CN111829714A

CN111829714A - Multi-degree-of-freedom force and moment sensor and robot

Info

Publication number: CN111829714A
Application number: CN202010735106.1A
Authority: CN
Inventors: 姜皓; 李书涵; 王世全; 安然; 李学森
Original assignee: Feixi Technology Co ltd; Flexiv Robotics Ltd
Current assignee: Feixi Technology Co ltd; Flexiv Robotics Ltd; Shanghai Flexiv Robotics Technology Co Ltd
Priority date: 2020-07-28
Filing date: 2020-07-28
Publication date: 2020-10-27
Anticipated expiration: 2040-07-28
Also published as: CN111829714B

Abstract

A multiple degree of freedom force and moment sensor is provided. The multiple degree of freedom force and moment sensor includes a first rigid plate, a second rigid plate, a plurality of springs coupled between the first rigid plate and the second rigid plate, and signal pairs disposed between the first rigid plate and the second rigid plate, the signal pairs configured to detect relative displacement of the first and second rigid plates in a plurality of directions.

Description

Multi-degree-of-freedom force and moment sensor and robot

Technical Field

The present application relates to force and moment sensor technology, and more particularly, to multiple degree of freedom force and moment sensors and robots.

Background

Most existing force and moment sensors use contact-based strain gauges to convert local structural strains caused by bulk forces and/or moments into electrical signals that are then amplified. Strain gauges are usually glued to these partial structures, and the force and moment applied to the force and moment sensors are finally determined by the corresponding electrical signals obtained by the strain gauges' sensitivity to deformation. Such as chinese application No. 201210589784.7, discloses such a six-dimensional force and moment sensor having a strain gauge bonded to a mechanical structure. However, each strain gauge is sensitive only to a unique deformation mode and is insensitive to other deformations. This makes these sensors less widely used in robotics, automation, and laboratories.

Some recent products and research have focused on non-contact sensing methods such as capacitive, inductive and optical solutions, such as korean application laid-open No. KR1020130126082A, and US patent No. US10260970B2, all disclosing such force and torque sensors. Instead of providing a conversion member (e.g., a strain gauge) that converts deformation into an electrical signal at a local structure where deformation is most severe, such a scheme is to place the conversion member at a position having the maximum displacement and convert the sensed displacement into an electrical signal. For different application scenarios, different total ranges of three orthogonal forces and three orthogonal moments may be required, whereby the required mechanical structure is to be designed with the ability to balance these forces and moments. However, few existing technologies have demonstrated this capability in its design. In practice, the deformations of the structure caused by different forces and moments are strongly coupled, so that it is difficult to individually adjust the detection capability of the sensor for a single force and moment without affecting the other forces and moments.

Therefore, there is a need for an improved six degree of freedom force and moment sensor.

Disclosure of Invention

Various aspects of the present application will be described briefly as follows to provide the most basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects, but to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

According to one aspect of the present application, a multiple degree of freedom force and moment sensor is provided. The multiple degree of freedom force and moment sensor may include a first rigid plate; a second rigid plate; a plurality of elastic members connected between the first rigid plate and the second rigid plate; and a signal pair disposed between the first rigid plate and the second rigid plate, configured to detect relative displacement of the first rigid plate and the second rigid plate in a plurality of directions. Each of the plurality of springs may include a first column portion and a second column portion, wherein a first end of the first column portion is connected to the first rigid plate and a first end of the second column portion is connected to the second rigid plate, and the first column portion and the second column portion each extend substantially in an axial direction of the multi-degree of freedom force and moment sensor. Each of the elastic members further includes a connecting portion for connecting the first columnar portion and the second columnar portion, and at least a portion of the connecting portion extends substantially in a direction perpendicular to an axial direction of the multi-degree-of-freedom force and moment sensor.

According to yet another aspect of the present application, yet another multiple degree of freedom force and moment sensor is provided. The multi-degree-of-freedom force and moment sensor comprises a first rigid plate; a second rigid plate; a plurality of elastic members connected between the first rigid plate and the second rigid plate; a signal pair disposed between the first rigid plate and the second rigid plate, configured to detect relative displacement of the first rigid plate and the second rigid plate in a plurality of directions; wherein the plurality of elastic members are disposed at edge portions of the first rigid plate and the second rigid plate. Each of the elastic members may include a first columnar portion and a second columnar portion, wherein a first end of the first columnar portion is connected to the first rigid plate, a first end of the second columnar portion is connected to the second rigid plate, and the first columnar portion and the second columnar portion extend substantially in an axial direction of the multi-degree-of-freedom force and moment sensor. Each of the elastic members further includes a connecting portion for connecting the first columnar portion and the second columnar portion. The connecting portion is shaped such that a first length of the connecting portion is greater than a height thereof in an axial direction of the multi-degree-of-freedom force and moment sensor, wherein the first length is a length of a projection of the connecting portion onto a plane perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor.

