WO2023139584A1

WO2023139584A1 - Robotic movable part

Info

Publication number: WO2023139584A1
Application number: PCT/IL2023/050066
Authority: WO
Inventors: Yonina DISON
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-01-23
Filing date: 2023-01-22
Publication date: 2023-07-27
Anticipated expiration: 2024-07-23
Also published as: IL290055A

Abstract

The present disclosure provides a flexible structure for use in linking two relatively moving parts of a robotic system. The flexible structure comprising: a primary flexible element extending between first and second ends, the first end being coupled to a first capping element and the second end being coupled to a second capping element, the primary flexible element defines an internal space spanned between the first and second capping elements; a rigid mass disposed in said internal space; a plurality of first auxiliary flexible elements, each comprises an end being coupled to either (i) said first capping element and/or (ii) a first part of the primary flexible element, and an opposite end thereof being coupled to said rigid mass; and a plurality of second auxiliary flexible elements, each comprises an end being coupled to either (i) said second capping element and/or (2) a second part of the primary flexible element, and an opposite end thereof being coupled to said rigid mass; wherein one or more of said plurality of first and second auxiliary flexible elements reside in said internal space.

Description

ROBOTIC MOVABLE PART

TECHNICAL FIELD

The presently disclosed subject matter relates to the field of robotic structures and, more particularly, but not exclusively, to the field of flexible and movable robotic structures.

BACKGROUND

Robots are machines, usually programmable, that can perform a complex series of actions automatically that typically resemble human functions. Mobile robots or portions thereof have the capability to move around in their environment. For this purpose, the robot may include one or more articulating joints designed for allowing rotational motion, translational (linear) displacement or multi/infinite degree of freedom movements (e.g., in continuum robots).

Spring-based structures are frequently used in robotic applications and devices due to their flexibility. Flexibility governed by springs typically has an undefined center of gravity.

Therefore, there is a growing need to provide a new flexible structure for use in linking two relatively moving parts of a robotic system.

References considered to be relevant as background to the presently disclosed subject matter are briefly described below. Acknowledgement of the references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.

US Application Publication No. US20090012648A1 discloses a robotic arm comprising a plurality of segments, each comprising articulated links, and means for causing each segment to bend so the arm can follow a serpentine path. A helical spring is provided coaxially with the arm to urge the links to an initial datum position, and to distribute the bending over the links of each segment.

CN Utility Model No. CN212170407U discloses a modularization software robot, including the pressure spring, and fix two end covers at the pressure spring both ends, it is inboard to establish the relative one side of two end covers, the opposite side is the outside, there are a plurality of mounting holes along the circumference equipartition on the end cover, a plurality of shape memory alloy silk that are provided with of one-to-one in a plurality of mounting holes of end cover, the pressure spring is located a plurality of shape memory alloy silk peripheries, the both ends of shape memory alloy silk are fixed respectively in two end cover outsides, through circular telegram to different shape memory alloy silk, make shape memory alloy silk compressed, thereby make two end covers at both ends produce the skew of position, realize the various deformations of software robot; and the resetting of the two end covers is realized through a pressure spring. The utility model has the advantages that: the flexible deformation and large deformation range of the soft robot are realized.

CN Application Publication No. CN110587589A discloses a bending unit body based on SMA drive and a snake-shaped flexible robot, and relates to the technical field of flexible robots, wherein the bending unit body comprises an internal supporting assembly and a plurality of SMA springs, the internal supporting assembly comprises a supporting piece, two spherical hinge devices and two joint end covers, each joint end cover comprises an end plate and a connecting shaft, one end of each connecting shaft is connected with the corresponding end plate, and the other end of each connecting shaft is connected with the corresponding supporting piece through the corresponding spherical hinge device; a plurality of spring steel plates are arranged at two ends of the supporting piece, and the other ends of the spring steel plates are in contact with the end plates; the two ends of the SMA spring are respectively connected with the two end plates. The snake-shaped soft robot is characterized in that a plurality of bending unit bodies are sequentially connected to form a straight line and comprise modularized torsion unit bodies. The bending unit body and the twisting unit body are arranged in a modularized mode, the structure is simple, the manufacture is convenient, the snakeshaped robot, the bionic trunk and the like can be assembled, the robots with different functions are assembled, and the bending unit body and the twisting unit body have great use value and popularization significance in production and life.

