Two-degree-of-freedom parallel mechanism bionic eye based on artificial muscle driving

Abstract

This invention belongs to the field of bionic robotics technology, specifically disclosing a bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles. It includes a two-degree-of-freedom flexible driving parallel mechanism with a bionic eye structure on it. The bionic eye structure includes a flexible eyeball. The two-degree-of-freedom flexible driving parallel mechanism includes symmetrically arranged rectus muscle flexible bodies and rectus muscle ties connected to the flexible eyeball. The end of the rectus muscle flexible body has a common tendon ring platform that cooperates with the rectus muscle ties. This invention, by using a ball-joint connected bionic eye structure, combined with the four artificial muscles of the rectus muscle flexible body in the two-degree-of-freedom flexible driving parallel mechanism, enables the bionic eye to possess two movement postures: yaw and pitch. By conforming to the physiological structure and main movement patterns of the human eyeball, and through the stepless adjustment of the rectus muscle flexible body by the rectus muscle ties, precise two-degree-of-freedom adjustment of the bionic eye can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of bionic robot technology, specifically relating to a bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles. Background Technology

[0002] The eye is a vital organ for human perception of the outside world. Its intricate structure and complex function make it one of the primary senses for communication, interaction, and perception, and a crucial means for acquiring information and understanding the world. With the development of science and technology and the deepening of human research on the eye, bionic eye technology has emerged and become an important research and application area in fields such as biomedical engineering, materials science, mechanical engineering, and electronic engineering. In the field of robotics, equipping robots with bionic eye devices can enhance their visual perception capabilities, enabling them to perceive the outside world in a way similar to humans.

[0003] The human eye has six extraocular muscles distributed around it, with the main eye movements—horizontal and pitch—controlled by four rectus muscles. Therefore, a bionic eye only needs two degrees of freedom to achieve the bionic function of mimicking the main movement mechanism of the human eye. Existing bionic eyes mostly use springs and links to simulate the movement of the rectus muscles. In actual simulation and adjustment, springs and links not only produce abnormal noise, but this noise cannot be avoided by existing methods. Furthermore, due to the limitations of springs and links in simulating the rectus muscles, the simulated rectus muscles cannot be precisely adjusted. This results in existing bionic eyes being noisy, having low movement flexibility, and being unable to achieve high-precision adjustment during use.

[0004] Chinese Patent CN110497389B discloses a rope-spring driven three-degree-of-freedom parallel bionic eye actuator, which mainly comprises a three-degree-of-freedom parallel mechanism and three rope drive branches. Each of the three branches of the three-degree-of-freedom parallel mechanism has three springs, ensuring that the moving platform is always subjected to forces in opposite directions of the rope tension. The three drive rods drive the moving platform through the ropes, achieving three-degree-of-freedom motion. A camera mounted on the moving platform can also achieve three-degree-of-freedom motion. This mechanism has the advantages of fewer drives, a compact structure, high speed, high rigidity, and high precision. However, this rope-spring driven three-degree-of-freedom parallel bionic eye actuator, while using ropes and springs, suffers from drawbacks such as high noise and low motion flexibility. Furthermore, it is difficult to achieve high-precision adjustment of the bionic eye through spring drive alone. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism that is compact, low-noise, highly flexible in motion, and highly precise in adjustment.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] A bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles includes a two-degree-of-freedom flexible driving parallel mechanism, on which a bionic eye structure is provided. The bionic eye structure includes a flexible eyeball. The two-degree-of-freedom flexible driving parallel mechanism includes a symmetrically arranged flexible rectus muscle body and a rectus muscle tether connected to the flexible eyeball body. The end of the flexible rectus muscle body is provided with a common tendon ring platform that cooperates with the rectus muscle tether.

[0008] Furthermore, an eyeball shell is fitted inside the flexible eyeball, and an internal boss is provided on the eyeball shell, which cooperates with a camera hole provided on the flexible eyeball; a camera connected to the internal boss is provided on the side of the flexible eyeball away from the rectus muscle flexible body; an eyeball support is provided inside the eyeball shell, which is in clearance fit with the inner wall surface of the eyeball shell; the flexible eyeball is fitted on the surface of the eyeball shell; the eyeball support is in clearance fit with the eyeball shell and is fixed by bolts.

[0009] Furthermore, one end of the rectus muscle flexible body is glued to the outer surface of the eyeball flexible body, and the other end is glued to the common tendon ring platform. The common tendon ring platform is provided with a platform groove that cooperates with the rectus muscle flexible body. The rectus muscle rope is set in the rectus muscle flexible body. One end of the rectus muscle flexible body is glued to the eyeball flexible body, and the other end is glued to the common tendon ring platform, while the rectus muscle rope passes through the middle.

