WO2020238332A1

WO2020238332A1 - End effector suitable for physical interaction in unstructured environments

Info

Publication number: WO2020238332A1
Application number: PCT/CN2020/079397
Authority: WO
Inventors: 宋超阳; 万芳
Original assignee: 南方科技大学
Priority date: 2019-05-30
Filing date: 2020-03-14
Publication date: 2020-12-03
Also published as: CN110171014B; CN110171014A

Abstract

An end effector suitable for physical interaction in unstructured environments, a drive mechanism (B) of the end effector driving the fingers (C) of the end effector to perform a clamping movement, each finger of the end effector being a first base unit, a second base unit, a stack of a first base unit and multiple second base units, or a stack of multiple second base units; a first upper layer structure of the first base unit comprises a first node (1) and a first lower layer structure comprises at least three non-collinear second nodes (2), the first node and all of the second nodes forming a three-dimensional network structure by means of connecting rods (5); a second upper layer structure of the second base unit comprises at least two third nodes (3) and a second lower layer structure comprises at least two fourth nodes (4), the at least two fourth nodes and the at least two third nodes not being coplanar, and all of the third nodes and all of the fourth nodes forming a three-dimensional network structure by means of connecting rods. When clamping a target object, the fingers of the end effector adapt to geometric structures in the external environment.

Description

An end effector suitable for physical interaction in an unstructured environment

Technical field

The invention relates to the technical field of robot design, in particular to an end effector suitable for physical interaction in an unstructured environment.

Background technique

Existing robots often use rigid materials for structural design, and they have formed more mature design methods in dealing with structured environmental problems, such as industrial robots. However, when dealing with a wider range of unstructured environment interactions, this design method still has more advantages. Large limitations often require the use of more complex mechanical structures, transmission components, and drive components to achieve complex motion functions. In this process, the adaptability of the robot structure has become an important design issue.

Generally, robots with high environmental adaptability can use a single structure or only a few changes to achieve various complex functions in a wider range of application scenarios, especially in unstructured environments. This is one of the robots’ adaptability. Important manifestation.

In the design of the existing robot's end effector (mechanical claw), one of the extreme design methods is to imitate the flexible structure of the human hand, but this will introduce as many as dozens of drivers and parts like the muscles of the human hand, and the ability to control through complex motion To achieve similar functions (such as the artificial pneumatic muscle-driven manipulator produced by Shadow Robotics), this type of robot is often complex and expensive. The adaptive manipulator hopes to pass less drives (such as only one drive) and less The parts are suitable for the stable grasping of various objects with different geometric shapes, as well as more complex physical environments (such as underwater, dust-free environments).

In order to cope with the above problems, the prior art often integrates more complex mechanical structures, driving methods, sensor components, and control methods to achieve a robot design that can cope with the above difficulties. This type of design often has many difficulties, such as complex structure, high cost, numerous parts, narrow space, complex control, and difficulty in protection in special environments. However, proposing a universal adaptive robot design method is still dealing with A big challenge in the field of robot design with special application requirements in a structured environment.

Summary of the invention

In view of the deficiencies in the above problems, the present invention provides an end effector suitable for physical interaction in an unstructured environment.

The invention discloses an end effector suitable for physical interaction in an unstructured environment, including: an end effector body, a driving mechanism and two end effector fingers;

The driving mechanism is installed on the end effector body, the two end effector fingers are installed on the driving mechanism, and the driving mechanism drives the end effector fingers to make a clamping movement;

The network structure of the end effector finger adopts a spatial three-dimensional network structure, and the spatial three-dimensional network structure is based on the positions of nodes and adopts connecting rods for orderly combination in space.

As a further improvement of the present invention, the spatial three-dimensional network structure is a first basic unit, a second basic unit, a superposition of a first basic unit and a plurality of second basic units, or a superposition of a plurality of second basic units ;among them:

The first basic unit includes a first upper structure and a first lower structure, the first upper structure includes a first node, the first lower structure includes at least three second nodes, and at least three The second node is not collinear; the first node and all the second nodes form a three-dimensional network structure through connecting rods, and the connecting rods are connected between the two second nodes or the first node and the second node Between nodes

The second basic unit includes a second upper structure and a second lower structure, the second upper structure includes at least two third nodes, the second lower structure includes at least two fourth nodes, and at least two The fourth node is not coplanar with at least two of the third nodes; all the third nodes and all the fourth nodes form a three-dimensional network structure by connecting rods, and the connecting rods are connected to the two third nodes Between the two fourth nodes, or between the third node and the fourth node.

