Redundant drive multi-degree-of-freedom soft seedling taking manipulator

Abstract

The redundant drive multi-degree-of-freedom soft seedling taking manipulator provided by the invention is provided with two-degree-of-freedom bent flexible fingers, clamping action and radial lifting and placing action can be realized, the flexibility of seedling clamping is improved by the design, the seedling taking and throwing movement track of the seedling taking manipulator is simplified, and the seedling taking and throwing movement track of the seedling taking manipulator is simplified. The design difficulty of a seedling taking mechanical arm or a seedling taking manipulator moving platform is effectively reduced, the posture of seedlings in the seedling transplanting process can be adjusted through the radial up-and-down swing action, seedling falling and stem bending deformation in the seedling transplanting process are reduced, redundant drive modes (including rope drive and air pressure drive pipelines) can be used independently or cooperatively, and the seedling transplanting efficiency is improved. The soft seedling taking manipulator has higher universality due to the redundant driving mode and is suitable for various semi-automatic or automatic transplanters, and compared with a traditional soft manipulator, two driving methods are used, so that the manipulator has higher tail end output force and higher posture keeping capacity and response speed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of manipulator, in particular to a redundant drive multi-degree-of-freedom soft seedling taking manipulator. BACKGROUND

[0002] China is a big country in vegetable planting and consumption, and the vegetable planting area is increasing year by year. At present, the seedling and transplanting technology is adopted in many areas of China, and the mechanized transplanting equipment can effectively improve the planting efficiency, guarantee the quality and yield of vegetables, and reduce the labor intensity of vegetable farmers. At present, the semi-automatic transplanting machine is mainly used in China, and the seedling taking and throwing action still needs manual operation.

[0003] The full-automatic transplanting machine has low popularization rate due to the reasons of price and universality. With the aggravation of population aging and the continuous improvement of urbanization rate, the shortage of agricultural practitioners is urgent, and the popularization and application of full-automatic transplanting machine are needed to reduce the labor input and further improve the efficiency. The key device of full-automatic transplanting machine is the seedling taking and throwing device, and the mainstream scheme is to use end seedling taking needle or seedling taking manipulator to replace the manual seedling taking and throwing action in semi-automatic transplanting machine. The two seedling taking methods have advantages and disadvantages, and the stem clamping method is fast and convenient, and it is not easy to damage the roots, so some scholars have developed various seedling taking manipulators. At present, the seedling taking manipulator mainly uses rigid fingers driven by motors or air cylinders, and some fingers are equipped with flexible buffer layers on the inner side, but the effect is limited. In the design of full-automatic transplanting machine, the seedling taking and throwing trajectory includes clamping process, seedling moving process, seedling throwing process and return process, which makes the seedling taking and throwing manipulator design complex and the manipulator mechanism large.

[0004] In the past two years, some scholars have proposed related theoretical achievements based on soft robot (soft manipulator), and use soft driver structure to replace rigid fingers in order to improve the contact damage of seedling stems. However, soft manipulator also has some disadvantages, such as poor posture holding ability and anti-shaking performance, small clamping force and other problems, which restrict the further improvement of application field and performance; For example: the flexible gripper mentioned in the invention patent application No. 202411587700.5 adopts a multi-air chamber network structure similar to the present patent, but the grid shape and number are different, which can be applied to the application of soft manipulator in agricultural machinery, but it can only realize single degree of freedom bending action, the clamping force is small, the anti-vibration ability is poor, and the finger spacing is not adjustable, which cannot be applied to the transplanting machine without pneumatic system; The flexible seedling taking hand mentioned in the invention patent application No. 202410719543.2 uses flexible film and vacuum adsorption combination, and the seedling taking hand is suitable for large leaf vegetables, so the suitable varieties are few. The invention patent application with application number 202410324247.2 mentions a seedling end actuator for preventing damage to seedlings. It uses a soft gripper with a fin effect. However, the fin effect mainly relies on the passive bending deformation caused by the force on the inside of the fingers to grip the object in a wrapping manner. It is more suitable for gripping round, large-diameter objects, such as apples and tomatoes. However, the diameter of the seedling stem is too small, and the soft fingers cannot be effectively passively bent and deformed. Therefore, the gripping force is small and the seedling is easy to fall. The invention patent with application number 202011486123.2 proposes a parallel soft actuator that uses two sets of pneumatic networks. The two sets of pneumatic networks in this invention patent still achieve forward and reverse bending with the same degree of bending freedom, resulting in low bending flexibility. Summary of the Invention

[0005] (a) Technical problems to be solved To address the aforementioned problems in the prior art, this invention provides a redundantly driven, multi-degree-of-freedom soft seedling-picking robot.

