A rigid-flexible coupled continuum robot unit and a continuum robot

Abstract

Disclosed are a rigid-flexible coupling continuum robot unit and a continuum robot. In the rigid-flexible coupling continuum robot unit, structural unit blocks are connected to each other in an interlaced manner to form a whole mechanical arm; a flexible nickel-titanium rod is connected to two adjacent structural unit blocks at two ends, respectively; a front-end unit block is arranged at the frontmost end of the mechanical arm; and a rear-end unit block is arranged at the rearmost end of the mechanical arm. In use, the memory alloy nickel-titanium rod forms a flexible joint, a limiting clamping jaw and a limiting boss form a rigid joint, the two joints complement each other, after a driving wire exerts a pressure, the limiting clamping jaw and the limiting boss are in a wrapping relationship, the movement track of the robot unit is limited, the robot unit always rotates along a circular arc around a rotation center, and the robot unit has the advantages of simple and accurate kinematic modeling, strong torsion resistance, strong load bearing capacity and the like, and is suitable for operation in various complex environments.

Description

Technical Field

[0001] This invention relates to the field of continuous robot technology, and in particular to a rigid-flexible coupled continuous robot unit and a continuous robot. Background Technology

[0002] Continuum robots, as a unique type of robot, have attracted widespread attention. Compared with traditional rigid robots, continuum robots possess a flexible structure, enabling them to bend, curl, and extend, thus adapting to different working environments and tasks. Simultaneously, continuum robots have multiple degrees of freedom, allowing them to deform flexibly in three-dimensional space, thereby achieving more complex operations and movements. Due to their flexibility, continuum robots can perform operations in confined or complex spaces and adapt to working environments with different shapes and surfaces, such as medical surgery, rescue and search, and aircraft engine maintenance, demonstrating broad application potential.

[0003] The structural design of a continuum robot directly affects its performance. Many different structural solutions have been proposed, but some problems remain. Traditional dual-core continuum robots, such as the structure used in the invention patent "A Line-Driven Continuum Robot" (Publication No. CN 111168658 A), exhibit complex spline curve motion deformation and are prone to torsional deformation, making them unable to withstand large loads. Some contact-assisted continuum robot structures, such as the invention patent "A Cam-Assisted Flexible Continuum Robot Unit and Robot" (Publication No. CN 113814966 A), use a cam mechanism in the middle and two spring plates on both sides. However, the main purpose of this cam mechanism is to limit the joint motion trajectory; for torsional loads, the force point is close to the center, the lever arm is short, and the torsional resistance is limited. Another example is "A Flexible Joint Based on Rolling Contact and a Continuum Robot Having It" (Publication No. CN 110900651). A) It sets a spring plate in the middle and rolling body mechanisms on both sides. The rolling body structure has no contact limit in the circumferential direction of the torsion, so the torsional resistance is also limited. In addition, the torsional resistance provided by the spring plate in the above two schemes is not great, and the space in the middle of the continuous robot arm is occupied, and through holes cannot be set to arrange operating equipment, such as cables, cameras, searchlights, grinders, scalpels, etc., which undoubtedly greatly weakens the functionality of the continuous robot.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a rigid-flexible coupled continuum robot unit and a continuum robot. The gripper structure and boss structure provide contact and limiting, exhibiting strong torsional resistance and load-bearing capacity. Furthermore, it offers advantages such as simple and accurate kinematic modeling and a through-hole in the middle for arranging operating instruments, enabling it to better adapt to different environments for operation.

[0006] The objective of this invention is achieved through the following technical solution. The rigid-flexible coupled continuum robot unit includes:

[0007] Multiple structural unit blocks, connected in series, form a robotic arm. The structural unit blocks include...

[0008] The unit body includes a central operating hole extending along the central axis and flexible rod hole slots and drive line through holes located on the periphery.

[0009] The limiting claw extends downward from the lower surface of the unit body.

[0010] A limiting boss extends upward from the upper surface of the unit body, and the limiting boss engages with and limits the limiting claw of the unit body of another adjacent structural unit block above it.

[0011] Multiple side grooves are recessed inward from the side surface of the unit body in a direction perpendicular to the central axis.

[0012] Multiple set screw holes are provided on the side surface of the unit body and communicate with the flexible rod hole slot, and the set screw holes and the side slot are arranged alternately.

[0013] A front-end unit block, which is arranged at the very front end of the robotic arm, includes,

[0014] The unit body includes a central threaded hole extending along the central axis, a flexible rod slot and a drive line through hole located on the periphery.