As a further improvement of the present invention, the driving mechanism is a linear motion slider driving mechanism or a rotary motion multi-link driving mechanism.

As a further improvement of the present invention, the connecting rod is a hollow flexible rod.

As a further improvement of the present invention, any one of the second nodes and the closest second node are connected by the connecting rod;

Based on the principle of proximity, the first node and one or more second nodes are connected by the connecting rod.

As a further improvement of the present invention, any one of the second nodes and one or more second nodes that are not connected to it are connected by the connecting rod;

The first node and one or more second nodes not connected therewith are connected by the connecting rod.

As a further improvement of the present invention, any of the third nodes and the third node closest to it are connected by the connecting rod;

Any one of the fourth nodes and the fourth node closest to it are connected by the connecting rod;

Based on the principle of proximity, one or more of the third nodes and one or more of the fourth nodes are connected by the connecting rod.

As a further improvement of the present invention, any one of the third nodes and one or more third nodes that are not connected to it are connected by the connecting rod;

Any one of the fourth nodes and one or more fourth nodes that are not connected thereto are connected by the connecting rod;

Any one of the third nodes and one or more unconnected fourth nodes are connected by the connecting rod.

As a further improvement of the present invention, it also includes: a sensing system;

The sensing system includes: a light source device, a photosensitive device, and an optical signal processor, and the light source device, the photosensitive device, and the optical signal processor are installed on the end effector body or the driving mechanism;

The light emitted by the light source device enters the hollow channel of the connecting rod through the light path entrance, and is transmitted to the photosensitive device through the light path exit;

The optical signal processor processes the optical signals of the light source device and the photosensitive device, and converts them into the deformation signal of the end effector finger to realize the sensing function.

As a further improvement of the present invention, a single or multiple optical fiber circuits are embedded in the hollow channel of the connecting rod;

The light emitted by the light source device enters the optical fiber loop through the light path entrance, and is transmitted to the photosensitive device through the light path exit;

Compared with the prior art, the beneficial effects of the present invention are:

The fingers of the end effector (mechanical claw) of the present invention adopt a spatial three-dimensional network structure, which is based on the position of nodes and uses connecting rods for orderly combination in space; when the end effector grabs and clamps the target item , The connecting rods of the three-dimensional network structure undergo recessed deformation in space to form an adaptability to the geometric structure of the external environment, thereby enabling the end effector to achieve physical interaction in an unstructured environment;

On top of this, the present invention can directly use the hollow structure of the connecting rod as the optical path or embed single or multiple optical fiber loops, and measure the change in the amount of light through the optical signal processor to detect the physical deformation of the connecting rod, so that the end is executed The device realizes the physical perception of the unstructured environment when interacting.

Description of the drawings

Fig. 1 is a schematic structural diagram of an end effector disclosed in an embodiment of the present invention;

2 is a schematic structural diagram of an end effector disclosed in another embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a first basic unit disclosed in an embodiment of the present invention;

Figure 4 is a schematic structural diagram of a second basic unit disclosed in an embodiment of the present invention;

FIG. 5 is a schematic diagram of a network structure of an end effector finger disclosed in an embodiment of the present invention;

6 is a schematic diagram of a network structure of an end effector finger disclosed in another embodiment of the present invention;

Figure 7 is a side cross-sectional view of a sensing system disclosed in an embodiment of the present invention;

8 is a schematic diagram of adaptive deformation before and after contact of an article X with a first basic unit according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of the first basic unit in FIG. 8 after adaptive adjustment of the article X;

10 is a schematic diagram of adaptive deformation before and after contact of an article X with a first basic unit according to another embodiment of the present invention;

FIG. 11 is a schematic diagram of an adaptive deformation of an article X after contact with a finger of an end effector according to an embodiment of the present invention.

