Self-lifting robotic device movable in desired horizontal directions

A robotic device movable in a vertical direction and in prescribed horizontal directions along rails arranged in the prescribed horizontal directions in multiple rows provided at various levels with respect to ground. The robotic device has a frame, wheels coupled to the frame and configured for moving the frame along the rails, and support handles for lifting the frame in the vertical direction from first rails arranged in a first row of the rails to second rails arranged in a second row of the rails. The support handles are configured for providing engagement with the second rails to lift the robotic device in the vertical direction, and for turning the frame into a desired horizontal direction by pushing against the second rails on an intersection between the second rails and third rails arranged in the same row as the second rails.

TECHNICAL FIELD

This disclosure relates to robotics, and more particularly, to a self-lifting robotic device that can move in any desired horizontal directions and can move in a vertical direction without assistance of external lifts.

BACKGROUND ART

Conventional robotic systems include lifts provided for moving robotic devices in a vertical direction. However, the number of lifts in any efficient robotic system employing multiple robots is substantially less than the number of robots. Therefore, “bottlenecks” are created near the lifts, reducing the throughput of the robotic system.

Therefore, there is a need for a new “self-lifting” technique that would enable a robotic device to move in a vertical direction without assistance of an external lift.

A robotic system may be installed in a retail storage facility or warehouse, in which robotic devices would provide access to multiple storage racks. When the retail storage facility or warehouse is provided in an existing building, the storage racks need to be installed in directions defined by walls of rooms in this building. If a room has a non-rectangular shape, one storage rack section has to be installed along a direction which is not orthogonal with respect to a direction of another storage rack section.

To provide access to storage rack sections arranged in non-orthogonal directions, there is a need for a robotic device capable of moving not only in mutually perpendicular horizontal directions, but in any desired horizontal directions.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect, the present disclosure offers a robotic device movable in a vertical direction and in prescribed horizontal directions along rails arranged in the prescribed horizontal directions in multiple rows provided at various levels with respect to ground. The robotic device has a frame, wheels coupled to the frame and configured for moving the frame along the rails, and support handles for lifting the frame in the vertical direction from first rails arranged in a first row of the rails to second rails arranged in a second row of the rails.

The support handles are configured for providing engagement with the second rails to lift the robotic device in the vertical direction, and for turning the frame into a desired horizontal direction by pushing against the second rails on an intersection between the second rails and third rails arranged in the same row as the second rails.

In accordance with an exemplary embodiment, the support handles may be provided on a platform movable in the vertical direction and configured for transferring the frame in the vertical direction when the support handles are engaged with the second rails. Each of the support handles may include an L-shaped pin attached to the movable platform.

In particular, the support handles may be configured for raising the frame with respect to the second rails when the support handles pushes against the second rails.

The robotic device may further have a wheels turning mechanism for turning the wheels with respect to a direction of the second rails when the frame is raised with respect to the second rails.

The wheels turning mechanism may be configured for turning the wheels by angles determined based on dimensions of the robotic device so as to position the wheels for movement along an auxiliary rail provided at the intersection between the second rails and the third rails. The wheels may be placed onto the auxiliary rail when the support handles stop pushing against the second rail.

The frame may be controlled to move along the auxiliary rail until the wheels reach intersection points where the auxiliary rail meets the third rails. The support handles may be configured to push against the third rails when the wheels reach the intersection points where the auxiliary rail meets the third rails.

The support handles may raise the frame with respect to the third rails when the support handles push against the third rails, and the wheels turning mechanism may turn the wheels with respect to the auxiliary rail to position the wheels for movement along the third rails.

In accordance with a further aspect, a method is offered for operating a robotic device having a frame with wheels, and support handles. The method involves:rotating the wheels for moving the frame on first rails in a first horizontal direction,engaging the support handles with second rails arranged in the first horizontal direction above the first rails,moving the frame in a vertical direction using the support handles engaged with the second rails so as to place the wheels on the second rails,rotating the wheel for moving the frame on the second rails to an intersection between the second rails and third rails arranged in a second horizontal direction,operating the support handles to push against the second rails so as to raise the frame above the second rails, andturning the wheels to move the frame onto the third rails.

The method may further include the step of turning the wheels with respect to a direction of the second rails when the frame is raised with respect to the second rails. The wheels may be turned by angles determined based on dimensions of the robotic device to position the wheels for movement along an auxiliary rail provided at the intersection between the second rails and the third rails. The wheels may be placed onto the auxiliary rail when the support handles stop pushing against the second rail.

