MECANUM-WHEELED VEHICLE AND OPERATING METHOD

Abstract

A mecanum-wheeled vehicle (1), in particular for transporting a load, comprising a chassis (5) extending along a longitudinal axis (L) and a width axis (B) oriented perpendicular to the same, said chassis comprising at least four mecanum wheel drives (2; 2a to 2d) which can be controlled via control means (13) for carrying out an omnidirectional operation of the mecanum-wheeled vehicle (1), wherein the chassis (5) has a first chassis section (21a) with at least two (2a, 2b) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) and a second chassis section (21b) with at least two (2c, 2d) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d). According to the invention, the first and the second chassis sections (21a, 21b) are arranged adjacent along a first adjustment axis (E1) and are mechanically connected to one another such that the spacing between same can be varied, and the spacing between the first and second chassis sections (21a, 21b) is adjustable along a first adjustment axis (E1) by controlling at least one of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) of the first chassis section (21a) and/or of the second chassis section (21b) by means of the control means (13).

Claims

1. Mecanum-wheeled vehicle (1) for transporting a load, comprising a chassis (5) extending along a longitudinal axis (L) and a width axis (B) oriented perpendicular to the same, said chassis comprising at least four mecanum wheel drives (2; 2a to 2d) which can be controlled via control means (13) for carrying out an omnidirectional operation of the mecanum-wheeled vehicle (1), wherein the chassis (5) has a first chassis section (21a) with at least two (2a, 2b) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) and a second chassis section (21b) with at least two (2c, 2d) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d), wherein the first and the second chassis sections (21a, 21b) are arranged adjacent along a first adjustment axis (E1) and are mechanically connected to one another such that the spacing between the same can be varied, and the spacing between the first and second chassis sections (21a, 21b) is adjustable along a first adjustment axis (E1) by controlling at least one of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) of the first chassis section (21a) and/or of the second chassis section (21b) by means of the control means (13).

2. Mecanum-wheeled vehicle according to claim 1, wherein the chassis (5) comprises a third chassis section (21c) with at least two (2a, 2b) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) and a fourth chassis section (21 d) with at least two (2b, 2d) of the mecanum wheel drives (2; 2a, 2b, 2c, 2d), wherein the third and the fourth chassis sections (21c, 21d) are mechanically connected to one another such that the spacing between same can be varied, and wherein the spacing between the third and fourth chassis sections (21c, 21d) is adjustable along a second adjustment axis (E2) extending angularly, especially perpendicular, to the first adjustment axis (E1), by controlling at least one of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) of the third and/or fourth chassis sections (21c, 21 d) by means of the control means (13).

3. Mecanum-wheeled vehicle according to claim 2, wherein the third and the fourth chassis sections (21c, 21 d) each comprise one subsection (22a to 22d) of the first chassis section (21a) which has at least one mecanum wheel drive (2; 2a, 2b, 2c, 2d), and one subsection (22; 22a, 22b, 22c, 22d) of the second chassis section (21b) which has at least one mecanum wheel drive (2; 2a, 2b, 2c, 2d) and is adjacent to the first adjustment axis (E1), or respectively are formed by the said, and that the at least two mecanum wheel drives (2a, 2c) of the third chassis section (21c) comprise at least one mecanum wheel drive (2a) of the first chassis section (21c) and at least one mecanum wheel drive (2c) of the second chassis section (21b) or are formed by the said, and that the at least two mecanum wheel drives (2b, 2d) of the fourth chassis section (21 d) comprise at least one mecanum wheel drive (2b) of the first chassis section (21a) and at least one mecanum wheel drive (2d) of the second chassis section (21b) or are formed by the said.

4. Mecanum-wheeled vehicle according to claim 3, wherein the third and the fourth chassis section (21c, 21d) are directly connected to one another such that the spacing between same can be varied, or using a connecting-chassis-section (23) only via the subsections (22a, 22b) of the first chassis section (21a) or alternatively (22c, 22d) of the second chassis section (21b) or wherein the third and the fourth chassis section (21c, 21 d) are directly connected to one another such that the spacing between same can be varied, or using a connecting-chassis-section (23) both via the subsections (22a, 22b; 22c, 22d) of the first chassis section (21a) and of the second chassis section (21b).