[0015] A limiting claw extends downward from the lower surface of the unit body of the front unit block, and engages with the limiting boss of the adjacent structural unit block below for positioning.

[0016] Multiple side grooves are recessed inward from the side surface of the unit body of the front unit block in a direction perpendicular to the central axis.

[0017] Multiple set screw holes are provided on the side surface of the unit body of the front unit block and communicate with the flexible rod hole slot. The set screw holes and the side slot are arranged alternately. The flexible nickel-titanium rod passes through the flexible rod hole slot of the front unit block and is connected via the set screw in the set screw hole.

[0018] A rear-end unit block, disposed at the rearmost end of the robotic arm, includes...

[0019] The unit body includes a central operating hole extending along the central axis and flexible rod hole slots and drive line through holes located on the periphery.

[0020] A limiting boss extends upward from the upper surface of the unit body of the rear unit block, and the limiting boss engages with the limiting claw of the adjacent structural unit block above for positioning.

[0021] Multiple side grooves are recessed inward from the side surface of the unit body of the rear unit block in a direction perpendicular to the central axis.

[0022] Multiple set screw holes are provided on the side surface of the unit body of the rear unit block and communicate with the flexible rod slot. The set screw holes and the side slot are arranged alternately. The flexible nickel-titanium rod passes through the flexible rod slot of the rear unit block and is connected via set screws in the set screw holes.

[0023] A connecting chassis is located at the bottom of the unit body of the rear unit block, and a plurality of second settling thread holes are distributed around the periphery of the connecting chassis;

[0024] Multiple flexible nickel-titanium rods pass through flexible rod slots in the unit body and are connected via set screws in the set screw holes.

[0025] In the aforementioned rigid-flexible coupled continuum robot unit, the unit body is a cylindrical structure.

[0026] In the aforementioned rigid-flexible coupled continuum robot unit, the front-end unit block is threadedly connected to the operating instrument via a central threaded hole.

[0027] In the aforementioned rigid-flexible coupled continuum robot unit, the operating instruments include cameras, searchlights, grinders, or scalpels, etc.

[0028] In the aforementioned rigid-flexible coupled continuum robot unit, the rear unit block is fixedly connected to the drive control system via a second set screw hole.

[0029] In the rigid-flexible coupling continuum robot unit, the limiting claw is engaged in the square groove of the limiting boss. In two adjacent structural unit blocks, the inner arc surface of the limiting claw and the outer arc surface of the limiting boss are tangent to each other in a clearance fit.

[0030] In the rigid-flexible coupling continuum robot unit, there are two limiting claws and two limiting bosses, which are set on both sides of the central operating hole and are staggered by 90° along the axial direction in the same structural unit block.

[0031] In the rigid-flexible coupled continuum robot unit, two adjacent structural unit blocks form a joint, each joint has one degree of freedom, and several structural unit blocks are arranged in a staggered manner along the axial direction at 90° to form a multi-degree-of-freedom bending and turning mechanism.

[0032] In the aforementioned rigid-flexible coupled continuum robot unit, the front-end unit block, structural unit block, and rear-end unit block are connected in series on the same curved central axis.

[0033] A continuum robot includes the aforementioned rigid-flexible coupled continuum robot unit, wherein multiple drive lines sequentially pass through drive line through holes in a front-end unit block, a structural unit block, and a rear-end unit block to form a continuum robot.

[0034] Compared with the prior art, the advantages of the present invention are:

[0035] 1. This invention adopts a rigid-flexible coupling structure and uses a shape memory metal nickel-titanium rod as a skeleton support, which improves flexibility and flexibility; it adopts a contact-assisted method, in which the claws and bosses of each robot unit are interlocked and wrapped around each other to form a rigid connection joint.

[0036] 2. The present invention also has anti-torsion capability. Due to the rigid connection method, when torsion occurs, the claw and the boss limit each other, thereby greatly improving its anti-torsion capability.

[0037] 3. The present invention also has a definite motion trajectory. Due to the rigid connection method, the motion trajectory of the robot unit can be restricted, so that it always rotates around the center of rotation along an arc. Its kinematic modeling is simple and accurate.

[0038] 4. The present invention also has the maximum bending angle to prevent overload damage. Due to the contact-assisted method, when adjacent units bend, the end of the claw and the root of the boss contact each other to form the maximum bending angle, thereby preventing excessive load from damaging the flexible joint, and also improving the load-bearing capacity.