In the picture:

A. End effector body; B. Drive mechanism; C. End effector fingers;

1. The first node; 2. The second node; 3. The third node; 4. The fourth node; 5. Connecting rod; 6. Light source device; 7. Photosensitive device; 8. Optical signal processor; 9. Light path entrance ; 10. Light path exit; 11. Light path opening that can lead into the side connecting rod; 12. Deformation signal.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the pointed device or element must have a specific orientation or a specific orientation. The structure and operation cannot therefore be understood as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

In the description of the present invention, it should also be noted that the terms "installation", "connection", and "connection" should be understood in a broad sense, unless otherwise clearly defined and limited. For example, they may be fixed connections or alternatively. Detachable connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication between two components. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in the present invention can be understood in specific situations.

The present invention will be further described in detail below in conjunction with the accompanying drawings:

As shown in Figures 1 and 2, the present invention provides an end effector suitable for physical interaction in an unstructured environment. The end effector is also called a mechanical claw and is often installed on the end flange of a robotic arm for use in robots. The actual physical interaction with the physical scene, the function is similar to the human hand, that is, the fingers of the end effector (mechanical claw); the end effector includes: the end effector body A, the driving mechanism B and two end effector fingers C; among them:

The driving mechanism B of the present invention is installed on the end effector body A, two end effector fingers C are installed on the driving mechanism B, and the driving mechanism B drives the two end effector fingers C for clamping motion.

The driving mechanism B of the present invention can be a linear motion slider driving mechanism, or a rotary motion multi-link driving mechanism. specific:

When the drive mechanism B selects the linear motion slider drive mechanism:

As shown in Figure 1, the end effector of the present invention is a common parallel two-finger machine claw, in which the palm part of the mechanical claw is equipped with two sliders that can provide reverse linear motion, and the end effector fingers can be directly C is installed on the flanges of the two sliders as the fingers of the mechanical claws. When the two sliders produce relative linear motions, they can adaptively deform the clamped target items and achieve a stable clamping effect. Through the torsional deformation of the end effector finger C itself and its own three-dimensional structure, three-dimensional adaptability and stable gripping effects can be achieved under two-dimensional drive. Such mechanical claws under traditional designs often need to increase the number of fingers. The way to achieve three-dimensional clamping.

When the drive mechanism B uses a multi-link drive mechanism with rotary motion:

As shown in Figure 2, the end effector of the present invention is another common link type two-finger mechanical claw, in which the rotary drive of the mechanical claw is transmitted to the end flange through a multi-link mechanism, which can directly transfer the end Actuator finger C is installed on the two flanges as the fingers of the mechanical claw. When the two flanges produce relative rotational movement, they can adaptively deform the clamped target object and achieve the effect of stable clamping. The rotating drive flange of some mechanical claws is equipped with an additional rotating drive so that it can rotate around the normal direction of its own flange. By adjusting it to an appropriate angle, it can improve the adaptability to the geometric shape of the clamped article. The network structure of the actuator finger C can achieve three-dimensional adaptability and motion stabilization effects through the torsional deformation of the network structure itself and its own three-dimensional structure, and reduce the number of drivers required.

At the same time, in addition to the above two forms, the drive mechanism of the present invention can also adopt other drive mechanisms that can achieve the same function.

The network structure of the end effector finger C of the present invention is a first basic unit, a second basic unit, a superposition of a first basic unit and a plurality of second basic units, or a superposition of a plurality of second basic units; wherein The network structure of the end effector finger C shown in FIG. 1 is a superposition of a first basic unit and a plurality of second basic units, and the network structure of the end effector finger C shown in FIG. 2 is a plurality of first basic units. The superposition of two basic units; at the same time, the network structure of the end effector finger C can also adopt a first basic unit structure or a second basic unit structure.

specific:

As shown in Figure 3, the first basic unit of the present invention includes a first upper structure and a first lower structure;

The first upper structure includes a first node (A) 1; the first lower structure includes at least three non-collinear second nodes 2, and the non-collinear second nodes 2 ensure that the first node 1 and the second node 2 The connection formed is a spatial three-dimensional network structure, not a flat network structure;

The first node 1 and all the second nodes 2 form a three-dimensional network structure through connecting rods 5. The connecting rods 5 are hollow flexible rods (that is, elastic or superelastic materials with high Young's modulus and deformation ratio), which can also be used to meet requirements For other solid rods, preferably a hollow flexible rod; when a solid rod is selected, a channel for the light path can be provided on the solid rod; the connecting rod 5 is connected between the two second nodes 2 or the first node 1 and the first node Between two nodes 2. Among them, all the nodes (including the first node and the second node) of the present invention are connected as a whole, and the specific connection mode of the first node 1 and the second node 2 is not limited. The specific connection between the first node 1 and the second node 2 is not limited. The connection method can be designed according to different needs.