[0010] Furthermore, the rectus muscle tether includes two adjustable tethers with a gap fit. One end of the adjustable tether is connected to an arc-shaped connecting piece located on the inner side of the ocular flexible body. The arc-shaped connecting piece is an arc-shaped iron plate. During installation, the arc-shaped iron plate is close to the inner side of the ocular flexible body, and the tether passes through the ocular flexible body, the rectus muscle flexible body, and the common tendon ring platform in sequence through the reserved hole. The reserved hole and the tether are gap-fitted.

[0011] Furthermore, the adjustment rope engages with the rectus muscle flexible body through a pre-drilled hole on the flexible eyeball; the flexible rectus muscle flexible body has through holes that respectively engage with the gaps of the adjustment rope.

[0012] Furthermore, the common tendon ring platform is provided with platform holes that mate with the gap of the adjusting rope, and the platform holes are set in the platform groove.

[0013] Furthermore, the through holes are symmetrically positioned in the middle of the rectus muscle flexible body along its longitudinal direction; the reserved holes are located at the connection between the ocular flexible body and the rectus muscle flexible body.

[0014] Furthermore, four rectus muscle flexible bodies are symmetrically arranged on the eyeball flexible body, with an included angle of 90° between adjacent rectus muscle flexible bodies; the inner side surface of the rectus muscle flexible bodies is distributed with gap-fitting hollow polygons, which are hexagonal hollows and triangular hollows, and the thickness of the remaining ribs between the hollow polygons is 3mm.

[0015] Furthermore, the camera lens is oriented in the same direction as the bionic eye's line of sight; the artificial muscles consist of a flexible eyeball, a flexible rectus muscle, and rectus muscle ligaments.

[0016] Furthermore, the bionic eye structure also includes a ball joint bracket mounted on the eyeball support; one side of the ball joint bracket has a ball joint that connects to the ball joint of the eyeball support, and the ball joint is connected to a ball joint hole located in the center of the eyeball support; the other side has a screw that corresponds one-to-one with the flexible rectus muscle, and the end of the screw away from the ball joint bracket is connected to the common tendon ring platform; the screw is a 5M screw; the bionic eye structure is connected to the ball joint by the eyeball support and fixed by nuts, and the ball joint is installed on the ball joint bracket by bolts; the adjusting rope is fitted with multiple adjusting balls that cooperate with the through holes, and the adjusting balls are fitted with adjusting rings that cooperate with the through holes; a micro spring is installed inside the hollow polygon, and the two ends of the micro spring are connected to the inner wall of the hollow polygon.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] (1) This invention uses a bionic eye structure connected by a ball joint, combined with four artificial muscles of the rectus muscle flexible body in a two-degree-of-freedom flexible drive parallel mechanism, so that the bionic eye has two movement postures: yaw and pitch. Thus, by conforming to the physiological structure and main movement form of the human eyeball, the bionic eye can achieve two-degree-of-freedom precise adjustment through the stepless adjustment of the rectus muscle flexible body by the rectus muscle rope. During the adjustment process, the rectus muscle flexible body can perfectly simulate the movement adjustment of the rectus muscle of the eye, and can achieve the purpose of high movement flexibility and low noise adjustment of the bionic eye.

[0019] (2) The present invention uses a silicone casting mold to make the soft body parts of the rectus muscle flexible body and the eyeball flexible body of the artificial muscle. The rectus muscle flexible body can perfectly imitate the superior rectus muscle, inferior rectus muscle, medial rectus muscle and lateral rectus muscle of the human eyeball, which facilitates the silent adjustment of the bionic eye. The rectus muscle flexible body has a hollow polygonal shape with a hollow center on the inner side, which not only facilitates the infinite stretching of the rectus muscle flexible body and realizes the high-precision adjustment of the bionic eye, but also greatly increases the service life of the bionic eye and reduces the generation of abnormal noise during use.

[0020] (3) The present invention uses a common tendon ring platform to imitate the common tendon ring in the structure of the human eyeball, which is used to control the extraocular muscles to perform contraction and extension movements, so that the bionic eye can achieve two degrees of freedom adjustment. The present invention imitates the structure of the human eyeball and uses two degrees of freedom artificial muscles to drive in a flexible parallel manner, which has the characteristics of compact structure, low noise and high movement flexibility.