5. Mecanum-wheeled vehicle according to claim 1, wherein the first adjustment axis (E1) coincides with the width axis (B) or the longitudinal axis (L).

6. Mecanum-wheeled vehicle according to claim 1, wherein the mecanum wheel drives (2a to 2d) each comprise at least one, specifically electromotive, drive motor, and at least one mecanum wheel (3), drivable by the said, which is rotatable about a mecanum wheel rotational axis (20) and carries, on the outer circumference, a plurality of rollers which are adjacent in circumferential direction around the mecanum wheel rotational axis (20), wherein the mecanum wheel rotational axes (20) of the mecanum wheels (3) are orientated in parallel to the width axis (B) and perpendicular relative to the longitudinal axis (L).

7. Mecanum-wheeled vehicle according to claim 1, wherein the mecanum-wheeled vehicle (1) comprises lifting means (15) for varying a height-spacing orientated perpendicular relative to the longitudinal axis (L) and to the width axis (B) between a resting surface (17), which is formed by a lifting fork (16) for a payload, and the mecanum wheel drives (2; 2a, 2b, 2c, 2d).

8. Mecanum-wheeled vehicle according to claim 7, wherein the resting surface (17), specifically the lifting fork (16), is arranged between the first and the second chassis section (21a, 21b), and the spacing of the first and/or second chassis sections (21a, 21b) and the resting surface (17) along the first adjustment axis (E1) is adjustable by controlling the mecanum wheel drives (2; 2a, 2b, 2c, 2d) of the first and/or second chassis sections (21a, 21b).

9. Mecanum-wheeled vehicle according to claim 1, wherein a weight force of the chassis (5) is supportable both via the mecanum wheels (3) and, as well, via support means (6) of the mecanum-wheeled vehicle (1) provided in addition to the mecanum wheels (3) on a ground (U), and wherein the mecanum wheel drives (2; 2a, 2b, 2c, 2d) having at least one mecanum wheel (3) each, for limiting the weight force fraction of the chassis (5), and an optional load to be carried by the said, to be supported via the mecanum wheel drives (2; 2a, 2b, 2c, 2d) on the ground (U) are mounted by means of energy storage means (4) resiliently/springy against the chassis (5).

10. Mecanum-wheeled vehicle according to claim 9, wherein the support means (6) comprise at least one load wheel, which during travel of the mecanum-wheeled vehicle (1) is rotatable about a rotational axis (7), and which, during change of direction of the mecanum-wheeled vehicle (1), is rotatable about an articulated axis (8), and/or wherein the support means (6) comprise a ball, which is arranged rotatable, for support on the ground (U).

11. Mecanum-wheeled vehicle according to claim 9, wherein the energy storage means (4) are formed such that the support means (6) are disposed, in the event of the chassis (5) not being charged by a payload, above a support face defined by the mecanum wheels (3), and lower themselves when a load is applied, concomitantly with an increase in the spring tensioning of the energy storage means (4) together with the chassis (5).

12. Mecanum-wheeled vehicle according to claim 11, wherein the spacing between a support face (9) formed be the support means (6) and the support face defined by the mecanum wheels (3) is adjustable.

13. Mecanum-wheeled vehicle according to claim 9, wherein the support means (6) are not springy mounted against the chassis (5) or are springy mounted against the chassis (5) via support energy storage means such that a spring stiffness of the support energy storage means is larger than a spring stiffness of the energy storage means (4).

14. Mecanum-wheeled vehicle according to claim 9, wherein a pre-tensioning of the energy storage means (4) and/or a spring path of the energy storage means (4) for adjusting the weight fraction maximally to be supported by the mecanum wheels (3) on the ground (U) can be adjusted manually or by using actuator means.