US Application Publication No. US20120018962A1 discloses a stiffness control system and apparatus includes one or more stiffness elements which are each activated by a smart actuator including a smart material which may be one of a shape memory alloy (SMA), a magnetorheological (MR) fluid, an electrorheological (ER) fluid, and a piezo-stack. The stiffness control system includes a first and second interface adaptable to transmit input loads and a plurality of stiffness elements. A first stiffness element is operatively connected to the first and second interfaces and is continuously responsive to a change in system operating characteristics including input loads. A second stiffness element is selectively activated by the smart actuator so as to selectively respond to a change in system conditions. The continuous response of the first stiffness element can be selectively combined with the activated response of the second stiffness element to dynamically control system stiffness.

GENERAL DESCRIPTION

The present disclosure provides a flexible structure for use in linking two relatively moving parts of a robotic system.

The term "spring" will be used herein to refer to a resilient component and/or device, e.g., a helical metal coil, that can be pressed or pulled while configured to return to its initial shape when released.

Provided by one aspect of this disclosure is, a flexible structure comprising: a primary flexible element extending between first and second ends, the first end being coupled to a first capping element and the second end being coupled to a second capping element, the primary flexible element defines an internal space spanned between the first and second capping elements; a rigid mass disposed in said internal space; a plurality of first auxiliary flexible elements, each comprises an end being coupled to either (i) said first capping element and/or (ii) a first part of the primary flexible element, and an opposite end thereof being coupled to said rigid mass; and a plurality of second auxiliary flexible elements, each comprises an end being coupled to either (i) said second capping element and/or (2) a second part of the primary flexible element, and an opposite end thereof being coupled to said rigid mass; wherein one or more of said plurality of first and second auxiliary flexible elements reside in said internal space.

Any one or more of the following features, designs and configurations can be applied to the flexible structure of the present disclosure, solely or in any combinations thereof

The primary flexible element can be a spring.

The plurality of first and second auxiliary flexible elements can be springs. • The rigid mass can be a ring-shaped element and the first and second auxiliary flexible elements can be coupled to different portions of said ring.

• The rigid mass can be a disc, namely the rigid mass has a flat and circular shape.

• The rigid mass can be a ball or sphere-shaped element and the first and second auxiliary flexible elements can be coupled to different portions of said ball or sphere.

• The rigid mass can be formed by one or more units that are integrally formed or attached one to the other.

• At least some of said plurality of first and second auxiliary flexible elements can be coupled to peripheral portions of said first and second capping elements, respectively.

• The plurality of first and second auxiliary flexible elements can be coupled to different positions of said first and second capping elements, respectively, varying in their radial position with respect to the center of the capping elements.

• The plurality of first and second auxiliary flexible elements can be coupled to the rigid mass in a closer proximity than the coupling to the capping element. Namely, the coupling points of the first and second auxiliary flexible elements to the rigid mass are much denser than their coupling points to the capping elements.

• The position of the rigid mass within said internal space can be defined by the position relation between the first capping element and the second capping element. In other words, the position relation between the capping elements is defined by the distance between the capping elements and the orientation of the capping elements.

• The position relation between the capping elements defines the tensions in the auxiliary flexible elements that results in the position of the rigid mass.

• When the structure is in a resting position, the rigid mass can be positioned substantially in a middle portion of said internal space.

• The flexible structure can further include one or more peripheral flexible elements having an end coupled to a peripheral portion of the first capping element and an opposite end of said one or more peripheral flexible elements coupled to a peripheral portion of the second capping element. Namely, the peripheral flexible elements are directly linking the first and second capping elements.

• The peripheral flexible elements can be springs.

• The peripheral flexible elements can reside within the internal space.

• The peripheral flexible elements can extend externally to the internal space.

• Some of the peripheral flexible elements extend within the internal space and some of them extend externally to the internal space.

• The first and second capping elements can be plate-shaped elements.

