the hollow column. A movable upper part engages the column and is vertically movable against the force of the spring. The upper part is slightly larger than the column so that when the spring is compressed, the side walls of the upper part overlap the sides of the column. The bottom edges of the side walls of the upper part are angled. A generally U-shaped wedge device is provided which can be pressed into engagement with the base, whereby a leg of the U engages each side of the column. The upper surfaces of the legs of the U-shaped device are angled in the form of a wedge, the angle of the upper surfaces of the legs corresponding to the angle of the side walls of the movable upper part. In this way, the side walls of the upper part will rest against the angled upper surfaces of the legs of the wedge device when the upper part is under load. However, the problem with this grid leveling mechanism is that if the floor sinks, the U-shaped wedge device needs to be pushed further forward to achieve a stable base of support, again requiring the grid level to be measured at the top.

[0012] Therefore, there is a need for an adjustable grid leveling mechanism that allows the level of the grid structure to be easily adjusted.

[0013] This application claims priority to UK Patent Application No. 2118393.4, filed December 17, 2021, the contents of which are incorporated herein by reference. Summary of the Invention

[0014] In addition to having the advantage of adjusting the level of the grid structure, the present invention has a broader application for adjusting the spacing between any two objects. Thus, the present invention provides an adjustable spacer for adjusting the spacing between two objects, the adjustable spacer comprising: i) a first rotatable indexing mechanism configured to rotate in a first rotational direction about an axis of rotation; ii) a second rotatable indexing mechanism configured to rotate in a second rotational direction about an axis of rotation, where the second direction is opposite to the first direction; The first and second rotatable indexing mechanisms are configured to change a length of the adjustable spacer along the axis of rotation by a first length when the first rotatable indexing mechanism rotates a given angular rotation in a first rotational direction about the axis of rotation, and to change a length of the adjustable spacer along the axis of rotation by a second length when the second rotatable indexing mechanism rotates the same given angular rotation in a second rotational direction about the axis of rotation, the second length being the same as or different from the first length.

[0015] Optionally, the first length is shorter than the second length to provide a coarse level of adjustment and a fine level of adjustment of the length of the adjustable spacer. The first and second rotatable indexing mechanisms are mounted coaxially such that their respective rotational axes are coaxial, i.e., both the first and second rotatable indexing mechanisms can both rotate about the same rotational axis. For example, the first and second rotational directions about the rotational axis of the first and second rotatable indexing mechanisms can be clockwise and counterclockwise directions, respectively. Each rotatable indexing mechanism of the first and second rotatable indexing mechanisms is configured to rotate about the rotational axis in one direction, but is prevented from rotating in the opposite rotatable direction. In this manner, the first rotatable indexing mechanism can be configured to rotate the second indexing mechanism, thus providing the advantage of having a single engagement point with the adjustable spacer to rotate both the first and second rotatable indexing mechanisms about their respective first and second rotational directions.

[0016] To allow rotation in both the first and second rotational directions from a single point of engagement with the adjustable spacer, optionally the adjustable spacer comprises: i) a first cam member rotatable about an axis of rotation, the first cam member having a first mating surface; ii) a second cam member rotatable about a rotation axis, the second cam member having a second mating surface; and iii) an intermediate cam member interposed between the first cam member and the second cam member, the intermediate cam member being rotatable about an axis of rotation and having a first intermediate mating surface for engaging the first mating surface to provide a first rotatable indexing mechanism and a second intermediate mating surface for engaging the second mating surface to provide a second rotatable indexing mechanism; The first intermediate mating surface and each mating surface of the first mating surface have a contour or profile with a variable thickness that varies circumferentially or that varies to change a length of the adjustable spacer along the axis of rotation by a first length when the first cam member rotates in a first rotational direction about the axis of rotation relative to the intermediate cam member through a given angular rotation, and the second intermediate mating surface and each mating surface of the second mating surface have a contour or profile with a variable thickness that varies circumferentially or that varies to change a length of the spacer along the axis of rotation by a second length when the intermediate cam member rotates in a second rotational direction opposite the first rotational direction about the axis of rotation relative to the second cam member through the same given angular rotation.

[0017] When the adjustable spacers of the present invention are used to adjust the level of the grid structure, the thickness of the profile or contour is equivalent to the height of the profile or contour of the mating surface.

[0018] Preferably, the contour or profile of each of the first intermediate mating surface and the first mating surface is configured to prevent the intermediate cam member from rotating in the second rotational direction relative to the first cam member or to prevent the first cam member from rotating in the second rotational direction relative to the intermediate cam member, and the contour or profile of each of the second intermediate mating surface and the second mating surface is configured to prevent the intermediate cam member from rotating in the first rotational direction relative to the second cam member.

[0019] For example, the first rotatable indexing mechanism may be a first ratchet mechanism and the second rotatable indexing mechanism may be a second ratchet mechanism, such that the first intermediate mating surface and the first mating surface each include a plurality of teeth to provide the first ratchet mechanism and the second intermediate mating surface and the second mating surface each include a plurality of teeth to provide the second ratchet mechanism. Optionally, each of the plurality of teeth of the first and second indexing mechanisms is wedge shaped.

[0020] By having first and second rotatable indexing mechanisms rotatable about the same axis of rotation through a single engagement point with the adjustable spacer, the adjustable spacer of the present invention can be used to provide a fine level of adjustment of the length of the adjustable spacer in a first rotational direction about the axis of rotation and a coarse level of adjustment of the length of the adjustable spacer in a second rotational direction about the axis of rotation. In other words, opposite rotation of the first and second rotatable indexing mechanisms provides a coarse level of adjustment and a fine level of adjustment of the length of the adjustable spacer, thus allowing for independent coarse and fine adjustments. The teeth allow rotation in one rotational direction about the axis of rotation, but lock in the other rotational direction as the teeth engage. For example, the teeth on the mating surface of the first cam member may run over the teeth of the intermediate cam member in a first rotational direction about the axis of rotation, but engage when attempting to rotate in a second rotational direction.

[0021] The length of the adjustable spacer is preferably adjustable by configuring each of the first intermediate mating surface and the first mating surface to have at least one first ramp, inclined to change the length of the adjustable spacer along the axis of rotation by a first length when the first cam member rotates through a given angular rotation in a first rotation direction relative to the intermediate cam member, and each of the second intermediate mating surface and the second mating surface to have at least one second ramp, inclined to change the length of the adjustable spacer along the axis of rotation by a second length when the intermediate member rotates through a given angular rotation in a second rotation direction relative to the second cam member. The terms "first ramp" and "first type of ramp" are used interchangeably throughout this application. Similarly, the terms "second ramp" and "second type of ramp" are used interchangeably throughout this application.

[0022] To ensure the stability of the adjustable spacer, more specifically the stability of each of the first cam member, the second cam member, and the intermediate cam member when mounted together such that their respective rotational axes are coaxial, at least one of the first and / or second ramps comprises three or more ramps. Three ramps provide a "tripod" effect at the mating surface. However, the invention is not limited to three ramps and may have any number of ramps. Alternatively, the contour or profile of the first and second mating surfaces and the first and second intermediate surfaces is helical to vary the length of the adjustable spacer when any one of the first and second cam members rotates about its rotational axis relative to the intermediate cam member.

[0023] The at least one first ramp is shallower than the at least one second ramp to provide a coarse level of adjustment and a fine level of adjustment of the adjustable spacer for a given angular rotation about the axis of rotation. The angle the ramp makes with the underside of the cam member controls the length adjustment of the adjustable spacer. A steeper sloped ramp provides a coarser adjustment of the length of the adjustable spacer. Conversely, a shallower or more gently sloped ramp provides a finer adjustment of the length of the adjustable spacer. Similarly, if the profile of the mating surface is helical, the steepness of the helical profile controls the separation of the cam members when rotated about the axis of rotation and therefore the length of the adjustable spacer.

[0024] To independently provide both coarse and fine level adjustment, optionally the first and second intermediate mating surfaces cooperate with the first and second mating surfaces, respectively, such that rotation of the first cam member in a second rotational direction about the axis of rotation causes the intermediate cam member to rotate in a second rotational direction relative to the second cam member. Thus, rotation of the first cam member in a first rotational direction about the axis of rotation causes the first cam member to rotate relative to the intermediate cam member, and rotation of the first cam member in the second rotational direction (opposite to the first rotational direction) causes the intermediate cam member to rotate in the second rotational direction relative to the second cam member. This is possible because mating surfaces between the first cam member and the intermediate cam member provide a first ratchet mechanism, mating surfaces between the intermediate cam member and the second cam member provide a second ratchet mechanism, the first ratchet mechanism providing for rotation of the first cam member relative to the intermediate cam member in a first rotational direction but not in a second rotational direction, and the second ratchet mechanism providing for rotation of the intermediate cam member relative to the second cam member in a second rotational direction but not in the first rotational direction. To allow rotation of the first cam member about an axis of rotation in the first rotational direction and rotation of the intermediate cam member about an axis of rotation in the second rotational direction relative to the second cam member, preferably the second cam member is fixed (i.e. prevented from rotating) for rotation of the intermediate cam member in the second rotational direction about the axis of rotation relative to the second cam member.

