Laser additive manufacturing of octopus tentacle continuum robots and methods of construction

Abstract

The application discloses a laser additive manufacturing inkfish tentacle continuum robot and a construction method thereof. The continuum robot comprises a continuum robot body, and the continuum robot body comprises a plurality of inkfish tentacle cell structures. Each inkfish tentacle cell structure is formed by melting shape memory alloy powder along a length extension direction by a laser additive manufacturing technology, and is periodically arrayed and connected with each other, so that the continuum robot body is formed. Therefore, the laser additive manufacturing inkfish tentacle continuum robot is formed by the laser additive manufacturing method, and the laser additive manufacturing inkfish tentacle continuum robot with a capturing function is constructed by training the laser additive manufacturing inkfish tentacle continuum robot to perform a curling and winding behavior. The application greatly simplifies a traditional continuum robot capturing system and has a high design freedom, so that the curling and winding of a space object and a capturing task in a complex environment can be realized without integrating other mechanical structures.

Description

Technical Field

[0001] This invention belongs to the field of biomimetic continuum robot and laser additive manufacturing technology, specifically relating to a laser additive manufacturing method for a continuum robot with squid tentacles and its construction method. Background Technology

[0002] The space environment is complex and harsh, and astronauts face enormous risks and high costs when performing extravehicular activities. With the increasing frequency and depth of human space exploration, space debris, including satellite fragments and abandoned satellites, is growing, increasing the complexity of space missions and making reliable on-orbit servicing technologies increasingly important.

[0003] Continuum robots possess high structural flexibility and environmental adaptability, enabling continuous deformation and playing a vital role in unstructured environments. These significant advantages make them promising candidates for space missions. However, traditional continuum robots suffer from complex structures, difficult assembly, intricate drive mechanisms, and high manufacturing costs. Summary of the Invention

[0004] To address the shortcomings or improvement needs of existing technologies, this invention provides a laser additive manufacturing method for a continuous robot resembling a squid tentacle, which has a significantly simplified structural configuration, requires no assembly, is easy to drive, and has a high degree of design freedom, thus meeting the requirements of space mission applications.

[0005] To achieve the above-mentioned technical objectives, the present invention will adopt the following technical solution:

[0006] A laser additive manufacturing method for a continuous robot with squid tentacles as its shape includes a continuous robot body, which comprises several squid tentacle-like unit cell structures. Each squid tentacle-like unit cell structure is formed by periodically arranging and connecting with each other along the length extension direction by melting shape memory alloy powder using laser additive manufacturing technology, thereby forming the continuous robot body.

[0007] Preferably, the simulated squid tentacle unit cell structure comprises several squid tentacle-shaped characteristic cross sections evenly distributed around its own central axis, and the squid tentacle-shaped characteristic cross sections are imitation components of natural squid tentacle cross sections.

[0008] Preferably, in the squid tentacle-like unit cell structure, each squid tentacle-shaped cross-section includes a first connecting rod, a second connecting rod, and two intermediate connecting rods arranged between the first and second connecting rods; the two intermediate connecting rods are arc-shaped rods with the same geometric shape; the two intermediate connecting rods are connected at the middle position to form a bi-link system that is vertically symmetrical about the connection point; each end point of the bi-link system is connected to the end points of the first and second connecting rods respectively, and forms an angle θ with the plane where the first and second connecting rods are located, and the plane where the bi-link system is located is offset from the central axis of the squid tentacle-like unit cell structure;

[0009] The first connecting rods of each cuttlefish tentacle-shaped cross section can be directly spliced ​​or transitionally connected to each other to form a first connecting rod, and the second connecting rods of each cuttlefish tentacle-shaped cross section can be directly spliced ​​or transitionally connected to each other to form a second connecting rod.

[0010] The first and second connecting rods are parallel to each other and have the same geometric shape, both being regular polygons or rings, and the vertical center lines of the first and second connecting rods coincide with the central axis of the imitation squid tentacle unit cell structure.