• The flexible structure can be configured for combination/integration with a robotic system.

• The first and second capping elements can be configured for coupling with moving robotic parts.

• The first and second capping elements may comprise coupling elements for allowing said coupling.

• At least one of the first auxiliary flexible elements comprises an end being coupled to a central portion of said first capping element and an opposite end thereof being coupled to the rigid mass or in some embodiments to a central portion of the rigid mass.

• At least one of the second auxiliary flexible elements comprises an end being coupled to a central portion of the second capping element and an opposite end thereof being coupled to said rigid mass or in some embodiments to a central portion of the rigid mass.

• Each of the plurality of the first auxiliary flexible elements comprises an end being coupled to the first capping element.

• Each of the plurality of the second auxiliary flexible elements comprises an end being coupled to the second capping element.

• Each of the plurality of the first auxiliary flexible elements comprises an end being coupled to the first part of the primary flexible element.

• Each of the plurality of the second auxiliary flexible elements comprises an end being coupled to the second part of the primary flexible element.

• The first part and said second part are on opposite sides of the rigid mass. • The first part is a first end portion of the primary flexible element being adjacent to the first capping element and said second part is a second end portion of the primary flexible element being adjacent to the second capping element.

• The plurality of first auxiliary elements and the plurality of second auxiliary elements are integrally coupled with the primary flexible element.

• Each of the plurality of first auxiliary flexible elements comprises an end being coupled to said first capping element.

• Each of the plurality of second auxiliary flexible elements comprises an end being coupled to said second capping element.

• The first and second auxiliary flexible elements are characterized by lower modulus of elasticity than the primary flexible element.

• The first and second auxiliary flexible elements are characterized by higher modulus of elasticity than the primary flexible element.

Provided by another aspect of this disclosure is a robotic assembly, comprising: at least one flexible structure, comprising: a primary flexible element extending between first and second ends, the first end being coupled to a first capping element and the second end being coupled to a second capping element, the primary flexible element defines an internal space spanned between the first and second capping element; a rigid mass disposed in said internal space; a plurality of first auxiliary flexible elements, each comprises an end being coupled to said first capping element and an opposite end thereof being coupled to said rigid mass; a plurality of second auxiliary flexible elements, each comprises an end being coupled to said second capping element and an opposite end thereof being coupled to said rigid mass; and one or more of said plurality of first and second auxiliary flexible elements reside in said internal space.

By some embodiments, the robotic assembly can be configured with any of one or more of the aforementioned features, designs and configurations that can be applied to the flexible structure of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig- 1 is a schematic illustration of a side-view of an exemplary flexible structure for use in linking two relatively moving parts of a robotic system, in accordance with the presently disclosed subject matter.

Fig- 2 is a schematic illustration of a side-view of another non-limiting example of an embodiment of the flexible structure of the present disclosure.

Fig- 3 is a schematic illustration of a side-view of another non-limiting example of an embodiment of the flexible structure of the present disclosure.

Fig. 4 is a schematic illustration of a side-view of another non-limiting example of an embodiment of the flexible structure of the present disclosure.

Fig. 5 is a schematic illustration of a side-view of another non-limiting example of an embodiment of the flexible structure of the present disclosure.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the presently disclosed subject matter. However, it will be understood by those skilled in the art that the presently disclosed subject matter may be practiced without these specific details. In other instances, well- known methods, procedures, and components have not been described in detail so as not to obscure the presently disclosed subject matter.

In the figures and descriptions set forth, identical reference numerals indicate those components that are common to different embodiments or configurations. Further, it will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. As used herein, the phrase "for example," "such as", "for instance" and variants thereof describe non-limiting embodiments of the presently disclosed subject matter. Reference in the specification to "one case", "some cases", "other cases" or variants thereof means that a particular feature, structure or characteristic described in connection with the embodiment(s) is included in at least one embodiment of the presently disclosed subject matter. Thus, the appearance of the phrase "one case", "some cases", "other cases" or variants thereof does not necessarily refer to the same embodiment(s).