According to yet another aspect of the present application, there is also provided a robot. The robot comprises a plurality of connecting rods and an end effector which are connected in sequence, wherein the end effector comprises any one of the multi-degree-of-freedom force and moment sensors described above.

Drawings

Embodiments of the present application will be described in detail below with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view of a multiple degree of freedom force and moment sensor according to one embodiment of the present application.

FIG. 2 is a cross-sectional schematic view of an exemplary spring that may be used with the multiple degree of freedom force and moment sensor shown in FIG. 1.

Fig. 3 schematically shows a cross-sectional view of a semi-annular connection.

Fig. 4 schematically shows a cross-sectional view of a connection according to an example of the application.

Fig. 5 schematically shows a cross-sectional schematic view of a connection according to yet another example of the present application.

Fig. 6 schematically shows a cross-sectional view of a connection according to yet another example of the present application, wherein the connection is beam-shaped.

FIG. 7 is a schematic diagram of another spring for a multiple degree of freedom force and moment sensor, according to an embodiment of the present application.

Fig. 8 schematically illustrates a cross-sectional view of the connection portion 803 shown in fig. 7.

FIG. 9 is a perspective view of a multiple degree of freedom force and moment sensor 200 according to one embodiment of the present application.

Fig. 10 illustrates an exemplary robot 900 including multiple degree of freedom force and moment sensors in accordance with embodiments of the present application.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description given includes specific details for the purpose of providing a thorough understanding of the various concepts. It will be apparent, however, to one skilled in the art that these concepts may be practiced without these specific details.

FIG. 1 is a schematic view of a multiple degree of freedom force and moment sensor 100 according to one embodiment of the present application. As shown, the multiple degree of freedom force and moment sensor 100 includes a first rigid plate 10, a second rigid plate 20, a plurality of springs 30, and a plurality of signal pairs (not shown). A plurality of elastic members 30 are disposed between the first rigid plate 10 and the second rigid plate 20, wherein each elastic member 30 is connected to the first rigid plate 10 via one end thereof and to the second rigid plate 20 via the other end thereof, for example. A plurality of signal pairs are arranged on the first rigid plate 10 and the second rigid plate 20 to detect the relative displacement of the two plates.

In one example, when an external force acts on the multi-degree-of-freedom force and moment sensor 100, the first rigid plate 10 and the second rigid plate 20 keep their shapes substantially unchanged due to their higher rigidity, and the elastic member 30 may deflect and deform in the horizontal and/or vertical directions, which causes the first rigid plate 10 and the second rigid plate 20 to move relatively. The material of the elastic member 30 is typically a metal material, such as stainless steel, but other materials such as plastic or rubber may be used in some embodiments. The signal pair arranged is capable of detecting a relative movement of the first rigid plate 10 and the second rigid plate 20.

FIG. 2 is a cross-sectional schematic view of an exemplary spring that may be used with the multiple degree of freedom force and moment sensor 100 shown in FIG. 1. As shown in fig. 2, the elastic member 30 includes a first columnar portion 301, a second columnar portion 302, and a connecting portion 303. The first columnar portion 301 is connected to the first rigid plate 10 via a first end 301a thereof, and the second columnar portion 302 is connected to the second rigid plate 20 via a first end 302a thereof. The first columnar portion 301 is connected to the connecting portion 303 via the second end 301b thereof, and the second columnar portion 302 is connected to the connecting portion 303 via the second end 302b thereof. As shown, the first columnar portion 301 and the second columnar portion 302 are configured to extend substantially in the axial direction of the multi-degree-of-freedom force and moment sensor 100. For ease of description, FIG. 2 illustrates a coordinate system associated with sensor 100 that includes an X, Z axis, where the Z axis is parallel to the axial direction of the multi-degree of freedom force and moment sensor 100. The Y-axis is not shown, but it should be understood that the Y-axis is perpendicular to the plane formed by the X-axis and the Z-axis, X, Y and the Z-axis are also sometimes described herein as X, Y and the Z-direction, the plane perpendicular to the Z-axis also being referred to as the XY-plane.