[0011] Preferably, the first and second connecting rods are square in shape; the intermediate connecting rod is a parabolic rod, and the geometry of the parabolic rod satisfies:

[0012]

[0013] Where, a is the side length of the first or second connecting rod; θ is the angle formed by the plane connecting the parabolic rod and the plane containing the first and second connecting rods; x and y represent the coordinates of any point on the parabolic rod.

[0014] Preferably, the design steps of the squid tentacle-like unit cell structure are as follows:

[0015] Step 1: First, connect the two ends of a parabolic rod to the endpoints of the first connecting rod and the second connecting rod respectively. Then, perform a planar symmetry transformation on the parabolic rod along the xoz plane where the central axis of the imitation squid tentacle unit cell structure is located, thereby forming a squid tentacle-shaped cross section with squid tentacle cross section characteristics.

[0016] Step 2: Rotate the cuttlefish tentacle-shaped feature cross-sections obtained in Step 1 around the central axis of the simulated cuttlefish tentacle unit cell structure. Then, connect the first connecting rods of two adjacent cuttlefish tentacle-shaped feature cross-sections to form a first connecting rod, and connect the second connecting rods to form a second connecting rod, thus obtaining the final simulated cuttlefish tentacle unit cell structure.

[0017] Preferably, after the squid tentacles are periodically arrayed along their own length, between two adjacent squid tentacles, one is designated as the first squid tentacles and the other as the second squid tentacles. The first connecting rod of the first squid tentacles can be connected and fused with the second connecting rod of the second squid tentacles to form a whole.

[0018] Another technical objective of this invention is to provide a method for constructing a laser additive manufacturing continuum robot with a squid tentacle-like shape memory alloy as described above, using spherical nickel-titanium shape memory alloy pre-alloyed powder with a diameter not exceeding 60 μm as raw material, and employing laser powder bed fusion additive manufacturing technology to prepare the continuum robot with a squid tentacle-like shape memory alloy.

[0019] Processing parameters: laser power is 125W, scanning speed is 1200mm / s, scanning spacing is 50μm, powder layer thickness is 90μm, and spot diameter is 70μm;

[0020] The obtained squid tentacle-like continuum robot was trained to exhibit coiling and winding behavior, resulting in a final laser additive manufacturing squid tentacle-like continuum robot with capture capabilities.

[0021] Preferably, the object of the curling and winding behavior training is the individual squid tentacle unit cell structures that make up the laser additive manufacturing squid tentacle continuum robot, and the training process includes the following sequential steps: heating-loading-cooling-unloading, wherein:

[0022] Heating process: Heat each imitation squid tentacle unit cell structure to above the austenite phase transformation temperature and below the stress-induced martensite phase transformation maximum temperature, and hold for 3-5 minutes.

[0023] Loading process: Each squid tentacle unit cell structure is individually loaded. Specifically, based on the required motion posture and trajectory of the laser additive manufacturing squid tentacle continuum robot, one or more load application points are selected on the first and second connecting rods of each squid tentacle unit cell structure. The load application points on the first connecting rod and the load application points on the second connecting rod are set one-to-one. Then, a load is applied to each squid tentacle unit cell structure individually so that the corresponding squid tentacle unit cell structure can be dynamically compressed along the direction parallel to the central axis of the squid tentacle unit cell structure until the load application point on the first connecting rod of the squid tentacle unit cell structure can contact the corresponding load application point on the second connecting rod and then hold the pressure for 15-30 seconds.

[0024] Cooling process: Cool each squid tentacle-like unit cell structure under pressure to below the martensitic phase transformation temperature and hold for 3-5 minutes.

[0025] By repeating the above training process 10-30 times on each of the squid tentacle-like unit cell structures to train the curling and winding behavior, the final laser additive manufacturing squid tentacle-like continuum robot with capture function can be obtained.

[0026] Preferably, during the loading process, the specific steps for selecting the load application point on the first and second connecting rods of each squid tentacle unit cell structure are as follows: for each squid tentacle unit cell structure, firstly, select a point on the first connecting rod of any squid tentacle shape characteristic section as the load application point, and then select a point on the second connecting rod of the same squid tentacle shape characteristic section that corresponds to the load application point on the first connecting rod as the load application point of the second connecting rod.