15. Mecanum-wheeled vehicle according to claim 9, wherein the mecanum-wheeled vehicle (1) comprises measuring devices for determining a weight force or a weight force fraction of the chassis (5) and/or a payload, and wherein the measuring devices are connected in a signal-transmitting way with control means (13) for controlling the actuator means for adjusting the pre-tensioning of the energy storage means (4) and/or the spring path as a function of a sensor signal of the measuring devices.

16. Mecanum-wheeled vehicle according to claim 1, wherein the first chassis section (21a) and the second chassis section (21b), can be adjusted along the first adjustment axis (E1), without a change of a height of the mecanum-wheeled vehicle (1), as measured perpendicular to the longitudinal axis (L) and to the width axis (B), resulting therefrom.

17. Method for operating a mecanum-wheeled vehicle (1) according to claim 1, wherein the spacing between the first and second chassis sections (21a and 21b) along a first adjustment axis (E1) is adjusted by controlling of at least one of the mecanum wheel drives (2; 2a, 2b, 2c, 2d) of the first chassis section (21a) and/or the second chassis section (21b) by means of the control means (13).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Further advantages, features and details of the invention can be learned from the following description of preferred exemplary embodiments as well as from the drawings.

[0046] The said drawings depict, in

[0047] FIG. 1a-1d: a mecanum-wheeled vehicle constructed in accordance to the concept of the invention, viewed from below, in different operating states, or having different spacings from chassis sections arranged adjacent to one another, respectively,

[0048] FIG. 2: in a schematic view, a mecanum-wheeled vehicle constructed according to the concept of the invention, in a plan view, during different operating states,

[0049] FIGS. 3 and 4: an alternative embodiment of a mecanum-wheeled vehicle constructed according to the concept of the invention having lifting means comprising a lifting fork extending perpendicularly to a first adjusting axis, and arranged in a region between a first and a second vehicle section, which are variable in spacing along the adjustment axis,

[0050] FIG. 5: a further alternative embodiment of a mecanum-wheeled vehicle formed according to the concept of the invention comprising lifting means,

[0051] FIG. 6a: a possible embodiment of a mecanum-wheeled vehicle formed according to the concept of the invention in a side view without payload,

[0052] FIG. 6b: a mecanum-wheeled vehicle according to FIG. 6a including a payload,

[0053] FIG. 7: a possible embodiment of a mecanum-wheeled vehicle constructed according to the concept of the invention, in the view from below,

[0054] FIG. 8: a side view of an alternative embodiment of a mecanum-wheeled vehicle constructed according to the concept of the invention,

[0055] FIG. 9: a further alternative embodiment of a mecanum-wheeled vehicle constructed according to the concept of the invention, having integral lifting means, and

[0056] FIG. 10: a side view of another alternative embodiment of a mecanum-wheeled vehicle constructed according to the concept of the invention.

[0057] In the figures, like elements and elements having the same function are identified by the same reference symbols.

DETAILED DESCRIPTION

[0058] A mecanum-wheeled vehicle 1 is shown in FIGS. 1a to 1d. The same comprises a total of four mecanum wheel drives 2a to 2d, which delimit the corners of an imaginary rectangle. Each mecanum wheel drive 2a to 2d comprises a mecanum wheel 3a to 3d each having an electromotive drive 12a to 12d. All of the mecanum wheel drives 2a to 2d, more specifically the electromotive drives 12a to 12d thereof, are connected to control means (not shown) for individually driving the mecanum wheels 3a to 3d to ensure an omnidirectional operation.

[0059] The mecanum wheel drives 2a to 2d are connected to a chassis 5 in a fixed manner, in particular by means of energy storage means to be explained later. In addition to the mecanum wheel drives 2a to 2d, the chassis 5 carries support means 6 which are firmly connected with these, here in the form of load wheels which are rotatably mounted about a respective rotational axis 7 as well as an articulated axis 8 oriented perpendicular thereto. The support means 6 can neither be driven directly about the rotary axis 7 nor about the articulation axis 8 by a separate drive, but by rotating or pivoting about them as a function of a locomotion of the mecanum-wheeled vehicle 1 due to the drive of the mecanum wheels 3a to 3b.