[0025] To provide rotation of the first and second indexing mechanisms via rotation of the first cam member, optionally the first cam member includes a plurality of teeth extending outwardly or externally of the periphery of the first cam member for engagement with a pinion. The plurality of teeth extending outwardly of the periphery of the first cam member enable rotation of the first cam member about an axis of rotation via engagement with an external adjustment tool. Preferably, the adjustment tool is a pinion that can mesh with the plurality of teeth on the periphery of the first cam member and rotate the first cam member in first and second rotational directions about the axis of rotation to provide both coarse and fine adjustment of the length of the adjustable spacer.

[0026] To enable the first and second cam members and the intermediate cam member to rotate about their respective rotational axes that are substantially coaxial, optionally the first cam member and the intermediate cam member are each ring-shaped. For purposes of the present invention, the term "ring-shaped" is taken to include any shaped plate or body having a hole (typically in the center) that is typically used to distribute loads across the cam members. Preferably, the ring-shaped cam member is an annular plate or body, e.g., a washer.

[0027] To provide an indication of the length of the adjustable spacer each time the first cam member is rotated in either the first or second rotational direction, optionally the first and second cam members and the intermediate cam member each include at least one marker for measuring the position of any one of the first cam member and / or the intermediate cam member and / or the second cam member relative to each other. For example, the angular position of the first cam member relative to the second cam member can provide an indication of the angular rotation of the first cam member relative to the second cam member. Different angular rotations of the first cam member relative to the second cam member can be calibrated to different lengths of the adjustable spacer. The angular position of the first cam member relative to the intermediate cam member can be determined by markers on the first and intermediate cam members. The same principle applies with respect to the angular position of the intermediate cam member relative to the second cam member.

[0028] The present invention provides an adjustable grid leveling mechanism for adjusting the level of a grid structure of a three-dimensional grid framework structure comprising a plurality of vertical uprights supporting the grid structure, by applying the adjustable spacer of the present invention to adjust the level of the grid structure of the grid framework structure. The plurality of vertical uprights may form part of prefabricated panels braced by one or more bracing members extending between the plurality of vertical uprights. The grid framework structure may be formed from a plurality of prefabricated panels arranged in a grid pattern to form a supporting framework structure. The grid structure is supported or attached on the supporting framework structure to form a grid framework structure according to an example of a grid framework structure of the present invention. The grid structure comprises a plurality of grid members arranged in a grid pattern comprising a plurality of grid cells. The adjustable grid leveling mechanism comprises a base for attachment to the top or upper end of the vertical uprights, a mounting head on which the grid structure is mounted, and an extendable section interposed between the base and the mounting head such that the mounting head is movable relative to the base, the extendable section comprising an adjustable spacer of the present invention. Optionally, the base includes a receptacle or insert for attachment to the vertical upright. The receptacle may be integral to the second cam member for attaching the second cam member to the vertical upright. The receptacle secures the second cam member to the vertical upright such that a single point of engagement with the first cam member allows the first cam member to rotate in a first rotational direction relative to the intermediate cam member and the intermediate cam member to rotate in a second rotational direction relative to the second cam member.

[0029] To interpose the adjustable spacer between the grid structure and one or more of the vertical uprights, the mounting head optionally comprises a rail cross member with four right-angled ends, each of the four right-angled ends configured to support a separate grid member in a grid pattern. The rail cross support is configured to connect the grid members extending in the first and second directions to the vertical uprights. More specifically, the vertical uprights are interconnected at their upper ends, i.e., at junctions where the first set of grid members intersects with the second set of grid members in the grid structure, by a first set of grid members extending in the first direction and a second set of grid members extending in the second direction. The rail cross member interconnects the first and second sets of grid members to the vertical uprights at junctions where the first and second sets of grid members intersect in the grid structure. The junctions where the first and second sets of grid members intersect in the grid structure are commonly known as nodes. To attach the adjustable spacer to the vertical uprights, optionally the second cam member includes a spigot for attachment to the vertical uprights at the nodes of the grid structure.

[0030] The present invention further provides a grid framework structure configured to support one or more load handling apparatus, the grid framework structure comprising: i) a grid structure comprising a first set of grid members extending in a first direction and a second set of grid members extending in a second direction, where the second set of grid members extend transversely to the first set of grid members in a substantially horizontal plane and in a grid pattern comprising a plurality of grid cells; ii) a plurality of vertical uprights for supporting a grid structure, the plurality of vertical uprights being interconnected at upper ends thereof by the first set of grid members and the second set of grid members; iii) an adjustable grid leveling mechanism of the present invention interposed between at least one of the plurality of vertical uprights and the grid structure at one or more of the interconnections of the plurality of vertical uprights, wherein the adjustable spacer is configured to adjust the vertical distance between at least one of the plurality of vertical uprights and the grid structure.

[0031] By interposing the adjustable grid leveling mechanism between at least one of the plurality of vertical uprights and the grid structure, the measurement and operation of the adjustable grid leveling mechanism can be performed from the same location. This has the advantage that fewer operators are required to measure and adjust the grid level. As a result, adjustments of the grid level can be made in real time, as opposed to first measuring the grid level and then making the necessary adjustments afterwards, which may not be accurate and would require further adjustments to be made at the bottom of the vertical uprights. Another advantage of mounting the grid structure on the adjustable grid leveling mechanism is that the components of the adjustable grid leveling mechanism do not need to support the full weight of the vertical uprights, since the adjustable grid leveling mechanism has been moved to the top end of the vertical uprights. This provides a grid framework structure with greater flexibility to anchor the bottom end of the vertical uprights on a more rigid bottom portion that provides greater lateral stability than the adjustable grid leveling mechanism alone could provide. Furthermore, threaded axles known in the art for adjusting the height, and therefore the level, of a grid structure may wear over time as they tend to support the full weight of the grid structure and one or more loading devices operating on the grid structure. This results in cross-threading of the axle, eliminating its ability to adjust its height, i.e., to move vertically. This weakness does not exist when the adjustable spacer includes opposing mating faces, because the load is distributed or spread over a larger surface area of ​​the mating faces of the cam members, rather than the threaded axle. For purposes of the present invention, grid level refers to the orientation of the grid structure in a horizontal plane. By adjusting the height in one or more areas of the grid structure, the orientation of the grid structure in the horizontal plane is adjusted.

[0032] Preferably, the plurality of vertical uprights are arranged to form a plurality of vertical storage locations for one or more containers to be stacked between and vertically guided by the vertical uprights. Preferably, the grid structure is attached to an adjustable grid levelling mechanism at one or more of the interconnections of the plurality of vertical uprights.

[0033] The present invention further provides a robotic grid levelling apparatus for moving over a grid structure according to the present invention, the robotic grid levelling apparatus comprising: A) a wheel assembly, i) a first set of wheels for moving the robotic leveling device in a first direction; ii) a second set of wheels for moving the robotic leveling device in a second direction; A) a wheel assembly; B) a drive mechanism for selectively driving the first and / or second sets of wheels; and C) an adjustment tool configured to rotate the first and / or second rotatable indexing mechanisms in their respective first and second rotational directions about the rotation axis.

[0034] Optionally, the adjustment tool comprises a pinion for engaging the first and / or second rotatable indexing mechanisms. Measurement of the vertical position of the robotic grid leveling device at different locations on the grid structure relative to one or more fixed reference points can provide an indication of the level of the grid structure. Multiple measurements of the vertical position of the robotic load handling device at different locations on the grid structure can be used by the control system to determine an orientation or plane in which the grid structure lies and whether adjustment is needed to any one of the adjustable grid leveling mechanisms interposed between the grid structure and the vertical uprights to ensure that the grid structure lies in a substantially horizontal plane.

[0035] In a further aspect of the present invention, there is provided a method of levelling a grid structure of a grid framework structure, the method comprising the steps of: i) measuring a first vertical position of a robotic grid leveling device in a first grid cell of a grid structure relative to one or more fixed reference points; ii) moving the robotic leveling device on the grid structure to a second grid cell on the grid structure; iii) measuring a second vertical position of the robotic leveling device on the grid structure in a second grid cell relative to one or more fixed reference points; iv) calculating a difference between the measured second vertical position and the first vertical position; This means, v) if the calculated difference is greater than the predetermined value, adjusting the length of the adjustable spacer by engaging the adjustable tool with the adjustable spacer to rotate the first and / or second rotatable indexing mechanisms in their respective first and / or second rotational directions about the axis of rotation until the calculated difference is less than the predetermined value; and vi) repeating steps (i) to (iv) until the grid structure is substantially horizontal.

[0036] Optionally, the one or more fixed reference points are located at one or more corners of the grid structure. Ideally, the predetermined values ​​are all fixed and substantially equal to zero, such that the vertical positions of the robotic leveling devices at different grid cells do not change significantly, indicating that the portions of the grid structure covered by the different grid cells are in a substantially horizontal plane. The process of measuring the vertical positions of the robotic leveling devices at different grid cells covering different portions of the grid structure is repeated, and adjustments are made, if necessary, to their respective adjustable grid leveling mechanisms so that the difference in vertical positions is within a predetermined value. Optionally, the level of the grid structure is set to a predetermined reference level, and the vertical position of the robotic grid leveling devices is adjusted relative to the predetermined reference level.