[0027] Another technical objective of this invention is to provide an application of the aforementioned laser additive manufacturing squid tentacle continuum robot in the aerospace field, wherein the laser additive manufacturing squid tentacle continuum robot can be used for space target capture.

[0028] Based on the above-mentioned technical objectives, the present invention has the following advantages compared with the prior art:

[0029] 1. The laser additive manufacturing continuum robot for mimicking squid tentacles described in this invention is achieved by analyzing the structural features of a naturally optimized section of a squid tentacle with entanglement and capture functions and then optimizing its structure. Compared with traditional continuum robots, the structure is greatly simplified. The structural configuration of the continuum robot for mimicking squid tentacles can be freely adjusted according to the actual needs of the space mission, based on the functional equations abstracted from the key biological geometric configurations, resulting in extremely high design freedom. Using laser additive manufacturing technology, the continuum robot for mimicking squid tentacles can be integrally formed without assembly and can perform functional actions without integrating other auxiliary mechanical structures.

[0030] 2. The laser additive manufacturing technology used in this invention can achieve near-net-shape forming, which greatly improves material utilization and reduces production costs.

[0031] 3. The laser additive manufacturing of the squid tentacle continuum robot described in this invention is made of shape memory alloy material in an integrated manner. According to the actual needs of the space mission, the squid tentacle continuum robot can be trained to perform targeted curling and winding behavior. The shape memory effect of the shape memory alloy material under thermal excitation conditions is used to achieve active control of the shape, so as to obtain the corresponding motion posture and trajectory, which has strong environmental adaptability. Attached Figure Description

[0032] Figure 1 This is a three-dimensional schematic diagram of a single cell structure of a squid-like tentacle according to the present invention.

[0033] Figure 2 This is a frontal view of a single cell structure of a squid-like tentacle according to the present invention.

[0034] Figure 3 This is a top view schematic diagram of a single cell structure of a squid-like tentacle of the present invention.

[0035] Figure 4 This is a three-dimensional schematic diagram of the laser additive manufacturing of a squid tentacle-like continuous robot according to the present invention.

[0036] Figure 5 This is a front view schematic diagram of the laser additive manufacturing of the squid tentacle continuum robot according to the present invention.

[0037] Figure 6 This is a top view schematic diagram of the laser additive manufacturing of a squid tentacle-like continuum robot according to the present invention.

[0038] Figure 7 This is an initial morphological image of the laser additive manufacturing process of the squid tentacle-like continuous robot of the present invention after it has been formed.

[0039] Figure 8 This is a topographic image of the laser additive manufacturing of the squid tentacle continuum robot of the present invention after training in curling and winding behavior.

[0040] Figure 9 This is a topographical image of the laser additive manufacturing of the squid tentacle continuum robot of the present invention, which is in a state of entanglement and capture after being induced by shape memory.

[0041] Figure 10 The image shows the DSC curve of the matrix material for the laser additive manufacturing of the squid tentacle continuum robot of this invention.

[0042] Figure 11This invention relates to the laser additive manufacturing of a squid tentacle-like continuous robot, and explores the influence of different squid tentacle unit cell structures on the entanglement and grasping function. In the figure: (a) shows the squid tentacle unit cell structure where the side length a = 3mm of the first or second connecting rod, and the angle θ = 30° formed by the parabolic rod connecting to the plane containing the first and second connecting rods; (b) shows the squid tentacle unit cell structure where the side length a = 5mm of the first or second connecting rod, and the angle θ = 30° formed by the parabolic rod connecting to the plane containing the first and second connecting rods; (c) shows the squid tentacle unit cell structure... In the cell structure, the side length a = 7 mm of the first or second connecting rod, and the angle θ formed by the parabolic rod and the plane containing the first and second connecting rods is 30°; (d) indicates that in the unit cell structure of the squid tentacles, the side length a = 5 mm of the first or second connecting rod, and the angle θ formed by the parabolic rod and the plane containing the first and second connecting rods is 15°; (e) indicates that in the unit cell structure of the squid tentacles, the side length a = 5 mm of the first or second connecting rod, and the angle θ formed by the parabolic rod and the plane containing the first and second connecting rods is 45°. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise specifically stated, the relative arrangement, expressions, and values ​​of components and steps set forth in these embodiments do not limit the scope of the present invention. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0044] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used here to describe the spatial positional relationship of a device or feature as shown in the figure with other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figure. For example, if the device in the figure is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations).