As shown in Figure 3, the present invention shows that the lower layer is 3 second nodes (a/b), 4 second nodes (a/b/c), and n second nodes (a/b/c/... /n) The first basic unit structure; where:

Preferably, in the present invention, in the upper structure, if there is only one node in the layer, there is no link connection in the layer; in the lower structure, any second node is usually connected to the second node closest to it. Rod connection. In the upper and lower two-layer structure, based on the principle of proximity, the first node is usually connected with one or more second nodes by connecting rods.

Further preferably, the present invention can be based on the actual design needs of different scenarios. In the lower structure, any second node and one or more second nodes that are not connected to it are connected by connecting rods; in the upper and lower two-layer structure, The first node and one or more second nodes that are not connected to it are connected by connecting rods.

As shown in Figure 4, the second basic unit of the present invention includes a second upper structure and a second lower structure;

The second upper structure includes at least two third nodes 3;

The second lower structure includes at least two fourth nodes 4, and at least two fourth nodes 4 and at least two third nodes 3 are not coplanar;

All third nodes 3 and all fourth nodes 4 form a three-dimensional network structure through connecting rods 5. The connecting rods 5 are hollow flexible rods, and the connecting rods 5 are connected between two third nodes 3, two fourth nodes 4 or Between the third node 3 and the fourth node 4. Among them, all the nodes (including the third node and the fourth node) of the present invention are connected as a whole, and the specific connection mode of the third node 3 and the fourth node 4 is not limited. The specific connection between the third node 3 and the fourth node 4 The connection method can be designed according to different needs.

Preferably, in the present invention, in the upper structure, any third node and the third node closest to it are connected by a connecting rod; in the lower structure, any fourth node and the fourth node closest to it are connected by connecting rods. Rod connection: In the upper and lower two-layer structure, based on the principle of proximity, one or more third nodes and one or more fourth nodes are connected by connecting rods.

Further preferably, the present invention can be based on the actual design needs of different scenarios. In the upper structure, any third node and one or more third nodes that are not connected to it are connected by a link; in the lower structure, any The fourth node and one or more fourth nodes that are not connected to it are connected by a link; in the upper and lower two-layer structure, any third node and one or more fourth nodes that are not connected to it are connected by a link .

More preferably, it should be pointed out that this type of basic structural unit can also be regarded as a special case of the aforementioned basic structural unit, that is, between two basic units with the same lower node configuration but different single upper node configuration. combination. At this time, the structure can be simplified by connecting a single upper node of the two basic units while removing other links that are connected to the upper node but with longer lengths to avoid staggered links.

As shown in Figure 4, the present invention shows that the upper layer has 2 third nodes (A/B), the lower layer has 2 fourth nodes (a/b), and the upper layer has 2 third nodes (A/B), The lower layer has 3 fourth nodes (a/b/c), the upper layer has 2 third nodes (A/B), the lower layer has 4 fourth nodes (a/b/c/d), and the upper layer has 3 Three nodes (A/B/C), the lower layer is 3 fourth nodes (a/b/c), the upper layer is 4 third nodes (A/B/C/D), and the lower layer is 4 fourth nodes ( a/b/c/d) the second basic unit structure; where:

As shown in Figure 4a, the ABab configuration is in the form of four sides. Through the analysis method similar to the above-mentioned first specific example, it can be known that the basic structural unit can realize adaptive wrapping and movement of the external environment taking item X as an example. Stabilizing effect

For example, as shown in Figure 4b, the [Double Trilateral Double Quadrilateral] AAbbc configuration can be equivalent to a composite structural unit formed by two [tetrahedral] basic structural units Aabc and Babc through the superposition of the lower abc, and then The upper two nodes A and B are connected. Since the distance between A and a and b is relatively close, and the distance between B and c is only relatively short, it can be completed by removing the three connecting rods Ac, Ba and Bb The structure is simplified to avoid the structure of staggered connecting rods. Similar to the aforementioned analysis, it can be known that the basic structural unit can achieve the effect of adaptive wrapping and motion stabilization of the external environment taking the article X as an example.