[0037] The vertical position of the robotic leveling device can be determined by measuring the angle of the robotic leveling device from one or more of the fixed reference points and knowing the distance between the fixed reference points, and the measured angle can be used to determine the vertical position of the robotic leveling device relative to the fixed reference points and therefore the vertical position on the grid structure. One example of measuring the vertical position of the robotic leveling device relative to the multiple fixed reference points is by using one or more total stations by a process of triangulation. Preferably, the first and second vertical positions of the robotic leveling device are measured by one or more total stations at one or more of the fixed reference points, each of the one or more total stations comprising a transmitter device at one or more of the multiple fixed reference points for illuminating the robotic leveling device with light of at least one wavelength and a receiver device at one or more of the multiple fixed reference points for receiving light reflected from the robotic leveling device. One or more mirrors can be attached to the robotic leveling device to reflect the light sent from the fixed reference points to the robotic leveling device. The reverse is also applicable where the robotic leveling device transmits light of at least one wavelength to one or more of the fixed reference points and there is a receiver for receiving the light reflected from the one or more fixed reference points, the fixed reference points comprising one or more mirrors for reflecting the light transmitted from the transmitter.

[0038] The present invention further provides a grid leveling system, the grid leveling system comprising: i) a grid framework structure of the present invention; ii) a robotic leveling device that operates on the grid structure of the grid framework structure; and iii) a control system comprising one or more processors and a memory storing instructions that, when executed by the one or more processors, cause the one or more processors to: a) measuring a first vertical position of a robotic leveling device on a grid structure in a first grid cell on the grid structure relative to a plurality of fixed reference points on the grid structure; b) moving the robotic leveling device to a second grid cell on the grid structure; and c) measuring a second vertical position of the robotic leveling device in a second grid cell on the grid structure relative to a plurality of fixed reference points on the grid structure; d) calculating a difference between the second vertical position and the first vertical position; If the calculated difference is greater than a predetermined value, then a length of the adjustable spacer is adjusted by engaging an adjustable tool with the adjustable spacer to rotate the first and / or second rotatable indexing mechanisms in their respective first and second rotational directions about the rotation axis until the calculated difference is less than the predetermined value.

[0039] Additional features and aspects of the present invention will become apparent from the following detailed description of illustrative embodiments which proceeds with reference to the drawings. [Brief description of the drawings]

[0040] [Figure 1] FIG. 1 is a schematic diagram of a grid framework structure according to a known system. [Diagram 2] FIG. 2 is a schematic diagram of a top view showing a stack of containers arranged within the framework structure of FIG. [Diagram 3] FIG. 3 is a schematic diagram of a known storage system for load handling equipment operating on a grid framework structure. [Figure 4] FIG. 4 is a schematic perspective view of the loading equipment showing a lifting device for gripping a container from above. [Diagram 5] 5(a) and 5(b) are schematic perspective cutaway views of the loading equipment of FIG. 4, showing (a) a container accommodated in a container receiving space of the loading equipment, and (b) the container receiving space of the loading equipment. [Figure 6]FIG. 6 is a perspective view showing an arrangement of tracks and track supports interconnected at their nodes or intersections by cap plates. [Figure 7] FIG. 7 is a perspective view of the track support. [Figure 8] FIG. 8 is a perspective view of a cap plate for interconnecting the vertical uprights to the grid members at the nodes. [Figure 9] FIG. 9 is a perspective cross-sectional view of the interconnection of the vertical uprights and grid members by cap plates at the nodes. [Figure 10] FIG. 10 is a perspective view of a track or rail. [Figure 11] FIG. 11 is a perspective view showing four vertical uprights that make up a storage space or column within a grid framework structure. [Figure 12] FIG. 12 is a perspective view of a known adjustable grid leveling mechanism at the bottom of a vertical upright. [Figure 13] FIG. 13 is a perspective view of the known adjustable grid leveling mechanism shown in FIG. [Figure 14] FIG. 14 is a perspective view of an adjustable spacer in accordance with one embodiment of the present invention. [Figure 15] FIG. 15 is an exploded view of the adjustable spacer shown in FIG. [Figure 16] 16(a) and 16(b) are perspective views illustrating the different adjustments of the length of the adjustable spacer provided by (a) the second indexing mechanism and (b) the first indexing mechanism. [Figure 16c] FIG. 16c is a perspective view of an alternative embodiment of the different adjustments of the lengths of the adjustable spacers provided by the first and second indexing mechanisms shown in FIGS. 16(a) and (b). [Figure 17] FIG. 17 is a perspective view of an adjustable grid leveling mechanism interposed between a portion of a grid structure and a vertical upright in accordance with a first embodiment of the present invention. [Figure 18]FIG. 18 is a perspective view of an adjustable grid leveling mechanism with adjustable spacers of FIGS. 14-16(a) and (b) of the present invention. [Figure 19] FIG. 19 is an exploded view of the adjustable grid leveling mechanism shown in FIG. 18 with a mounting head for supporting the grid structure. [Figure 20] FIG. 20 is a perspective view of a section of a grid framework structure showing the attachment of the grid structure to the vertical uprights by an adjustable grid leveling mechanism. [Figure 21] FIG. 21 is a perspective view of the engagement between the pinion and the adjustable spacer. [Figure 22] FIG. 22 is a perspective view of the engagement of the pinion and adjustable spacer through a grid structure. [Diagram 23] FIG. 23 is a perspective view of a robotic grid leveling device operable on a grid structure. [Figure 24] FIG. 24 is a perspective view of a robotic grid leveling device operable on a grid structure interacting with a total station at one or more fixed reference points to measure the vertical position of the robotic leveling device on the grid structure. [Diagram 25] FIG. 25 is a flow chart of an exemplary process for leveling a grid structure by a robotic grid leveling device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The present invention is devised in contrast to known features of storage systems such as grid framework structures and load handling equipment described above with reference to Figures 1 to 5. As shown in Figure 6, a grid structure 40 for guiding the movement of one or more load handling equipment comprises a first set of parallel grid members extending in a first direction and a second set of parallel grid members extending in a second direction, the first direction being substantially perpendicular to the second direction so as to form a rectangular or square frame of a plurality of grid cells. More specifically, the first set of grid members extends in a first direction and the second set of grid members extends in a second direction, the second set of grid members extending transversely to the first set of grid members in a substantially horizontal plane, i.e. the grid structure is represented by Cartesian coordinates in the X and Y directions. Each of the grid members may include a track support 18, 20 and / or a track or rail 22a, 22b, whereby the track or rail 22a, 22b is attached to the track support 18, 20. A loading device is operative to move along the track or rail 22a, 22b of the present invention. Alternatively, the track 22a, 22b may be integral to the track support 18, 20 as a unit, for example by extrusion. In a particular embodiment of the present invention, the grid members include a track support 18, 20 and a track 22a, 22b, whereby the track or rail 22a, 22b is attached to the track support 18, 20.

[0042] Typically, at least one grid member in the set, e.g., a single grid member, may be subdivided or sectioned into individual grid elements that may be joined or linked together to form a grid member extending in a first direction or a second direction. When the grid member comprises track supports 18, 20, the track supports may also be subdivided into individual track support elements that are linked together to form the track supports. The individual track support elements that make up the track supports extending in the first and second axial directions are shown in FIG. 6. The individual track support elements 56 used to make up the track supports 18, 20 are shown in FIG. 7. The track supports 18, 20 may be solid supports of C-shaped, U-shaped or I-shaped cross section in transverse cross section, or even double C-shaped or double U-shaped supports. In a particular embodiment of the invention, the track support elements 56 comprise double back-to-back C-sections bolted together.

[0043] The connecting or cap plates 58 shown in Figures 6 and 8 may be used to tie or join together the individual track support elements 56 in both the first and second directions at the junctions where the track support elements meet within the grid structure 40, i.e. the cap plates 58 are used to connect these track support elements 56 together to the vertical uprights 16. As a result, the vertical uprights 16 are interconnected at their upper ends by the cap plates 58 at the junctions where the track support elements meet within the grid structure 40, i.e. the cap plates are located at the nodes 50 of the grid structure 40. For purposes of the present description, the points or areas where the grid members intersect or cross, as shown in Figure 6, may be defined as nodes or intersections 50. It is clearly apparent from the layout of at least a portion or section of the known grid structure 40 forming a single grid cell 42 shown in Figure 6 that each intersection or node 50 of the grid structure 40 is supported by a vertical upright 16.

[0044] As shown in FIG. 8, the cap plate 58 is cross-shaped with four connecting portions 60 for connecting to the ends of the track support elements 56 at the intersections 50 of the track support elements 56 or anywhere along their length. The interconnection of the track support elements and the vertical uprights at the nodes by the cap plate 58 is shown in the cross-sectional profile of the node 50 shown in FIG. 9. The cap plate 58 includes a spigot or protrusion 62 sized to sit with an interference fit within the hollow section 46 of the vertical upright 16 to interconnect multiple upright columns to the track support elements as shown in FIG. 9. Also shown in FIG. 9 are the track support elements 56a, 56b extending in both orthogonal directions corresponding to a first direction (x-direction) and a second direction (y-direction). The connecting portions 60 are at right angles to each other for connecting to the track support elements 56a, 56b extending in the first and second directions. The cap plate 58 is configured to be bolted to the ends of the track support elements 56a, 56b or along the length of the track support elements. The track support elements 56a, 56b are arranged to interlock with one another at the nodes to form the grid structure 40 in accordance with the present invention. To accomplish this, a distal or opposing end of each of the track support elements 56a, 56b includes a locking feature 64 for interconnecting with a corresponding locking feature 66 of an adjacent track support element. In a particular embodiment of the present invention, the opposing or distal end of one or more of the track support elements includes at least one hook or tongue 64 that is receivable within an opening or slot 66 in the middle of the adjacent track support element 56 at the junction where the track support elements meet in the grid structure 40. Referring back to FIG. 7 in conjunction with FIG. 9, the hook 64 at the end of the track support element 56 is shown to be received in an opening 66 of the adjacent track support element that extends across the vertical uprights 16 at the junction where the track support elements 56 meet. Here, the hooks 64 extend into openings 66 on either side of the track support element 56b.In a particular embodiment of the invention, the opening 66 is midway along the length of the track support element 56 such that when assembled together, adjacent parallel track support elements 56 in the first and second directions are offset by at least one grid cell. This is shown in FIG.