[0045] like Figures 4 to 5 As shown in the figure, the laser additive manufacturing of the squid tentacle-like continuous robot of the present invention includes a continuous robot body, which comprises a plurality of squid tentacle-like unit cell structures. Each squid tentacle-like unit cell structure is formed by periodically arranging and connecting with each other along the length extension direction by melting shape memory alloy powder using laser additive manufacturing technology, thereby forming the continuous robot body. In the figure, the length extension direction of the continuous robot body is the Z-axis direction of the three-dimensional coordinate system XYZ, and the shape memory alloy powder used is a spherical nickel-titanium shape memory alloy pre-alloyed powder with a diameter not exceeding 60 μm.

[0046] like Figure 1-3As shown, the simulated squid tentacle unit cell structure comprises several squid tentacle-shaped feature sections evenly distributed circumferentially around its central axis. Each squid tentacle-shaped feature section is a contoured component of a natural squid tentacle section, and is arranged in a hollow rectangular shape. It includes a first connecting rod, a second connecting rod, and two intermediate connecting rods arranged between the first and second connecting rods. The first and second connecting rods are parallel to each other, and the two intermediate connecting rods are arc-shaped rods with the same geometric shape. The two intermediate connecting rods are connected at the middle position to form a vertically symmetrical two-link system about the connection point. Each end of the two-link system is connected to the end of the first and second connecting rods respectively. The first connecting rods are connected to the plane containing the first and second connecting rods, forming an angle θ. The plane containing the two connecting rods is offset from the central axis of the squid tentacle unit cell structure, meaning there is no intersection between the plane containing the two connecting rods and the central axis of the squid tentacle unit cell structure. The first connecting rods of each squid tentacle-shaped cross-section can be directly spliced ​​or transitionally connected to form the first connecting rod, and the second connecting rods of each squid tentacle-shaped cross-section can be directly spliced ​​or transitionally connected to form the second connecting rod. The first and second connecting rods are parallel to each other and have the same geometric shape, both being regular polygons or rings, and the vertical center lines of the first and second connecting rods coincide with the central axis of the squid tentacle unit cell structure. The accompanying drawings only show examples where the first and second connecting rods are regular quadrilaterals. In fact, the first and second connecting rods can also be other regular polygons, such as regular pentagons or regular hexagons. Similarly, the first and second connecting rods can also be ring-shaped. In this case, in order to achieve the connection of the two-link system to form a squid tentacle-shaped cross-section, the present invention can set corresponding connection points on the first and second connecting rods to connect with the respective endpoints of the two-link system.

[0047] In this invention, the intermediate connecting rod is a parabolic rod, and the geometry of the parabolic rod satisfies:

[0048]

[0049] Where a is the side length of the upper or lower connecting rod; θ is the angle formed by the parabolic rod and the plane containing the upper and lower connecting rods; x and y represent the coordinates of any point on the parabolic rod.

[0050] The squid tentacle-like unit cell structure described in this invention is obtained through the following steps:

[0051] Step 1: First, connect the two ends of a parabolic rod to the endpoints of the first connecting rod and the second connecting rod respectively. Then, perform a planar symmetry transformation on the parabolic rod along the xoz plane where the central axis of the imitation squid tentacle unit cell structure is located, thereby forming a squid tentacle-shaped cross section with squid tentacle cross section characteristics.

[0052] Step 2: Rotate the cuttlefish tentacle-shaped feature cross-sections obtained in Step 1 around the central axis of the simulated cuttlefish tentacle unit cell structure. Then, connect the first connecting rods of two adjacent cuttlefish tentacle-shaped feature cross-sections to form a first connecting rod, and connect the second connecting rods to form a second connecting rod, thus obtaining the final simulated cuttlefish tentacle unit cell structure.