[0060] The mecanum-wheeled vehicle 1 or the chassis 5, respectively, comprises a longitudinal axis L as well as a width axis B oriented perpendicularly thereto, the longitudinal axis L being oriented perpendicularly to mecanum wheel rotational axes 20 around which the rims of the mecanum wheels are rotatable. In an angle to these mecanum wheel rotational axes 20 and/or rim rotational axes, there are oriented roller rotational axles about which rollers can roll off, which are held by the mecanum wheel rims at the outer circumference in a manner known per se.

[0061] The chassis 5 has a first chassis section 21a including the mecanum wheel drives 2a and 2b and a second chassis section 21b including the mecanum wheel drives 2b and 2c. These two chassis sections 21a and 21b are variable in spacing along a first adjustment axis E1, which herein extends, for example, along the width extension or in parallel to the width axis B. For this purpose, the first and second chassis sections 21a, 21b are connected to one another mechanically, and in a manner variable in spacing, along the adjustment axis E1, for example by a non-shown telescopic or rail connection which is arranged on the left and extends from the top downwards in the drawing plane.

[0062] In order to vary the mecanum-wheeled vehicle width, i.e. the extension of the chassis 5 along the width axis B, the mecanum wheel drives 2c and 2d, as shown in FIG. 1b, can, for example, be rotated in opposite senses. Preferably, the mecanum wheel drives 2a and 2b are simultaneously braked or held tight. In any event, the mecanum wheel drives 2a to 2d are controlled in such a way that a force component acts on the chassis sections 21a and 21b along the first adjustment axis E1 such that the chassis sections 21a and 21b move relative to one another along the first adjustment axis E1. As shown in FIG. 1c, simultaneously or timely delayed, the mecanum wheel drives 2a to 2b can be rotated in opposite senses for a further widening, while the mecanum wheel drives 2d are, for example, braked. The adjusting movements resulting from FIGS. 1b and 1c can, in principle, also be carried out simultaneously. In any case, it is essential that the first and second chassis sections 21a and 21b are adjusted relative to each other along the adjustment axis E1 by a corresponding control of the mecanum wheel drives 2a to 2d, while maintaining a mechanical connection variable in spacing.

[0063] In particular from FIG. 1d, it can be seen that the chassis 5, in addition to the first and second chassis sections 21a and 21b, includes a third chassis section 21c and a fourth chassis section 21d. The third chassis section 21c comprises the mecanum wheel drive 2a and the mecanum wheel drive 2c, while the fourth chassis section 21d comprises the mecanum wheel drives 2b and 2d. The spacing inbetween the chassis sections 21c and 21d can be varied by a corresponding control of the mecanum wheel drives 2a to 2d, for example by braking or holding the mecanum wheel drives 2a and 2c locked, and simultaneously rotating the mecanum wheel drives 2b and 2d in a common rotational direction, along the second adjustment axis E2 which is running perpendicular to the first adjustment axis E1, while maintaining the distance-variable mechanical connection of the third and fourth chassis sections 21c and 21d along the adjustment axis E2.

[0064] An embodiment in which the vehicle can only be adjusted along one of the adjustment axes E1 or E2 is also basically feasible. In the case of the longitudinal adjustability, then, the adjustment axis designated by E2 is the first adjustment axis E1, and the chassis sections 21c and 21d are the first and second chassis sections 21a and 21b, respectively.

[0065] In the specific exemplary embodiment, the chassis sections 21a to 21d each consist of pairwise combinations of partial chassis sections (subsections) 22a to 22d of the chassis 5. Specifically, the first chassis section 21a is formed by the subsections 22a and 22b each carrying one mecanum wheel drive 2a or 2b, while the second chassis section 21b is formed by the subsections 22c and 22d having the mecanum wheel drives 2c and 2d, herein for achieving the width adjustability. For achieving length adjustability, the third chassis section 21c is formed by the subsections 22a and 22c having their mecanum wheel drives 2a and 2c, and the fourth chassis section 21d is formed by the subsections 22b and 22d having their mecanum wheel drives 2b and 2d.