[0045] To complete the grid structure 40, the tracks 22a, 22b are attached to the track support elements 56 once the track support elements 56 are interlocked together to form a grid pattern with the track supports 18 extending in a first direction and the track supports 20 extending in a second direction. The tracks 22a, 22b are either fitted and / or snap-fit ​​onto the track supports 18, 20 in a slip-fit ​​arrangement (see FIG. 6). As with the track supports of the present invention, the tracks comprise a first set of tracks 22a extending in a first direction and a second set of tracks 22b extending in a second direction, the first direction being perpendicular to the second direction. The first set of tracks 22a are subdivided into a plurality of track elements 68 in the first direction such that adjacent parallel track elements in the first direction are offset by at least one grid cell when assembled. Similarly, the second set of tracks 22b are subdivided into a plurality of track elements 68 in the second direction such that, when assembled, adjacent track elements in the second direction are offset by at least one grid cell. This is shown in FIG. 6. An example of a single track element 68 is shown in FIG. 10. As with the track support elements, a plurality of track elements in the first and second directions are laid together to form a track in both directions. The fitting of the track element 68 into the track support 18, 20 comprises an inverted U-shaped cross-sectional profile shaped to embrace or overlap the top of the track support 18, 20. One or more protrusions extending from each branch of the U-shaped profile engage the ends of the track support 18, 20 in a snap-fit ​​arrangement. It is equally valid in the present invention that the tracks 22a, 22b can be integrated into the track support 18, 20 rather than being separate components.

[0046] As shown in FIG. 11, the vertical uprights are typically arranged such that a single grid cell 42 is supported by four vertical uprights 16 to form a single storage column 44 for storing one or more containers 10 in a stack. The horizontal cross-section of the storage location 44 in FIG. 2 shows that each storage column 44 is made up of four vertical uprights 16 arranged at the corners of the container or storage vessel 10. The storage column 44 corresponds to a single grid cell. The cross-section of the vertical uprights 16 is constant over the entire length of the vertical upright. The perimeter of the container or storage vessel in the horizontal plane in FIG. 2 shows the container or storage vessel having four corners and the arrangement of the four vertical uprights 16 at those corners of the container or storage vessel within the storage column 44. The corner sections of each of the four vertical uprights, one from each of the four vertical uprights, ensure that a container or storage receptacle stored in a storage column 44 is guided into the correct position relative to any containers or storage receptacles stored in that storage column and stacks of containers or storage receptacles in the surrounding storage columns. A handling device (not shown) operating on the grid structure 40 can lift the container or storage receptacle as it is guided along the vertical uprights 16 through the grid cells 42.

[0047] The terms "vertical upright(s)", "upright member(s)", and "upright column(s)" are used interchangeably in this description to mean the same thing. Each of the vertical uprights 16 is generally tubular. In particular, as shown in FIG. 2, each of the vertical uprights 16 comprises a hollow section 46 (typically a box-shaped section) having one or more guides 48 attached or formed at the corners of the hollow section 46 extending along the longitudinal length of the vertical upright 16 for guiding the movement of containers along the storage column 44. The one or more guides 48 comprise two right-angled container guide plates. The two right-angled container guide plates are positioned to accommodate a corner of a container or a corner of a stack of containers. In other words, each of the corners of the hollow section 46 defines two sides of a substantially triangular area that may accommodate a corner of a container or a storage vessel. These corners are evenly spaced around the hollow section 46 so that multiple vertical uprights 16 can provide multiple adjacent storage columns, and each vertical upright 16 can be common or shared with up to four separate storage columns.

[0048] 11 and 12 also show that each of the vertical uprights 16 is attached to an adjustable grid leveling mechanism 70 at the bottom of the vertical upright, which comprises a base and a threaded shaft that can be extended or retracted to compensate for an uneven floor. Further details of the adjustable grid leveling mechanism are described below. It should be noted that the present invention is not limited to a grid structure being supported at each of the intersections or nodes of the grid structure. The grid structure may be supported at any section or portion of the grid structure. For example, the grid structure may be supported only at the corners of the grid structure. In this case, the connecting plate or cap plate 58 comprises at least two right angle connecting portions 60 for connecting to the ends of the track support elements or anywhere along their length, at the intersections 50 of the track support elements, for example at the corners of the grid structure.

[0049] As shown in FIG. 11 and shown in detail in FIGS. 12 and 13, the vertical uprights are anchored to the floor, more specifically to a concrete foundation, by adjustable feet 70 with threaded shafts 72 that can be extended or retracted to compensate for uneven floors. As the name suggests, the adjustable feet or adjustable anchor feet 70 are attached to the lower end of the vertical uprights 16. The adjustable feet 70 shown in FIG. 13 include a base plate 74 and a threaded spindle or threaded rod 72 that is threadably engageable with a separate push-fit cap or plug 76. The push-fit cap 76 is arranged to fit with a tight fit on the lower end of the vertical uprights 16 to adjust the height of the vertical uprights 16. The push-fit cap 76 shown in FIGS. 12 and 13 includes a bent portion arranged to receive the lower end of the vertical uprights 16, more specifically, around a box section. In use, the threaded spindle 72 threadably engages with a threaded hole 78 in the push-fit cap 76. Rotating the threaded spindle 72 changes the distance between the base plate 74 resting on the floor and the push-fit cap 76, thereby changing the height of the vertical uprights 16 in the grid framework structure. Traditionally, the grid level has been measured at the top of the vertical uprights each time an adjustment of the adjustable feet 70 at the bottom of the vertical uprights is made. As a result, two operators are needed to correct the level of the grid structure, one at the top of the grid framework structure to measure the level of the grid structure 40, and one at the bottom of the grid framework structure to make the necessary adjustments to the height of the vertical uprights.

[0050] [Adjustable spacer] FIG. 14 is a perspective view of an adjustable spacer 80 according to an embodiment of the present invention. In a preferred embodiment of the present invention, the adjustable spacer 80 according to an exemplary embodiment of the present invention is interposed between the top of a vertical upright and a grid structure to allow adjustment of the grid level at the point where a measurement of the grid level is being performed, but the adjustable spacer has a wider range of practical applications that require adjustment of the separation between two objects. In a preferred embodiment of the present invention shown in FIG. 14, the adjustable spacer 80 comprises a first rotatable indexing mechanism 82 and a second rotatable indexing mechanism 84. The first and second rotatable indexing mechanisms are rotatable about first and second rotatable axes, respectively, that are substantially coaxial, i.e., rotatable about the same rotation axis XX. Each of the first and second rotatable indexing mechanisms 82, 84 is configured to be rotatable about the rotation axis XX relative to each other in one rotation direction but not in the opposite rotation direction. In a particular embodiment of the invention, adjustable spacer 80 comprises an assembly of substantially coaxial cam members rotatable about an axis, namely, a first cam member 86, a second cam member 88, and an intermediate cam member 90 interposed between first cam member 86 and second cam member 88.

[0051] The first, second and intermediate cam members 86, 88, 90 are coaxially mounted such that the first, second and intermediate cam members each have opposing engageable mating surfaces. When the intermediate cam member 90 is interposed between the first cam member 86 and the second cam member 88, the mating surface of the first cam member 86 opposing one mating surface of the intermediate cam member 90 is engageable with the mating surface of the first cam member 86 opposing the mating surface of the second cam member 88 opposing the other mating surface of the intermediate cam member 90. For ease of explanation, the mating surface of the first cam member 86 is referred to as a first mating surface 92, the mating surface of the second cam member 88 is referred to as a second mating surface 94, and the opposing mating surfaces of the intermediate cam member 90 are referred to as a first intermediate mating surface 96 and a second intermediate mating surface 98, respectively. Compared to a threaded shaft, which bears the weight of the grid structure on the threads of the shaft and is therefore prone to cross-threading, as found in prior art grid level adjustment mechanisms, the mating surfaces 92, 94, 96, 98 of the first cam member 86, the second cam member 88, and the intermediate cam member 90 provide the advantage of distributing the load across the mating surfaces, such that the adjustable spacer can withstand heavier loads than a threaded shaft. The first, second, and intermediate cam members 86, 88, 90 are annular or ring-shaped such that the mating surfaces 92, 94 of the first and second cam members 86, 88 are mounted on a carrier or seat with a shaft (not shown) for engagement with the respective opposing mating surfaces 96, 98 of the intermediate cam member 90, allowing rotation about a substantially coaxial axis of rotation XX. One or more slip rings of low friction material may be interposed between the carrier and the outer surface of the adjustable spacer to allow the cam members of the adjustable spacer to rotate relative to the carrier.