[0053] The squid-tentacle-like unit cell structures are periodically arrayed along their length. Between two adjacent squid-tentacle-like unit cell structures, one is designated as the first squid-tentacle-like unit cell structure and the other as the second squid-tentacle-like unit cell structure. The first connecting rod of the first squid-tentacle-like unit cell structure can be connected and fused with the second connecting rod of the second squid-tentacle-like unit cell structure to form a single unit. Referring to the attached figures, since the squid-tentacle-like unit cell structures are periodically arrayed along the z-axis, for ease of description, the upper squid-tentacle-like unit cell structure is designated as the first squid-tentacle-like unit cell structure, and the lower squid-tentacle-like unit cell structure is designated as the second squid-tentacle-like unit cell structure.

[0054] Some preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0055] Example 1

[0056] The laser additive manufacturing continuum robot mimicking squid tentacles described in this embodiment includes a squid tentacle-like single-cell structure, such as... Figure 1-3 As shown, the squid tentacle-like unit cell structure includes an upper connecting rod (i.e., the first connecting rod mentioned above), a lower connecting rod (i.e., the second connecting rod mentioned above), and a parabolic rod system 3; wherein:

[0057] The upper and lower connecting rods are parallel to each other and have the same geometric shape and dimensions. In the attached diagram, the upper and lower connecting rods are both regular quadrilaterals with a side length 'a' of 5 mm and a diameter 'd1' of 0.5 mm. The vertical centerlines of both the upper and lower connecting rods coincide with the central axis of the simulated squid tentacle unit cell structure.

[0058] The parabolic rod system comprises several parabolic rods. The two ends of each parabolic rod are respectively connected to pre-set connection nodes on the upper and lower connecting rods. In the attached diagram, since both the upper and lower connecting rods are regular quadrilaterals, each vertex of the upper and lower connecting rods is a pre-set connection node on the upper and lower connecting rods. Furthermore, the plane containing each parabolic rod has no common point with the central axis of the squid tentacle-like unit cell structure. Simultaneously, the plane containing each parabolic rod forms an angle θ of 30° with the plane containing the upper and lower connecting rods. In the attached diagram, the parabolic rod system comprises eight parabolic rods, with each pair of parabolic rods forming a group, connected at the middle position to form a vertically symmetrical bi-link system about the connection point. The upper end of each two-bar linkage is connected to two pre-set connection nodes on the upper connecting rod. The part of the upper connecting rod between these two connection points is called the first connecting support rod. The lower end of each two-bar linkage is connected to two pre-set connection nodes on the lower connecting rod. The part of the lower connecting rod between these two connection points is called the second connecting support rod.

[0059] The geometry of the parabolic rod is an abstract representation of the key geometric configuration based on the natural structural features of the cuttlefish tentacle cross-section. In the attached diagram, the geometry of the parabolic rod satisfies the following:

[0060]

[0061] Where a is the side length of the upper or lower connecting rod; θ is the angle formed by the parabolic rod and the plane containing the upper and lower connecting rods; x and y represent the coordinates of any point on the parabolic rod.

[0062] In this embodiment, a = 5mm, θ = 30°, therefore, the geometry of the parabolic rod satisfies: The diameter d2 of the parabolic rod is 0.5 mm.

[0063] The aforementioned squid tentacle-like unit cell structures are periodically arrayed along the z-axis and then interconnected to obtain a laser additive manufacturing squid tentacle-like continuum robot, such as... Figure 4-6 The illustration shows a specific embodiment of the laser additive manufacturing of a squid tentacle-like continuum robot according to the present invention, which includes twelve squid tentacle-like unit cell structures interconnected along the z-axis. Alternatively, the squid tentacle-like unit cell structure of the present invention may have only eleven, or thirteen, fourteen, or more.

[0064] When the aforementioned squid tentacle-like unit cell structures are periodically arrayed along the z-axis, the upper squid tentacle-like unit cell structure is designated as the upper squid tentacle-like unit cell structure, and the lower squid tentacle-like unit cell structure as the lower squid tentacle-like unit cell structure. The lower connecting rod of the upper squid tentacle-like unit cell structure and the upper connecting rod of its adjacent lower squid tentacle-like unit cell structure can be connected and fused together to form a single unit.