It is appreciated that, unless specifically stated otherwise, certain features of the presently disclosed subject matter, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the presently disclosed subject matter, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

Bearing this in mind, attention is drawn to Fig. 1, a schematic illustration of a flexible structure 10 for use in linking two relatively moving parts of a robotic system (also referred to herein as “structure”), in accordance with the presently disclosed subject matter.

The structure 10 includes a primary flexible element 12, first and second capping elements 14, 16, a rigid mass 18 and a plurality of first and second auxiliary flexible elements 20, 22.

The arrangement is such that the primary flexible element 12 is extending between first and second ends 24, 26 thereof. The first end 24 is coupled to a first capping element 14 and the second end 26 is coupled to a second capping element 16, thereby forming a tubular-like structure. Additionally, the primary flexible element 12 defines an internal space 11 spanned between the first and second capping elements 14, 16. By way of non-limiting example, the primary flexible element 12 can be a spring (e.g., a compression spring, tension spring, torsion spring, constant force spring, etc.).

The first and second capping elements 14, 16, can be configured for coupling with one or more flexible elements described herein (e.g., the primary flexible element 12, first and second capping elements 14, 16, etc.). By way of a non-limiting example, capping elements 14, 16 can be plate-shaped elements which may be flat, undulated, curved, may comprise recesses and/or projections thereof (e.g., for coupling with one or more flexible elements described herein), etc.

In some cases, structure 10 can be configured for combination/integration with a robotic system. For instance, capping elements 14, 16, can be configured for coupling with moving robotic parts (e.g., robotic arms, snake-arm robots, etc.). For instance, the outer face of each capping element 14, 16 (e.g., respective portions of capping elements 14, 16 that are not coupled to one or more flexible elements described herein) can be coupled to a respective moving robotic part. For this purpose, each capping element 14, 16 can include one or more coupling elements configured for allowing said coupling.

Each flexible element of the plurality of first auxiliary flexible elements 20 has an end 28 that is coupled to the first capping element 14 and an opposite end 30 that is coupled to the rigid mass 18. According to certain embodiments of the presently disclosed subject matter, the rigid mass 18 can be disposed in the internal space 11 defined by the primary flexible element 12. Accordingly, the plurality of first auxiliary flexible elements 20 reside in said internal space 11.

Each flexible element of the plurality of second auxiliary flexible elements 22 has an end 32 that is coupled to the second capping element 14 and an opposite end 34 that is coupled to the rigid mass 18, which can be disposed in the internal space 11 defined by the primary flexible element 12. Accordingly, the plurality of second auxiliary flexible elements 22 reside in said internal space 11.

By way of non-limiting example, one or more flexible elements of the plurality of first and second auxiliary flexible elements 20, 22 can be springs (e.g., a compression springs, tension springs, torsion springs, constant force springs, etc., and/or combinations thereof).

In some cases, one or more flexible elements of the plurality of first and second auxiliary flexible elements 20, 22 can be coupled to peripheral portions of first and second capping elements 14, 16, respectively. The peripheral portions may be for example locations on or at a vicinity of a contour of an inner face of each capping element 14, 16 (e.g., respective portions of each capping element 14, 16 that are facing towards the internal space), locations on radial portions of each capping element 14, 16, etc. Peripheral portions of the capping elements may be referred to any position of the cap that is closer to an edge of the capping element than to the center position of the capping element. Portions that are closer to the center are central portions of the capping elements. Additionally, or alternatively, one or more flexible elements of the plurality of first and second auxiliary flexible elements 20, 22 can be coupled to different positions (e.g., locations) of the first and second capping elements 14, 16, respectively, varying in their radial position (e.g., location) with respect to the center of the capping elements 14, 16. For instance, one portion of first auxiliary flexible elements can be coupled to capping element 14 along a contour of an inner face thereof, while a second portion of first auxiliary flexible elements can be coupled to the capping element 16 at locations closer to the center thereof.

The rigid mass 18 can have various shapes, such as for example, it can be a ringshaped element, a disc (e.g., a flat and circular shaped element), a ball or sphere-shaped element, or any other element that can be configured in accordance with the presently disclosed subject matter.

