Remotely controlled vehicle assembly for picking up storage containers from a storage system

Abstract

The invention relates to a remotely controlled vehicle assembly for picking up storage containers from a storage system and a method for changing vehicle direction.The vehicle assembly comprises a vehicle body having a cavity adapted to receive a storage container stored within the storage system, a vehicle hoist coupled at least indirectly to the vehicle body and adapted to lift the storage container into the cavity, a displacement arrangement comprising, among other things, a displacement motor configured to at least generate the force necessary to displace one or both of a first set of vehicle rolling means and a second set of vehicle rolling means between a displaced state in which the respective vehicle rolling means is displaced away from the underlying storage system during use, and a non-displaced state in which the respective vehicle rolling means is in contact with the underlying storage system during use, and drive means coupled to the displacement arrangement.The drive means further comprises the first set of vehicle rolling means coupled to the vehicle body and allowing movement of the vehicle along a first direction (X) in the storage system during use and the second set of vehicle rolling means coupled to the vehicle body and allowing movement of the vehicle along a second direction (Y) in the storage system during use, where the second direction (Y) is perpendicular to the first direction (X).

Description

Technical Field:

[0001] The present invention relates to a remotely controlled vehicle assembly for picking up storage containers from a storage system as defined in the preamble of claim 1, a storage system for storing containers and a method for changing the direction of the vehicle. Known technique:

[0002] A remotely controlled vehicle for picking up storage containers from a storage system is known. A detailed description of a relevant prior art storage system is set out in WO 98 / 49075, and details of a prior art vehicle suitable for such a storage system are set out in Norwegian patent N0317366. Such a prior art storage system comprises a three-dimensional storage grid containing storage containers stacked on top of each other up to a certain height. The storage grid is normally constructed as aluminium columns interconnected by top rails, and a number of remotely controlled vehicles, or robots, are arranged to move laterally on these rails. Each robot is equipped with a lift for picking up, bringing and placing containers stored in the storage grid, and a rechargeable battery for supplying electrical power to a motor integrated in the robot.The robot typically communicates with a control system via a wireless link and is recharged at a charging station when necessary, typically at night.

[0003] WO2013167907 describes a storage system that is made up of a frame with a plurality of containers stacked on top of each other. Handling devices are positioned above the frame and can be moved to access different stacks.

[0004] An example of a prior art storage system is illustrated in Figure 1. The storage system 3 includes multiple vehicles or robots 1 configured to move on a dedicated container elevator device 50, the latter being arranged to receive a storage container 2 from the robot 1 at the top level of the storage system 3 and to transport the storage container 2 down in a vertical direction to a receiving station, or gate 60.

[0005] However, with this known system, each vehicle covers a cross-section of the underlying storage system corresponding to two storage columns, thus limiting the maximum number of simultaneously operating vehicles.

[0006] It is therefore an object of the present invention to provide a vehicle assembly, a storage system and a method for operating such a vehicle assembly which allows a significant increase in the number of simultaneously operating vehicles during a successful handling of storage containers. Summary of the invention:

[0007] The present invention is set forth and characterized by the independent claims, while the dependent claims describe other characteristics of the invention.