It should be understood that the expression "extends substantially in the axial direction of the multiple degree of freedom force and moment sensor 100" means that the first columnar portion 301 and the second columnar portion 302 may deviate from the axial direction within a certain range while extending in the axial direction of the multiple degree of freedom force and moment sensor 100. Further, the term "columnar portion" refers to a member disposed between the rigid plate and the connecting portion in the present application, and a columnar shape is one of realizable shapes thereof, but is not limited thereto, and for example, the

columnar portions

301, 302 may be a helical structure or the like extending in the axial direction of the force and moment sensor 100 with multiple degrees of freedom. According to this example, at least a portion of the connection portion 303 extends in an axial direction substantially perpendicular to the multi-degree-of-freedom force and moment sensor 100, i.e., on the XY plane of the coordinate system in the drawing.

In some embodiments, the connecting portion has a ring shape. The connection shown in fig. 2 is annular. As shown in fig. 2, one side of the outer surface of the connecting portion 303 is connected to the second end 301b of the first column portion 301, and the other side of the outer surface of the connecting portion 303 is connected to the second end 302b of the second column portion 302. Fig. 3 schematically shows a cross-sectional view of the semi-annular connection 403. As shown, one end of the semi-annular connecting portion 403 is connected to the second end 301b of the first cylindrical portion 301, and the other end of the connecting portion 403 is connected to the second end 302b of the second cylindrical portion 302.

In some examples, the connection may include a first portion and a second portion, wherein the first portion extends in a direction substantially perpendicular to an axial direction of the multi-degree of freedom force and moment sensor. Fig. 4 schematically shows a cross-sectional view of a connection part 503 according to this example. As shown in fig. 4, the first portion 501 extends in a direction substantially perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor, i.e., extends on the XY plane of the coordinate system in the drawing; the

second portions

502a and 502b extend from the first portion 501 to the second end 302b of the second cylindrical portion 302, respectively. For example, the

second portions

502a and 502b extend from both ends of the first portion 501 to the second end 302b of the second cylindrical portion 302, respectively. The first pillar portion 301 is connected to the middle of the first portion 501. Fig. 5 schematically shows a cross-sectional view of a further connection 603 according to this example. As shown in fig. 5, the first section includes a first sub-section 601a and a second sub-section 601b, the first sub-section 601a being connected to the second end 301b of the first column portion 301 and the second sub-section 601b being connected to the second end 302b of the second column portion 302 b. The first and

second subparts

601a, 601b each extend in a direction substantially perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor 100, i.e., in the XY plane of the coordinate system in the figure. The second section 602 is connected between the first subsection 601a and the second subsection 601 b. In the example shown in fig. 5, the second portion 602 is connected to the ends of the first sub-portion 601a and the second sub-portion 601b in different extending directions, and in practical applications, the second portion 602 may be configured in any suitable shape as required.

Fig. 6 schematically shows a cross-sectional view of an alternative example of a connection, wherein the connection is beam-shaped. As shown in fig. 6, the connection portion 703 is a beam substantially perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor 100, that is, a beam substantially located on the XY plane of the coordinate system in the drawing. One side of the connecting portion 703 is connected to the first columnar portion 301, and the other side opposite to the one side is connected to the second columnar portion 302.

It is to be understood that the connections shown in fig. 3, 4, 5 and 6 are only intended to illustrate schematically different variants of the connection, and are not given the exact shape and proportions of the connection.

According to some examples of the present application, a plurality of elastic members may be disposed at edge portions of the first and second

rigid plates

10 and 20. In yet other embodiments of the present application, a plurality of elastic members may be disposed near the center of the first rigid plate 10 and the second rigid plate 20. When the elastic member is disposed near the center of the

rigid plates

10 and 20, the sensor 100 has a small sensing capability to the moment, and when the elastic member is disposed near the edge portions of the

rigid plates

10 and 20, the sensor 100 has a large sensing capability to the moment. By adjusting the radial position of the resilient member on the sensor 100, the sensing capability of the sensor 100 to torque and the sensing capability to force can be adjusted to the appropriate ratio.