[0006] (II) Technical Solution To achieve the above objectives, the main technical solutions adopted by the present invention include: A redundantly driven, multi-degree-of-freedom soft seedling-picking manipulator, comprising soft fingers, a palm platform, an interdigital adjustment mechanism, a rope traction mechanism, and a pneumatic drive pipeline; The soft fingers are provided in two sets, symmetrically arranged on the palm platform. Each soft finger includes a finger fixing base, a soft finger body, a sealing layer, an anti-slip surface layer, a fixing plate, a traction rope, and a positioning plate. The soft finger body is fixedly installed in the finger fixing seat. The soft finger body has two sets of pneumatic networks arranged symmetrically in the upper and lower positions. The two sets of pneumatic networks are respectively connected to the corresponding pneumatic drive pipelines. Two positioning plates are provided on the surface of the soft finger body away from the finger fixing seat. The two positioning plates are respectively arranged corresponding to the pneumatic networks. The two positioning plates are respectively connected to the corresponding rope traction mechanism through the traction rope. The sealing layer and the anti-slip surface layer are sequentially disposed on the inner surface of the soft finger body; The fixing plate is installed on the finger fixing seat by bolts, thereby fixing the soft finger body in the finger fixing seat; The finger adjustment mechanism is connected to the soft finger and is used to adjust the initial angle of the soft finger.

[0007] Preferably, the pneumatic network includes multiple independent air chambers and air passages connecting each independent air chamber.

[0008] Preferably, the rope traction mechanism includes a motor, an eccentric wheel, a linear bearing, and a transmission link. The motor is mounted on the palm platform and connected to the eccentric wheel. One end of the transmission link is rotatably connected to the eccentric wheel, and the other end of the transmission link is connected to the traction rope. The transmission link is mounted on the palm platform via the linear bearing.

[0009] Preferably, it further includes a finger adjustment mechanism, which includes a polygonal prism limiting rod, a magnetic limiting ring, and a magnetic fixing cover. The polygonal prism limiting rod is fixedly disposed on the top of the finger fixing seat and extends upward through the palm platform. The magnetic limiting ring is fixedly disposed on the top of the palm platform and surrounds the polygonal prism limiting rod. The inner wall of the magnetic limiting ring is provided with limiting tooth grooves. The magnetic fixing cover is fixed to the magnetic limiting ring by magnetic attraction. The bottom of the magnetic fixing cover is provided with limiting teeth corresponding to the limiting tooth grooves, and the magnetic fixing cover has a positioning groove corresponding to the polygonal prism limiting rod.

[0010] Preferably, the soft finger body has a guide hole corresponding to the traction rope. A rubber hose is embedded in the guide rope hole, and the traction rope passes through the rubber hose to connect to the positioning plate.

[0011] Preferably, the soft finger body is made of a first flexible material with a Shore A hardness of 30 to 50, and the sealing layer and anti-slip surface layer are made of a second flexible material with a Shore A hardness of 60 to 80.

[0012] Preferably, both the first flexible material and the second flexible material are made of silicone.