In some cases, where the rigid mass 18 is a ring-shaped element, the first and second auxiliary flexible elements 20, 22 can be coupled to different portions of the ring. For this purpose, the ring may include recesses and/or projections thereon and/or one or more coupling elements configured for allowing said coupling.

In other cases, the rigid mass 18 can be a ball or sphere-shaped element wherein the first and second auxiliary flexible elements 20, 22 can be coupled to different portions of the ball or sphere. For this purpose, the ball or sphere may include recesses and/or projections thereon and/or one or more coupling elements configured for allowing said coupling.

In Fig. 1, the rigid mass has a ball or a sphere shape and the first and second auxiliary flexible elements 20, 22 are coupled to generally opposite portions thereof.

The position of the rigid mass 18 within the internal space 11 can be defined by the position relation between the first capping element 14 and the second capping element 16. For instance, the position relation between the capping elements 14, 16 can be defined by the distance between the capping elements 14, 16 and/or orientation thereof with respect to one another. Additionally, the position relation between the capping elements 14, 16 can define the tension of the auxiliary flexible elements 20, 22 and consequently the position of the rigid mass 18.

In some cases, when structure 10 is in a resting position, the rigid mass 18 can be positioned substantially in a middle portion of the internal space 11, defined by the primary flexible element 12. According to certain embodiments of the presently disclosed subject matter, structure 10 can further include one or more peripheral flexible elements 36. Each peripheral flexible element 36 can have an end 38 coupled to a peripheral portion of the first capping element 14 and an opposite end 40 coupled to a peripheral portion of the second capping element 16. The configuration is such that the peripheral flexible elements 36 directly linking the first and second capping elements 14, 16 by extending therebetween.

By way of non-limiting example, the one or more peripheral flexible elements 36 can be springs (e.g., a compression springs, tension springs, torsion springs, constant force springs, etc., and/or combinations thereof).

The one or more peripheral flexible elements 36 can be configured to reside within the internal space 11, defined by the primary flexible element 12, extend externally to the internal space 11, extend between capping elements 14, 16 while portions of the one or more peripheral flexible elements 36 are integrated/intersect with the primary flexible element 12 and/or combinations thereof (e.g., some of the peripheral flexible elements may extend within the internal space while some of the peripheral flexible elements may extend externally to the internal space).

In some cases, one or more of the flexible elements described herein can be identical or have varying parameters, such as but not limited to, varying outer and/or inner diameters, shapes, sizes, free lengths (e.g., element’s length in a resting position), number of total coils, etc. For example, one portion of the first auxiliary flexible elements 20 can have first diameter while a second portion of the first auxiliary flexible elements 20 can have second diameter, wherein the first diameter is different from the second diameter. In another example, the first and second auxiliary flexible elements 20, 22 can be identical.

In some cases, flexible structure 10 can be configured for use in linking merely one moving part of a robotic system. For example, the first capping element 14 can be coupled to a moving part of a robotic system (e.g., robotic arm) while the second capping element 16 can be coupled to a stationary structure (e.g., a structure that is fixed to one physical location).

The configuration of flexible structure 10 enables variety of movements and/or deformations thereof. Capping elements 14, 16 can be moved, rotated, tilted, etc., one with respect to the other, thereby manipulating structure 10 and one or more flexible elements comprised therein. That is, movement of one or more of the capping elements 14, 16 in any direction and/orientation causes one or more of the flexible elements to stretch, bend, tilt, etc., thereby enable maneuvering the moving parts of a robotic system coupled to the capping elements 14, 16.

It is to be noted that, in some cases, some of the elements of structure 10 may be optional. For instance, structure 10 may include merely one first auxiliary flexible element and one second auxiliary flexible element, or it may not include one or more peripheral flexible elements 36, and/or any other applicable combination of the flexible elements described herein, mutatis mutandis.

Fig- 2 is a schematic illustration of another non-limiting example of an embodiment of the flexible structure of the present disclosure. The flexible structure 210 is similar to that presented in Fig. 1, only with a rigid mass 218 in the shape of a disc. The rigid mass 218 has a first face 240 and a second face 242, the first auxiliary flexible elements 220 are coupled to the first face 240 and the second auxiliary flexible elements 222 are coupled to the second face 242.