[0008] In particular, the invention relates to a remotely controlled vehicle assembly suitable for picking up storage containers from a storage system. The vehicle assembly comprises a vehicle body having a cavity suitable for receiving a storage container stored within the storage system, a vehicle lift device coupled at least indirectly to the vehicle body and suitable for lifting the storage container into the cavity, a displacement arrangement comprising, among other things, a displacement motor configured to at least generate the force necessary to displace one or both of a first set of vehicle rolling means and a second set of vehicle rolling means between a displaced state in which the respective vehicle rolling means is displaced away from the underlying storage system in use, and a non-displaced state in which the respective vehicle rolling means is in contact with the underlying storage system in use, and drive means coupled to the displacement arrangement.The drive means further comprises a first set of vehicle rolling means coupled to the vehicle body and permitting movement of the vehicle along a first direction (X) in the storage system during use and a second set of vehicle rolling means coupled to the vehicle body and permitting movement of the vehicle along a second direction (Y) in the storage system during use, wherein the second direction (Y) is perpendicular to the first direction (X). The motor providing the necessary force to propel the vehicle assembly in the X or Y direction may be one or more dedicated motors and / or the displacement motor. The vehicle assembly is further characterised in that the displacement motor is located in a lateral plane above the cavity, and further configured to generate a force which is converted by the remaining components of the displacement arrangement into a vertically directed thrust force acting on the first or second set of vehicle rolling means.The lateral plane is hereinafter defined as any plane arranged parallel to the plane formed by the first (X) and second (Y) directions. Furthermore, the vertical direction, or Z direction, is defined as the direction perpendicular to the lateral plane. The cavity may be defined by dedicated plates and / or by the surrounding components constituting the displacement arrangement and the drive means.

[0009] In a preferred embodiment, the transmission of power from the displacement motor to the corresponding vehicle rolling means is performed by means of at least one lever configured to allow mechanical switching between the displaced state and the non-displaced state.

[0010] In another preferred embodiment, at least one of the vehicle rolling means comprises a first part and a second part arranged on opposite side walls of the vehicle body and a vertically displaceable rod rigidly connecting the first part and the second part across the cavity, or at least at an upper half of the vehicle body. The rod may advantageously be arranged parallel to the aforementioned lateral plane.

[0011] In another preferred embodiment, the displacement arrangement comprises at least one lever arm configured to abut the vertically displaceable rod during operation of the displacement motor. Said at least one lever arm may be arranged at least partially below the vertically displaceable rod, at the side or above the cavity. The area where the lever arm abuts the rod is preferably at or near the longitudinal center of the arm. The term 'at least partially below' means an arrangement of the lever arm which results in an abutment point which is located below the rod relative to any underlying bearing system. The at least one lever arm may advantageously be arranged at an upper half of the vehicle body. Furthermore, they may be arranged either above or along the sides of the cavity, or both.

[0012] In another preferred embodiment, the two ends of each lever are arranged on each lateral side of a thrust area of ​​the lever from which the vertically directed pressure force on the vehicle rolling means is generated during the operation of the displacement motor, thereby achieving controlled displacement of the vehicle rolling means.

[0013] In another preferred embodiment, a first end of each lever arm is coupled to a first rotatable device within the upper portion of the vehicle body, such as a rotatable bolt, thereby defining a lever arm pivot point, and a second end of each lever arm is at least indirectly coupled to the displacement motor, allowing rotation of the lever arm about its pivot point at the first end. This rotation causes the desired vertical displacement of the vehicle rolling means.

[0014] In another preferred embodiment, the displacement arrangement further comprises at least one locking means, for example an elongated hook, each locking means being pivotally connected to its corresponding lever at or near the other end, and a second rotatable device located at the upper half of the vehicle body, the locking means and the second rotatable device being interconnected to allow releasable blocking after a predetermined angular rotation performed by the displacement motor.

[0015] In another preferred embodiment, at least one of the locking means / means is connected to a rotor on the displacement motor which forces a rotational movement on the connected locking means, thereby causing the desired vertical displacement of the at least one of the first set of vehicle rolling means and the second set of vehicle rolling means, relative to any underlying storage system.

[0016] In another preferred embodiment, the vehicle assembly further comprises at least one drive motor located at the lateral plane above the cavity, the drive motor being arranged to drive at least one of the first set of vehicle rolling means and the second set of vehicle means along the lateral plane of any underlying storage system set up by the first (X) and second (Y) directions. The change in direction of the vehicle assembly is preferably discrete, i.e. it constitutes a 90 degree turn.