For example, as shown in Figure 4c, the [single four-sided four-three-sided] ABabc configuration can be equivalent to a composite structural unit formed by two [tetrahedral] basic structural units Aabc and Babc through the superposition of the lower abc. However, the spatial distance between Ac and Bc is basically the same, and the spatial distance between Aa and Bb is also basically the same. In this case, the structure can be simplified by removing Ab and Ba to avoid the structure of interlacing connecting rods. This configuration can also be regarded as a Taking c as the first layer and ABba as the second layer of the pyramid-shaped basic structural unit, similar to the foregoing analysis, it can be known that the basic structural unit can achieve adaptive coverage and motion stabilization effects for the external environment taking item X as an example.

As shown in Figure 4d, the [three-four-sided double-trilateral] ABabcd configuration can be equivalent to two [pyramid-style] basic structural units Aabcd and Babcd form a composite structural unit through the superposition of the lower abcd, but The spatial distance between Aa and Ab is basically the same, and the spatial distance between Bc and Bd is also basically the same. In this case, the structure can be simplified by removing Ac, Ad, Ba, and Bb to avoid the staggered structure of the connecting rods. The analysis similar to the above shows that The basic structural unit can realize the effect of adaptive wrapping and motion stabilization of the external environment taking the article X as an example.

In other cases, other basic network structural units can be obtained by analogy based on the above analysis.

Another special case of this type of basic structural unit is when the upper and lower layers contain the same number of connecting nodes, each layer only needs to connect the adjacent nodes in turn by connecting rods to form a single closed-loop structure, and the two layers are connected to the corresponding nodes in turn by connecting rods. A three-dimensional network structure is formed, and the nodes in each layer may not be coplanar.

As shown in Figure 4e [Double-layer Trilateral] ABCabc configuration, the upper and lower layers respectively contain three connection nodes;

As shown in Figure 4f [Double-layer Quadrilateral] ABCDabcd configuration, the upper and lower layers contain four connection nodes respectively.

As shown in Figure 5, based on the above-mentioned first basic unit and second basic unit, the network structure of the end effector finger designed in the present invention can be stacked by using a first basic unit and multiple second basic units. In this way, the basic structure unit of each layer can respectively perform corresponding recessed deformations on the geometric dimensions of the different positions of the article X. The self-adaptability and motion stabilization effect of each layer are superimposed, including the self-deformation of the network structure through torsional deformation. The adaptive wrapping and motion stabilization effects comprehensively improve the adaptive wrapping and motion stabilization effects of the overall spatial network structure to the external environment. A distinctive feature of the spatial network structure of the end effector finger involved in the present invention is that it can be selected from any The lateral angle realizes geometric structure adaptation to the external environment and movement stability:

As shown in Figure 5a, the [multi-layer tetrahedral] structure: consists of the basic structural unit of the top [tetrahedron] and multiple basic structural units of the double-layer [trilateral] at the bottom;

As shown in Figure 5b [Multilayer Pyramid] structure: It consists of a [pyramid] basic structural unit on the top layer and multiple [quadrangular] basic structural units on the bottom;

According to the actual needs of different scenarios, corresponding structural design can be carried out according to the design method described in the present invention to realize the structural adaptability and motion stabilization effect of the end effector finger to the external environment.

Preferably, according to the actual design requirements of different scenarios, the geometric shape of each connecting rod can be a general straight line or a complex curve with a special design, and the cross-sectional shape of each connecting rod can be round or square. Or any other cross-sectional shape.

Preferably, each connecting rod is made of a material with a certain elasticity, that is, it can produce elastic deformation that can be detected under the action of external force. Any connecting rod can adopt a hollow structure inside. By detecting the amount of light inside the rod, the rod can be aligned. Perception of elastic deformation of pieces.