The frame may be controlled to move along the auxiliary rail until the wheels reach intersection points where the auxiliary rail meets the third rails.

Pushing against the third rails using the support handles may be performed when the wheels reach the intersection points where the auxiliary rail meets the third rails. The frame may be raised with respect to the third rails when the support handles push against the third rails, so as to enable the wheels to turn with respect to the auxiliary rail to position the wheels for movement along the third rails.

Additional advantages and aspects of the disclosure will become readily apparent to those skilled in the art from the following detailed description, wherein embodiments of the present disclosure are shown and described, simply by way of illustration of the best mode contemplated for practicing the present disclosure. As will be described, the disclosure is capable of other and different embodiments, and its several details are susceptible of modification in various obvious respects, all without departing from the spirit of the disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as limitative.

DETAILED DISCLOSURE OF THE EMBODIMENTS

The present disclosure will be made using exemplary embodiments described in the present disclosure. It will become apparent, however, that the concept of the disclosure is applicable to any robotic device movable in arbitrary horizontal directions.

FIG. 1shows an exemplary embodiment of a robotic device10of the present disclosure. The robotic device10may move along a pair of rails12that extends in a horizontal direction.FIG. 1shows only rails extending in a single horizontal direction. However, as discussed later, the robotic system of the present disclosure may also include horizontal rails arranged at a desired angle with respect to a direction of the rails12shown inFIG. 1. As discussed below, the robotic device10may move along the rails arranged in any desired horizontal directions.

The rails12may be arranged in multiple rows arranged in a vertical direction on different levels with respect to the ground.FIG. 1shows a pair of rails12on which the robotic device10currently stands, and a pair of rails14arranged in the next row above the rails12. For example, the rails12and14may be L-shaped rails.

The robotic device10may have a frame16with four wheels18attached to the frame16. The frame16may be formed as a braced structure for supporting elements required to operate the robotic device10. Each wheel18may be attached to the frame16so as to rotate in a vertical plane about an axis extending from the center of the wheel18in order to move the robotic device10along the rails.

Four vertical pivots20may be used for attaching the respective wheels18to the frame so as to turn each wheel18in a horizontal plane about the vertical axis of the respective pivot20. For example, each wheel18may be turned in a horizontal plane about 90 degrees with respect to the direction of rails. Each vertical pivot20is arranged with respect to the frame16so as to make the width of the robotic device10with the wheels18, smaller than a distance between adjacent rails in a direction perpendicular to the direction of the rails, when the wheels18are turned into the direction perpendicular to the direction of the rails.

As discussed below, the wheels18may be turned in a horizontal plane to support moving the robotic device10in the vertical direction, and to support turning the robotic device10to a horizontal direction perpendicular to a current horizontal direction of the robotic device10. Although in an exemplary embodiment, the robotic device10has four wheels18, one skilled in the art would realize that the present concept is applicable to any number of wheels that can be provided to support movement of the robotic device10.

The frame16may hold a movable platform22that can be used for carrying loads such as goods delivered by the robotic device10in a robotic retail environment. For example, the platform22may be a rectangular metal plate configured to accommodate boxes or pallets with goods. Side walls24may be provided on the frame16to support carrying loads.

As discussed below, the platform22may be moved in a vertical direction to support vertical movements of the robotic device10. Platform lifting mechanisms26may be arranged on the side walls24for moving the platform22up or down in a vertical direction. For example, as shown inFIG. 1, each platform lifting mechanism26may be implemented using a belt drive.

Deployable support handles28may be attached to the platform22.FIG. 1shows the support handles28held in an undeployed state in slots formed on the platform22. As discussed below, the support handles28may be L-shaped pins extended from the platform22to support moving the robotic device10in a vertical direction and changing a horizontal direction of the robotic device10.

FIG. 2is a simplified diagram that illustrates elements for performing various operations performed by the robotic device10. The operations of the robotic device10are controlled by a controller102that may include a data processor responsive to external commands for processing the commands and producing various control signals. The controller may have a radio transceiver for providing bidirectional data communications with external objects via a radio network, such as a WiFi network. A controller area network (CAN) bus may connect the controller102with various elements of the robotic device10to supply control signals to the elements of the robotic device10and receive responses.