Referring to fig. 1, a plurality of elastic members 30 are disposed at edge portions of a first rigid plate 10 and a second rigid plate 20 of a multi-degree-of-freedom force and moment sensor 100. Each elastic member 30 has a first columnar portion 301 and a second columnar portion 302 extending substantially along the axial direction of the multi-degree-of-freedom force and moment sensor 100, and a connecting portion 303 extending substantially in a direction perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor 100.

When a force is applied to the multi-degree-of-freedom force and moment sensor 100, the elastic member 30 is deformed in the Z direction, the X direction, or the y direction (see fig. 2 to 6). The deformations in the X and Y directions allow signals provided on the multiple degree of freedom force and moment sensor 100 to sense forces in the X and Y directions as well as moments about the Z axis. The deformation in the Z direction allows multiple degrees of freedom force and signal pairs of the moment sensor 100 to sense moments about the X and Y axes, as well as forces along the Z direction. In the case where there are different force and moment sensing ranges required for the multi-degree-of-freedom force and moment sensor 100, the requirements can be accommodated by adjusting the respective heights of the two

columnar portions

301 and 302, and the connecting portion 303 in the Z-axis, the length in the XY plane, and the like.

According to further embodiments of the present application, the connection portion is shaped such that a first length L of the connection portion is greater than a height H of the connection portion in an axial direction of the multi-degree of freedom force and moment, wherein the first length L is a length of a projection of the connection portion on a plane perpendicular to the axial direction of the multi-degree of freedom force and moment sensor. Referring to fig. 1 and 7, the multi-sensor force and moment sensor includes a first rigid plate 10, a second rigid plate 20, and a plurality of elastic members 30, the elastic members 30 being connected between the first rigid plate 10 and the second rigid plate 20. Each of the plurality of elastic members 30 includes a first columnar portion 301 and a second columnar portion 302. The first end 301a of the first columnar portion 301 is connected to the first rigid plate 10, and the first end 302a of the second columnar portion 302 is connected to the second rigid plate 20. The first pillar portion 301 and the second pillar portion 302 each extend substantially along the axial direction of the multi-degree-of-freedom force and moment sensor 10, that is, substantially along the Z-axis of the coordinate system in the drawing. The connection portion 803 is connected to the second end 301b of the first column portion 301 and the second end 302b of the second column portion 302. According to the present embodiment, the shape of the connection portion 803 is such that a first length L of the connection portion 803, which is a length of a projection of the connection portion 803 on a plane (i.e., an XY plane of a coordinate system in the drawing) perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor 100, is greater than its height H in the axial direction of the multi-degree-of-freedom force and moment sensor 100. A plurality of signal pairs (not shown) disposed between the first rigid board 10 and the second rigid board 20 are configured to detect relative displacements of the first rigid board 10 and the second rigid board 20 in a plurality of directions. According to the present application, the shapes of the connection portions described above in connection with fig. 2-6 are also applicable to the multiple degree of freedom force and moment sensors described in connection with fig. 1 and 7, and as long as the first length L is ensured to be greater than the height H, the various modifications of the connection portions will not be described in detail.

Fig. 8 schematically illustrates a cross-sectional view of the connection portion 803 shown in fig. 7. As shown in fig. 8, the contact terminal 3036 is provided on one side of the outer surface of the connection part 303, and the other contact terminal 3038 is provided on the other side of the outer surface of the connection part 303. The second end 301b of the first columnar portion 301 is connected to the connecting portion 303 via a contact terminal 3036. The second end 302b of the second cylindrical portion 302 is connected to the connecting portion 303 via the connection end 3038.

Having the connection portion 303 with the relatively long first length L and the relatively short height H means that the connection portion 303 extends mostly in a direction perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor 100 and a small portion extends in the axial direction of the multi-degree-of-freedom force and moment sensor 100. As such, the connection 303 contributes to its deflection in the Z direction due to the beam bending effect created by its majority extending in the XY plane. The thinner and longer the major portion of the connecting portion 303, the lower its rigidity in the Z direction. As shown in fig. 7, for deflection in the X direction, the connection 803 rotates mainly on the XY plane, and the rigidity of the connection between the connection 803 and the two columnar portions determines the resistance to this rotation; for deflection in the Y direction, the connection (i) may be distorted about the X axis while (ii) bending about the Z axis. The annular connection shown in fig. 7 will be taken as an example. In this example, the annular connection comprises an elongate annular portion and the connection facilitates beam bending in the Y direction; the thicker the loop in the Z direction and the thinner it in the Y direction (i.e., like a band in the XZ plane), the more susceptible the beam bending deflection in the Y direction (corresponding to the aforementioned case (i)); the thicker the loop in the Y direction and the smaller the thickness in the Z direction (i.e., like a band in the XY plane), the easier it is to deflect in a twisted (or buckled) manner about the X axis (corresponding to the aforementioned (ii) case).