[0052] The first, second and intermediate cam members 86, 88, 90 are seated or assembled on one another such that their respective mating or opposing surfaces cooperate. The mating surfaces 92, 94, 96, 98 of the first, second and intermediate cam members are clearly shown in an exploded view of the adjustable spacer in FIG. 15, where the first mating surface 92 of the first cam member 86 is positioned to engage with the first intermediate mating surface 96 of the intermediate cam member 90 to provide the first indexing mechanism 82, and the second mating surface 94 of the second cam member 88 is positioned to engage with the second intermediate mating surface 98 of the intermediate cam member 90 to provide the second indexing mechanism 84. During rotation of the first cam member 86 about the rotation axis XX, the first mating surface 92 moves over the first intermediate mating surface 96 of the intermediate cam member 90, and during rotation of the intermediate cam member 90 about the rotation axis XX, the second intermediate mating surface 98 moves over the second mating surface 94 of the second cam member 88. The first and second indexing mechanisms 82, 84 are configured to allow the first cam member 86 to rotate in one rotation direction (first rotation direction) about the rotation axis XX relative to the intermediate cam member 90, but not in the reverse rotation. The intermediate cam member 90 is capable of rotating in one rotation direction (second rotation direction) about the rotation axis XX relative to the second cam member 88, but not in the reverse rotation (first rotation direction).

[0053] In a particular embodiment of the invention, the first mating surface 92 and the first intermediate mating surface 96 of the first and intermediate cam members 86, 90 each include a plurality of teeth 99 to provide the first indexing mechanism 82. The second mating surface 94 and the second intermediate mating surface 98 of the second and intermediate cam members 88, 90 each include a plurality of teeth 100 to provide the second indexing mechanism 84. The plurality of teeth 99 of the first mating surface 92 and the first intermediate mating surface 96 are wedge-shaped and oriented to allow the first cam member 86 to rotate in a first rotational direction about the rotation axis XX relative to the intermediate cam member 90, but not in a second rotational direction. Similarly, the plurality of teeth 100 of the second mating surface 94 and the second intermediate mating surface 98 are wedge-shaped and oriented to allow the intermediate cam member 90 to rotate in a second rotational direction about the rotation axis XX relative to the second cam member 88, but not in the first rotational direction. The ability of the mating surfaces to be configured to allow rotation in one direction but not the opposite direction allows rotation of the first and second indexing mechanisms 82, 84 from a single point of engagement with the adjustable spacer 80. For example, rotating the first cam member 86 in a first rotational direction about its axis of rotation causes the first cam member 86 to rotate relative to the intermediate cam member 90. However, the first cam member cannot rotate in a second rotational direction about its axis of rotation relative to the intermediate cam member due to the engagement of the plurality of teeth 99 of the first mating surface 92 with the plurality of teeth of the first intermediate mating surface 96, so that rotating the first cam member 86 in the second rotational direction about its axis of rotation forces the intermediate cam member 90 to rotate in the second rotational direction about its axis of rotation relative to the second cam member 88. As a result, both the first and second rotational directions of the first and second cam members 86, 88 relative to the intermediate cam member 90 can be achieved by rotating the first cam member 86 in opposite rotational directions. This may be, for example, clockwise and counterclockwise.

[0054] In a particular embodiment of the present invention, the single engagement point of the adjustable spacer is provided by a plurality of teeth 112 disposed on the outer periphery or periphery of the first cam member for engaging with the pinion (see FIG. 18). In other words, the first cam member 86 is formed as a gear that can mesh with the gear of the pinion. By engaging the pinion with the gear of the first cam member 86, the pinion can rotate the first cam member 86 in both opposite first and second rotational directions about the axis of rotation. However, other means of rotating the first cam member are applicable to the present invention. These include, but are not limited to, various adjustment tools that can engage the first cam member and rotate it relative to the intermediate cam member and / or the second cam member. For example, an edge or side of the first cam member can be provided with one or more openings sized to receive one or more pins for manually rotating the first cam member relative to the intermediate cam member and / or the second cam member.

[0055] The mating or opposing surfaces of the first, second and intermediate cam members 86, 88, 90 have profiles or contours with variable lengths in the circumferential direction of their respective first, second and intermediate cam members 86, 88, 90 such that rotating the first cam member 86 a given angular rotation in a second rotational direction about the rotation axis XX rotates the intermediate cam member 90 relative to the second cam member 88, thereby adjusting the length of the adjustable spacer by a second predetermined length L2 (see FIG. 16a). Conversely, rotating the first cam member 86 a given angular rotation in a first rotational direction opposite to the second rotational direction about the rotation axis XX rotates the first cam member 86 relative to the intermediate cam member 90, thereby adjusting the length of the adjustable spacer by a first predetermined length L1 (see FIG. 16b). Also pertinent to the present invention, the teeth between the mating surfaces may be oriented such that rotating the first cam member 86 in a first rotational direction about the axis of rotation XX rotates the intermediate cam member 90 relative to the second cam member 88, and rotating the first cam member 86 in a second rotational direction about the axis of rotation rotates the first cam member 86 relative to the intermediate cam member 90. The contour or profile of the first mating surface 92 and the first intermediate mating surface 96 may be contoured to provide a different level of adjustment of the length of the adjustable spacer 80 for a given angular rotation than the contour or profile of the second mating surface 94 and the second intermediate mating surface 98. This has the advantage of providing a coarse level of adjustment of the length of the adjustable spacer by rotating the first cam member 86 in one rotational direction and a fine level of adjustment of the length of the adjustable spacer by rotating the first cam member 86 in the other opposite rotational direction.

[0056] In a particular embodiment of the invention shown in Figures 14 and 15, the mating surfaces 92, 94, 96, 98 of the first, second, and intermediate cam members 86, 88, 90 include one or more ramps 101 such that as the first, second, and intermediate cam members rotate relative to one another, the first, second, and intermediate cam members move over the one or more ramps 101 to increase the length of the adjustable spacer. The angle of inclination of the ramps relative to a horizontal or vertical object, depending on whether the adjustable spacer is mounted horizontally or vertically, controls the degree of adjustment of the length of the adjustable spacer for a given angular rotation of the first cam member 86 or second cam member 88 relative to the intermediate cam member 90. For a given angular rotation of the first cam member 86 or second cam member 88 relative to the intermediate cam member 90, a steeper angle of inclination provides a coarser level of adjustment of the length of the adjustable spacer 80 and a gentler angle provides a finer level of adjustment of the length of the adjustable spacer 80. 16(a) and (b), the one or more ramps 102 on the first mating surface 92 of the first cam member 86 and the first intermediate mating surface 96 of the intermediate cam member 90 are shallower than the one or more ramps 101 on the second mating surface 94 of the second cam member 88 and the second intermediate mating surface 98 of the intermediate cam member 90, such that rotating the first cam member 86 in a first rotational direction about the axis of rotation provides fine adjustment of the length of the adjustable spacer (see FIG. 16b), and rotating the first cam member 86 in a reverse second rotational direction about the axis of rotation to rotate the intermediate cam member 90 in the second rotational direction relative to the second cam member 88 provides coarse adjustment of the length of the adjustable spacer. Each incremental rotation of the first cam member 86 relative to the intermediate cam member 90 locks the first cam member 86 against rotation in the reverse rotational direction by the first indexing mechanism 82. Similarly, each incremental rotation of the intermediate cam member 90 relative to the second cam member 88 locks the intermediate cam member 90 against rotation in the reverse rotational direction by the second indexing mechanism 84.

[0057] 16a and 16b show that coarse adjustment is provided between opposing mating surfaces 94, 98 of second cam member 88 and intermediate cam member 90 and fine adjustment is provided between opposing mating surfaces 92, 96 of first cam member 86 and intermediate cam member 90, although vice versa is equally applicable. In an alternative embodiment of adjustable spacer 80b shown in FIG. 16c, first mating surface 92b of first cam member 86b and first intermediate mating surface 96b of intermediate cam member 90b are contoured to provide coarse adjustment of the length of adjustable spacer 80b. Similarly, the second mating surface 94b of the second cam member 88b and the second intermediate mating surface 98b of the intermediate cam member 90b are contoured to provide fine adjustment of the length of the adjustable spacer 80b, i.e., the one or more ramps 102b of the opposing mating surfaces 92b, 96b of the first cam member 86b and the intermediate cam member 90b are steeper than the one or more ramps 101b of the opposing mating surfaces 94b, 98b of the second cam member 88b and the intermediate cam member 90b. Thus, rotating the first cam member 86b relative to the intermediate cam member 90b in a first rotational direction about the rotational axis XX provides a coarse level of adjustment of the length of the adjustable spacer 80b, and rotating the intermediate cam member 90b relative to the second cam member in a second rotational direction about the rotational axis XX provides a fine level of adjustment of the length of the adjustable spacer 80b.

[0058] To improve the stability of the first, second and intermediate cam members when assembled together, the mating faces of the first, second and intermediate cam members include at least three ramps. The at least three ramps on the mating faces of the first, second and intermediate cam members provide a "tripod" effect, thus maintaining the orientation of the first, second and intermediate cam members as they rotate relative to one another about the axis of rotation. Alternatively, the profile or contour of the opposing mating faces of the first, second and intermediate cam members may be helical or spiral such that relative rotation of the first, second and intermediate cam members 86, 88, 90 relative to one another changes the length of the adjustable spacer 80.