Preferably, according to the actual design needs of different scenarios, the way to realize the connection between the links at the connection node can be a general structural fixed connection (no degree of freedom, that is, no relative freedom of movement between the links), and hinge connection (a degree of freedom is The connecting rods have a relative rotation degree of freedom of movement), spherical hinge connection (three degrees of freedom, that is, there are two relative rotations between the connecting rods and one degree of freedom of movement around the axis) and other connection methods.

As shown in Figure 6, on the basis of the above-mentioned basic units, the spatial network structure of the end effector finger designed by the present invention can be combined and stacked by using multiple second basic structures. The geometric dimensions of the different positions of each layer are subjected to corresponding concave deformation, through the superposition of the self-adaptability and motion stabilization effect of each basic structure, including the adaptive wrapping and motion stabilization effect of the network structure through torsion deformation, comprehensively improve the overall The spatial network structure has the effect of self-adaptive wrapping and motion stabilization of the external environment. A significant feature of the spatial network structure of the end effector finger involved in the present invention is that it can realize geometric structure adaptation to the external environment from any lateral angle. And movement stability:

As shown in Figure 6a [a multi-layer composite] structure: it consists of a basic structural unit of [single four-sided three-sided] on the top layer and a plurality of basic structural units of a double-layer [three-sided] on the bottom;

As shown in Figure 6b [another multi-layer composite] structure: It consists of a basic structural unit of [three-four-sided double-trilateral] on the top layer and a plurality of basic structural units of a double-layer [quadrilateral] on the bottom;

According to the actual needs of different scenarios, corresponding structural design can be carried out according to the design method described in the present invention to realize the structural adaptability and motion stabilization effect of the robot body to the external environment. This method can realize the diversified robot structure.

The present invention can adopt a flexible rod with an internal optical path (that is, an elastic or superelastic material with a higher Young's modulus and deformation ratio). When the rod is deformed, it can measure the optical fiber communication in the optical path or the optical path. The change of the light flux of the optical medium realizes the measurement of the deformation of the rod, so as to realize the perception of the physical environment when the end effector fingers interact.

specific:

As shown in Figure 7, the structure shown is a sectional view of the side triangle in the basic unit; the present invention provides an end effector sensing system, including: a light source device 6, a photosensitive device 7 and a light signal processor 8, the light source device 6. The photosensitive device 7 and the optical signal processor 8 are installed on the end effector body or the driving mechanism; among them:

The connecting rod of the end effector finger is provided with a light path entrance 9 and a light path exit 10, and a light path opening 11 that can be introduced into the side connecting rod is provided at the connection point; the light source device 6, the photosensitive device 7 and the optical signal processor 8 are connected, The light source device 6 is placed at the entrance 9 of the light path, and the photosensitive device 7 is placed at the exit 10 of the light path.

When in use, the light emitted by the light source device 6 enters the hollow channel of the connecting rod 5 through the light path entrance 9 and is transmitted to the photosensitive device 7 through the light path exit 10; the optical signal processor 8 performs the optical signal processing on the light source device 6 and the photosensitive device 7 The processing is transformed into the deformation signal 12 of the end effector finger to realize the sensing function.

Further, the specific direction of the optical path of the sensing system of the present invention can be specifically designed according to actual needs. The bottom of the optical path is connected to the base part of the robot. The light source device can be a light emitting diode, and the photosensitive device can be a photosensitive sensor.

The present invention also provides another end effector sensing system, including: a light source device 6, a photosensitive device 7, and an optical signal processor 8. The light source device 6, the photosensitive device 7 and the optical signal processor 8 are installed in the end effector body or drive Institutional; among them:

The connecting rod of the end effector finger is provided with a light path entrance 9 and a light path exit 10, and the hollow channel of the connecting rod 5 is embedded with single or multiple optical fiber circuits; and the connection point is provided with a light path opening that can lead into the side connecting rod 11; The light source device 6, the photosensitive device 7 is connected to the optical signal processor 8, the light source device 6 is placed at the light path entrance 9, and the photosensitive device 7 is placed at the light path exit 10.