[0021] (5) The present invention includes a bionic eye structure and a two-degree-of-freedom flexible drive parallel mechanism; the bionic eye structure consists of a camera, a flexible eyeball, an eyeball shell, and an eyeball support; the two-degree-of-freedom flexible drive parallel mechanism mainly consists of a common tendon ring platform, a flexible rectus muscle body, and a rectus muscle rope. The flexible eye muscle body is connected to the flexible rectus muscle body through the rectus muscle rope. The common tendon ring platform is connected to the ball joint support through a screw. The ball joint support is connected to the moving platform by installing a ball joint. The present invention achieves the two-degree-of-freedom motion adjustment capability of the bionic eye by the mutual cooperation between the flexible rectus muscle body, the rectus muscle rope, and the ball joint, and by stretching the rectus muscle rope, controlling the flexible rectus muscle body to perform the stretching and contraction movement to imitate the stretching and contraction of the extraocular muscles during human eyeball movement. At the same time, the stretching and contraction of the four flexible rectus muscles (upper, lower, left, and right) realize the two-degree-of-freedom motion adjustment capability of the bionic eye. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention in Embodiment 1;

[0023] Figure 2 This is a schematic diagram of the structure of the present invention in Embodiment 1;

[0024] Figure 3 This is the front view of the present invention in Embodiment 1;

[0025] Figure 4 This is a side view of the present invention in Embodiment 1;

[0026] Figure 5 This is a rear view of the present invention in Embodiment 1;

[0027] Figure 6 This is a schematic diagram of the connection between the ball joint support and the eyeball support in Embodiment 1 of the present invention;

[0028] Figure 7 This is a schematic diagram of the internal structure of the present invention in Embodiment 1;

[0029] Figure 8 This is an exploded view of the present invention in Example 1.

[0030] In the diagram, there are: camera 1, flexible eyeball 2, eyeball support 3, ball joint 4, ball joint support 5, screw 6, flexible rectus muscle 7, rectus muscle rope 8, common tendon ring platform 9, eyeball shell 10, platform groove 11, camera hole 12, internal boss 13, reserved hole 14, hollow polygon 15, through hole 16, platform hole 17, arc-shaped connecting piece 18, and ball joint hole 19. Detailed Implementation

[0031] The present invention will be further described in detail below through specific embodiments, but this does not limit the scope of the present invention.

[0032] Example 1

[0033] A bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles, its structure is as follows: Figure 1-8 As shown, it includes a two-degree-of-freedom flexible drive parallel mechanism, on which a bionic eye structure is provided. The bionic eye structure includes an eyeball flexible body 2. The two-degree-of-freedom flexible drive parallel mechanism includes a rectus muscle flexible body 7 and a rectus muscle rope 8 symmetrically arranged and connected to the eyeball flexible body 2. The end of the rectus muscle flexible body 7 is provided with a total tendon ring platform 9 that cooperates with the rectus muscle rope 8.

[0034] An eyeball shell 10 is housed within the flexible eyeball body 2. The eyeball shell 10 has an internal protrusion 13 that mates with a camera hole 12 on the flexible eyeball body 2. A camera 1 connected to the internal protrusion 13 is located on the side of the flexible eyeball body 2 away from the flexible rectus muscle body 7. An eyeball support 3, which is gap-fitted to the inner wall of the eyeball shell 10, is located inside the eyeball shell 10. One end of the flexible rectus muscle body 7 is glued to the outer surface of the flexible eyeball body 2, and the other end is glued to the common tendon ring platform 9. The common tendon ring platform 9 has a platform groove 11 that mates with the flexible rectus muscle body 7. The rectus muscle ligament 8 is disposed within the flexible rectus muscle body 7.

[0035] The rectus muscle tether 8 includes two adjustable tethers with a gap fit. One end of each adjustable tether is connected to an arc-shaped connecting piece 18 located on the inner side of the flexible eyeball 2. The adjustable tethers engage with the flexible rectus muscle 7 through pre-drilled holes 14 located on the flexible eyeball 2; the flexible rectus muscle 7 has through holes 16 that are respectively gap-fitted with the adjustable tethers.

[0036] The common tendon ring platform 9 is provided with platform holes 17 that mate with the gap of the adjustment rope, and the platform holes 17 are set in the platform groove 11. The holes 16 are symmetrically arranged longitudinally along the rectus muscle flexible body 7 at the middle position of the rectus muscle flexible body 7; the reserved holes 14 are set at the connection between the eyeball flexible body 2 and the rectus muscle flexible body 7.

[0037] Four rectus muscle flexible bodies 7 are symmetrically arranged on the flexible eyeball 2, and the included angle between adjacent rectus muscle flexible bodies 7 is 90°; the inner side of the rectus muscle flexible body 7 is distributed with gap-fitting hollow polygons 15; the camera of the camera 1 is oriented in the same direction as the line of sight of the bionic eye.

[0038] The bionic eye structure also includes a ball joint bracket 5 mounted on the eyeball support 3; a ball joint 4 is provided on one side of the ball joint bracket 5 to be connected to the ball joint of the eyeball support 3, and a screw 6 is provided on the other side to correspond one-to-one with the rectus muscle flexible body 7. The end of the screw 6 away from the ball joint bracket 5 is connected to the common tendon ring platform 9.