[0059] While the particular embodiment shown in Figures 14 and 15 describes two indexing mechanisms 82, 84 provided by the mating surfaces of the first, second, and intermediate cam members 86, 88, 90, the adjustable spacer 80 of the present invention is not limited to two indexing mechanisms, but may include multiple indexing mechanisms, each of which provides a different degree of adjustment of the length of the adjustable spacer for a given rotation of the separate rotatable indexing mechanism. Equally pertinent to the present invention, the two indexing mechanisms provided by the mating surfaces of the first, second, and intermediate cam members may provide the same level of adjustment of the length of the adjustable spacer for a given rotation of the first cam member relative to the intermediate cam member and the intermediate cam member relative to the second cam member. This allows for further adjustment of the length of the adjustable spacer 80 when the first indexing mechanism 82 reaches its maximum adjustment. Furthermore, the adjustment of the length of the adjustable spacer is not limited to only a single engagement point where one cam member provides rotation of both the first and second cam members relative to the intermediate cam member. Adjustment may include rotating other cam members in the cam member assembly to allow rotation of each of the cam members relative to one another.

[0060] [Grid leveling adjustment mechanism] In a preferred application of the present invention, the adjustable spacers may be used to make adjustments to the level of the grid structure 140 as described above. In this case, adjustments to the length of the adjustable spacers refer to adjustments made to the height H of the adjustable spacers. In a preferred embodiment of the present invention, an adjustable grid leveling mechanism comprising the adjustable spacers as described above is interposed between the top of the vertical uprights and the grid structure. This allows adjustments to the grid level to be made at the point where the grid level measurement is being performed. Thus, the grid level adjustments can be made in situ or in real time as the grid level is being measured. An example of moving the adjustable grid leveling mechanism to its connection with the grid structure 140 at the top end of the vertical uprights is shown in FIG. 17. In the particular embodiment of the present invention shown in FIG. 17, the grid members comprise track supports 118, 120 that are connected together at the nodes or intersections 50 of the grid structure 140 by the adjustable grid leveling mechanism 104, rather than being directly connected to the vertical uprights via a cap plate as described above with reference to FIG. 8. Also shown in FIG. 17 are tracks 122a, 122b attached to track supports 118, 120.

[0061] The individual adjustable grid leveling mechanism 104 shown in Figures 18 and 19 comprises a base 106 for mounting to an upper end of a vertical upright 116, a mounting head 108 for mounting to a grid structure 140, and an extendable section 110 comprising an adjustable spacer 80 of the present invention interposed between the base 106 and the mounting head 108 such that the mounting head 108 is vertically movable relative to the base 106. The base 106 is configured to mount to the upper end of the vertical upright 116. In the particular embodiment of the present invention shown in Figures 18 and 19, the base 106 comprises an insert or spigot configured to be received in an open end of a box section at the upper end of the vertical upright 116. The insert 106 may be secured to the upper end of the vertical upright 116 by one or more bolts. The insert or spigot may form part of the second or lower cam member 88 to mount the adjustable spacer to the top of the vertical upright. It may be formed as an integral part of the second or lower cam member 88 or may be fixed to the second or lower cam member 88. When attached to the top of the vertical upright, the insert or spigot physically prevents the second or lower cam member 88 from rotating while allowing the middle cam member 90 to rotate relative to the second cam member 88 when adjustments to the length of the adjustable spacer 80 are being made.

[0062] The mounting head 108 for mounting the grid structure 140 to the adjustable spacer 80 comprises a cap plate as described above with reference to FIG. 8 and is adapted to be mounted to the first cam member 86. In a particular embodiment of the invention shown in FIG. 19, the cap plate 108 comprises four connecting portions for connecting to the grid members 118, 120 at the nodes of the grid structure 140 by one or more bolts. The grid members 118, 120 shown in FIG. 20 comprise track supports 118, 120 to which tracks or rails 122a, 122b are attached. The track supports 118, 120 may be in the form of I-beams to provide the necessary structural support for the grid structure 140. The track supports 118, 120 are attached to the cap plate 108 by one or more bolts. The track supports 118, 120 are attached to the tracks 122a, 122b for guiding one or more loading devices on the grid structure 140 in a first direction and a second direction on the grid structure. Rather than the plug or insert of the cap plate being received directly into the top of the vertical upright as described above with reference to FIG. 8, the plug or insert is received within an opening in the first and intermediate cam members 86, 90. In a particular embodiment of the invention shown in FIGS. 19 and 20, the first and intermediate cam members 86, 90 have a ring-like or annular configuration to accommodate the plug or insert 106 of the cap plate 108. An optional slip ring may be interposed between the cap plate 108 and the first cam member 86 to facilitate rotation of the first cam member 86 relative to the cap plate 108. Because the adjustable spacer 80 is interposed between the top of the vertical upright 116 and the cap plate 108, a change in the length of the adjustable spacer (in this case the height of the adjustable spacer) as a result of rotation of the first and / or second indexing mechanisms 82, 84 changes the separation between the top of the vertical upright 116 and the cap plate 108 relative to the ground. This in turn varies the height of the grid structures 140 at the intersections or nodes 50 connected by the adjustable grid leveling mechanisms 104 .19 and 20 connecting the track supports 118, 120 at multiple nodes or intersections 50 of the grid structure 140, the level of the grid structure 140 can be adjusted at various points on the grid structure so that they are all in the same horizontal plane. For example, during operation, if any given area of ​​the grid structure is uneven, one or more of its corresponding adjustable grid features 104 at the nodes 50 of the grid structure 140 can be adjusted by rotating the first and / or second indexing mechanisms 82, 84 about their axes of rotation so that the grid structure in that given area is at the same level as the rest of the grid structure. To adjust the adjustable grid leveling mechanism 104, the first cam member 86 can be rotated in a first rotational direction about the rotational axis to provide a fine level adjustment of the height of the adjustable spacer 80, and / or the first cam member 86 can be rotated in an opposite second rotational direction about the rotational axis to provide a coarse level adjustment of the height of the adjustable spacer 80. Typically, a coarse level adjustment is first made by rotating the first cam member 86 in the second rotational direction about the rotational axis, followed by a fine level adjustment by rotating the first cam member 86 in the first rotational direction about the rotational axis.

[0063] 18-23 also show a plurality of teeth 112 on the outer periphery or rim of the first cam member 86, allowing the pinion 114 to engage or mesh with the plurality of teeth of the first cam member 86 outwardly. Rotating the pinion 114 in one rotational direction rotates the first cam member 86 in the same rotational direction about its axis of rotation, and rotating the pinion 114 in the opposite rotational direction rotates the first cam member 86 in the opposite rotational direction about its axis of rotation. The ability to rotate in the opposite rotational direction allows the level of the grid structure to be automatically adjusted with little or no manual intervention. The pinion 114 may be attached to an extendable arm or post having an extended configuration that engages the adjustable spacer 80, more specifically the first cam member 86, and a retracted configuration that disengages from the adjustable spacer 80, as shown in FIG. 21. Various means for providing an extendable arm are applicable in the present invention. For example, the extendable arm can be a linear actuator with a pinion attached. The linear actuator can be commanded to extend to engage the pinion with the adjustable spacer and retract to disengage the pinion from the adjustable spacer. Various other means for engaging the adjustable spacer, and more specifically the first cam member, are applicable in the present invention. For example, the pinion can be configured to engage with the inner edge of the ring-shaped first cam member, rather than the outer periphery as shown in FIG. 21. However, having multiple teeth on the outer periphery of the first cam member allows the pinion to easily engage multiple teeth of the first cam member by a simple downward movement between the grid members as shown in FIGS. 21 and 22. 20 also shows a locking bolt 124 extending through tracks 122a, 122b into adjustable grid leveling mechanism 104 for clamping first, second and intermediate cam members 86, 88, 90 together to prevent further rotation of the first, second and intermediate cam members relative to one another when an adjustment to the height of adjustable spacer 80 is made, i.e., the locking bolt locks the first, second and intermediate cam members together. The locking bolt includes a head that is engagable with a tool, such as a screwdriver.In the particular example shown in FIG. 22, the head of the fixing bolt 124 includes a slot for engagement with a blade-type screwdriver, although other head shapes are acceptable, for example a cross-shaped head.

[0064] A robotic grid leveling device or bot 126 operable on the grid structure 140 with an extendable pinion 114 can be commanded to selectively engage one or more adjustable spacers 80 at one or more nodes 50 of the grid structure 140. When an adjustment needs to be made to at least a portion of the grid structure, the robotic grid leveling device 126 can be commanded to move to at least a portion of the uneven grid structure 140 and adjust the height of one or more adjustable spacers 80 at one or more nodes 50 of the grid structure 140 until at least a portion of the grid structure is in a substantially horizontal plane and therefore at the same level as the remainder of the grid structure. Since the adjustable grid leveling mechanism 104 is interposed between the grid structure 140 and the vertical uprights 116 at the nodes or intersections of the grid structure, FIG. 23 shows an extendable arm with a pinion for engaging a first cam member of the adjustable spacer extended at one of the corners of the grid cell.