When in use, the light emitted by the light source device 6 enters the optical fiber loop through the light path entrance 9 and is transmitted to the photosensitive device 7 through the light path exit 10; the optical signal processor 8 processes the light signals of the light source device 6 and the photosensitive device 7 and converts them into The deformation signal of the finger of the end effector realizes the sensing function.

Examples:

The present invention uses the first basic unit as an example to describe the adaptive process, and the principle of the adaptive process of the second basic unit is the same as that of the first basic unit.

The adaptive process of the first basic unit of the present invention is:

The present invention takes Aabc in Fig. 3 as an example. When the external environment force from an article X with a certain three-dimensional geometric size is applied, the edges in contact with the article X respectively produce different degrees of elastic deformation to form a space package for the three-dimensional geometric size of the article X. Overlay to realize the adaptability of geometric shapes.

As shown in Figure 8, the external environment item X with a certain spatial geometric shape is in the blank area in the middle of a triangle Abc in [tetrahedron];

Before the contact occurs, the relative combined movement direction of the item X and the basic structural unit of the [tetrahedron type] is pointed by the dotted arrow, and the dotted arrow points to a blank area in the middle of the trilateral Abc of the basic structural unit of the [tetrahedral type];

After the contact occurs, the item X comes into contact with the trilateral Abc of the basic structural unit [tetrahedral], and the trilateral Abc produces corresponding elastic deformation; that is, the original connecting nodes A, b, and c produce a certain amount of Displaced to the positions A', b', and c', the three rods realize the adaptability to the X geometric dimensions of the article through the generated elastic deformation.

As shown in Figure 9, in the case of the schematic diagram after contact shown in Figure 8, it may be due to the uneven force indicated by the dashed arrow, plus the additional restriction from the rod A'a at point A', making the triangle A'bc rotates around the rod A'a, causing the torsional movement of the entire [tetrahedral] basic structural unit. The resulting overall deformation further enhances the adaptability to the geometric structure of the article X, as shown by the three arrows in the figure The instantaneous equalization of each force achieves the effect of stabilizing the movement of the article X.

As shown in Figure 10, the external environment items X with a certain spatial geometric shape are almost evenly distributed in the area of the triangle Abc and the triangle Aac in the tetrahedral position.

Before contact occurs, the relative combined movement direction of the item X and the [tetrahedral] basic structural unit is indicated by the dotted arrow. At this time, because the item X is relatively uniform in the [tetrahedral] basic structural unit, it is almost uniformly distributed in its triangles Abc and three at the same time. In the polygonal Aac area, that is, the dotted arrow mainly points to the direction of the rod Ac;

After the contact occurs, the article X comes into contact with the rod Ac of the [tetrahedral] basic structural unit, and the rod Ac produces corresponding elastic deformation; that is, the article X mainly contacts the rod Ac, causing the rod Ac to generate elastic deformation and form a The adaptability of the X geometry, the original connecting nodes A and c have a certain amount of displacement to the position A'and c'respectively inward.

At the same time, based on the principle of Figure 9, in the present invention, when the force applied to the connecting rods of the article X is uneven, the side on which the force is applied will form a torsion effect, so that the entire [tetrahedral] configuration also follows The torsion further strengthens the adaptive geometric wrapping of the article X, thereby achieving stable movement of the article X.

The above only shows the [tetrahedral] end effector finger. When the number of lower connection nodes exceeds three, the [polyhedral] network configuration formed by the method similar to the above can be regarded as multiple [tetrahedral]. The superposition of the basic configuration, that is, the connection nodes of the lower layer are divided into groups of three to form different basic configurations of [tetrahedron], and then superimposed on the shared link to form the corresponding [polyhedron] The composite network configuration can achieve adaptive coverage and motion stabilization effects on the external environment using item X as an example by similar methods.

The adaptive process of the second basic unit of the present invention is:

The above only shows the network structure of the first basic unit. When the second basic unit is taken as an example, that is, when the number of upper-level connection nodes is multiple, the [polyhedral] network configuration formed by the method similar to the above can be regarded as It is a superposition of multiple [tetrahedral] basic configurations; it can also achieve adaptive wrapping and motion stabilization effects on the external environment using item X as an example by similar methods.