[0066] In FIG. 2, a mecanum-wheeled vehicle 1 which in the drawing plane on the left is shown in its minimum area extension, in which the chassis sections 21a to 21d or subsections 22a to 22d are minimally spaced, while in the drawing plane on the right, the chassis is enlarged in width, as well as in length, wherein, as explained repeatedly, basically, also an embodiment can be implemented which is exclusively variable in width or length.

[0067] In the FIGS. 3 and 4, a particularly preferred embodiment of a mecanum-wheeled vehicle 1 is shown in the form of a load transport vehicle. Just by way of example, the illustrated mecanum-wheeled vehicle 1 is variable in spacing only along the first adjustment axis E1, wherein the adjustment axis E1, here, again coincides with the width axis B of the vehicle. The mecanum-wheeled vehicle 1 comprises a first chassis section 21a and a second chassis section 21b with their mecanum wheel drives 2a and 2b, or 2c and 2d, respectively, arranged one behind the other, perpendicular to the adjustment axis E1. The two chassis sections 21a and 21b are slidably connected along the adjustment axis E1 to a connecting chassis section 23. In other words, the chassis sections 21a and 21d are slidably connected directly to the said connecting chassis section 23 and, thereby, are indirectly mechanically connected to one another such that the spacing between same can be varied. The spacing between the chassis sections 21a and 21b along the first adjustment axis E1 can be adjusted by a corresponding control of the mecanum wheel drives 2a to 2d, namely between the maximum spacing shown in FIG. 3a and the minimum spacing shown in FIG. 3b. In all relative positions, the mechanical connection of the chassis sections 21a and 21b is maintained.

[0068] It can be seen that lifting means 15 comprising a lifting fork 16 are arranged on the connecting chassis section 23. The lifting fork 16 defines or forms a resting surface 17 for a payload 10. The lifting fork 16 is located in a region between the first chassis sections 21a and 21b and extends perpendicular to the first adjustment axis E1.

[0069] The above design allows the chassis to be minimized to its minimum width after accommodating the payload 10 (pallet) by corresponding control of the mecanum wheel drives 2a to 2d, whereby the mobility is increased.

[0070] If required, the mecanum-wheeled vehicle 1 shown in FIGS. 3 and 4 which is only variable in width, can additionally be designed variable in length, and then a third and a fourth chassis section 21c and 21d are to be provided with two mecanum wheel drives 2c and 2d, each. Therein, preferably, as mecanum wheel drives 2a to 2d the same mecanum wheel drives are used as they are provided for achieving the width adjustability, analogously to the exemplary embodiment according to FIGS. 1a to 1d.

[0071] A mecanum-wheeled vehicle 1 is shown in FIG. 5. The design substantially corresponds to the construction of the mecanum-wheeled vehicle 1 according to FIGS. 3 and 4, but, additionally, the mecanum-wheeled vehicle 1 according to FIG. 4 has an extension variability along a second adjustment axis E2. For this purpose, in addition to the first and second chassis sections 21a and 21b, a third and a fourth chassis section 21c and 21d are provided. The two chassis sections 21a and 21b are mechanically connected to one another indirectly via the connecting chassis section 23 such that the spacing between same can be varied. The said is located in a region between the, and optionally above or below the, subsections 22b and 22d. The subsection 22d, otherwise, along the second adjustment axis E2 is only connected with the subsection 22c, as, analogously, the subsection 22b with the subsection 22a. The paired assignment is implemented analogously to the exemplary embodiment according to FIGS. 1a to 1d.

[0072] The operation mode of a preferably provided spring-resilient bearing of the mecanum wheel drives 21a to 21d in combination with support means is described below, wherein the further functionality and/or width- and/or longitudinal-variability described above is not detailed—The said is, of course, also in the following embodiment variants, implemented by a multiple-part design of the chassis 5, and a corresponding controller design of the mecanum wheels 3.