[0065] A variety of techniques can be used to identify areas of unevenness in the grid structure, all of which involve measuring the vertical position of a reference point on a robotic grid leveling device operable on the grid structure relative to one or more fixed reference points 128. For example, one or more total stations attached to one or more fixed reference points may be used to determine coordinates including the vertical position of the robotic grid leveling device on the grid structure. This includes measuring the angle the robotic grid leveling device makes relative to the one or more fixed reference points. The one or more fixed reference points may be attached to the grid structure and / or to fixed reference points near the grid structure, such as a building or a ceiling or a column.

[0066] In one exemplary embodiment of the present invention shown in FIG. 24, each of the one or more fixed reference points 128 on the grid structure 140 may comprise a light emitting unit for emitting light of at least one wavelength and a light receiving unit for receiving light reflected from a robotic grid leveling device operable on the grid structure. The light emitting unit is positioned at a known position and orientation relative to the light receiving unit to provide triangulation based on the position of the robotic grid leveling device on the grid structure. The robotic grid leveling device 126 comprises a light reflecting unit 130, e.g., a prism, for reflecting light emitted by the light emitting unit. During operation, the light emitted by the light emitting unit hits the light reflecting unit 130 where it is reflected by the light reflecting unit towards the light receiving unit. The deflection angle of the reflected light with respect to a horizontal object (defined herein as the "vertical angle") provides an indication of the vertical position of the robotic grid leveling device on the grid structure 140. The one or more fixed reference points 128 may be equipped with one or more robotic total stations for automatically measuring the angle of the light reflected from the light reflecting unit 130 of the robotic grid leveling device 126 relative to a horizontal axis. The vertical angle provides an indication of the vertical position of the robotic grid leveling device 126 on the grid structure 140, and therefore the level of the grid structure 140 at the measurement point. Light from the one or more robotic total stations may be commanded to illuminate the grid structure, and in particular the light reflecting unit 130 of the robotic grid leveling device, at different locations on the grid structure, thereby allowing the movement of the robotic grid leveling device on the grid structure to be tracked. As the robotic grid leveling device moves across the grid structure, the total stations at one or more of the fixed reference points 128 measure the vertical angle, and therefore the vertical position, of the robotic grid leveling device at one or more given grid cells of the grid structure. This is repeated as the robotic grid leveling device moves across successive grid cells.

[0067] Data of the vertical position of the robotic grid leveling mechanism at different points on the grid structure is provided to a control system that determines whether the grid structure is flat. The control system is configured to communicate with one or more total stations at fixed reference point 128 via a network. The one or more total stations may be wired or wirelessly coupled to the network. The network may comprise a local area network (LAN), a wide area network (WAN), or any other type of network. The control system comprises one or more processors, memory (e.g., read-only memory and / or random access memory), and a communication bus. The memory may be any storage device commonly known in the art, including, but not limited to, random access memory (RAM), computer readable media, magnetic storage media, optical storage media, or other electronic storage media that may be used to store data and accessed by a processor. One method of determining the level of the grid structure is by comparing the vertical positions of the robotic grid leveling device at different points on the grid structure. If there is a discrepancy between the vertical positions at different points on the grid structure, the control system can command the robotic grid leveling device to adjust the level of the grid structure at the measured point by engaging the pinion 114 with the adjustable grid leveling mechanism 104 and making coarse and / or fine adjustments of the adjustable spacers 80 described above until the vertical position of the robotic grid leveling device is within a predetermined level. For purposes of the present invention, the predetermined level can be the height of the grid structure relative to the ground. Thus, a feedback loop is established between the measurement data of the vertical position of the robotic grid leveling mechanism at different points on the grid structure from one or more fixed reference points 128 and the control system.The ability to engage the adjustable spacer at the grid level by lowering the pinion 114 into engagement with the adjustable spacer 80, and more specifically the first cam member 86, and making coarse and / or fine adjustments to the height of the adjustable spacer allows the robotic grid leveling device to automatically adjust the level of the grid structure.

[0068] Although the exemplary embodiment of the present invention describes one or more total stations at one or more fixed reference points 128 and a light reflecting unit 130 mounted on the robotic grid leveling apparatus, the reverse is also applicable where one or more total stations are mounted on the robotic grid leveling apparatus and the one or more fixed reference points comprise light reflecting devices, e.g., prisms, for reflecting light sent from the one or more total stations. In this way, light is sent by the robotic grid leveling apparatus operable on the grid structure and reflected from the light reflecting units at the one or more fixed reference points. The tilt angle that the light makes with respect to the horizontal provides an indication of the vertical position of the robotic grid leveling apparatus and therefore the level of the grid structure.

[0069] To provide an indication of an adjustment made to the length of the adjustable spacer, the first cam member 86 and / or the second cam member 88 and / or the intermediate cam member 90 may be provided with one or more markers (not shown) that may be used to measure the relative angular position of any one of the first, second, and intermediate cam members with respect to one another. Because the second cam member 88 is fixed, in one exemplary embodiment, the relative angular position of the first cam member 86 and / or the intermediate cam member 90 with respect to the second cam member 88 is measured to provide an indication of the length or height of the adjustable spacer 80. For example, the angular position of the first cam member 86 with respect to the second cam member 88 provides an indication of the degree of rotation in a first rotational direction about the axis of rotation of the first cam member 86, and therefore the length of the adjustable spacer. Because the first cam member 86 provides rotation in the opposite “second” rotational direction, the angular position of either the first cam member 86 and / or the intermediate cam member 90 relative to the second cam member 88 can provide an indication of the adjustment made to the length of the adjustable spacer as the intermediate cam member 90 rotates relative to the second cam member 88.

[0070] The process of measuring and adjusting the level of a grid structure may be further illustrated in an exemplary embodiment of the present invention shown in the flow chart of FIG. 25. The robotic grid leveling device is commanded to move to a first grid cell and determine the coordinates of the robotic grid leveling device at the first grid cell by the total station described above, which includes measuring the vertical position of the robotic grid leveling device at the first grid cell (170). Once the vertical position of the robotic grid leveling device at the first cell is known, the robotic grid leveling device is commanded to move to a second grid cell and measure the vertical position of the robotic grid leveling device at the second grid cell (172). A control system in communication with the total station records the coordinates of the robotic grid leveling device at the first and second grid cells and determines the difference between the vertical positions of the robotic grid leveling device at the first and second grid cells (174). If the portions of the grid cells covering the first and second grid cells are uneven, there will be a discrepancy between the measurements of the vertical positions of the robotic grid leveling device at the first and second grid cells. The control system determines (176) whether this discrepancy exceeds a predetermined value, and if so, the control system commands the robotic grid leveling device to make adjustments of the adjustable spacers at the nodes of the second grid cell until the measured coordinates, particularly the vertical position, of the robotic grid leveling device at the second grid cell are such that the discrepancy falls below the predetermined value (178). The entire process of measuring and adjusting the grid levels is repeated for other grid cells (180).

[0071] In one example, the grid structure is within predetermined upper and lower limits as measured from the vertical position of the robotic grid leveling device on the grid structure. If the vertical position of the robotic grid leveling device is outside of the predetermined upper and lower levels, the level of the grid structure is adjusted. In another example of the invention, the level of the grid structure is set to a predetermined level or height and the measurements of the robotic grid leveling device are compared to this set level or height. If there is a discrepancy, the robotic grid leveling device makes adjustments to one or more adjustable spacers at one or more nodes such that the level or height of the grid structure is at the predetermined level or height or within the upper and lower limits of the predetermined level.

[0072] Ideally, the second grid cell is adjacent to the first grid cell. This has the advantage that the robotic grid leveling device makes adjustments to the grid structure at successive nodes of the grid structure as it moves across the grid structure. Adjustments to the level of the grid structure may be made as the grid members of the grid structure are assembled onto the vertical uprights. Alternatively, measurements and adjustments of the grid level may be made after the grid frame structure is assembled.

[0073] An adjustable grid leveling mechanism with adjustable spacers at the top of the vertical uprights may be used in conjunction with a second adjustable grid leveling mechanism at the bottom of the vertical uprights. For example, an initial adjustment of the level or height of the grid structure may be made at the base or bottom of the vertical uprights, followed by a final adjustment of the grid level to ensure that the grid structure is in a substantially horizontal plane. Measurements and / or adjustments of the level of the grid structure may be made at intervals to ensure that the grid structure is substantially flat. Thermal expansion of various components of the grid framework structure, such as the vertical uprights and / or grid members, may distort the grid structure, resulting in unevenness in the grid structure. Periodic measurements of the level of the grid structure by the robotic grid leveling device may allow adjustments of the level of the grid structure to be made as necessary to ensure that the grid structure is within a predetermined level.

[0074] Although specific embodiments of the invention have been disclosed, it is understood that the invention as defined in the claims is not limited to the specific embodiments disclosed, and that many modifications and other embodiments are intended to be within the scope of the appended claims. Furthermore, it is contemplated that features of one embodiment may be combined or used with features from different embodiments. For example, the adjustable spacer is not limited to only two indexing mechanisms, each indexing mechanism providing a different adjustment of the length of the adjustable spacer, but may include any number of indexing mechanisms. Furthermore, each indexing mechanism may provide a different adjustment of the length of the adjustable spacer for a given angular rotation about a coaxial axis of rotation, or may provide the same adjustment of the length of the adjustable spacer.