Alternatively, in each of the above examples, an elastic member may be provided at an edge portion of the first rigid plate and the second rigid plate, which helps to reduce the resistance of the sensor to the moment, increasing the sensing range for the moment. In brief, the position of the elastic member may affect the rigidity and sensing range of the multi-degree-of-freedom force and torque sensor, when the elastic member is placed towards the center position of the multi-degree-of-freedom force and torque sensor, the rigidity and sensing range along the Z-axis are not affected, but the torque performance around the X-axis and the Y-axis is weakened due to the shortened moment arm; the same principle applies to forces in the X and Y directions and moments about the Z axis.

It will be appreciated that external forces and moments exerted on the multiple degree of freedom force and moment sensor may be translated into local vertical and horizontal forces on the elastic member, and thus the shapes of the first pillar portion, the second pillar portion and the connecting portion, and the connections therebetween, may be adjusted to accommodate these local forces.

In the above embodiments and examples, the signal pair may be disposed between the first rigid board 10 and the second rigid board 20, for example, and may be disposed in parallel with the elastic member 30. The signal pair includes a signal transmitter and a signal receiver. Illustratively, if 6 signal channels are provided, 3 of the signal channels can be used for sensing the relative horizontal displacement between the two rigid plates, and the other 3 signal channels can be used for sensing the vertical displacement between the two rigid plates, so that the bearing force of the sensor in X, Y, Z three directions and the bearing moment around X, Y, Z axis can be calculated according to the data. It should be understood that a person skilled in the art can determine the specific installation manner of the signal pair by the actual structure of the sensor, as long as the above-mentioned functions can be achieved, and the specific installation manner and installation position of the signal pair are not limited in the present application.

FIG. 9 is a perspective view of a multiple degree of freedom force and moment sensor 200 according to an embodiment of the present application. As shown, the sensor 200 includes a first rigid plate 11, a second rigid plate 22, and six elastic members 33. Six elastic members 33 are located between the first rigid plate 11 and the second rigid plate 22 at their outer edges, and the elastic members 33 are connected to both the first rigid plate 11 and the second rigid plate 22. The elastic member 33 may be any one of the elastic members described above with reference to the drawings, and the shape thereof will not be described for the sake of brevity. According to the example shown in fig. 9, a signal pair is provided between the rigid plate 11 and the second rigid plate 22, a part of the signal pair being used for sensing a local horizontal displacement of the elastic member 33 and a part of the signal pair being used for sensing a local vertical displacement of the elastic member 33. The number of the elastic members 33 is not limited to six, and may be more or less.

Fig. 10 illustrates an exemplary robot 900 including multiple degree of freedom force and moment sensors in accordance with embodiments of the present application. As shown in fig. 10, a plurality of link arms 901 and an end effector 902 are successively connected. The end effector 902 includes multiple degree of freedom force and moment sensors for detecting external forces and moments exerted on the end effector 902. Here, the multi-degree-of-freedom force and moment sensor may employ the multi-degree-of-freedom force and moment sensor described above in connection with the examples, such as the multi-degree-of-freedom force and

moment sensor

100 or 200. It should be understood that in other embodiments, the multiple degree of freedom force and moment sensors described above may also be installed in other components of the robot 900, for example, the multiple degree of freedom force and moment sensors may be installed in the joint actuators of the robot 900.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A multiple degree of freedom force and moment sensor, comprising:

a first rigid plate;

a second rigid plate;

a plurality of springs connected between the first rigid plate and the second rigid plate, each of the springs comprising:

a first columnar portion and a second columnar portion, a first end of the first columnar portion being connected to the first rigid plate, a first end of the second columnar portion being connected to the second rigid plate, the first columnar portion and the second columnar portion extending substantially in an axial direction of the multi-degree of freedom force and moment sensor; and

a connecting portion for connecting the first columnar portion and the second columnar portion, at least a portion of the connecting portion extending substantially in a direction perpendicular to an axial direction of the multi-degree-of-freedom force and moment sensor; and

a plurality of signal pairs disposed between the first rigid plate and the second rigid plate and configured to detect relative displacement of the first rigid plate and the second rigid plate in a plurality of directions.