[0013] (III) Beneficial Effects The beneficial effects of this invention are as follows: 1. The flexible finger with two degrees of freedom designed in this invention can not only perform the gripping action, but also the radial lifting and placing action. This design improves the flexibility of gripping seedlings, simplifies the seedling picking and placing motion trajectory of the seedling picking robot arm, effectively reduces the design difficulty of the seedling picking robot arm or seedling picking robot hand moving platform, and the radial up and down swinging action can adjust the posture of the seedlings during the transplanting process, reducing seedling falling and stem bending deformation during transplanting. 2. The redundant drive methods (including rope drive and pneumatic drive pipeline) can be used independently or in combination. The redundant drive methods make the soft seedling picking robot more versatile and suitable for a variety of semi-automatic or automatic transplanters. Compared with traditional soft robots, the present invention uses two drive methods to make the robot have higher end-effector output force, higher posture maintenance ability and response speed. Attached Figure Description

[0014] Figure 1 A schematic diagram of a redundantly driven, multi-degree-of-freedom soft seedling-retrieving manipulator; Figure 2 A top view schematic diagram of a redundantly driven, multi-degree-of-freedom soft seedling-retrieving manipulator. Figure 3 A schematic diagram of the exploded structure of a soft finger; Figure 4 A schematic diagram of the horizontal bending structure of a soft finger; Figure 5 A schematic diagram of the radial upward bending structure of a soft finger; Figure 6 This is a schematic diagram of the interphalangeal adjustment mechanism; Figure 7 This is a schematic diagram of the magnetic fixing cover. Figure 8 This is a schematic diagram of the rope traction mechanism. Figure 9 This is a schematic diagram illustrating the usage of a redundantly driven, multi-degree-of-freedom soft seedling-picking robot.

[0015] [Explanation of Labels in the Attached Image] 1. Palm-sized platform; 2. Finger adjustment mechanism; 21. Polygonal prism limiting rod; 22. Magnetic limiting ring; 23. Magnetic fixing cover; 24. Limiting teeth; 25. Positioning groove; 3. Soft fingers; 31. Finger fixing seat; 32. Soft finger body; 33. Pneumatic network; 34. Traction rope; 35. Positioning plate; 36. Sealing layer; 37. Anti-slip surface layer; 38. Fixing plate; 4. Rope traction mechanism; 41. Motor; 42. Eccentric wheel; 43. Linear bearing; 44. Transmission connecting rod. Detailed Implementation

[0016] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] Please refer to Figures 1 to 9 The present invention provides a redundantly driven multi-degree-of-freedom soft seedling picking manipulator, comprising soft fingers 3, finger adjustment mechanism 2, palm platform 1, rope traction mechanism 4, and pneumatic drive pipeline. Two sets of soft fingers 3 are provided, which are symmetrically arranged on the palm platform 1. The soft fingers 3 include a finger fixing seat 31, a soft finger body 32, a sealing layer 36, an anti-slip surface layer 37, a fixing plate 38, a traction rope 34, and a positioning plate 35. The soft finger body 32 is fixedly installed in the finger fixing seat 31. Two sets of pneumatic networks 33 are arranged symmetrically on the surface of the soft finger body 32. The two sets of pneumatic networks 33 are respectively connected to the corresponding pneumatic drive pipelines. Two positioning plates 35 are provided on the surface of the soft finger body 32 away from the finger fixing seat 31. The two positioning plates 35 are respectively arranged corresponding to the pneumatic networks 33. The two positioning plates 35 are respectively connected to the corresponding rope traction mechanism 4 through the traction rope 34. A sealing layer 36 and an anti-slip surface layer 37 are sequentially disposed on the inner surface of the soft finger body 32; The fixing plate 38 is installed on the finger fixing seat 31 by bolts, and the soft finger body 32 is fixed in the finger fixing seat 31; The finger adjustment mechanism 2 is connected to the soft finger 3 and is used to adjust the initial angle of the soft finger 3; In use, both sets of rope traction mechanisms 4 pull the traction rope 34 simultaneously. Under the action of traction force, the soft finger body 32 bends in the horizontal direction. When only one set of rope traction mechanisms 4 pulls the traction rope 34, and the traction rope 34 connected to the other set of rope traction mechanisms 4 is in a slack state, the soft finger body 32 will bend in the radial direction. The pneumatic drive pipeline simultaneously inputs the same air pressure into the two sets of pneumatic networks 33. After the pneumatic network 33 in the soft finger body 32 is supplied with air pressure, the soft finger body 32 expands as a whole, and its length increases, while the sealing layer 36 and the anti-slip surface layer 37 do not expand. At this time, the soft finger body 32 bends in the horizontal direction. When the two sets of pneumatic networks 33... When the internal air pressure is different, the expansion amplitude of the upper and lower halves of the soft finger body 32 is different, which allows the soft finger body 32 to bend radially. In this application, the rope traction mechanism 4 or the air pressure drive pipeline can enable the soft finger 3 to achieve the bending action of gripping and the bending action of vertical bending. The two degrees of freedom improve the flexibility of the seedling picking robot, simplify the design complexity of the robot arm, and can also effectively reduce the size of the transplanter. The actions of the two degrees of freedom can be achieved by changing the air pressure or by rope drive, so it is a redundant drive. The redundant drive achieves higher versatility, improves the gripping force and posture maintenance ability of the soft robot, and improves the existing defects of soft robots.