[0039] Based on the rotation requirements of the bionic eye, the four sets of rectus muscle ropes 8 on the side of the common tendon ring platform 9 away from the rectus muscle flexible body 7 are adjusted respectively. By adjusting the extension and contraction of the adjustment ropes in the rectus muscle ropes 8, the adjustment ropes drive the extension and contraction of each rectus muscle flexible body 7 through the platform holes 17 in the platform groove 11. The rectus muscle flexible body 7 deforms and extends along the hollow polygon 15. The adjustment ropes move within the gap-fitting through holes 16 to prevent the deformation of the rectus muscle flexible body 7 from affecting the extension and contraction adjustment of the rectus muscle ropes 8. The adjustment ropes pass through the reserved holes 14. The arc-shaped connecting piece 18 drives the flexible eyeball 2 to move in the set direction. The eyeball shell 10 rotates with the flexible eyeball 2 through the ball joint hole 19 on the eyeball support 3 along the ball joint 4 on the ball joint support 5. The camera 1, which is connected to the internal boss 13 through the camera hole 12 on the flexible eyeball 2, moves with the eyeball shell 10. The screw 6 can keep the ball joint support 5 from moving with the eyeball shell 10, thereby achieving the purpose of two-degree-of-freedom flexible adjustment of the bionic eye. By precisely controlling the rectus muscle rope 8, the bionic eye can be driven to make precise adjustments.

[0040] Example 2

[0041] A bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles differs from Embodiment 1 in that: the adjusting rope is fitted with a plurality of adjusting balls that cooperate with the through hole 16, and the adjusting balls are fitted with adjusting rings that cooperate with the through hole 16.

[0042] Example 3

[0043] A bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism differs from Embodiment 1 in that: a micro spring is provided inside the hollow polygon 15, and the two ends of the micro spring are connected to the inner wall surface of the hollow polygon 15.

[0044] The above description is only a preferred embodiment of the present invention, but is not limited to the above examples. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A bionic eye based on a two-degree-of-freedom parallel mechanism driven by artificial muscles, characterized in that, The invention includes a two-degree-of-freedom flexible drive parallel mechanism, on which a bionic eye structure is provided, the bionic eye structure including a flexible eyeball; the two-degree-of-freedom flexible drive parallel mechanism includes a symmetrically arranged flexible rectus muscle body and a rectus muscle rope connected to the flexible eyeball body, and the end of the flexible rectus muscle body is provided with a common tendon ring platform that cooperates with the rectus muscle rope. One end of the rectus muscle flexible body is glued to the outer surface of the eyeball flexible body, and the other end is glued to the common tendon ring platform. The common tendon ring platform is provided with a platform groove that cooperates with the rectus muscle flexible body; the rectus muscle rope is set in the rectus muscle flexible body. The rectus muscle thong includes two adjustable thongs with interlocking gaps, one end of which is connected to an arc-shaped connecting piece disposed on the inner side of the flexible inner surface of the eyeball; The adjustment cord engages with the rectus muscle flexible body through a pre-drilled hole on the flexible body of the eyeball; the flexible body of the rectus muscle is provided with through holes that respectively engage with the gaps of the adjustment cord; The eyeball flexible body has four rectus muscle flexible bodies symmetrically arranged on it, and the included angle between adjacent rectus muscle flexible bodies is 90°; the inner side of the rectus muscle flexible body has a gap-fitting hollow polygonal shape, and a micro spring is provided in the hollow polygonal shape.

2. The bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism according to claim 1, characterized in that, The flexible eyeball is fitted with an eyeball shell, and the eyeball shell has an internal boss that mates with a camera hole on the flexible eyeball. A camera connected to the internal boss is located on the side of the flexible eyeball away from the rectus muscle. An eyeball support is provided inside the eyeball shell that fits with the inner wall of the eyeball shell.

3. The bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism according to claim 1, characterized in that, The total tendon ring platform is provided with platform holes that mate with the gap of the adjusting rope, and the platform holes are set in the platform groove.

4. The bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism according to claim 3, characterized in that, The through-holes are symmetrically arranged along the longitudinal direction of the rectus muscle flexible body at the middle position of the rectus muscle flexible body; the reserved holes are located at the connection between the eyeball flexible body and the rectus muscle flexible body.

5. The bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism according to claim 2, characterized in that, The camera lens of the camera is oriented in the same direction as the line of sight of the bionic eye.

6. The bionic eye based on an artificial muscle-driven two-degree-of-freedom parallel mechanism according to claim 2 or 3, characterized in that, The bionic eye structure also includes a ball joint bracket mounted on the eyeball support; one side of the ball joint bracket is provided with a ball joint that is connected to the ball joint of the eyeball support, and the other side is provided with a screw that corresponds one-to-one with the rectus muscle flexible body, and the end of the screw away from the ball joint bracket is connected to the common tendon ring platform.

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