[0039] 5. The present invention also includes a through hole in the middle for arranging operating instruments, such as cables, cameras, searchlights, grinders, scalpels, etc., which can better adapt to different environments for operation.

[0040] 6. The present invention also has a side groove at the position where the wire passes through the side of the unit block, which can reduce the contact between the drive line and the block, thereby reducing the negative impact of friction.

[0041] The above description is merely an overview of the technical solution of the present invention. In order to make the technical means of the present invention clearer and more understandable, so that those skilled in the art can implement it according to the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more obvious and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0042] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0043] In the attached diagram:

[0044] Figure 1 This is a schematic diagram of the rigid-flexible coupling continuum robot unit and the continuum robot of the present invention;

[0045] Figure 2 This is a schematic diagram of the structural unit block in this invention;

[0046] Figure 3 This is a schematic diagram of the front-end unit block in this invention;

[0047] Figure 4 This is a schematic diagram of the structure of the back-end unit block in this invention;

[0048] Figure 5 This is a schematic diagram of the deformed continuum robot of the present invention.

[0049] The present invention will be further explained below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0050] Specific embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While specific embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0051] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions are preferred embodiments for carrying out the invention; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of the invention. The scope of protection of this invention is determined by the appended claims.

[0052] To facilitate understanding of the embodiments of the present invention, further explanations and descriptions will be provided below with reference to the accompanying drawings and specific embodiments. The accompanying drawings do not constitute a limitation on the embodiments of the present invention.

[0053] To better understand, such as Figures 1 to 5 As shown, a rigid-flexible coupled continuum robot unit includes structural unit blocks 1, which serve as the main structural units of the robotic arm and are interconnected to form the entire robotic arm; flexible nickel-titanium rods 2, whose two ends are respectively connected to two adjacent structural unit blocks 1, and are connected by set screws in flexible rod slots 12 and set screws in set screw holes 16; front unit block 3, which is arranged at the front end of the robotic arm; and rear unit block 4, which is arranged at the rear end of the robotic arm.

[0054] like Figure 2 As shown, the structural unit block 1 includes a central operating hole 11, a flexible rod hole groove 12, a limiting claw 13, a limiting boss 14, a drive wire through hole 15, a set thread hole 16, and a side groove 17. The limiting claw 13 is disposed on the lower surface of the structural unit block 1; the limiting boss 14 is disposed on the upper surface of the structural unit block 1. The limiting claw 13 has a square groove and can be engaged with the boss of the limiting boss 14. In two adjacent structural unit blocks 1, the inner arc surface of the limiting claw 13 and the outer arc surface of the limiting boss 14 are tangent to each other and form an enclosing relationship. Furthermore, it is a clearance fit; there are two of each of the limiting claws 13 and limiting bosses 14, which are arranged on both sides of the central operating hole 11 and are staggered at 90° along the axial direction in the same structural unit block 1; the central operating hole 11 is a through hole, which is located at the center of the structural unit block 1; the drive line through hole 15 is arranged around the central operating hole 11 and penetrates the structural unit block 1; the set thread hole 16 and the side groove 17 are staggered on the side surface of the structural unit block 1, and the side groove 17 can reduce the contact between the drive line and the block, thereby reducing the impact of friction.

[0055] like Figure 3As shown, the front-end unit block 3 includes a central threaded hole 31, a flexible rod hole groove 12, a limiting claw 13, a drive line through hole 15, a set threaded hole 16, and a side groove 17. The central threaded hole 31 is located at the center of the front-end unit block 3 and is arranged at the front end of the robotic arm. It can be connected to operating instruments such as cameras, searchlights, grinders, and scalpels.

[0056] like Figure 4 As shown, the rear unit block 4 includes a connecting chassis 41, a second set screw hole 42, a central operating hole 11, a flexible rod hole groove 12, a limiting boss 14, a drive line through hole 15, a set screw hole 16, and a side groove 17. The rear unit block 4 is arranged at the rear end of the robotic arm. The connecting chassis 41 is provided with four second set screw holes 42, which can connect and fix the robotic arm and the drive control system.

[0057] like Figure 5 As shown, when the rigid-flexible coupled continuum robot unit is working, the force applied by the drive line causes the robot structural unit block 1 to rotate under pressure, and the flexible nickel-titanium rod 2 to deform under pressure, which is a state in which the entire robotic arm bends.