2. The multiple degree of freedom force and moment sensor of claim 1 wherein the connecting portion is annular, with one side of the outer surface of the connecting portion connecting the second end of the first cylindrical portion and an opposite side of the outer surface of the connecting portion connecting the second end of the second cylindrical portion.

3. The multiple degree of freedom force and moment sensor of claim 1 wherein the connecting portion is semi-annular, one end of the connecting portion being connected to the second end of the first cylindrical portion and the other end of the connecting portion being connected to the second end of the second cylindrical portion.

4. The multiple degree of freedom force and moment sensor of claim 1 wherein the connection portion includes a first portion extending in a direction substantially perpendicular to an axial direction of the multiple degree of freedom force and moment sensor and connected to the second end of the first column portion and a second portion extending from a different location of the first portion to the second end of the second column portion.

5. The multiple degree of freedom force and moment sensor of claim 1 wherein the connection portion comprises a first portion and a second portion, the first portion comprising a first sub-portion and a second sub-portion, the first sub-portion connected to the second end of the first column and the second sub-portion connected to the second end of the second column, the first and second sub-portions each extending in a direction substantially perpendicular to an axial direction of the multiple degree of freedom force and moment sensor, the second portion connected between the first and second sub-portions.

6. The multiple degree of freedom force and moment sensor of claim 1, wherein the connection portion is beam-shaped and substantially perpendicular to an axial direction of the multiple degree of freedom force and moment sensor.

7. The multiple degree of freedom force and moment sensor of claim 1 wherein the plurality of elastic members are disposed at edge portions of the first and second rigid plates.

8. A multiple degree of freedom force and moment sensor, comprising:

a first rigid plate;

a second rigid plate;

a connecting portion connected between the first columnar portion and the second columnar portion, the connecting portion being shaped such that a first length of the connecting portion is greater than a height thereof in an axial direction of the multi-degree-of-freedom force and moment sensor, the first length being a length of a projection of the connecting portion onto a plane perpendicular to the axial direction of the multi-degree-of-freedom force and moment sensor; and

a plurality of signal pairs disposed between the first rigid plate and the second rigid plate and configured to measure relative displacement of the first rigid plate and the second rigid plate in a plurality of directions; and

wherein the plurality of elastic members are arranged at edge portions of the first and second rigid plates.

9. The multiple degree of freedom force and moment sensor of claim 8, wherein the connection portion is beam-shaped and substantially perpendicular to an axial direction of the multiple degree of freedom force and moment sensor.

10. The multiple degree of freedom force and moment sensor of claim 8 wherein the connecting portion is annular in shape with one side of an outer surface of the connecting portion connected to the second end of the first cylindrical portion and an opposite side of the outer surface of the connecting portion connected to the second end of the second cylindrical portion.

11. The multiple degree of freedom force and moment sensor of claim 10 wherein a contact end is provided on the one side of the outer surface of the connection portion and another contact end is provided on the opposite side of the outer surface of the connection portion such that the second end of the first cylindrical portion and the second end of the second cylindrical portion are connected to the contact end and the another contact end, respectively.

12. A robot comprising a plurality of links and an end effector connected in sequence, wherein the end effector comprises a multiple degree of freedom force and moment sensor comprising:

a first rigid plate;

a second rigid plate;

a plurality of signal pairs disposed between the first rigid plate and the second rigid plate configured to measure relative displacement of the first rigid plate and the second rigid plate in a plurality of directions.

13. The robot of claim 12, wherein the connecting portion is annular, one side of the outer surface of the connecting portion connecting the second ends of the first and second cylindrical portions and an opposite side of the outer surface of the connecting portion connecting the second ends of the second cylindrical portion.

14. The robot of claim 12, wherein the connection is beam-shaped and substantially perpendicular to an axial direction of the multi-degree of freedom force and moment sensor.

15. The robot of claim 12, wherein the link is configured to have a first length that is greater than its height along an axial direction of the multi-degree of freedom force and moment sensor, the first length being a length of a projection of the link onto a plane perpendicular to the axial direction of the multi-degree of freedom force and moment sensor.

16. The robot of claim 12, wherein the plurality of springs are disposed at edge portions of the first and second rigid plates.