[0065] The method for constructing a laser additive manufacturing continuum robot resembling a squid tentacle is as follows: Using spherical nickel-titanium shape memory alloy pre-alloyed powder with a diameter not exceeding 60 μm as raw material, the continuum robot is fabricated using laser powder bed fusion additive manufacturing technology. The processing parameters are: laser power of 125 W, scanning speed of 1200 mm / s, scanning spacing of 50 μm, powder layer thickness of 90 μm, and spot diameter of 70 μm. The initial morphology of the laser additive manufacturing continuum robot after forming is shown in the figure below. Figure 7 As shown.

[0066] The individual squid tentacle-like unit cells of the obtained laser additive-manufactured squid tentacle-like continuum robot were first heated to 40°C and held for 4 minutes. Then, based on the desired motion posture and trajectory of the laser additive-manufactured squid tentacle-like continuum robot, the load application points for each squid tentacle-like unit cell were selected. In the attached figure, the selected load application points are the midpoints of the upper and lower connecting rods of any squid tentacle-shaped characteristic section of each unit cell. Each squid tentacle-like unit cell was individually loaded, specifically: dynamic compression was applied along a direction parallel to the central axis of the unit cell until the two load application points came into contact, and then the pressure was held for 20 seconds. Finally, each squid tentacle-like unit cell under pressure was cooled to -50°C and held for 3 minutes. This process was repeated 10 times to obtain the final laser additive-manufactured squid tentacle-like continuum robot with entanglement and capture functions. Figure 8 As shown.

[0067] The laser-additively manufactured squid tentacle-like continuum robot prepared in this embodiment exhibits coiling and entanglement behavior after the ambient temperature drops below 13°C. This behavior can be used for space target capture, significantly simplifying traditional continuum robot capture systems. The DSC curve of the matrix material of the laser-additively manufactured squid tentacle-like continuum robot is shown below. Figure 9 As shown.

[0068] Figure 11is the influence of different bionic cuttlefish tentacle unit structures on the winding and grasping function in the laser additive manufactured bionic cuttlefish tentacle continuum robot of the present invention. First, the present invention uses the bending angle α to evaluate the winding and grasping function of the laser additive manufactured bionic cuttlefish tentacle continuum robot of the present invention, and it is considered that a larger bending angle α indicates that the laser additive manufactured bionic cuttlefish tentacle continuum robot has a better winding and grasping function. The bending angle α specifically refers to the angle formed at any part of the laser additive manufactured bionic cuttlefish tentacle continuum robot when bending deformation occurs at that part.

[0069] It can be seen from the figure that: in the bionic cuttlefish tentacle unit structure constituting the continuum robot, when the side length a of the first connecting strut or the second connecting strut is 3 mm, and the included angle θ formed by connecting the parabolic rod to the plane where the first and second connecting struts are located is 30°, the bending angle α of the formed continuum robot is 77.16°, with reference to the accompanying Figure 11 of (a).

[0070] In the bionic cuttlefish tentacle unit structure constituting the continuum robot, when the side length a of the first connecting strut or the second connecting strut is 5 mm, and the included angle θ formed by connecting the parabolic rod to the plane where the first and second connecting struts are located is 30°, the bending angle α of the formed continuum robot is 99.64°, with reference to the accompanying Figure 11 of (b).

[0071] In the bionic cuttlefish tentacle unit structure constituting the continuum robot, when the side length a of the first connecting strut or the second connecting strut is 7 mm, and the included angle θ formed by connecting the parabolic rod to the plane where the first and second connecting struts are located is 30°, the bending angle α of the formed continuum robot is 69.75°, with reference to the accompanying Figure 11 of (c).

[0072] In the bionic cuttlefish tentacle unit structure constituting the continuum robot, when the side length a of the first connecting strut or the second connecting strut is 5 mm, and the included angle θ formed by connecting the parabolic rod to the plane where the first and second connecting struts are located is 15°, the bending angle α of the formed continuum robot is 85.43°, with reference to the accompanying Figure 11 of (d).