[0017] In another preferred embodiment, at least one of the vehicle rolling means comprises a first part and a second part arranged on opposite side walls of the vehicle body and a vertically displaceable rod rigidly connecting the first part and the second part at a lateral plane above the cavity, at least one of the first and second parts further comprising an upper rotation unit and a lower rotation unit, the upper and lower rotation units being connected to enable simultaneous rotation of the units. At least one of the upper and lower rotation units may be wheels, belts, etc. Furthermore, the string / cord may comprise any elongated object which allows said simultaneous rotation. The lower rotation unit is configured to at least indirectly contact the underlying storage system in use. The lower rotation unit may advantageously comprise two laterally spaced wheels which are configured to cause releasable contact with the underlying storage system in use, i.e.when the vehicle assembly is set to a non-displaced state.

[0018] In one embodiment, the connecting string surrounds both the lower and upper rotation units.

[0019] In an alternative embodiment, the connecting string surrounds the upper rotation unit, which is arranged on the outside of the lower rotation unit. The latter configuration can be achieved by means of additional wheels around which the string is laid. The assembly of the string and the additional wheels should then be configured to form a stable pressure on the lower rotation unit, for example by using two smaller wheels arranged adjacent each of the wheels of the lower rotation unit, and where the string is guided between the larger wheels and the additional wheels. This embodiment is considered to be more advantageous since it ensures a better contact between the lower rotation unit and the underlying storage system in use. The invention also relates to a storage system suitable for storing containers. The storage system comprises a remotely controlled vehicle assembly according to any of the configurations described above, a vehicle support and a container storage structure supporting the vehicle support.The structure comprises multiple storage columns, each storage column being arranged to house a vertical stack of storage containers.

[0020] The invention also relates to a method suitable for changing the direction of a remotely controlled vehicle assembly when operating on a storage system. The vehicle assembly comprises a vehicle body having a cavity for receiving a storage container within the storage system, a vehicle hoist coupled at least indirectly to the vehicle body which is suitable for hoisting the storage container into the cavity, a displacement arrangement comprising a displacement motor and drive means comprising a first set of vehicle rolling means coupled to the vehicle body which permits movement of the vehicle along a first direction (X) in the storage system in use and a second set of vehicle rolling means coupled to the vehicle body which permits movement of the vehicle along a second direction (Y) in the storage system in use, the second direction (Y) being perpendicular to the first direction (X).The method is characterized by the following steps: - rotating at least one lever by operating the displacement motor, the displacement motor being located near the upper lateral plane of, or above, the cavity and - vertically displacing one of the first set of vehicle rolling means and the second set of vehicle rolling means by exerting a compressive force on the vehicle rolling means in a vertical direction, away from any underlying storage system, by means of a rotating lever.

[0021] In a preferred embodiment, the remotely controlled vehicle assembly in the described method is a vehicle according to any of the configurations described above.

[0022] In the following description, several specific details are given to provide a thorough understanding of the embodiments of the claimed vehicle system and method. However, those skilled in the relevant art will understand that these embodiments may be practiced without one or more of the specific details, or with other components, systems, etc. In other instances, well-known structures or operations are not shown or are not described in detail to avoid obscuring aspects of the disclosed embodiments. Brief description of the drawings:

[0023] Fig. 1 is a perspective view of a prior art storage system; Fig. 2 is a perspective view from below of a remotely operated vehicle according to one embodiment of the invention; Fig. 3 is a perspective view from above of a remotely operated vehicle according to one embodiment of the invention; Fig. 4 is a side perspective view of a portion of a storage system according to one embodiment of the invention that includes a container storage grid, a vehicle support and a robot; Fig. 5 (a) and (b) are side perspective views at two different angles of a remotely operated vehicle according to one embodiment of the invention, where the outer side walls and the top cover have been removed; Fig. 6 (a) and (b) are side perspective views of a remotely operated vehicle according to one embodiment of the invention, where one of its wheel sets is in the operational (lowered) position and in the non-operational (raised) position, respectively; Fig.7 (a) and (b) are transparent cross-sectional views of the remote-controlled vehicle of Fig. 6, with one of its wheel sets in the operational position and the non-operational position, respectively; Fig. 8 (a) and (b) are views of the remote-controlled vehicle of Fig. 6 seen from the bottom and top, respectively; and Fig. 9 shows a schematic diagram of the wheel configuration of a side wall of the remote-controlled vehicle of Fig. 6. Detailed description of the invention:

[0024] Hereinafter, all relative terms used to describe the inventive robot such as upper, lower, lateral, vertical, X-direction, Y-direction, Z-direction, etc., shall be interpreted using the above-described known storage system as the reference system. Figs. 2 and 3 show perspective views at two different angles of a robot 1 comprising a rectangular vehicle body or framework 4, which in turn shows a cavity 7 centrally disposed therein, a top cover 72 covering the top portion of the body 4, a first set of four wheels 10 mounted on the inside of the cavity 7 and a second set of four wheels 11 mounted on the outer walls of the body 4. The first and second wheel sets 10,11 are oriented perpendicular to each other. For the sake of understanding, a Cartesian coordinate system is shown with its X, Y and Z axes aligned along the principal directions of the rectangular vehicle body 4.The size of the cavity 7 is adapted to accommodate at least the largest storage container 2 intended to be picked up by the robot 1, and preferably also a vehicle lift device 9 (Fig. 4). Fig. 4 shows a part of a storage system 3 where the robot 1 is in a lifting position on a vehicle support 14, directly above a storage column 8 within a supporting container storage structure 15. A vehicle lift device 9 is lowered a distance into the storage column 8 to hook onto, and lift up, any storage container 2 within the column 8. Fig. 5 (a) and (b) show the inventive robot 1 where the side walls and top cover 72 have been removed to better show all relevant components constituting a wheel displacement arrangement 23-28 and the drive means 10,11. A Cartesian coordinate system (X,Y,Z) has been inserted to enhance understanding.As in the embodiment shown in Figures 2 and 3, the drive means 10,11 comprise a first set of vehicle rolling means 10 and a second set of vehicle rolling means 11 which are configured to move the robot 1 along the top of a storage system 3 in the X and Y directions, respectively. Each set 10,11 is composed of two parts 10a, 10b which are arranged along opposing side walls of the framework 4. Each of these parts 10a, 10b further comprises a main wheel 30 arranged at the upper part 4u of the framework and two slave wheels 31a, 31b arranged at, or near, each of the two corners of the corresponding lower edges. The slave wheels 31a, 31b constitute the conventional drive wheels which contact, or near to contact, the underlying storage system 3 in use. The three wheels 30, 31a, 31b of each of the four parts, which are interconnected by an at least partially surrounding belt or string 32, ensure a simultaneous rotation of each slave wheel 31a, 31b when the main wheel 30 is put into operation.

[0025] To lift the slave wheels 31a, 31b from the storage system 3 during a change of direction of the robot 1, a vertically displaceable rod 22 located above the cavity 7 couples together two surfaces or plates 34a, 34b arranged along opposing side walls of the framework 4. Each plate rigidly couples together the main wheel 30, the slave wheels 31 and the belt 32 within the relevant set of vehicle rolling means 10. Any displacement of the rod 22 thus results in a rigid displacement of the coupled driving means 10, 11.

[0026] The displacement of the rod 22 can be achieved by means of a lever 23 configured to exert an upward pressure force, thereby pushing the rod 22 vertically. To ensure high predictability during the displacement, the rod 22 can be guided by suitable slots 33 having a width that is somewhat larger than the diameter of the rod 22 and a length that is somewhat longer than the total displacement length (Az) (Figure

[0027] 6). The end of the lever arm 23 is mounted on a rotatable bolt 26 located at one lateral side of the rod 22, thereby defining a pivot point. The lateral distance from the rod 22 may, for example, be half the length of the lever arm 23.