Fig- 3 is a schematic illustration of another non-limiting example of an embodiment of the flexible structure of the present disclosure. The flexible structure 310 that is shown in Fig. 3 is similar to that of Fig. 2, and further comprises a first central auxiliary flexible elements 344 that has one end coupled to a central portion of the first capping element 314 and another end coupled to the rigid mass 318, and a second central auxiliary flexible elements 346 that has one end coupled to a central portion of the second capping element 316 and another end coupled to the rigid mass 318. The first and second central auxiliary flexible elements 344, 346 are coupled to generally two opposite portions of the rigid mass 318. In this example, the first and second central auxiliary flexible elements 344, 346 are coupled to two opposite faces 340, 342 of the rigid mass 318. Thus, the first and second auxiliary flexible element are each forming a structure of a plurality of flexible elements that extend between different peripheral portions of the capping plate and the rigid mass, these flexible elements surround a central auxiliary element that extends between a central portion of the capping element and a central portion of the rigid mass. Namely, the first and second central auxiliary flexible elements are confined by the other first and second auxiliary elements. It is to be noted that the structure that is exemplified in Fig. 3 can be applied similarly with a rigid mass in various forms, such as a sphere, a ball, a ring, or any other shape or form of the rigid mass. Fig- 4 is a schematic illustration of another non-limiting example of an embodiment of the flexible structure of the present disclosure. In this example, the flexible structure 410 comprises a primary flexible element 412 that extends between s first and second capping elements 414, 416 and defines an internal space 411 that accommodates a rigid mass 418 and a plurality of first and second auxiliary flexible elements 420, 422. The first auxiliary flexible elements 420 extend between the first capping element 414 and a first face 440 of the rigid mass 418 and the second auxiliary flexible elements 422 extend between the second capping element 416 and a second face 442 of the rigid mass 418. Peripheral auxiliary flexible elements 450 extend between the first and second capping elements 414 and 416. Namely, the peripheral auxiliary flexible elements 450 are each having one end coupled to the first capping element 414 and a second end coupled to the second capping element 416. The peripheral auxiliary flexible elements 450 in this example extend outside the internal space 411 of the primary flexible element 412, however, it is to be noted that the peripheral auxiliary elements 450 can be within the internal space 411 of the primary flexible element 412.

Fig- 5 is a schematic illustration of another non-limiting example of an embodiment of the flexible structure of the present disclosure. The flexible structure 510 that is shown in Fig. 5 is similar to that of Fig. 3, only that each of the first auxiliary element 544 is coupled to a first end portion 560 of the primary flexible element 512. The first end portion 560 is in proximity to the first capping element 514. In the same manner, each of the second auxiliary element is coupled to a second end portion of the primary flexible element 512 (not shown). In this specific and non-limiting example, the coupling of the first auxiliary elements to the primary flexible element 512 is done by coupling elements 562. It is to be understood that this coupling may also be integral coupling.

It is to be understood that the presently disclosed subject matter is not limited in its application to the details set forth in the description contained herein or illustrated in the drawings. The presently disclosed subject matter is capable of other embodiments and of being practiced and carried out in various ways. Hence, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing other structures, methods, and systems for carrying out the several purposes of the present presently disclosed subject matter.

Claims

1. A flexible structure for use in linking two relatively moving parts of a robotic system, comprising: a primary flexible element extending between first and second ends, the first end being coupled to a first capping element and the second end being coupled to a second capping element, the primary flexible element defines an internal space spanned between the first and second capping elements; a rigid mass disposed in said internal space; a plurality of first auxiliary flexible elements, each comprises an end being coupled to either (i) said first capping element or (ii) a first part of the primary flexible element, and an opposite end thereof being coupled to said rigid mass; and a plurality of second auxiliary flexible elements, each comprises an end being coupled to either (1) said second capping element or (2) a second part of the primary flexible element and an opposite end thereof being coupled to said rigid mass; wherein one or more of said plurality of first and second auxiliary flexible elements reside in said internal space.

2. The flexible structure of claim 1, wherein said primary flexible element is a spring.

3. The flexible structure of claim 1 or 2, wherein said plurality of first and second auxiliary flexible elements are springs.