[0073] In the bionic cuttlefish tentacle unit structure constituting the continuum robot, when the side length a of the first connecting strut or the second connecting strut is 5 mm, and the included angle θ formed by connecting the parabolic rod to the plane where the first and second connecting struts are located is 45°, the bending angle α of the formed continuum robot is 65.54°, with reference to the accompanying Figure 11 of (e).

[0074] The data above shows that the bending angle α of the laser additive manufacturing continuum robot resembling a squid tentacle exhibits significant variations under different unit cell structural parameters, indicating that the continuum robot possesses high adjustability and optimization potential in its entangling and grasping function. In particular, when adjusting the side length 'a' of the first or second connecting rod and the angle θ formed by the parabolic rod connecting to the plane containing the first and second connecting rods, the variation range of the bending angle α increases significantly. This indicates that the continuum robot is highly sensitive to different parameter configurations. This sensitivity means that by finely adjusting key structural parameters, a better parameter combination can be explored, thereby further improving the robot's entangling and grasping function.

[0075] Based on these results, in the squid tentacle-like unit cell structure described in this invention, when a = 3mm-7mm and θ = 15°-45°, the continuous robot formed under the same process conditions exhibits excellent entanglement and grasping capabilities. When a = 3mm-5mm and θ = 15°-30°, the entanglement and grasping capabilities of the continuous robot formed under the same process conditions are further improved. And when a = 5mm and θ = 30°, the entanglement and grasping capabilities of the continuous robot formed under the same process conditions are further optimized.

[0076] Therefore, the laser additive manufacturing squid tentacle continuum robot described in this invention has extremely high design freedom and structural control potential, which can provide stronger grasping ability and more flexible operation adaptability for future practical applications, and has good scalability and application prospects.

[0077] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A laser additive manufacturing continuum robot resembling squid tentacles, comprising a continuum robot body, characterized in that, The continuum robot body comprises several squid tentacle-like unit cell structures; each squid tentacle-like unit cell structure is formed by periodically arranging and connecting with each other along the length extension direction by melting shape memory alloy powder using laser additive manufacturing technology. The simulated squid tentacle unit cell structure comprises several squid tentacle-shaped feature sections evenly distributed around its own central axis, and the squid tentacle-shaped feature sections are imitation components of natural squid tentacle sections. In the aforementioned squid tentacle-like unit cell structure, each squid tentacle-shaped cross section includes a first connecting rod, a second connecting rod, and two intermediate connecting rods arranged between the first and second connecting rods. The two intermediate connecting rods are arc-shaped rods with the same geometric shape; the two intermediate connecting rods are connected at the middle position and form a two-link system that is vertically symmetrical about the connection point; each end of the two-link system is connected to the end of the first and second connecting rods respectively, and forms an angle θ with the plane where the first and second connecting rods are located, and the plane where the two-link system is located is offset from the central axis of the imitation squid tentacle unit cell structure; The first connecting rods of each cuttlefish tentacle-shaped cross section can be directly spliced ​​or transitionally connected to each other to form a first connecting rod, and the second connecting rods of each cuttlefish tentacle-shaped cross section can be directly spliced ​​or transitionally connected to each other to form a second connecting rod. The first and second connecting rods are parallel to each other and have the same geometric shape, both being regular polygons or rings. The vertical center lines of the first and second connecting rods coincide with the central axis of the squid tentacle unit cell structure, while the middle connecting rod is a parabolic rod.

2. The laser additive manufacturing continuum robot resembling a squid tentacle as described in claim 1, characterized in that, The first and second connecting rods are square in shape, and the parabolic rod has the following geometry: ； in, θ is the side length of the first or second connecting rod; θ is the angle formed by the parabolic rod and the plane containing the first and second connecting rods. , This represents the coordinates of any point on the parabolic rod.