In particular, the controller102may control a wheels rotation drive104, a wheels turning drive106, a platform lifting mechanisms drive108, and a support handles drive110. The wheels rotation drive104, wheels turning drive106and platform lifting mechanisms drive108may be arranged on the frame16, whereas the support handles drive110may be arranged on the movable platform22. The wheels rotation drive104is provided for driving the wheels18so as to rotate them in a vertical plane in order to move the robotic device10along the rails in a horizontal direction. The wheels turning drive106drives the vertical pivots20so as to turn the respective wheels18in a horizontal plane. The wheels18may be turned 90 degrees about the vertical axes of the pivots20. As one skilled in the art would realize, the wheels drives104and106may be implemented using any of well known mechanisms for rotating and turning wheels.

The platform lifting mechanisms drive108is provided for driving the platform lifting mechanisms26that move the platform22up and down in a vertical direction. As one skilled in the art would realize, the platform lifting mechanisms26and drive108may be implemented using any well known mechanisms for moving a plate up and down.

The support handles drive110is used for extending the support handles28from the slots on the platform22when the support handles28are required for supporting movements of the robotic device10, and for hiding the support handles28back into the slots on the platform22when the support handles28are no longer required. The drive110may be implemented using any well known mechanism for extending a pin.

FIGS. 3-9illustrate operations performed by the robotic device10when it moves in a vertical direction. In particular,FIG. 3shows a robotic device10having its wheels18standing on the lower rails12. The platform22may be positioned on the frame16. As illustrated inFIG. 4, at the beginning of the vertical movement, the controller102may control the platform lifting mechanisms drive108to activate the platform lifting mechanisms26at the both side walls24so as to raise the platform22to a level above the rails14provided in the next row of the rails with respect to the rails12.

As shown inFIG. 5, after the platform22is raised to a desired level above the rails14or simultaneously with raising the platform22, the support handles drive110is controlled to deploy the support handles28. The deployment of the support handles28may be provided by extending each of them from the respective slot on the platform22to a position directly above the respective rail14.

For example, each support handle28may be implemented as an L-shaped support pin28shown inFIG. 5. During the deployment, the support pin28may be extended and placed directly above the respective rail14. Thereafter, the platform22is lowered to a lower position so as to engage each support pin28with the respective rail14and raise the frame16with respect to the rails12to a level sufficient to disengage the wheels from the rails12.

As shown inFIG. 6, when the wheels18become disengaged from the rails12, the wheels turning drive106is controlled so as to turn each of the wheels18in a horizontal plane using the respective vertical pivots20. For example, each wheel18may be turned about the vertical axis of the pivot20by an angle equal to approximately 90 degrees. The position of the vertical pivots20with respect to the frame16is selected so as to provide the maximum distance between the edges of the turned wheels18in a direction perpendicular to the direction of the rails, smaller than the distance between the rails in the horizontal direction.

As shown inFIG. 7, the support handles28fix the platform22on the rail14so as to enable the platform lifting mechanisms26to lift the frame16when the platform lifting mechanisms26is controlled by the platform lifting mechanisms drive108to reduce the distance between the platform22and the frame16in a vertical direction. The frame16may be lifted to a level above the rails14so as to place the platform22on the frame16. As the distance between the edges of the turned wheels18is less than the distance between the rails14in a direction perpendicular to the direction of the rails14, the frame16with the wheels18can be transferred in the space between a pair of the horizontal rails14.

As shown inFIG. 8, when the frame16is raised to a desired position above the rails14, the wheel turning drive106is controlled to turn the wheels18using the respective vertical pivots20so as to return each wheel18to an initial position along the rails.

Thereafter, as shown inFIG. 9, the support handles28may be removed from the rails14and placed in the respective slots on the platform22. As a result, the frame16is lowered so as to place the wheels18on the rails14.

Hence, the robotic device10standing on lower rails12can lift itself in a vertical direction to a level of higher rails14in the next row of rails so as to continue movement along the rails14. As one skilled in the art would realize, a similar technique can be used to move the robotic device10down in a vertical direction from higher rails14to lower rails12in the next row of the rails. No external lifting device is required for moving the robotic device up or down in a vertical direction.

FIG. 10illustrates an exemplary floor plan of a storage facility, in which the robotic device10may operate. The storage facility may have multiple storage racks204, each of which includes storage cells206arranged in multiple horizontal rows and multiple vertical columns.FIG. 10shows a storage facility arranged in a non-rectangular space. To accommodate a non-rectangular space, sections of the storage racks204may be arranged along various horizontal directions including mutually non-orthogonal directions.