4. The flexible structure of any one of claims 1-3, wherein said rigid mass is a ring-shaped element and the first and second auxiliary flexible elements are coupled to different portions of said ring.

5. The flexible structure of any one of claims 1-3, wherein said rigid mass is a disc.

6. The flexible structure of any one of claims 1-3, wherein said rigid mass is a ball or sphere-shaped element and the first and second auxiliary flexible elements are coupled to different portions of said ball or sphere.

7. The flexible structure of any one of claims 1-6, wherein at least some of said plurality of first and second auxiliary flexible elements are coupled to peripheral portions of said first and second capping elements, respectively.

8. The flexible structure of any one of claims 1-7, wherein said plurality of first and second auxiliary flexible elements are coupled to different positions of said first and second capping elements, respectively, varying in their radial position with respect to the center of the capping elements.

9. The flexible structure of any one of claims 1-8, wherein the position of the rigid mass within said internal space is defined by the position relation between the first capping element and the second capping element.

10. The flexible structure of any one of claims 1-9, when the structure is in a resting position, the rigid mass is positioned substantially in a middle portion of said internal space.

11. The flexible structure of any one of claims 1-10, further comprising one or more peripheral flexible elements having an end coupled to a peripheral portion of the first capping element and an opposite end of said one or more peripheral flexible elements coupled to a peripheral portion of the second capping element.

12. The flexible structure of claim 11, wherein said peripheral flexible elements are springs.

13. The flexible structure of claim 11 or 12, wherein said peripheral flexible elements reside within the internal space.

14. The flexible structure of claim 11 or 12, wherein said peripheral flexible elements extend externally to the internal space.

15. The flexible structure of any one of claims 1-14, wherein said first and second capping elements are plate-shaped elements.

16. The flexible structure of any one of claims 1-15, configured for combination/ integration with a robotic system.

17. The flexible structure of any one of claims 1-16, wherein said first and second capping elements are configured for coupling with moving robotic parts.

18. The flexible structure of claim 17, wherein said first and second capping elements comprise coupling elements for allowing said coupling.

19. The flexible structure of claim 18, wherein said coupling elements are formed on external faces of said capping elements facing an opposite direction than the internal space.

20. The flexible structure of any one of claims 1-19, wherein at least one of said first auxiliary flexible elements comprises an end being coupled to a central portion of said first capping element and an opposite end thereof being coupled to said rigid mass.

21. The flexible structure of any one of claims 1-20, wherein at least one of said second auxiliary flexible elements comprises an end being coupled to a central portion of said second capping element and an opposite end thereof being coupled to said rigid mass.

22. The flexible structure of any one of claims 1-21, wherein said first part and said second part are on opposite sides of the rigid mass.

23. The flexible structure of claim 22, wherein said first part is a first end portion of the primary flexible element being adjacent to the first capping element and said second part is a second end portion of the primary flexible element being adjacent to the second capping element.

24. The flexible structure of claim 22 or 23, wherein the plurality of first auxiliary elements and the plurality of second auxiliary elements are integrally coupled with the primary flexible element.

25. The flexible structure of any one of claims 1-24, wherein said first and second auxiliary flexible elements are characterized by lower modulus of elasticity than the primary flexible element.

26. A robotic assembly, comprising: at least one flexible structure, comprising: a primary flexible element extending between first and second ends, the first end being coupled to a first capping element and the second end being coupled to a second capping element, the primary flexible element defines an internal space spanned between the first and second capping element; a rigid mass disposed in said internal space; a plurality of first auxiliary flexible elements, each comprises an end being coupled to either (i) said first capping element or (ii) a first part of the primary flexible element and an opposite end thereof being coupled to said rigid mass; a plurality of second auxiliary flexible elements, each comprises an end being coupled to either (1) said second capping element or (2) a second part of the primary flexible element and an opposite end thereof being coupled to said rigid mass; and one or more of said plurality of first and second auxiliary flexible elements reside in said internal space.

27. The robotic assembly of claim 26, wherein said flexible structure is any one of claims 2-25.