3. The laser additive manufacturing continuum robot resembling a squid tentacle as described in claim 2, characterized in that, The design steps for the squid tentacle-like single-cell structure are as follows: Step 1: First, connect the two ends of a parabolic rod to the endpoints of the first connecting rod and the second connecting rod respectively. Then, perform a planar symmetry transformation on the parabolic rod along the xoz plane where the central axis of the imitation squid tentacle unit cell structure is located, thereby forming a squid tentacle-shaped cross section with squid tentacle cross section characteristics. Step 2: Rotate the cuttlefish tentacle-shaped feature cross-sections obtained in Step 1 around the central axis of the simulated cuttlefish tentacle unit cell structure. Then, connect the first connecting rods of two adjacent cuttlefish tentacle-shaped feature cross-sections to form a first connecting rod, and connect the second connecting rods to form a second connecting rod, thus obtaining the final simulated cuttlefish tentacle unit cell structure.

4. The laser additive manufacturing continuum robot resembling a squid tentacle as described in claim 1, characterized in that, After the squid tentacles are periodically arrayed along their own length, between two adjacent squid tentacles, one is designated as the first squid tentacles and the other as the second squid tentacles. The first connecting rod of the first squid tentacles can be connected and fused with the second connecting rod of the second squid tentacles to form a whole.

5. A method for constructing a laser additive manufacturing continuum robot resembling a squid tentacle, according to any one of claims 1-4, characterized in that: Using spherical nickel-titanium shape memory alloy pre-alloyed powder with a diameter not exceeding 60 μm as raw material, a squid tentacle continuum robot was prepared by laser powder bed melting additive manufacturing technology. Processing parameters: laser power is 125 W, scanning speed is 1200 mm / s, scanning distance is 50 μm, powder layer thickness is 90 μm, and spot diameter is 70 μm; The obtained squid tentacle-like continuum robot was trained to exhibit coiling and winding behavior, resulting in a final laser additive manufacturing squid tentacle-like continuum robot with capture capabilities.

6. The method for constructing a laser additive manufacturing continuum robot resembling a squid tentacle as described in claim 5, characterized in that, The object of the curling and winding behavior training is the individual squid tentacle unit cell structures that make up the laser additive manufacturing squid tentacle continuum robot. The training process includes the following sequential steps: heating-loading-cooling-unloading, wherein: Heating process: Heat each imitation squid tentacle unit cell structure to above the austenite phase transformation temperature and below the stress-induced martensite phase transformation maximum temperature, and hold for 3-5 minutes. Loading process: Each squid tentacle unit cell structure is individually loaded. Specifically, based on the required motion posture and trajectory of the laser additive manufacturing squid tentacle continuum robot, one or more load application points are selected on the first and second connecting rods of each squid tentacle unit cell structure. The load application points on the first connecting rod and the load application points on the second connecting rod are set one-to-one. Then, a load is applied to each squid tentacle unit cell structure individually so that the corresponding squid tentacle unit cell structure can be dynamically compressed along the direction parallel to the central axis of the squid tentacle unit cell structure until the load application point on the first connecting rod of the squid tentacle unit cell structure can contact the corresponding load application point on the second connecting rod and then hold the pressure for 15-30 seconds. Cooling process: Cool each squid tentacle-like unit cell structure under pressure to below the martensitic phase transformation temperature and hold for 3-5 minutes. By repeating the above training process 10-30 times on each of the squid tentacle-like unit cell structures to train the curling and winding behavior, the final laser additive manufacturing squid tentacle-like continuum robot with capture function can be obtained.

7. The method for constructing a laser additive manufacturing continuum robot resembling a squid tentacle as described in claim 6, characterized in that, During the loading process, the specific steps for selecting the load application point on the first and second connecting rods of each squid tentacle unit cell structure are as follows: For each squid tentacle unit cell structure, firstly, select a point on the first connecting rod of any squid tentacle-shaped characteristic section as the load application point, and then select a point on the second connecting rod of the same squid tentacle-shaped characteristic section that corresponds to the load application point on the first connecting rod as the load application point on the second connecting rod.

8. An application of the laser additive manufacturing of a squid tentacle-like continuum robot according to claim 1 in the aerospace field, characterized in that, The laser-additively manufactured squid tentacle-like continuum robot can be used for space target capture.

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