[0058] In one embodiment, the rigid-flexible coupled continuum robot unit includes structural unit block 1, flexible nickel-titanium rod 2, front unit block 3, and rear unit block 4. Each pair of adjacent unit blocks forms a joint, and each joint has one degree of freedom. Several structural unit blocks 1 are arranged alternately at 90° along the axial direction to form a multi-degree-of-freedom bending and turning mechanism. Multiple drive lines pass through drive line through holes 15 in sequence. When the drive lines are pulled, each unit block is compressed, and the entire continuum robot arm bends and deforms. The flexible part, the flexible nickel-titanium rod 2, deforms under pressure. It is a shape memory alloy and has excellent springback ability. The rigid part, the inner arc surface of the limiting claw 13 and the outer arc surface of the limiting boss 14 are correspondingly tangent and have a wrapping relationship. They are also clearance fits, which can limit the movement trajectory of the robot unit, making it always rotate around the center of rotation along an arc, making its kinematic modeling simpler and more accurate. The rigid and flexible parts complement each other to form a rigid-flexible coupled mechanism.

[0059] The limiting claw 13 has a square groove that can be locked onto the boss of the limiting boss 14. When torsion occurs, the claw and the boss mutually limit each other, thereby greatly improving its torsion resistance. At the same time, when adjacent units bend, the end of the claw and the root of the boss contact each other to form the maximum bending angle, thereby preventing excessive load from damaging the flexible joint and improving the load-bearing capacity.

[0060] The robotic arm can bend and deform in different working environments according to the needs of the task objectives, thereby forming the required shape. Then, according to the task requirements, the necessary tools, such as cameras, searchlights, grinders, scalpels, and other instruments, as well as cables that supply power or transmit signals, are arranged in the central operating hole 11 to complete the task objectives.

[0061] In one embodiment, the rigid-flexible coupled continuum robot unit and the continuum robot include:

[0062] Structural unit block 1, which is interconnected to form the entire robotic arm;

[0063] A flexible nickel-titanium rod 2, with its two ends connected to two adjacent structural unit blocks 1 respectively;

[0064] Front unit block 3 is located at the very front of the robotic arm;

[0065] Rear unit block 4 is located at the rear end of the robotic arm.

[0066] The structural unit block 1 includes a central operating hole 11, a flexible rod slot 12, a limiting claw 13, a limiting boss 14, a drive line through hole 15, a set screw hole 16, and a side slot 17. The limiting claw 13 is disposed on the lower surface of the structural unit block 1; the limiting boss 14 is disposed on the upper surface of the structural unit block 1; the central operating hole 11 is a through hole located at the center of the structural unit block 1; the drive line through hole 15 is disposed around the central operating hole 11 and penetrates the structural unit block 1; the set screw hole 16 and the side slot 17 are alternately disposed on the side surface of the structural unit block 1. The flexible nickel-titanium rod 2 is disposed between two adjacent structural unit blocks 1 and connected by a set screw in the flexible rod slot 12 and the set screw in the set screw hole 16. The front-end unit block 3 includes a central threaded hole 31, a flexible rod slot 12, a limiting claw 13, a drive line through hole 15, a set threaded hole 16, and a side groove 17. The central threaded hole 31 is located at the center of the front-end unit block 3 and at the foremost end of the robotic arm, allowing connection to instruments such as cameras, searchlights, grinders, and scalpels. The rear-end unit block 4 includes a connecting base 41, a second set threaded hole 42, a central operating hole 11, a flexible rod slot 12, a limiting boss 14, a drive line through hole 15, a set threaded hole 16, and a side groove 17. The rear-end unit block 4 is located at the rear end of the robotic arm, and the connecting base 41 has four second set threaded holes 42 for connecting and fixing the robotic arm and the drive control system. The limiting claw 13 has a square groove and can be engaged with the protrusion of the limiting boss 14. In two adjacent structural unit blocks 1, the inner arc surface of the limiting claw 13 and the outer arc surface of the limiting boss 14 are correspondingly tangent, forming an enclosing relationship and a clearance fit. There are two limiting claws 13 and two limiting bosses 14, which are arranged on both sides of the central operating hole 11 and are staggered by 90° along the axial direction in the same structural unit block 1. Each pair of adjacent unit blocks forms a joint, and each joint has one degree of freedom. Several structural unit blocks 1 are arranged staggered by 90° along the axial direction to form a multi-degree-of-freedom bending and turning mechanism. Multiple drive lines pass through the drive line through holes 15 in sequence and are connected to form a continuous robot.