[0073] FIGS. 6 and 6b again show the basic principle of a mecanum-wheeled vehicle 1 designed according to the concept of the invention. This comprises a total of four mecanum wheel drives 2 which delimit the corners of an imaginary rectangle and of which only two drives spaced apart in the direction of a longitudinal direction of the vehicle 1 can be seen in the side view. The two other mecanum wheel drives are located behind the said in the drawing plane.

[0074] Each mecanum wheel drive 2 comprises a mecanum wheel 3 including an electromotive drive (not shown) arranged thereon. All of the drives are connected in a manner known per se with control means (not shown) for individually driving the mecanum wheels 3 to ensure an omnidirectional operation. The chassis 5 is constructed from several parts for implementing a width- and/or length-variability (not shown; see previous illustrations).

[0075] It can be seen that the mecanum wheels 3, together with their drives 2, are spring-resiliently supported via energy storage means 4 against a chassis 5 which carries the mecanum wheels 3 including their drives. The energy storage means 4 are, merely by way of example, illustrated as a coil spring in the context of a simplified illustration. Of course, other springy mountings are also possible. It is essential, that at least one spring-force component oriented perpendicular to a ground U is effective between the chassis 5 and the mecanum wheels 3.

[0076] In addition to the mecanum wheels 3, the chassis 5 having a plurality of sections, carries support means 6 which are firmly connected to the said, here in form of load wheels each mounted rotatively about one rotational axis 7, as well as about one articulated axis 8 oriented perpendicular to the said.

[0077] The support means 6 may neither be driven about the rotary axis 7 nor about the articulation axis 8 directly by a separate drive, but rotate or pivot about these, respectively, as a function of a locomotion of the mecanum-wheeled vehicle 1 due to the drive of the mecanum wheels 3.

[0078] In FIG. 6a, a state without a load is shown. A weight force caused essentially by the chassis 5 in the exemplary embodiment shown, acts via the energy storage means 4 onto the mecanum wheels 3, such that, in the state shown, they are supporting said total weight force on the ground. The support faces 9 (desired contact areas with the ground), which are formed by the support means 6, more precisely by the load wheels, are spaced apart from the ground U.

[0079] FIG. 6b shows the mecanum-wheeled vehicle 1 according to FIG. 1a having a payload (load) 10 attached. The said has a weight force F of X Nm. Due to the payload 10 or due to its weight force F, respectively, the energy storage means 4 are tensioned by traveling a spring path in which the chassis 5, with the load 10, automatically shifts downwards in the direction of the weight force against the spring force of the energy storage means 4 until the support means 6 touch on the ground with their support face 9. There remains a small residual spring path of the energy storage means for compensating unevenness of the ground U (residual spring capacity). The weight force to be supported via the mecanum wheels 3 is limited by appropriate selection of the energy storage means 4 and the residual spring path and residual spring capacity, respectively. In other words, only a portion of the weight force of the payload 10 is supported on the ground via the mecanum wheels and the other part is supported on the ground via the support means. The energy storage means 4 are selected in such a way that, with respect to the payload 10 or the corresponding total weight, sufficient traction of the mecanum wheels 3 on the ground U is provided in order to propel the mecanum-wheeled vehicle (omnidirectionally).

[0080] Particular preference is given to an embodiment in which the pre-tensioning of the energy storage means 4, in particular as a function of the payload 10 to be loaded, is adjustable and/or a pre-tensioning of optional support energy storage means (not shown herein) is adjustable by which the support means 6 may be springy-resiliently mounted against the chassis 5, if needed. It is also conceivable to adjust the spacing of the support face in relation to the state according to FIG. 1a, without load, for adjusting the spring path and, thus, a residual spring path of the spring, relative to the ground.

[0081] At least one of the abovementioned settings is, most preferably, carried out as a function of the weight force to be determined or of a weight force component of the load 10 to be determined. For this purpose, measuring devices (force measuring means) 11 can be provided, for example, on the chassis 5 having a plurality of sections, by which the weight force of a payload can be determined. Depending on this weight force, which can alternatively also be determined outside the mecanum-wheeled vehicle 1, then, one of the above-mentioned settings is carried out manually or via actuator means, wherein it is very particularly preferred if this is performed automatically as a function of a sensor signal of the measuring devices 11 by corresponding controls of the actuator means by control means.