Claims

1. 1. An adjustable spacer for adjusting a distance between two objects, comprising: i) a first rotatable indexing mechanism configured to rotate in a first rotational direction about an axis of rotation; ii) a second rotatable indexing mechanism configured to rotate about said axis of rotation in a second rotational direction, wherein said second rotational direction is opposite to said first rotational direction; Equipped with The first and second rotatable indexing mechanisms are configured to change a length of the adjustable spacer along the axis of rotation by a first length when the first rotatable indexing mechanism rotates a given angular rotation in the first rotational direction about the axis of rotation, and to change a length of the adjustable spacer along the axis of rotation by a second length when the second rotatable indexing mechanism rotates the same given angular rotation in the second rotational direction about the axis of rotation, the second length being the same or different from the first length.

2. The adjustable spacer of claim 1 , wherein the first length is less than the second length.

3. i) a first cam member rotatable about the rotation axis, the first cam member having a first mating surface; ii) a second cam member rotatable about the rotation axis, the second cam member having a second mating surface; and iii) an intermediate cam member interposed between the first cam member and the second cam member, the intermediate cam member being rotatable about the axis of rotation and having a first intermediate mating surface for engaging with the first mating surface to provide the first rotatable indexing mechanism and a second intermediate mating surface for engaging with the second mating surface to provide the second rotatable indexing mechanism; Equipped with the first intermediate mating surface and each mating surface of the first mating surface have a contour or profile with a variable thickness in a circumferential direction such that a length of the adjustable spacer along the axis of rotation changes by the first length when the first cam member rotates in the first rotational direction about the axis of rotation relative to the intermediate cam member through the given angular rotation, and the second intermediate mating surface and each mating surface of the second mating surface have a contour or profile with a variable thickness in a circumferential direction such that a length of the adjustable spacer along the axis of rotation changes by the second length when the intermediate cam member rotates in the second rotational direction opposite the first rotational direction about the axis of rotation relative to the second cam member through the same given angular rotation. An adjustable spacer according to claim 1 or 2.

4. 4. The adjustable spacer of claim 3, wherein the contour or profile of each of the first intermediate mating surface and the first mating surface is configured to prevent the first cam member from rotating in the second rotational direction relative to the intermediate cam member, and the contour or profile of each of the second intermediate mating surface and the second mating surface is configured to prevent the intermediate cam member from rotating in the first rotational direction relative to the second cam member.

5. 5. An adjustable spacer as claimed in claim 3 or 4, wherein the first intermediate mating surface and the first mating surface each include a plurality of teeth to provide the first rotatable indexing mechanism, and the second intermediate mating surface and the second mating surface each include a plurality of teeth to provide the second rotatable indexing mechanism.

6. 6. The adjustable spacer of claim 5, wherein each of said plurality of teeth of said first and second rotatable indexing mechanisms is wedge shaped.

7. the mating surface of each of the first intermediate mating surface and the first mating surface includes at least one first type of ramp, the at least one first type of ramp being inclined to change a length of the adjustable spacer along the axis of rotation by the first length when the first cam member rotates through the given angular rotation in the first rotational direction relative to the intermediate cam member; the mating surface of each of the second intermediate mating surface and the second mating surface includes at least one second type of ramp, the at least one second type of ramp being inclined to change a length of the adjustable spacer along the axis of rotation by the second length when the intermediate cam member rotates through the given angular rotation in the second rotational direction relative to the second cam member; An adjustable spacer according to any one of claims 3 to 6.

8. 8. The adjustable spacer of claim 7, wherein the at least one first and / or second type ramp comprises three or more ramps.

9. 9. An adjustable spacer according to claim 7 or 8, wherein the at least one first type ramp is shallower than the at least one second type ramp.

10. 10. An adjustable spacer as claimed in any one of claims 3 to 9, wherein the first and second intermediate mating surfaces cooperate with the first and second mating surfaces, respectively, to rotate the intermediate cam member in the second rotational direction relative to the second cam member when the first cam member rotates in the second rotational direction.

11. 11. The adjustable spacer of claim 10, wherein said first cam member includes a plurality of teeth extending outwardly about a periphery of said first cam member for engaging a pinion.

12. An adjustable spacer according to any one of claims 3 to 11, wherein the first cam member and the intermediate cam member are each ring-shaped.

13. 13. An adjustable spacer according to any one of claims 3 to 12, wherein each of the first and second cam members and the intermediate cam member is provided with at least one marker for measuring the position of any one of the first cam member and / or the intermediate cam member and / or the second cam member relative to each other.

14. 14. An adjustable grid levelling mechanism for adjusting the level of a grid structure of a grid framework structure comprising a plurality of vertical uprights supporting said grid structure, said adjustable grid levelling mechanism comprising a base for mounting to tops or upper ends of the vertical uprights, a mounting head on which a grid structure is mounted, and an extensible section interposed between the base and the mounting head such that the mounting head is moveable relative to the base, said extensible section comprising an adjustable spacer according to any one of claims 1 to 13.

15. 15. The adjustable grid leveling mechanism of claim 14, wherein the base includes a spigot or insert for attachment to a vertical upright.

16. 16. The adjustable grid levelling mechanism of claim 14 or 15, wherein the mounting head comprises a rail cross member having four right-angled ends, each of the four right-angled ends configured to support a separate grid member in a grid pattern.

17. 1. A grid framework structure configured to support one or more load handling devices, comprising: i) a grid structure comprising a first set of grid members extending in a first direction and a second set of grid members extending in a second direction, the second set of grid members extending transversely to the first set of grid members in a substantially horizontal plane and in a grid pattern comprising a plurality of grid cells; ii) a plurality of vertical uprights for supporting said grid structure, said plurality of vertical uprights being interconnected at upper ends of said plurality of vertical uprights by said first set of grid members and said second set of grid members; iii) an adjustable grid levelling mechanism according to any one of claims 14 to 16 interposed between at least one of the plurality of vertical uprights and the grid structure at one or more of the interconnections of the plurality of vertical uprights; wherein the adjustable spacer is configured to adjust a vertical distance between the at least one of the plurality of vertical uprights and the grid structure.

18. 20. The grid framework structure of claim 17, wherein the plurality of vertical uprights are arranged to form a plurality of vertical storage locations for one or more containers to be stacked between and vertically guided by the plurality of vertical uprights.

19. 19. A grid framework structure according to claim 17 or 18, wherein the grid structure is attached to the adjustable grid levelling mechanism at one or more of the interconnections of the plurality of vertical uprights.

20. 20. A robotic grid levelling device for moving over the grid structure of any one of claims 17 to 19, comprising: A) a wheel assembly comprising: i) a first set of wheels for moving said robotic grid leveling device in said first direction; ii) a second set of wheels for moving the robotic grid leveling device in the second direction; A) a wheel assembly; B) a drive mechanism for selectively driving the first and / or second sets of wheels; and C) an adjustment tool configured to rotate the first and / or second rotatable indexing mechanisms about their respective first and second rotational directions; A robotic grid leveling device comprising:

21. 21. The robotic grid leveling device of claim 20, wherein the adjustment tool comprises a pinion for engaging the first and / or second rotatable indexing mechanisms.

22. A method for levelling a grid structure of a grid framework structure according to any one of claims 17 to 19, comprising the steps of: i) measuring a first vertical position of a robotic grid levelling device according to claim 20 or 21 in a first grid cell of the grid structure relative to one or more fixed reference points; ii) moving the robotic grid leveling device on the grid structure to a second grid cell on the grid structure; iii) measuring a second vertical position of the robotic grid leveling device on the grid structure in the second grid cell relative to the one or more fixed reference points; iv) calculating a difference between the second vertical position and the first vertical position; This means, v) if the calculated difference is greater than a predetermined value, adjusting a length of the adjustable spacer by engaging the adjustable tool with the adjustable spacer to rotate the first and / or second rotatable indexing mechanisms in their respective first and / or second rotational senses about the axis of rotation until the calculated difference is less than the predetermined value; vi) repeating steps (i) to (v) until the grid structure is substantially horizontal; A method comprising:

23. The method of claim 22 , wherein the one or more fixed reference points are located at one or more corners of the grid structure.

24. 24. The method of claim 22 or 23, wherein the first and second vertical positions of the robotic grid leveling device are measured by one or more total stations at the one or more fixed reference points, each of the one or more total stations comprising a transmitter device for illuminating the robotic grid leveling device with light of at least one wavelength and a receiver device for receiving light reflected from the robotic grid leveling device.

25. 1. A grid leveling system comprising: i) a grid framework structure according to any one of claims 17 to 19; ii) a robotic grid levelling device according to claim 20 or 21 operating on the grid structure of the grid framework structure; and iii) a control system comprising one or more processors and a memory having instructions stored therein; the instructions, when executed by the one or more processors, cause the one or more processors to: a) measuring a first vertical position of the robotic grid leveling device on the grid structure at a first grid cell on the grid structure relative to one or more fixed reference points on the grid structure; b) moving the robotic grid leveling device to a second grid cell on the grid structure; c) measuring a second vertical position of the robotic grid leveling device in the second grid cell on the grid structure relative to the one or more fixed reference points on the grid structure; d) calculating a difference between said second vertical position and said first vertical position; e) if the calculated difference is greater than a predetermined value, adjusting a length of the adjustable spacer by engaging the adjustable tool with the adjustable spacer to rotate the first and / or second rotatable indexing mechanisms in their respective first and second rotational directions about the axis of rotation until the calculated difference is less than the predetermined value; A grid leveling system that allows you to

Images