[0067] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not restrict the application from being implemented using the specific details described above.

[0068] The above description has been provided for illustrative and descriptive purposes. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although several embodiments have been discussed above, those skilled in the art will recognize, through the teachings of this specification and without departing from the scope of the claims, various variations, modifications, additions, and sub-combinations thereof, all of which fall within the scope of protection of this invention.

Claims

1. A rigid-flexible coupled continuum robot unit, characterized in that, It includes, Multiple structural unit blocks, connected in series, form a robotic arm. The structural unit blocks include... The first unit body includes a central operating hole extending along the central axis, a first flexible rod hole groove and a first drive line through hole located on the periphery. The first limiting claw extends downward from the lower surface of the first unit body. A first limiting protrusion extends upward from the upper surface of the first unit body, and the first limiting protrusion engages with and limits the first limiting claw of the first unit body of another adjacent structural unit block above it. Multiple first side grooves are recessed inward from the side surface of the first unit body in a direction perpendicular to the central axis. Multiple first set screw holes are provided on the side surface of the first unit body and connected to the first flexible rod hole groove. The first set screw holes and the first side groove are arranged alternately. A front-end unit block, which is arranged at the very front end of the robotic arm, includes, The second unit body includes a central threaded hole extending along the central axis and a second flexible rod hole groove and a second drive line through hole located on the periphery. The second limiting claw extends downward from the lower surface of the second unit body of the front unit block, and engages with the first limiting boss of the adjacent structural unit block below for positioning. Multiple second side grooves are recessed inward from the side surface of the second unit body of the front end unit block in a direction perpendicular to the central axis. Multiple second set screw holes are provided on the side surface of the second unit body of the front end unit block and communicate with the second flexible rod hole slot. The second set screw holes and the side slot are arranged alternately. The flexible nickel-titanium rod passes through the second flexible rod hole slot of the front end unit block and is connected via the set screw in the second set screw hole. A rear-end unit block, disposed at the rearmost end of the robotic arm, includes... The third unit body includes a central operating hole extending along the central axis, a third flexible rod hole groove and a third drive line through hole located on the periphery. The second limiting boss extends upward from the upper surface of the third unit body of the rear unit block, and engages with the first limiting claw of the adjacent structural unit block above for positioning. Multiple third side grooves are recessed inward from the side surface of the third unit body of the rear unit block in a direction perpendicular to the central axis. Multiple third set screw holes are provided on the side surface of the third unit body of the rear unit block and communicate with the third flexible rod hole slot. The third set screw holes and the third side slot are arranged alternately. The flexible nickel-titanium rod passes through the third flexible rod hole slot of the rear unit block and is connected via a set screw in the third set screw hole. A connecting chassis is located at the bottom of the unit body of the rear unit block, and a plurality of fourth set screw holes are distributed around the periphery of the connecting chassis; Multiple flexible nickel-titanium rods pass through the first, second, and third flexible rod slots of the first, second, and third unit bodies and are connected via set screws in the first, second, and third set screw holes.

2. The rigid-flexible coupled continuum robot unit as described in claim 1, characterized in that, The first, second, and third units are cylindrical in structure.

3. The rigid-flexible coupled continuum robot unit as described in claim 1, characterized in that, The front unit block is threadedly connected to the operating instrument via the central threaded hole.

4. The rigid-flexible coupled continuum robot unit as described in claim 3, characterized in that, Operating instruments include cameras, searchlights, grinders, or scalpels.

5. The rigid-flexible coupled continuum robot unit as described in claim 1, characterized in that, The rear unit block is fixedly connected to the drive control system via the fourth set screw hole.

6. The rigid-flexible coupled continuum robot unit as described in claim 1, characterized in that, The limiting claw engages in the square groove of the adjacent limiting boss. In two adjacent structural unit blocks, the inner arc surface of the limiting claw and the outer arc surface of the limiting boss are tangent to each other for clearance fit.

7. The rigid-flexible coupled continuum robot unit as described in claim 1, characterized in that, The front-end unit block, structural unit block, and rear-end unit block are connected in series on the same curved central axis.

8. A continuum robot, characterized in that, It includes a rigid-flexible coupled continuum robot unit as described in any one of claims 1-7, wherein multiple drive lines pass through drive line through holes in a front unit block, a structural unit block, and a rear unit block in sequence to form a continuum robot.

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