Pairs of horizontal rails208and210may be arranged in horizontal rows corresponding to the rows of the storage cells206, at different levels with respect to the ground corresponding to the columns of the storage cells206. The horizontal rails208and210may be arranged at any desired angle with respect to each other. The angle between the rails208and210may differ from 90 degrees and may be selected based on the arrangement of the storage racks204so as to provide the robotic device10with access to storage cells206of all storage racks204.

Rail intersections212are arranged at places where the rails208and210meet. Circular rails214may be provided at the intersections212to enable the robotic device to move between the rails208and210. Also, the robotic system may include rails216perpendicular to the rails208and rails218perpendicular to the rails210for enabling the robotic device10to move in a horizontal direction from one pair of the rails208to the other, and from one pair of the rails210to the other.

FIGS. 11-18illustrate operations performed by the robotic device10to turn from one horizontal direction to another horizontal direction. For example,FIG. 10schematically shows the robotic device10moving along the rails208to the intersection212with the rails210. As shown inFIG. 11, the robotic device10may be controlled by the controller102to stop at the intersection212so as to position the wheels18of the robotic device10at the circular rail214.

As shown inFIG. 12, when the robotic device10is stopped, the support handle drive110is controlled to deploy the support handles28. The deployment of the support handles28may be provided by extending them so as to push against the rail208. When the support handles28push against the rails208, the robotic device10becomes slightly raised above the rails208so as to disengage the wheels18from the rails208.

As shown inFIG. 13, when the wheels18are disengaged from the rails208, the wheels turning drive106is activated to turn the wheels18in a horizontal plane using the vertical pivots20. Each wheel18may be turned by an angle determined based on the dimensions of the robotic device10to position the wheels18for movement along the rail214.

For example, if the width and the length of the robotic device10are about the same, the wheels18may be turned approximately 45 degrees about the vertical axes of the pivots20. As shown inFIG. 13, the wheels18positioned above each rail208may be turned in opposite direction—one of the wheels18may be turned in a clockwise direction by approximately 45 degrees, while the other wheel18above the same rail may be turned in a counter-clockwise direction by approximately 45 degrees.

As shown inFIG. 14, after the wheels18are turned in a horizontal plane, the support handles drive110is controlled to remove the support handles28. As a result, the wheels18are placed onto the circular rail214so as to enable the robotic device10to move along the rail214.

As shown inFIG. 15, the robotic device10may move along the rail214until the wheels18reach the intersection points where the rail214meets the pair of rails210. As shown inFIG. 16, when these intersection points are reached, the controller102controls the support handles drive110to deploy the support handles28so as to engage them with the rails210. When the support handles28push against the rails210, the robotic device10becomes slightly raised above the rail214so as to disengage the wheels18from the rail214.

As shown inFIG. 17, when the wheels18are disengaged from the rails214, the wheels turning drive106is controlled to turn the wheels18in a horizontal plane using the pivots20so as align the wheels18with the rails210. Thereafter, as shown inFIG. 18, the support handles drive110is controlled to remove the support handles28so as to place the robotic device10on the rails210. As a result, the robotic device10is enabled to move along the rails210.

Hence, the support handles28configured for self lifting the robotic device10in a vertical direction are also configured to enable the robotic device10to turn between any desired horizontal directions so as to have access to the storage stacks204arranged along different horizontal directions.

FIGS. 11-18illustrate turning the robotic device10between mutually non-orthogonal horizontal directions of the rails208and210. However, as one skilled in the art would realize, the support handles28may enable the robotic device10to turn into a perpendicular horizontal direction, for example, when the robotic device10turns from the rails208to the rails216inFIG. 10. Turning the robotic device into a perpendicular direction is discussed in more detail in my copending U.S. patent application Ser. No. 13/546,492 filed on Jul. 11, 2012 entitled “ROBOTIC DEVICE MOVABLE IN THREE MUTUALLY PERPENDICULAR DIRECTIONS” and incorporated herewith by reference.

The foregoing description illustrates and describes aspects of the present invention. Additionally, the disclosure shows and describes only preferred embodiments, but as aforementioned, it is to be understood that the invention is capable of use in various other combinations, modifications, and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein, commensurate with the above teachings, and/or the skill or knowledge of the relevant art.

The embodiments described hereinabove are further intended to explain best modes known of practicing the invention and to enable others skilled in the art to utilize the invention in such, or other, embodiments and with the various modifications required by the particular applications or uses of the invention. Accordingly, the description is not intended to limit the invention to the form disclosed herein.