[0082] FIG. 7 shows a possible embodiment of a mecanum-wheeled vehicle 1, which is designed according to the concept of the invention, viewed from the bottom. There can be seen the four mecanum wheel drives 2, which delimit the corners of an imaginary rectangle, each comprising one mecanum wheel 3, which can be driven by a drive, here in each case one electromotive drive 12, for ensuring an omnidirectional operation. Therein, the drives 12 are driven by control means 13 in an individual direction and/or at an individual speed.

[0083] Each mecanum wheel 3 comprises a plurality of preferably barrel-shaped rollers arranged distributedly over a circumference of the wheel, the roller rotational axles of which are disposed angularly with respect to the mecanum wheel rotational axles, wherein preferably the mecanum wheel rotational axles of two adjacent mecanum wheels are aligned, and the mecanum wheel rotational axes of two mecanum wheel pairs are arranged in parallel to one another.

[0084] The chassis 5 comprising a first and a second chassis section 21a and 21b which can be adjusted relative to one another along the first adjustment axis E1 by control of the mecanum wheels 3, can be seen, against which the mecanum wheel drives 2 are mounted resiliently. The chassis 5 also bears support means 6 for carrying a load.

[0085] FIG. 8, in a highly schematic form, shows a preferred embodiment of a mecanum-wheeled vehicle 1. The mecanum wheel drives 2 are pivotally mounted on the chassis 5 via support arms 14. Respective energy storage means 4 in the form of torsion springs are assigned to the support arm 14, the torsion springs preferably being pre-tensionable by separate drives (not shown) for varying the pre-tensioning of the energy storage means. Of course, in addition to or as an alternative to torsion springs, differently shaped springs are also usable, e.g. gas pressure springs or coil springs.

[0086] Here also, it can be seen that, in addition to the mecanum wheels 3, support means 6 are provided, by which a part of a payload to be carried can be supported on a ground.

[0087] FIG. 9 shows, in a highly schematic view, a mecanum-wheeled vehicle 1, which corresponds, in its basic construction, to the exemplary embodiment according to FIGS. 1a to 2. On the chassis 5, there are lifting means 15 (distance varying means) for changing a spacing between a resting surface 17 defined by the lifting means 15 for a load to be transported, and the chassis 5. In the specific embodiment, the lifting means 15 comprise a lifting fork 16 which is arranged so as to be adjustable in height relative to the chassis 5 using, for example, an electromotive drive.

[0088] Alternative lifting means 15, for example in the form of platforms which are height-adjustable via a piston-cylinder arrangement, a spindle drive or a scissor-type hinge drive, or the like, can be implemented additionally or alternatively. The drives preferably comprise a motor, in particular an electric motor.

[0089] FIG. 10 shows an alternative embodiment of a mecanum-wheeled vehicle 1 including mecanum wheel drives 2 as well as support means 6, which are lifted off from the ground when not being charged with a payload, in analogy to the exemplary embodiment according to FIGS. 1a and 1b. The support means 6 comprise rotatably and steerably arranged rollers, which are fixed to a height-adjustable chassis section of the chassis 5, which in the exemplary embodiment shown, is designated as a support element 18, which, in turn, is fixed in a height-adjustable manner on the chassis 5. In other words, the support means 6 are fixed on the chassis 5 so as to be height-adjustable. The support frame 18 is supported on the chassis 5 via a spring element 19 and serves to receive a payload. Therein, the spring stiffness of the spring element 19 is less than the spring stiffness of the energy storage means 4, whereby the support element 18 lowers itself when the load is applied until the support means 6 or their support face, respectively, reach the ground. In this state, thus, a residual spring path of the energy storage means 4 is ensured, such that only a partial weight force is supported on the ground via the mecanum wheels 3.