[0018] In this embodiment, the pneumatic network 33 includes multiple independent air chambers and air channels connecting each independent air chamber. In use, the pneumatic drive pipeline inputs gas into the pneumatic network 33, which then enters each independent air chamber, causing each independent air chamber to expand. This results in the overall length of the soft finger body 32 being extended, while the sealing layer 36 and the anti-slip surface layer 37 do not expand. This results in a smaller deformation of the sealing layer 36 and the anti-slip surface layer 37. It is only under the constraint of the sealing layer 36 and the anti-slip surface layer 37 that the expanded soft finger body 32 can bend.

[0019] It should be noted that the pneumatic drive line is used to inject compressed gas into the pneumatic network 33 and can control the amount of compressed gas input.

[0020] refer to Figure 8 In this embodiment, the rope traction mechanism 4 includes a motor 41, an eccentric wheel 42, a linear bearing 43, and a transmission link 44. The motor 41 is mounted on the palm platform 1 and connected to the eccentric wheel 42. One end of the transmission link 44 is rotatably connected to the eccentric wheel 42, and the other end of the transmission link 44 is connected to the traction rope 34. The transmission link 44 is mounted on the palm platform 1 through the linear bearing 43. In use, the motor 41 drives the eccentric wheel 42 to rotate, and with the cooperation of the online bearing and the transmission link 44, the traction control of the traction rope 34 is realized.

[0021] refer to Figure 6 and Figure 7 In this embodiment, a finger adjustment mechanism 2 is also included. The finger adjustment mechanism 2 includes a polygonal prism limiting rod 21, a magnetic limiting ring 22, and a magnetic fixing cover 23. The polygonal prism limiting rod 21 is fixedly installed on the top of the finger fixing seat 31 and extends upward through the palm platform 1. The magnetic limiting ring 22 is fixedly installed on the top of the palm platform 1 and surrounds the polygonal prism limiting rod 21. The inner wall of the magnetic limiting ring 22 is provided with limiting tooth grooves. The magnetic fixing cover 23 is fixed on the magnetic limiting ring 22 by magnetic attraction. The bottom of the magnetic fixing cover 23 is provided with limiting teeth 24 corresponding to the limiting tooth grooves, and the magnetic fixing cover 23 is provided with positioning grooves 25 corresponding to the polygonal prism limiting rod 21. When in use, open the magnetic fixing cover 23, and then adjust the angle between the soft fingers 3 according to actual needs before installing the magnetic fixing cover 23 to fix the adjusted soft fingers 3. It can adapt to different seedling trays and has high versatility and convenience.

[0022] In this embodiment, the soft finger body 32 has a guide hole corresponding to the traction rope 34. A rubber hose is embedded in the guide hole. The traction rope 34 passes through the rubber hose and connects to the positioning plate 35. The embedded rubber hose prevents the traction rope 34 from leaking compressed air during the pulling process.

[0023] In this embodiment, the soft finger body 32 is made of a first flexible material with a Shore A hardness of 30 to 50, and the sealing layer 36 and the anti-slip surface layer 37 are made of a second flexible material with a Shore A hardness of 60 to 80. Due to the hardness difference between the soft finger body 32 and the sealing layer 36 and the anti-slip surface layer 37, the deformation of the sealing layer 36 and the anti-slip surface layer 37 is lower, making it easier to bend when the soft finger body 32 expands and elongates.