[0028] In a preferred embodiment, the rotation mechanism of the lever 23 is located at the opposite lateral side of the rod 22. This particular embodiment is shown in Figures 5-8. Referring to Figures 5 and 6, the rotation mechanism comprises a displacement motor 25 (e.g., a DC motor) having a rotor 25a, a lever wheel 28 connected to the rotor 25a, a locking arm 27 connected to one end of the lever wheel 28 and the other end to the end of the lever arm 23 opposite the rotatable bolt 26. The locking arm 27 is configured to at least partially surround the lever wheel 28 when the lever arm 23 has been rotated into its upper position, thereby blocking any vertical movement of the lever arm 23 that is not caused by controlled operation of the displacement motor 25. Figures 6 (b) and 7 (b) show the situation where the locking arm 27 is in its upper position, a position that effectively blocks any purely translatory movement of the drive means 10.

[0029] In an alternative embodiment, the rotation of the lever 23 may be driven by a displacement motor arranged at its pivot point 26.

[0030] In yet another alternative embodiment, the rotation of the lever 23 can be driven by arranging a suitable displacement motor both at its pivot point 26 and at or near the opposite end of the lever 23. Figures 6, 7 (a) and figures 6, 7 (b) show the robot 1 with its main and slave wheels 30, 31 in their non-displaced and displaced states, respectively. In the figures, Az denotes the displacement length of the drive means 10, 11 after a successful wheel displacement. The dotted lines are added to better indicate the actual wheel positions, where the upper pair of lines shows the change in position of the main wheel 20, and the two lower pairs of lines show the change in position of the two slave wheels 31a, 31b. Figures 8 (a) and (b) show the peeled-off robot 1 from above and below, respectively. The aforementioned displacement motor 25 with its rotor 25a is shown on the lower left side.The drive motors 20,21 for driving the robot in the X and Y directions are shown at the upper left and lower right sides, respectively, and the vehicle hoist motor 9a is shown at the upper right side. At least one of the motors is preferably a DC motor. Each drive motor 20,21 drives a drive shaft 35,36 which is coupled at its end to the opposing main wheel 30, thereby allowing the exchange of motor-induced rotational force to the slave wheels 31a,31b via the main wheel 30.

[0031] In Figures 5-7, the belt 32 connecting the main wheel 30 with the slave wheels 31a,31b is shown to completely enclose all the wheels 30,31. This configuration is easy to implement and is cost-effective. Since the belt 32 is located between the rotation point of the slave wheels 31a,31b and the underlying storage system 3, the downward force can be weakened. In Figure 9, therefore, an alternative embodiment is proposed in which one or more smaller additional wheels 37, for example two additional wheels, are arranged adjacent to at least some, preferably all, of the slave wheels 31a,31b, and in which the belt 32 is guided between the slave wheel 31a,31b and its additional wheel 37. This alternative embodiment ensures a desired increase in the downward contact force between the slave wheels 31a,31b and the underlying storage system 3.

[0032] All operations of the robot 1 are controlled by wireless communication means 19 and remote control units. This includes control of robot movements, the vehicle lifting device 9 and any measurement of vehicle position.

[0033] In the foregoing description, various aspects of the assembly of the invention have been described with reference to the illustrative embodiments. However, for the purpose of explanation, specific figures, systems and configurations have been set forth to provide a thorough understanding of the apparatus and its functions. However, it is not intended that this description be construed in a limiting manner. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the apparatus which are apparent to those skilled in the art to which the subject matter relates, are intended to be within the scope of the present invention. List of reference numbers / letters: 1 Remote controlled vehicle assembly 2 Storage container 3 Storage system 4 Vehicle body / framework 4u Upper half of vehicle body 7 Cavity 8 Storage column 9 Vehicle lift device 9a Vehicle lift motor

[0034] 10 First set of vehicle rolling stock / first set of wheels / propulsion 10a First part of vehicle rolling stock 10b Second part of vehicle rolling stock 11 Second set of vehicle rolling stock / second set of wheels / propulsion 13 Supporting rail 14 Vehicle support 15 Container storage structure / container storage grid

[0035] 19 Circuit board / management system / battery management system 20 Drive motor to drive vehicle in X direction 21 Drive motor to drive vehicle in Y direction 22 Vertically movable rod 23 Lever