As shown in Figure 11, taking a multi-layer pyramid network structure as shown in Figure 5b as an example, when the external environment items X come from different angles, the network structure involved in the present invention produces adaptive deformation, where a The picture shows the physical model of the network structure Aabcd, the picture b shows the adaptive deformation when the article X mainly acts from the side Aab, and the picture c shows the adaptive deformation when the article X mainly acts on the rod close to Ab. When the entire network structure produces a counterclockwise twist to make the contact surface adaptive to the side Aab, the figure d shows the adaptive deformation that occurs when the item X mainly acts from the rod close to Aa, and the entire network structure generates a clockwise twist to make the contact surface Self-adaptation is side Aab.

The above are only preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc., made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

An end effector suitable for physical interaction in an unstructured environment, characterized by comprising: an end effector body, a driving mechanism and two end effector fingers;

The driving mechanism is installed on the end effector body, the two end effector fingers are installed on the driving mechanism, and the driving mechanism drives the end effector fingers to make a clamping movement;

The network structure of the end effector finger adopts a spatial three-dimensional network structure, and the spatial three-dimensional network structure is based on the positions of nodes and adopts connecting rods for orderly combination in space.
The end effector of claim 1, wherein it is a first basic unit, a second basic unit, a superposition of a first basic unit and a plurality of second basic units, or a combination of a plurality of second basic units Superimposed; where:

The first basic unit includes a first upper structure and a first lower structure, the first upper structure includes a first node, the first lower structure includes at least three second nodes, and at least three The second node is not collinear; the first node and all the second nodes form a three-dimensional network structure through connecting rods, and the connecting rods are connected between the two second nodes or the first node and the second node Between nodes

The second basic unit includes a second upper structure and a second lower structure, the second upper structure includes at least two third nodes, the second lower structure includes at least two fourth nodes, and at least two The fourth node is not coplanar with at least two of the third nodes; all the third nodes and all the fourth nodes form a three-dimensional network structure by connecting rods, and the connecting rods are connected to the two third nodes Between the two fourth nodes, or between the third node and the fourth node.
The end effector according to claim 2, wherein the driving mechanism is a linear motion slider driving mechanism or a rotary motion multi-link driving mechanism.
The end effector according to claim 2, wherein the connecting rod is a hollow flexible rod.
The end effector of claim 2, wherein any one of the second nodes and the second node closest to the second node are connected by the connecting rod;

Based on the principle of proximity, the first node and one or more second nodes are connected by the connecting rod.
The end effector of claim 5, wherein any one of the second nodes and one or more second nodes that are not connected thereto are connected by the connecting rod;

The first node and one or more second nodes not connected therewith are connected by the connecting rod.
The end effector according to claim 2, wherein any one of the third nodes and the third node closest to the third node are connected by the connecting rod;

Any one of the fourth nodes and the fourth node closest to it are connected by the connecting rod;

Based on the principle of proximity, one or more of the third nodes and one or more of the fourth nodes are connected by the connecting rod.
The end effector according to claim 7, wherein any one of the third nodes and one or more third nodes that are not connected thereto are connected by the connecting rod;

Any one of the fourth nodes and one or more fourth nodes that are not connected thereto are connected by the connecting rod;

Any one of the third nodes and one or more unconnected fourth nodes are connected by the connecting rod.
8. The end effector according to any one of claims 1-8, further comprising: a sensing system;

The sensing system includes: a light source device, a photosensitive device, and an optical signal processor, the light source device, the photosensitive device, and the optical signal processor are installed on the end effector body or the driving mechanism;

The light emitted by the light source device enters the hollow channel of the connecting rod through the light path entrance, and is transmitted to the photosensitive device through the light path exit;

The optical signal processor processes the optical signals of the light source device and the photosensitive device, and converts them into the deformation signal of the end effector finger to realize the sensing function.
The end effector according to claim 9, wherein a single or multiple optical fiber circuits are embedded in the hollow channel of the connecting rod;

The light emitted by the light source device enters the optical fiber loop through the light path entrance, and is transmitted to the photosensitive device through the light path exit;

The optical signal processor processes the optical signals of the light source device and the photosensitive device, and converts them into the deformation signal of the end effector finger to realize the sensing function.