[0024] In this embodiment, both the first flexible material and the second flexible material are made of silicone.

[0025] The working principle of this invention is as follows: Two sets of rope traction mechanisms 4 pull the traction rope 34 simultaneously. Under the action of traction force, the soft finger body 32 bends in the horizontal direction. When only one set of rope traction mechanisms 4 pulls the traction rope 34, and the traction rope 34 connected to the other set of rope traction mechanisms 4 is in a slack state, the soft finger body 32 will bend in the radial direction. The pneumatic drive pipeline simultaneously inputs the same air pressure into the two sets of pneumatic networks 33. After the pneumatic network 33 in the soft finger body 32 is supplied with air pressure, the soft finger body 32 expands as a whole, and its length increases, while the sealing layer 36 and the anti-slip surface layer 37 do not expand. At this time, the soft finger body 32 bends in the horizontal direction. When the air pressure input into the two sets of pneumatic networks 33 is different, the expansion amplitude of the upper half and the lower half of the soft finger body 32 is different, which allows the soft finger body 32 to bend in the radial direction.

[0026] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention's specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

[0027] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A redundantly driven, multi-degree-of-freedom soft seedling-picking robot, characterized in that, Soft fingers, palm platform, finger adjustment mechanism, rope traction mechanism, and pneumatic drive pipeline; The soft fingers are provided in two sets, symmetrically arranged on the palm platform. Each soft finger includes a finger fixing base, a soft finger body, a sealing layer, an anti-slip surface layer, a fixing plate, a traction rope, and a positioning plate. The soft finger body is fixedly installed in the finger fixing seat. The soft finger body has two sets of pneumatic networks arranged symmetrically in the upper and lower positions. The two sets of pneumatic networks are respectively connected to the corresponding pneumatic drive pipelines. Two positioning plates are provided on the surface of the soft finger body away from the finger fixing seat. The two positioning plates are respectively arranged corresponding to the pneumatic networks. The two positioning plates are respectively connected to the corresponding rope traction mechanism through the traction rope. The sealing layer and the anti-slip surface layer are sequentially disposed on the inner surface of the soft finger body; The fixing plate is installed on the finger fixing seat by bolts, thereby fixing the soft finger body in the finger fixing seat; The finger adjustment mechanism is connected to the soft finger and is used to adjust the initial angle of the soft finger.

2. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 1, characterized in that, The pneumatic network includes multiple independent air chambers and air channels connecting each independent air chamber.

3. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 1, characterized in that, The rope traction mechanism includes a motor, an eccentric wheel, a linear bearing, and a transmission link. The motor is mounted on the palm platform and connected to the eccentric wheel. One end of the transmission link is rotatably connected to the eccentric wheel, and the other end of the transmission link is connected to the traction rope. The transmission link is mounted on the palm platform via the linear bearing.

4. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 1, characterized in that, It also includes a finger adjustment mechanism, which comprises a polygonal prism limiting rod, a magnetic limiting ring, and a magnetic fixing cover. The polygonal prism limiting rod is fixedly disposed on the top of the finger fixing seat and extends upward through the palm platform. The magnetic limiting ring is fixedly disposed on the top of the palm platform and surrounds the polygonal prism limiting rod. The inner wall of the magnetic limiting ring is provided with limiting tooth grooves. The magnetic fixing cover is fixed to the magnetic limiting ring by magnetic attraction. The bottom of the magnetic fixing cover is provided with limiting teeth corresponding to the limiting tooth grooves, and the magnetic fixing cover has a positioning groove corresponding to the polygonal prism limiting rod.

5. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 1, characterized in that, The soft finger body has guide holes corresponding to the traction rope. A rubber hose is embedded in the guide rope hole, and the traction rope passes through the rubber hose to connect to the positioning plate.

6. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 1, characterized in that, The soft finger body is made of a first flexible material with a Shore A hardness of 30 to 50, and the sealing layer and anti-slip surface layer are made of a second flexible material with a Shore A hardness of 60 to 80.

7. The redundantly driven multi-degree-of-freedom soft seedling-picking robot according to claim 6, characterized in that, Both the first flexible material and the second flexible material are made of silicone.

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