[0036] 23a First longitudinal end of the lever arm 23b Second longitudinal end of the lever arm 24 Impact area / stop area 25 Displacement motor 25a Rotor for displacement motor

[0037] 26 First rotatable device / rotatable bolt / pivot point 27 Locking device / locking arm 28 Other rotating device / lever wheel 30 Upper rotation unit / Main wheel 31 Lower rotation unit / Slave wheel

[0038] 3 la Laterally spaced wheel (of lower rotation unit) / first slave wheel 32b Laterally spaced wheel (of lower rotation unit) / second slave wheel 32 String / rope / belt 33 Columns 34a First plate 34b Second plate 35 Drive shaft, X direction 36 Drive shaft, Y direction 37 Additional wheels 50 Container lifting device 60 Receiving station / port 72 Top cover 73 Surrounding cover 74 Handle

[0039] 75 Wireless communication means / control panel Az Offset length

Claims

1. A remotely controlled vehicle assembly (1) for picking up storage containers (2) from a storage system (3), comprising- a vehicle body (4) presenting a cavity (7) for receiving a storage container (2) stored within the storage system (3),- a vehicle hoist (9,9a) coupled to the vehicle body (4) for lifting the storage container (2) into the cavity (7),- drive means comprising- a first set of vehicle rolling means (10) coupled to the vehicle body (4) and permitting movement of the vehicle (1) along a first direction (X) in the storage system during use and- a second set of vehicle rolling means (11) coupled to the vehicle body (4) and permitting movement of the vehicle (1) along a second direction (Y) in the storage system (3) during use, wherein the second direction (Y) is perpendicular to the first direction (X),- a displacement arrangement (23-28) coupled to a drive means comprising a displacement motor (25) configured to generate force to displace at least one (10) of a first set of vehicle rolling means (10) and a second set of vehicle rolling means (11) between a displaced state where the vehicle rolling means (10,11) are displaced away from the underlying storage system (3) during use, and a non-displaced state where the vehicle rolling means (10,11) are in contact with the underlying storage system (3) during use, characterized in that the displacement motor (25) is located in a lateral plane above the cavity (7), and further configured to generate a force that is converted into a vertically directed pressure force acting on the first or second set of vehicle rolling means (10,11)., 2. The vehicle assembly (1) according to claim 1, characterized in that the power transmission from the displacement motor (25) to the corresponding vehicle rolling means (10, 11) is carried out by means of at least one lever (23) configured to allow mechanical switching between the displaced state and the non-displaced state.

3. The vehicle assembly (1) according to claim 1 or 2, characterized in that at least one of the vehicle rolling means (10,11) comprises a first part (10a) and a second part (10b) arranged at opposite side walls of the vehicle body (4), and a vertically displaceable rod (22) rigidly connecting the first part (10a) and the second part (10b) across the cavity (7).

4. The vehicle assembly (1) according to claim 3, characterized in that the displacement arrangement (23-28) comprises at least one lever (23) configured to abut against the vertically displaceable rod (22) upon operation of the displacement motor (25).

5. The vehicle assembly (1) according to claim 4, characterized in that the at least one lever (23) is arranged at least partially below the vertically displaceable rod (22).

6. The vehicle assembly (1) according to claim 4 or 5, characterized in that the at least one lever (23) is located at an upper half (4u) of the vehicle body (4).

7. The vehicle assembly (1) according to any one of the preceding claims, characterized in that the displacement arrangement (23-28) comprises at least one lever (23) connected to at least one (10) of the first and second sets of vehicle rolling means (10,11), the two ends (23a,23b) of each lever (23) being arranged on each lateral side of a stop area (24) of the lever (23) from which the vertically directed pressure force on the vehicle rolling means (10,11) is generated during operation of the displacement motor (25).

8. The vehicle assembly (1) according to claim 7, characterized in that a first end (23a) of each lever (23) is connected to a first rotatable device (26) arranged inside an upper part (4u) of the vehicle body (4), and a second end (23b) of each lever (23) is connected to the displacement motor (25), which allows rotation of the lever (23) about its pivot point at the first end (23a), thereby causing a vertical displacement of the vehicle rolling means (10,11).

9. The vehicle assembly (1) according to claim 8, characterized in that the displacement arrangement (23-28) further comprises at least one locking means (27), each locking means (27) being pivotally connected to its corresponding lever (23) at or near the other end (23b) and a second rotatable device (28) located at the upper half (4u) of the vehicle body (4), the locking means (27) and the second rotatable device being coupled together to allow releasable blocking after a predetermined angular rotation.

10. The vehicle assembly (1) according to claim 9, characterized in that at least one of the locking means / locking means (27) is connected to a rotor (25a) of the displacement motor (25).

11. The vehicle assembly (1) according to any one of the preceding claims, characterized in that the vehicle assembly further comprises at least one drive motor (20,21) located at the lateral plane above the cavity (7), the drive motor (20,21) being arranged to drive at least one of the first set of vehicle rolling means (10) and the second set of vehicle rolling means (11) along the lateral plane of any underlying storage system (3).

12. The vehicle assembly (1) according to any one of the preceding claims, characterized in that at least one of the vehicle rolling means (10,11) comprises a first part (10a) and a second part (10b) arranged at opposite side walls of the vehicle body (4), and a vertically displaceable rod (22) rigidly connecting the first part (10a) and the second part (10b) in a lateral plane above the cavity (7), wherein at least one of the first and second parts (10a, 10b) further comprises an upper rotation unit (30) and a lower rotation unit (31), the upper and lower rotation units (30,31) being connected by a string (32), which enables simultaneous rotation of the units (30,31).

13. The vehicle assembly (1) according to claim 12, characterized in that the lower rotation unit (31) comprises two laterally spaced wheels (31a, 31b), which wheels (31a, 31b) are configured to provide releasable contact with the underlying storage system (3) in use.

14. The vehicle assembly (1) according to claim 12 or 13, characterized in that the connecting string (832) surrounds the lower rotation unit (31).

15. The vehicle assembly (1) according to claim 12 or 13, characterized in that the connecting string (832) is arranged outside the lower rotation unit (31).

16. A storage system (3) for storing containers (2), characterized in that it comprises- a remotely controlled vehicle assembly (1) according to any one of claims 1-15,- a vehicle support (14) and- a container storage structure (15) supporting the vehicle support (14), the structure (15) comprising a plurality of storage columns (8,8a,8b), each storage column (8,8a,8b) being arranged to accommodate a vertical stack of storage containers (2).

17. A method for changing the direction of a remotely operated vehicle assembly (1) when operating on a storage system (3), the vehicle assembly (1) comprising a vehicle body (4) presenting a cavity (7) for receiving a storage container (2) within the storage system (3), a vehicle hoist (9,9a) coupled to the vehicle body (4) for hoisting the storage container (2) into the cavity (7), a displacement arrangement (23,23a,23b,24,25,26) comprising a displacement motor (25) and a drive means comprising a first set of vehicle rolling means (10) coupled to the vehicle body (4) allowing movement of the vehicle (1) along a first direction (X) within the storage system (3) in use and a second set of vehicle rolling means (11) coupled to the vehicle body (4) allowing movement of the vehicle (1) along a second direction (Y) within the storage system (3) in use. using the second direction (Y) being perpendicular to the first direction (X),characterized by the following steps:- rotating at least one lever (23) by operating the displacement motor (25), the displacement motor (25) being located in a lateral plane above the cavity (7) and- vertically displacing one of the first set of vehicle rolling means (10) and the second set of vehicle rolling means (11) by exerting a compressive force on the vehicle rolling means (10,11) in a vertical direction, away from any underlying storage system (3), by means of the rotating lever (23)., 18. The method according to claim 17, characterized in that the remote controlled vehicle assembly (1) is according to any one of claims 2-15.